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Sample records for human serum colorimetric

  1. Improved colorimetric determination of serum zinc.

    Science.gov (United States)

    Johnson, D J; Djuh, Y Y; Bruton, J; Williams, H L

    1977-07-01

    We show how zinc may easily be quantified in serum by first using an optimum concentration of guanidine hydrochloride to cause release of zinc from proteins, followed by complexation of released metals with cyanide. The cyanide complex of zinc is preferentially demasked with chloral hydrate, followed by a colorimetric reaction between zinc and 4-(2-pyridylazo)resorcinol. This is a sensitive water-soluble ligand; its complex with zinc has an absorption maximum at 497 nm. Values found by this technique compare favorably with those obtained by atomic absorption spectroscopy.

  2. Standardization of Neisseria meningitidis Serogroup B Colorimetric Serum Bactericida Assay

    Science.gov (United States)

    Rodríguez, Tamara; Lastre, Miriam; Cedré, Barbara; Campo, Judith del; Bracho, Gustavo; Zayas, Caridad; Taboada, Carlos; Díaz, Miriam; Sierra, Gustavo; Pérez, Oliver

    2002-01-01

    The correlate of protection for serogroup B meningococci is not currently known, but for serogroup C it is believed to be the serum bactericidal assay (SBA). The current SBAs are labor intensive and the variations in protocols among different laboratories make interpretation of results difficult. A colorimetric SBA (cSBA), based on the ability of Neisseria meningitidis serogroup B to consume glucose, leading to acid production, was standardized by using group B strain Cu385-83 as the target. The cSBA results were compared to those obtained for a traditional colony-counting microassay (mSBA). Glucose and bromocresol purple pH indicator were added to the medium in order to estimate growth of cSBA target cell survivors through color change. Different variants of the assay parameters were optimized: growth of target cells (Mueller Hinton agar plates), target cell number (100 CFU/per well), and human complement source used at a final concentration of 25%. After the optimization, three other group B strains (H44/76, 490/91, and 511/91) were used as targets for the cSBA. The selection of the assay parameters and the standardization of cSBA were done with 13 sera from vaccinated volunteers. The titers were determined as the higher serum dilution that totally inhibited the bacterial growth marked by the color invariability of the pH indicator. This was detected visually as well as spectrophotometrically and was closely related to a significant difference in the growth of target cell survivors determined using Student’s t test. Intralaboratory reproducibility was ±1 dilution. The correlation between bactericidal median titers and specific immunoglobulin G serum concentration by enzyme immunoassay was high (r = 0.910, P < 0.01). The bactericidal titers generated by the cSBA and the mSBA were nearly identical, and there was a high correlation between the two assays (r = 0.974, P < 0.01). The standardized cSBA allows easy, fast, and efficient evaluation of samples. PMID

  3. Highly sensitive colorimetric detection of glucose in a serum based on DNA-embeded Au@Ag core–shell nanoparticles

    International Nuclear Information System (INIS)

    Kang, Fei; Xu, Kun; Hou, Xiangshu

    2015-01-01

    Glucose is a key energy substance in diverse biology and closely related to the life activities of the organism. To develop a simple and sensitive method for glucose detection is extremely urgent but still remains a key challenge. Herein, we report a colorimetric glucose sensor in a homogeneous system based on DNA-embedded core–shell Au@Ag nanoparticles. In this assay, a glucose substrate was first catalytically oxidized by glucose oxidase to produce H 2 O 2 which would further oxidize and gradually etch the outer silver shell of Au@Ag nanoparticles. Afterwards, the solution color changed from yellow to red and the surface plasmon resonance (SPR) band of Au@Ag nanoparticles declined and red-shifted from 430 to 516 nm. Compared with previous silver-based glucose colorimetric detection strategies, the distinctive SPR band change is superior to the color variation, which is critical to the high sensitivity of this assay. Benefiting from the outstanding optical property, robust stability and well-dispersion of the core–shell Au@AgNPs hybrid, this colorimetric assay obtained a detection limit of glucose as low as 10 nM, which is at least a 10-fold improvement over other AgNPs-based procedures. Moreover, this optical biosensor was successfully employed to the determination of glucose in fetal bovine serum. (paper)

  4. Optimization of a colorimetric assay for glycosylated human serum albumin

    International Nuclear Information System (INIS)

    Bohney, J.P.; Feldhoff, R.C.

    1986-01-01

    The thiobarbituric acid (TBA) assay has been used for several years to quantitate the amount of glucose which has been non-enzymatically linked to hemoglobin and other proteins. The ketoamine-protein adduct is converted to 5-hydroxymethylfurfural (HMF) by mild hydrolysis with oxalic acid. Reaction of HMF with TBA yields a colored product which has an absorbance maximum at 443 nm. Several modifications of the original procedure has been published, but none permit the unambiguous quantitation of glycosylated human serum albumin (glc-HSA). Problems relate to reagent preparation and stability, the time and temperature of hydrolysis, the choice of standards, and background color corrections. The authors have found that maximum color yield occurs after hydrolysis in an autoclave for 2 h. This increases the sensitivity 3-fold and cuts the assay time in half relative to hydrolysis for 4.5 h at 100 0 C. A NaBH 4 reduction of a parallel protein sample must be performed to correct for variable background color associated with different sample sources and amounts. HMF can be used as a standard, however, corrections must be made for HMF degradation. Fructose is a better standard, but HMF formation from fructose is faster than formation from glc-HSA. This may result in an underestimate of percent glycosylation. The best standard appears to be glc-HSA prepared with [ 3 H]glucose. It appears that with proper controls and standards the TBA assay can be used to determine actual rather than relative percent glycosylation

  5. Optimization of a colorimetric assay for glycosylated human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Bohney, J.P.; Feldhoff, R.C.

    1986-05-01

    The thiobarbituric acid (TBA) assay has been used for several years to quantitate the amount of glucose which has been non-enzymatically linked to hemoglobin and other proteins. The ketoamine-protein adduct is converted to 5-hydroxymethylfurfural (HMF) by mild hydrolysis with oxalic acid. Reaction of HMF with TBA yields a colored product which has an absorbance maximum at 443 nm. Several modifications of the original procedure has been published, but none permit the unambiguous quantitation of glycosylated human serum albumin (glc-HSA). Problems relate to reagent preparation and stability, the time and temperature of hydrolysis, the choice of standards, and background color corrections. The authors have found that maximum color yield occurs after hydrolysis in an autoclave for 2 h. This increases the sensitivity 3-fold and cuts the assay time in half relative to hydrolysis for 4.5 h at 100/sup 0/C. A NaBH/sub 4/ reduction of a parallel protein sample must be performed to correct for variable background color associated with different sample sources and amounts. HMF can be used as a standard, however, corrections must be made for HMF degradation. Fructose is a better standard, but HMF formation from fructose is faster than formation from glc-HSA. This may result in an underestimate of percent glycosylation. The best standard appears to be glc-HSA prepared with (/sup 3/H)glucose. It appears that with proper controls and standards the TBA assay can be used to determine actual rather than relative percent glycosylation.

  6. Evaluation of tetrazolium-based semiautomatic colorimetric assay for measurement of human antitumor cytotoxicity

    International Nuclear Information System (INIS)

    Heo, D.S.; Park, J.G.; Hata, K.; Day, R.; Herberman, R.B.; Whiteside, T.L.

    1990-01-01

    A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-based colorimetric assay was developed and compared with 51Cr release from different adherent tumor cell targets (human squamous cell carcinoma lines of the head and neck established in our laboratory, melanoma, and colorectal carcinoma) using 5-7-day human lymphokine-activated killer cells and monocyte-depleted peripheral blood lymphocytes as effectors. With adherent tumor cell targets, MTT colorimetry was more sensitive than the 51Cr release assay in measuring the antitumor activity of effectors: median, 4385 (range, 988-8144) versus median, 1061 (range, 582-7294) lytic units (the number of effector cells required to lyse 20% of 5 x 10(3) targets)/10(7) effectors (P less than 0.01). Background effects (without effector cells) were comparable in 4-h assays (9% versus 10%) between MTT colorimetry and 51Cr release. In 24-h assays, MTT colorimetry showed higher antitumor activity (70-100% versus 40-60% lysis at 1:1 effector:target cell ratio) but lower background effects (6% versus 38%) than 51Cr release assay. Thus, MTT colorimetry was more sensitive, did not use radiolabeled targets, required fewer effector cells, and was easier, less expensive, and better adaptable to serial monitoring of effector cell function in cancer patients. This colorimetric assay is especially well suited to adherent tumor cell targets. The use of adherent tumor cell monolayers, as opposed to trypsinized single cell suspensions, provides an opportunity to measure interactions of effector cells with enzymatically unaltered solid tumor targets. Because of the greater sensitivity of the colorimetric assay, the transformation of MTT data into lytic units, as commonly used for 51Cr release assays, required an adjustment to avoid the extrapolation based on the exponential fit equation

  7. False positive acetaminophen concentrations in icteric serum

    Directory of Open Access Journals (Sweden)

    L. de Jong

    2016-04-01

    Full Text Available Introduction: Serum concentrations of acetaminophen are measured to predict the risk of hepatotoxicity in cases of acetaminophen overdose and to identify acetaminophen use in patients with acute liver injury without a known cause. The acetaminophen concentration determines if treatment with N-acetyl cysteine, the antidote for acetaminophen poisoning, is warranted. Description: A 49-year-old woman was admitted to our hospital with a hepatic encephalopathy and a total serum bilirubin concentration of 442 µmol/l. The acetaminophen concentration of 11.5 mg/l was measured with an enzymatic-colorimetric assay, thus treatment with N-acetyl cysteine was started. Interestingly, the acetaminophen concentration remained unchanged (11.5–12.3 mg/l during a period of 4 consecutive days. In contrast, the acetaminophen concentration measured by HPLC, a chromatographic technique, remained undetectable Discussion: In the presented case, elevated bilirubin was the most likely candidate to interfere with acetaminophen assay causing false positive results. Bilirubin has intense absorbance in the ultraviolet and visible regions of the electromagnetic spectrum and for that reason it causes interference in an enzymatic-colorimetric assay. Conclusion: False positive acetaminophen laboratory test results may be found in icteric serum, when enzymatic-colorimetric assays are used for determination of an acetaminophen concentration. Questionable acetaminophen results in icteric serum should be confirmed by a non-enzymatic method, by means of ultrafiltration of the serum, or by dilution studies. Keywords: Acetaminophen, Enzymatic-colorimetric assays, HPLC, Bilirubin, Interference, Paracetamol, Liver failure, Jaundice

  8. Comparison of serum copper determination by colorimetric and atomic absorption spectrometric methods in seven different laboratories. The S.F.B.C. (Société Française de Biologie Clinique) Trace Element Group.

    Science.gov (United States)

    Arnaud, J; Chappuis, P; Zawislak, R; Houot, O; Jaudon, M C; Bienvenu, F; Bureau, F

    1993-02-01

    An interlaboratory collaborative trial was conducted on the determination of serum copper using two different methods, based on colorimetry (test combination Copper, Boehringer Mannheim, Mannheim, Germany) and flame atomic absorption spectrometry (FAAS). The general performance of the colorimetric method was below that of FAAS, except for sensitivity and linear range, as assessed by detection limit (0.44 versus 1.32 mumol/L) and upper limit of linearity (150 versus 50 mumol/L). The range of the between-run CVs and the recovery of standard additions were, respectively, 2.3-11.9% and 92-127% for the colorimetric method and 1.1-6.0% and 93-101% for the FAAS method. Interferences were minimal with both methods. The two techniques correlated satisfactorily (the correlation coefficients ranged from 0.945-0.970 among laboratories) but the colorimetric assay exhibited slightly higher results than the FAAS method. Each method was transferable among laboratories.

  9. DNA-Catalytically Active Gold Nanoparticle Conjugates-Based Colorimetric Multidimensional Sensor Array for Protein Discrimination.

    Science.gov (United States)

    Wei, Xiangcong; Chen, Zhengbo; Tan, Lulu; Lou, Tianhong; Zhao, Yan

    2017-01-03

    A series of single-strand oligonucleotides functionalized catalytically active gold nanoparticle (AuNPs) as nonspecific receptors have been designed to build a protein sensing array. We take advantage of the correlation between the catalytic activity and the exposed surface area of AuNPs, i.e., DNA-proteins interactions mask the surface area of AuNPs, leading to poor catalytic performance of AuNPs. As the number of DNA-bound proteins increases, the surfaces of AuNPs become more masked; thus, the time of 4- nitrophenol/NaBH 4 reaction for color change (yellow → colorless) of the solution increases. Taking advantage of three nonspecific SH-labeled DNA sequences (A15, C15, and T15) as array sensing elements and the color-change time (CCT) of the solution as signal readout, colorimetric response patterns can be obtained on the array and identified via linear discriminant analysis (LDA). Eleven proteins have been completely distinguished with 100% accuracy with the naked eye at the 30 nM level. Remarkably, two similar proteins (bovine serum albumin and human serum albumin), two different proteins (bovine serum albumin and concanavalin) at the same concentration, and the mixtures of the two proteins with different molar ratios have been discriminated with 100%. The practicability of this sensor array is further validated by high accuracy (100%) identification of 11 proteins in human serum samples.

  10. Discovering the enzyme mimetic activity of metal-organic framework (MOF) for label-free and colorimetric sensing of biomolecules.

    Science.gov (United States)

    Wang, Ying; Zhu, Yingjing; Binyam, Atsebeha; Liu, Misha; Wu, Yinan; Li, Fengting

    2016-12-15

    A label-free sensing strategy based on the enzyme-mimicking activity of MOF was demonstrated for colorimetric detection of biomolecules. Firstly obvious blue color was observed due to the high efficiency of peroxidase-like catalytic activity of Fe-MIL-88A (an ion-based MOF material) toward 3,3',5,5'-tetramethylbenzidine (TMB). Then in the presence of target biomolecule and corresponding aptamer, the mimetic activity of Fe-MIL-88A can be strongly inhibited and used directly to realize the colorimetric detection. On the basis of the interesting findings, we designed a straightforward, label-free and sensitive colorimetric method for biomolecule detection by using the enzyme mimetic property of MOF coupling with molecular recognition element. Compared with the existed publications, our work breaks the routine way by setting up an inorganic-organic MOF-aptamer hybrid platform for colorimetric determination of biomolecules, expanding the targets scope from H2O2 or glucose to biomolecules. As a proof of concept, thrombin and thrombin aptamer was used as a model analyte. The limit of detection of 10nM can be achieved with naked eyes and ultrahigh selectivity of thrombin toward numerous interfering substances with 10-fold concentration was demonstrated significantly. Of note, the method was further applied for the detection of thrombin in human serum samples, showing the results in agreement with those values obtained in an immobilization buffer by the colorimetric method. This inorganic-organic MOF-aptamer sensing strategy may in principle be universally applicable for the detection of a range of environmental or biomedical molecules of interests. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Quantitative determination of albumin in microlitre amounts of rat serum: With a short note on serum albumin levels in ageing rats

    NARCIS (Netherlands)

    Leeuw-Israel, F.R. de; Arp-Neefjes, J.M.; Hollander, C.F.

    1967-01-01

    A simple dye binding method for determining rat serum albumin, which employs the anionic dye 2-(4′-hydroxybenzneeazo) benzoic acid (HBABA) is described. Albumin in 5μ1 of serum is determined colorimetrically. Purified rat albumin is used as a primary standard and rat serum as a reference sample.

  12. The Human Serum Metabolome

    Science.gov (United States)

    Psychogios, Nikolaos; Hau, David D.; Peng, Jun; Guo, An Chi; Mandal, Rupasri; Bouatra, Souhaila; Sinelnikov, Igor; Krishnamurthy, Ramanarayan; Eisner, Roman; Gautam, Bijaya; Young, Nelson; Xia, Jianguo; Knox, Craig; Dong, Edison; Huang, Paul; Hollander, Zsuzsanna; Pedersen, Theresa L.; Smith, Steven R.; Bamforth, Fiona; Greiner, Russ; McManus, Bruce; Newman, John W.; Goodfriend, Theodore; Wishart, David S.

    2011-01-01

    Continuing improvements in analytical technology along with an increased interest in performing comprehensive, quantitative metabolic profiling, is leading to increased interest pressures within the metabolomics community to develop centralized metabolite reference resources for certain clinically important biofluids, such as cerebrospinal fluid, urine and blood. As part of an ongoing effort to systematically characterize the human metabolome through the Human Metabolome Project, we have undertaken the task of characterizing the human serum metabolome. In doing so, we have combined targeted and non-targeted NMR, GC-MS and LC-MS methods with computer-aided literature mining to identify and quantify a comprehensive, if not absolutely complete, set of metabolites commonly detected and quantified (with today's technology) in the human serum metabolome. Our use of multiple metabolomics platforms and technologies allowed us to substantially enhance the level of metabolome coverage while critically assessing the relative strengths and weaknesses of these platforms or technologies. Tables containing the complete set of 4229 confirmed and highly probable human serum compounds, their concentrations, related literature references and links to their known disease associations are freely available at http://www.serummetabolome.ca. PMID:21359215

  13. Human erythrocytes inhibit complement-mediated solubilization of immune complexes by human serum

    International Nuclear Information System (INIS)

    Dorval, B.L.

    1987-01-01

    The aim of this study was to develop an autologus human system to evaluate the effects of human erythrocytes on solubilization of immune complex precipitates (IC) by human serum. Incubation of IC with fresh human serum or guinea pig serum resulted in solubilization of IC. When packed erythrocytes were added to human serum or guinea pig serum binding of IC to the erythrocyte occurred and IC solubilization was inhibited significantly (p <.025). Sheep erythrocytes did not bind IC or inhibit IC solubilization. To evaluate the role of human erythrocyte complement receptor (CR1) on these findings, human erythrocytes were treated with trypsin or anti-CR1 antibodies. Both treatments abrogated IC binding to human erythrocytes but did not affect the ability of the human erythrocyte to inhibit IC solubilization. Radioimmunoassay was used to measure C3, C4 and C5 activation in human serum after incubation with IC, human erythrocytes, human erythrocytes plus IC, whole blood or in whole blood plus IC

  14. Elemental analysis of human serum and serum protein fractions by thermal neutron activation

    International Nuclear Information System (INIS)

    Woittiez, J.R.W.

    1984-01-01

    Some applications of thermal neutron activation for the determination of elemental contents in human serum and human serum protein fractions are presented. Firstly total serum is dealt with, secondly serum protein fractions obtained by gel filtration are described. A brief review on the role of (trace) elements in human health and disease and a compilation of literature data for elemental contents in human serum, as obtained by neutron activation techniques, are given. The most important sources of statistical and systematic errors are evaluated. Results for the contents of sodium, potassium, magnesium, bromine, iron, copper, zinc, selenium, rubidium, cesium and antimony in serum are given, with emphasis on control of accuracy and precision. The possible relation between selenium in blood and cancer occurrence in humans is discussed. The results of elemental analyses from cancer patients and from a patient receiving a cytostatic treatment are presented. A survey of literature results for the determination of protein-bound elemental contents in serum is presented. Subsequently, results from a study on the behaviour of elements during gel filtration are discussed. Gel-element and protein-element interactions are studied. Finally the protein-bound occurrence of trace elements in human serum is determined by gel filtration and neutron activation analysis. Results for both desalting and fractionation are given, for the elements bromine, copper, manganese, vanadium, selenium, zinc, rubidium, iron and iodine. (Auth.)

  15. A novel, colorimetric neutralization assay for measuring antibodies to influenza viruses.

    Science.gov (United States)

    Lehtoranta, Liisa; Villberg, Anja; Santanen, Riitta; Ziegler, Thedi

    2009-08-01

    A colorimetric cell proliferation assay for measuring neutralizing antibodies to influenza viruses in human sera is described. Following a 90-min incubation, the serum-virus mixture was transferred to Madin-Darby canine kidney cells cultured in 96-well plates. After further incubation for three days, a tetrazolium salt was added to the wells. Cellular mitochondrial dehydrogenases cleave the tetrazolium salt to formazan, and the resulting color change is read by a spectrophotometer. The absorbance values correlate directly to the number of viable cells in the assay well and thus also to the neutralizing activity of influenza-specific antibodies present in the serum. With the few hands-on manipulations required, this assay allows simultaneous testing of a considerable number of sera, offers opportunities for automation, and is suitable for use under biosafety level-3 conditions. The test was used to study the antibody response after the administration of seasonal, inactivated, trivalent influenza vaccine. Antibody titers determined by the neutralization test in pre- and post-vaccination serum pairs were compared with those obtained by the hemagglutination inhibition assay. The neutralization test yielded higher pre- and post-vaccination titers and a larger number of significant increases in post-vaccination antibody titer than the hemagglutination inhibition test. This new test format could serve as a valuable laboratory tool for influenza vaccine studies.

  16. Novel colorimetric sensor for oral malodour

    Energy Technology Data Exchange (ETDEWEB)

    Alagirisamy, Nethaji; Hardas, Sarita S. [Hindustan Unilever Research Center, 64 Main Road, Whitefield, Bangalore 560066 (India); Jayaraman, Sujatha, E-mail: sujatha.jayaraman@unilever.com [Hindustan Unilever Research Center, 64 Main Road, Whitefield, Bangalore 560066 (India)

    2010-02-19

    Volatile sulphur compounds are the primary constituents of oral malodour. Quantitative tools for the detection of oral malodour are beneficial to evaluate the intensity of malodour, analyse its causes and monitor the effectiveness of customized treatments. We have developed an objective, cost effective, do-it-yourself colorimetric sensor for oral malodour quantification. The sensor consisted of a sensing solution, a gas sampling unit for collecting a known volume of mouth air and a photometric detector. The sensing solution was iodine and the depletion of iodine on reaction with hydrogen sulphide was detected colorimetrically using starch. The detection limit of the sensor is 0.05 {mu}g L{sup -1} of hydrogen sulphide, which is fit-for-purpose for oral malodour detection in healthy subjects as well as halitosis patients. Volatile sulphur compounds in mouth air were quantified in healthy human volunteers using this portable sensor and the detected levels were in the range of 0.2-0.4 {mu}g L{sup -1}. There was a good correlation between the VSC levels detected by the colorimetric sensor and halimeter (R{sup 2} = 0.934). The developed sensor can be easily fabricated in the laboratory, and it shows high potential to be used as a clinical evaluation tool for oral malodour assessments.

  17. Novel colorimetric sensor for oral malodour

    International Nuclear Information System (INIS)

    Alagirisamy, Nethaji; Hardas, Sarita S.; Jayaraman, Sujatha

    2010-01-01

    Volatile sulphur compounds are the primary constituents of oral malodour. Quantitative tools for the detection of oral malodour are beneficial to evaluate the intensity of malodour, analyse its causes and monitor the effectiveness of customized treatments. We have developed an objective, cost effective, do-it-yourself colorimetric sensor for oral malodour quantification. The sensor consisted of a sensing solution, a gas sampling unit for collecting a known volume of mouth air and a photometric detector. The sensing solution was iodine and the depletion of iodine on reaction with hydrogen sulphide was detected colorimetrically using starch. The detection limit of the sensor is 0.05 μg L -1 of hydrogen sulphide, which is fit-for-purpose for oral malodour detection in healthy subjects as well as halitosis patients. Volatile sulphur compounds in mouth air were quantified in healthy human volunteers using this portable sensor and the detected levels were in the range of 0.2-0.4 μg L -1 . There was a good correlation between the VSC levels detected by the colorimetric sensor and halimeter (R 2 = 0.934). The developed sensor can be easily fabricated in the laboratory, and it shows high potential to be used as a clinical evaluation tool for oral malodour assessments.

  18. Colorimetric determination of sildenafil citrate (Viagra) through ion-associate complex formation.

    Science.gov (United States)

    Amin, Alaa S; Moustafa, Moustafa E; El-Dosoky, Reham

    2009-01-01

    A simple, quick, accurate, and sensitive colorimetric method is described for the determination of sildenafil citrate (SLD). The method is based on the reaction of SLD with Congo Red, Sudan II, and Gentian Violet in buffered aqueous solutions at pH 2.5, 6.5, and 11.0, respectively, to give highly colored soluble ion-associate complex species; the colored products are quantitated colorimetrically at 523, 554, and 569 nm, respectively. The various experimental conditions were optimized. The stoichiometric ratio was found to be 1:1 for all ion associates; the calculated logarithmic stability constants were 8.51, 7.79, and 5.58, respectively. Beer's law was obeyed over the concentration range of 0.2-7.0 microg/mL, whereas the Ringbom optimum concentration range was 0.4-6.5 microg/mL. Values for molar absorptivity, Sandell sensitivity, and detection and quantification limits were also calculated. The proposed method was successfully applied to the determination of SLD in Viagra tablets and in serum samples by using the technique of standard additions with mean accuracy values of 100.06 +/- 1.14, 99.87 +/- 0.70, and 99.86 +/- 0.97% for Viagra tablets and 99.88 +/- 0.60, 99.90 +/- 0.90, and 100.24 +/- 0.80% for serum samples, respectively.

  19. Colorimetric detection of Cr (VI) based on the leaching of gold nanoparticles using a paper-based sensor.

    Science.gov (United States)

    Guo, Jian-Feng; Huo, Dan-Qun; Yang, Mei; Hou, Chang-Jun; Li, Jun-Jie; Fa, Huan-Bao; Luo, Hui-Bo; Yang, Ping

    2016-12-01

    Herein, we have developed a simple, sensitive and paper-based colorimetric sensor for the selective detection of Chromium (Ⅵ) ions (Cr (VI)). Silanization-titanium dioxide modified filter paper (STCP) was used to trap bovine serum albumin capped gold nanoparticles (BSA-Au NPs), leading to the fabrication of BSA-Au NPs decorated membrane (BSA-Au NPs/STCP). The BSA-Au NPs/STCP operated on the principle that BSA-Au NPs anchored on the STCP were gradually etched by Cr (VI) as the leaching process of gold in the presence of hydrobromic acid (HBr) and hence induced a visible color change. Under optimum conditions, the paper-based colorimetric sensor showed clear color change after reaction with Cr (VI) as well as with favorable selectivity to a variety of possible interfering counterparts. The amount-dependent colorimetric response was linearly correlated with the Cr (VI) concentrations ranging from 0.5µM to 50.0µM with a detection limit down to 280nM. Moreover, the developed cost-effective colorimetric sensor has been successfully applied to real environmental samples which demonstrated the potential for field applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Multiplexed Colorimetric Solid-Phase Extraction

    Science.gov (United States)

    Gazda, Daniel B.; Fritz, James S.; Porter, Marc D.

    2009-01-01

    Multiplexed colorimetric solid-phase extraction (MC-SPE) is an extension of colorimetric solid-phase extraction (C-SPE) an analytical platform that combines colorimetric reagents, solid phase extraction, and diffuse reflectance spectroscopy to quantify trace analytes in water. In CSPE, analytes are extracted and complexed on the surface of an extraction membrane impregnated with a colorimetric reagent. The analytes are then quantified directly on the membrane surface using a handheld diffuse reflectance spectrophotometer. Importantly, the use of solid-phase extraction membranes as the matrix for impregnation of the colorimetric reagents creates a concentration factor that enables the detection of low concentrations of analytes in small sample volumes. In extending C-SPE to a multiplexed format, a filter holder that incorporates discrete analysis channels and a jig that facilitates the concurrent operation of multiple sample syringes have been designed, enabling the simultaneous determination of multiple analytes. Separate, single analyte membranes, placed in a readout cartridge create unique, analyte-specific addresses at the exit of each channel. Following sample exposure, the diffuse reflectance spectrum of each address is collected serially and the Kubelka-Munk function is used to quantify each water quality parameter via calibration curves. In a demonstration, MC-SPE was used to measure the pH of a sample and quantitate Ag(I) and Ni(II).

  1. Localized surface plasmon resonance of gold nanoparticles as colorimetric probes for determination of Isoniazid in pharmacological formulation

    Science.gov (United States)

    Zargar, Behrooz; Hatamie, Amir

    2013-04-01

    Isoniazid is an important antibiotic, which is widely used to treat tuberculosis. This study presents a colorimetric method for the determination of Isoniazid based on localized surface plasmon resonance (LSPR) property of gold nanoparticles. An LSPR band is produced by reducing gold ions in solution using Isoniazid as the reducing agent. Influences of the following relevant variables were examined and optimized in the experiment, formation time of gold nanoparticles, pH, buffer and stabilizer. These tests demonstrated that under optimum conditions the absorbance of Au nanoparticles at 530 nm related linearly to the concentration of Isoniazid in the range of 1.0-8.0 μg mL-1 with a detection limit of 0.98 μg mL-1. This colorimetric method has been successfully applied to the determine Isoniazid in tablets and spiked serum samples. The proposed colorimetric assay exhibits good reproducibility and accuracy, providing a simple and rapid method for analysis of Isoniazid.

  2. Universal, colorimetric microRNA detection strategy based on target-catalyzed toehold-mediated strand displacement reaction

    Science.gov (United States)

    Park, Yeonkyung; Lee, Chang Yeol; Kang, Shinyoung; Kim, Hansol; Park, Ki Soo; Park, Hyun Gyu

    2018-02-01

    In this work, we developed a novel, label-free, and enzyme-free strategy for the colorimetric detection of microRNA (miRNA), which relies on a target-catalyzed toehold-mediated strand displacement (TMSD) reaction. The system employs a detection probe that specifically binds to the target miRNA and sequentially releases a catalyst strand (CS) intended to trigger the subsequent TMSD reaction. Thus, the presence of target miRNA releases the CS that mediates the formation of an active G-quadruplex DNAzyme which is initially caged and inactivated by a blocker strand. In addition, a fuel strand that is supplemented for the recycling of the CS promotes another TMSD reaction, consequently generating a large number of active G-quadruplex DNAzymes. As a result, a distinct colorimetric signal is produced by the ABTS oxidation promoted by the peroxidase mimicking activity of the released G-quadruplex DNAzymes. Based on this novel strategy, we successfully detected miR-141, a promising biomarker for human prostate cancer, with high selectivity. The diagnostic capability of this system was also demonstrated by reliably determining target miR-141 in human serum, showing its great potential towards real clinical applications. Importantly, the proposed approach is composed of separate target recognition and signal transduction modules. Thus, it could be extended to analyze different target miRNAs by simply redesigning the detection probe while keeping the same signal transduction module as a universal signal amplification unit, which was successfully demonstrated by analyzing another target miRNA, let-7d.

  3. Bacteriostatic enterochelin-specific immunoglobulin from normal human serum

    Energy Technology Data Exchange (ETDEWEB)

    Moore, D.G.; Yancey, R.J.; Lankford, C.E.; Earhart, C.F.

    1980-02-01

    Heat-inactivated normal human serum produces iron-reversible bacteriostasis of a number of microorganisms. This inhibitory effect was abolished by adsorption of serum with ultraviolet-killed cells of species that produce the siderophore enterochelin. Bacteriostasis also was alleviated by asorption of serum with 2,3-dihydroxy-N-benzoyl-L-serine, a degradation product of enterochelin, bound to the insoluble matrix AH-Sepharose 4B. Our results indicate that enterochelin-specific immunoglobulins exist in normal human serum. These immunoglobulins may act synergistically with transferrin to effect bacteriostasis of enterochelin-producing pathogens.

  4. Plasmon-Based Colorimetric Nanosensors for Ultrasensitive Molecular Diagnostics.

    Science.gov (United States)

    Tang, Longhua; Li, Jinghong

    2017-07-28

    Colorimetric detection of target analytes with high specificity and sensitivity is of fundamental importance to clinical and personalized point-of-care diagnostics. Because of their extraordinary optical properties, plasmonic nanomaterials have been introduced into colorimetric sensing systems, which provide significantly improved sensitivity in various biosensing applications. Here we review the recent progress on these plasmonic nanoparticles-based colorimetric nanosensors for ultrasensitive molecular diagnostics. According to their different colorimetric signal generation mechanisms, these plasmonic nanosensors are classified into two categories: (1) interparticle distance-dependent colorimetric assay based on target-induced forming cross-linking assembly/aggregate of plasmonic nanoparticles; and (2) size/morphology-dependent colorimetric assay by target-controlled growth/etching of the plasmonic nanoparticles. The sensing fundamentals and cutting-edge applications will be provided for each of them, particularly focusing on signal generation and/or amplification mechanisms that realize ultrasensitive molecular detection. Finally, we also discuss the challenge and give our future perspective in this emerging field.

  5. Colorimetric detection of glucose based on ficin with peroxidase-like activity

    Science.gov (United States)

    Pang, Yanjiao; Huang, Zili; Yang, Yufang; Long, Yijuan; Zheng, Huzhi

    2018-01-01

    In this work, we developed a colorimetric biosensing system for glucose detection by coupling the peroxidase-like of ficin and the glucose oxidase (GOx). GOx can catalyze the oxidation of glucose to produce H2O2, then, ficin catalyzes the oxidation of peroxidase substrate 3,3‧,5,5‧-tetramethylbenzidine (TMB) by H2O2 to produce a blue color reaction. The present sensing system showed a linear response toward glucose detection over range of 2.0-100 μM with a detection limit of 0.5 μM. This system is simple, low cost, highly sensitive and selective for glucose detection, and was also applied to measuring glucose in human serum. Furthermore, in order to expand the application of ficin in biological sensing, we immobilized ficin onto the SiO2@Fe3O4 NPs, which exhibited the merits of recycling as well as allowing the repeated detection of glucose. Thus it may provide great potential applications in biomedicine, biotechnology and environmental chemistry.

  6. Achromatic-chromatic colorimetric sensors for on-off type detection of analytes.

    Science.gov (United States)

    Heo, Jun Hyuk; Cho, Hui Hun; Lee, Jin Woong; Lee, Jung Heon

    2014-12-21

    We report the development of achromatic colorimetric sensors; sensors changing their colors from achromatic black to other chromatic colors. An achromatic colorimetric sensor was prepared by mixing a general colorimetric indicator, whose color changes between chromatic colors, and a complementary colored dye with no reaction to the targeted analyte. As the color of an achromatic colorimetric sensor changes from black to a chromatic color, the color change could be much easily recognized than general colorimetric sensors with naked eyes. More importantly, the achromatic colorimetric sensors enable on-off type recognition of the presence of analytes, which have not been achieved from most colorimetric sensors. In addition, the color changes from some achromatic colorimetric sensors (achromatic Eriochrome Black T and achromatic Benedict's solution) could be recognized with naked eyes at much lower concentration ranges than normal chromatic colorimetric sensors. These results provide new opportunities in the use of colorimetric sensors for diverse applications, such as harsh industrial, environmental, and biological detection.

  7. Significance of Serum Leptin Assessment in Chronic Renal Patients on Dialysis

    International Nuclear Information System (INIS)

    Salem, E.S; Tawfik, M.S; ELaseily, E.S.

    2013-01-01

    The number of patients suffering from renal failure indicating dialysis has been increasing worldwide. Leptin hormone plays an important role in the development of malnutrition in these patients. Bone produces different hormones, such as osteocalcin (OC), which influences energy expenditure in humans. Disturbances in mineral metabolism and bone disease are common complications of chronic kidney disease (CKD). There are increasing evidences suggesting that these disorders in mineral and bone metabolism are associated with increased risk of cardiovascular calcification, morbidity, and mortality, especially among those who undergo maintenance renal dialysis. The present study was carried out to evaluate the importance of serum leptin assessment in renal dialysis patients. Serum leptin level was estimated by radioimmunoassay (RIA) using recombinant human leptin (Leptin- Human Ria-CT). Immunoradiometric assay kit (host IRMA) was used for in-vitro quantitative measurement of human intact OC. Serum creatinine level was determined by colorimetric method. This study included 60 patients (twenty suffering from CKD, thirty on dialysis and ten healthy controls). Serum leptin, OC and creatinine were found to be higher in patients of both groups compared to that of controls. Maximum increase was observed in patients on dialysis. From these results it is possible to conclude that, although patients with chronic renal disease exhibited significant increase in serum leptin, yet sudden additional increase can be related to serious pathology that can end in renal failure. The present study also highlighted the importance of OC as a marker of disturbed mineral-bone metabolism in chronic kidney disease (CKD) patients and those receiving dialysis that could lead to the atherosclerosis, extravascular calcification, morbidity and mortality. KeywoRdSLeptin, osteocalcin, Radioimmunoassay (RIA), Chronic kidney disease, Renal dialysis, Creatinine.

  8. A Novel Colorimetric Immunoassay Utilizing the Peroxidase Mimicking Activity of Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Hyun Gyu Park

    2013-05-01

    Full Text Available A simple colorimetric immunoassay system, based on the peroxidase mimicking activity of Fe3O4 magnetic nanoparticles (MNPs, has been developed to detect clinically important antigenic molecules. MNPs with ca. 10 nm in diameter were synthesized and conjugated with specific antibodies against target molecules, such as rotaviruses and breast cancer cells. Conjugation of the MNPs with antibodies (MNP-Abs enabled specific recognition of the corresponding target antigenic molecules through the generation of color signals arising from the colorimetric reaction between the selected peroxidase substrate, 3,3',5,5'-tetramethylbenzidine (TMB and H2O2. Based on the MNP-promoted colorimetric reaction, the target molecules were detected and quantified by measuring absorbance intensities corresponding to the oxidized form of TMB. Owing to the higher stabilities and economic feasibilities of MNPs as compared to horseradish peroxidase (HRP, the new colorimetric system employing MNP-Abs has the potential of serving as a potent immunoassay that should substitute for conventional HRP-based immunoassays. The strategy employed to develop the new methodology has the potential of being extended to the construction of simple diagnostic systems for a variety of biomolecules related to human cancers and infectious diseases, particularly in the realm of point-of-care applications.

  9. Biodegradable nanoporous nanoparticles for human serum analysis

    International Nuclear Information System (INIS)

    Pujia, A.; De Angelis, F.; Scumaci, D.; Gaspari, M.; Liberale, C.; Candeloro, P.; Cuda, G.; Di Fabrizio, E.

    2010-01-01

    Modern medicine and biology search for new powerful tool for biomarkers discovery, appears one of the most promising approaches for early cancer diagnosis. Nowadays, the low molecular weight fraction of human serum is the most informative source of biomarkers, but their study and identification are very difficult due to the incredible complexity of the raw human serum. In this work we describe a novel tool for the filtration of crude human serum or other bio-fluid based on water soluble nanoparticles. Nanoparticles with a pore size of about 2-3 nm, and diameters of 200 nm were obtained by ultrasonication of nanoporous silicon. The porous nanoparticles act as a nanosieve able to exclusively harvest the low molecular weight fraction of the fluid thanks to a controllable pore size. After a short incubation, the infiltrated nanosieves can be extracted from the starting fluid by means of centrifugation, and dissolved in water in a few minutes to give the captured molecules back in their native state, without degradation and contamination. The raw fluid is so split in two components of high and low molecular weight, that are both available for further analyses with any other investigation technique. Here, fluorescence spectroscopy, 2D-gel electrophoresis, and mass spectrometry are exploited to show the split of different bio-fluids under physiological condition. A cut-off (or split level) of 13 kDa is demonstrated also for human serum.

  10. Radioimmunoassay for determination of thyroglobulin in human serum

    International Nuclear Information System (INIS)

    Rodriguez Cabrera, M.E.; Blanca Fernandez, S.; Baldor Navarro, F.; Rodriguez Gonzalez, J.C.

    1996-01-01

    We described the development and analytical evaluation of a radioimmunoassay with double antibody in liquid phase for human serum thyroglobulin determination using a set of reagents produced in the National Institute of Endocrinology. The reference interval for normal population was 5.7 - 44 ng/ml (X± 2DS; n=170). The intra-assay precipision was 8.1 % (control serum A) and 7.0 (control serum B) and the inter-assay precision was 9.1 % (control serum A) and 9.2 % (control serum B). The sensibility was 4.7 ng/ml and the recovery was 95 %

  11. Serum-converted platelet lysate can substitute for fetal bovine serum in human mesenchymal stromal cell cultures.

    Science.gov (United States)

    Mojica-Henshaw, Mariluz P; Jacobson, Pam; Morris, Julie; Kelley, Linda; Pierce, Jan; Boyer, Michael; Reems, Jo-Anna

    2013-12-01

    Fetal bovine serum (FBS) is commonly used as a serum supplement for culturing human mesenchymal stromal cells (hMSCs). However, human cells grown in FBS, especially for extended periods, risk potential exposure to bovine immunogenic proteins and infectious agents. To address this issue, we investigated the ability of a novel human platelet serum supplement to substitute for FBS in hMSC cultures. Platelet lysate-serum (PL-serum) was converted from platelet lysate-plasma (PL-plasma) that was manufactured from pooled platelet-rich plasma (PRP) apheresis units. Growth factor levels and the number of residual intact platelets in PL-serum and PL-plasma were compared with enzyme-linked immunosorbent assays and flow cytometry, respectively. Proliferation responses of hMSCs cultured in PL-serum, PL-plasma, or FBS were assessed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the immunophenotype of harvested hMSCs was evaluated by flow cytometry and tri-lineage differentiation potential was evaluated by assessing adipogenic, osteogenic and chondrogenic development. Selected growth factor levels in PL-serum were not significantly different from PL-plasma (P > 0.05). hMSC cultures supplemented with PL-serum had comparable growth kinetics to PL-plasma, and hMSC yields were consistently greater than with FBS. hMSCs harvested from cultures supplemented with PL-serum, PL-plasma or FBS had similar cell surface phenotypes and maintained tri-lineage differentiation potential. PL-serum, similar to PL-plasma, can substitute for FBS in hMSC cultures. Use of PL-serum, in contrast to PL-plasma, has an added advantage of not requiring addition of a xenogeneic source of heparin, providing a completely xeno-free culture medium. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  12. Complete human serum maintains viability and chondrogenic potential of human synovial stem cells: suitable conditions for transplantation.

    Science.gov (United States)

    Mizuno, Mitsuru; Katano, Hisako; Otabe, Koji; Komori, Keiichiro; Kohno, Yuji; Fujii, Shizuka; Ozeki, Nobutake; Horie, Masafumi; Tsuji, Kunikazu; Koga, Hideyuki; Muneta, Takeshi; Sekiya, Ichiro

    2017-06-13

    In our clinical practice, we perform transplantations of autologous synovial mesenchymal stem cells (MSCs) for cartilage and meniscus regenerative medicine. One of the most important issues to ensuring clinical efficacy involves the transport of synovial MSCs from the processing facility to the clinic. Complete human serum (100% human serum) is an attractive candidate material in which to suspend synovial MSCs for their preservation during transport. The purpose of this study was to investigate whether complete human serum maintained MSC viability and chondrogenic potential and to examine the optimal temperature conditions for the preservation of human synovial MSCs. Human synovium was harvested from the knees of 14 donors with osteoarthritis during total knee arthroplasty. Passage 2 synovial MSCs were suspended at 2 million cells/100 μL in Ringer's solution or complete human serum at 4, 13, and 37 °C for 48 h. These cells were analyzed for live cell rates, cell surface marker expression, metabolic activity, proliferation, and adipogenic, calcification, and chondrogenic differentiation potentials before and after preservation. After preservation, synovial MSCs maintained higher live cell rates in human serum than in Ringer's solution at 4 and 13 °C. Synovial MSCs preserved in human serum at 4 and 13 °C also maintained high ratios of propidium iodide - and annexin V - cells. MSC surface marker expression was not altered in cells preserved at 4 and 13 °C. The metabolic activities of cells preserved in human serum at 4 and 13 °C was maintained, while significantly reduced in other conditions. Replated MSCs retained their proliferation ability when preserved in human serum at 4 and 13 °C. Adipogenesis and calcification potential could be observed in cells preserved in each condition, whereas chondrogenic potential was retained only in cells preserved in human serum at 4 and 13 °C. The viability and chondrogenic potential of synovial MSCs were

  13. Real-time monitoring of enzyme-free strand displacement cascades by colorimetric assays

    Science.gov (United States)

    Duan, Ruixue; Wang, Boya; Hong, Fan; Zhang, Tianchi; Jia, Yongmei; Huang, Jiayu; Hakeem, Abdul; Liu, Nannan; Lou, Xiaoding; Xia, Fan

    2015-03-01

    The enzyme-free toehold-mediated strand displacement reaction has shown potential for building programmable DNA circuits, biosensors, molecular machines and chemical reaction networks. Here we report a simple colorimetric method using gold nanoparticles as signal generators for the real-time detection of the product of the strand displacement cascade. During the process the assembled gold nanoparticles can be separated, resulting in a color change of the solution. This assay can also be applied in complex mixtures, fetal bovine serum, and to detect single-base mismatches. These results suggest that this method could be of general utility to monitor more complex enzyme-free strand displacement reaction-based programmable systems or for further low-cost diagnostic applications.The enzyme-free toehold-mediated strand displacement reaction has shown potential for building programmable DNA circuits, biosensors, molecular machines and chemical reaction networks. Here we report a simple colorimetric method using gold nanoparticles as signal generators for the real-time detection of the product of the strand displacement cascade. During the process the assembled gold nanoparticles can be separated, resulting in a color change of the solution. This assay can also be applied in complex mixtures, fetal bovine serum, and to detect single-base mismatches. These results suggest that this method could be of general utility to monitor more complex enzyme-free strand displacement reaction-based programmable systems or for further low-cost diagnostic applications. Electronic supplementary information (ESI) available: Experimental procedures and analytical data are provided. See DOI: 10.1039/c5nr00697j

  14. Analysis of trace elements in serum from human eating irradiated food

    International Nuclear Information System (INIS)

    Huang Zongzhi; Zhou Hongdi; Chen Shijie; Gao Sumei

    1987-01-01

    A method of trace element analysis by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AEC) in serum from human eating food preserved by irradiation is described. Trace element analysis in human serum is one of the research projects concerning the wholesomeness. 78 serum samples of the human eating food preserved by irradiation were collected. After ashing and solving ICP-AES analysis of serum is performed for detecting 12 trace elements in specimen solution. The detection limitations are in the range of 10 -2 - 10 -3 ppm for differemt elements. The recoveries of elements are over 73%. Concentrations of 12 trace elements in 78 human serum has been calculated with F and t tests at PDP 11/70 computer and it was concluded that there is no significant difference between testing group and control group

  15. Colorimetric detection for paper-based biosensing applications

    Science.gov (United States)

    Brink, C.; Joubert, T.-H.

    2016-02-01

    Research on affordable point-of-care health diagnostics is rapidly advancing1. Colorimetric biosensor applications are typically qualitative, but recently the focus has been shifted to quantitative measurements2,3. Although numerous qualitative point-of-care (POC) health diagnostic devices are available, the challenge exists of developing a quantitative colorimetric array reader system that complies with the ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, Deliverable to end-users) principles of the World Health Organization4. This paper presents a battery powered 8-bit tonal resolution colorimetric sensor circuit for paper microfluidic assays using low cost photo-detection circuitry and a low-power LED light source. A colorimetric 3×3-pixel array reader was developed for rural environments where resources and personnel are limited. The device sports an ultralow-power E-ink paper display. The colorimetric device includes integrated GPS functionality and EEPROM memory to log measurements with geo-tags for possible analysis of regional trends. The device competes with colour intensity measurement techniques using smartphone cameras, but proves to be a cheaper solution, compensating for the typical performance variations between cameras of different brands of smartphones. Inexpensive methods for quantifying bacterial assays have been shown using desktop scanners, which are not portable, and cameras, which suffer severely from changes in ambient light in different environments. Promising colorimetric detection results have been demonstrated using devices such as video cameras5, digital colour analysers6, flatbed scanners7 or custom portable readers8. The major drawback of most of these methods is the need for specialized instrumentation and for image analysis on a computer.

  16. Analysis of Drug Effects on Primary Human Coronary Artery Endothelial Cells Activated by Serum Amyloid A

    Directory of Open Access Journals (Sweden)

    K. Lakota

    2018-01-01

    Full Text Available Background. RA patients have a higher incidence of cardiovascular diseases compared to the general population. Serum amyloid A (SAA is an acute-phase protein, upregulated in sera of RA patients. Aim. To determine the effects of medications on SAA-stimulated human coronary artery endothelial cells (HCAEC. Methods. HCAEC were preincubated for 2 h with medications from sterile ampules (dexamethasone, methotrexate, certolizumab pegol, and etanercept, dissolved in medium (captopril or DMSO (etoricoxib, rosiglitazone, meloxicam, fluvastatin, and diclofenac. Human recombinant apo-SAA was used to stimulate HCAEC at a final 1000 nM concentration for 24 hours. IL-6, IL-8, sVCAM-1, and PAI-1 were measured by ELISA. The number of viable cells was determined colorimetrically. Results. SAA-stimulated levels of released IL-6, IL-8, and sVCAM-1 from HCAEC were significantly attenuated by methotrexate, fluvastatin, and etoricoxib. Both certolizumab pegol and etanercept significantly decreased PAI-1 by an average of 43%. Rosiglitazone significantly inhibited sVCAM-1 by 58%. Conclusion. We observed marked influence of fluvastatin on lowering cytokine production in SAA-activated HCAEC. Methotrexate showed strong beneficial effects for lowering released Il-6, IL-8, and sVCAM-1. Interesting duality was observed for NSAIDs, with meloxicam exhibiting opposite-trend effects from diclofenac and etoricoxib. This represents unique insight into specific responsiveness of inflammatory-driven HCAEC relevant to atherosclerosis.

  17. Probing cocaine-antibody interactions in buffer and human serum.

    Directory of Open Access Journals (Sweden)

    Muthu Ramakrishnan

    Full Text Available Despite progress in cocaine immunotherapy, the kinetic and thermodynamic properties of antibodies which bind to cocaine and its metabolites are not well understood. It is also not clear how the interactions between them differ in a complex matrix such as the serum present in the human body. In the present study, we have used microscale thermophoresis (MST, isothermal titration calorimetry (ITC, and surface plasmon resonance (SPR we have evaluated the affinity properties of a representative mouse monoclonal (mAb08 as well as those of polyclonal antibodies purified from vaccinated mouse and human patient serum.MST analysis of fluorescently tagged mAb08 binding to cocaine reveals an approximately 15 fold decrease in its equilibrium dissociation constant in 20-50% human serum compared with that in saline buffer. A similar trend was also found using enriched polyclonal antibodies purified from vaccinated mice and patient serum, for which we have used fluorescently tagged bovine serum albumin conjugated to succinyl norcocaine (BSA-SNC. This conjugate closely mimics both cocaine and the hapten used to raise these antibodies. The ITC data also revealed that cocaine has a moderate affinity of about 2 µM to 20% human serum and very little interaction with human serum albumin or nonspecific human IgG at that concentration range. In a SPR inhibition experiment, the binding of mAb08 to immobilized BSA-SNC was inhibited by cocaine and benzoylecgonine in a highly competitive manner, whereas the purified polyclonal antibodies from vaccinated humans and mice, revealed preferential selectivity to pharmacologically active cocaine but not to the inactive metabolite benzoylecgonine. We have also developed a simple binding model to simulate the challenges associated with cocaine immunotherapy using the variable quantitative and kinetic properties of the antibodies.High sensitivity calorimetric determination of antibody binding to cocaine and its metabolites provide

  18. Antitumor evaluation of epigallocatechin gallate by colorimetric methods

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Soon Ok [Korean Ginseng and Tobacco Research institute, Daejon (Korea, Republic of); Kim, Il Kwang; Baek, Seung Hwa; Han, Du Seok [Wonkwang Unvi., Iksan (Korea, Republic of)

    1998-08-01

    In the present study, we were evaluated cytotoxic effects of epigallocatechin gallate in human skin melanoma cells such as HTB-69. The light microscopic study showed morphological changes of the treated cells. Disruptions in cell organelles were determined by colorimetric methods; 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, neutral red (NR) assay and sulforhodamine B protein (SRB) as-say. These results suggest that epigallocatechin gallate retains a potential antitumor activity.

  19. Pancreatic elastase in human serum. Determination by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Geokas, M.C. (Univ. of California, Davis); Brodrick, J.W.; Johnson, J.H.; Largman, C.

    1977-01-10

    This study demonstrates that a serine endopeptidase of pancreatic origin (elastase 2) circulates in human blood. A specific and highly sensitive radioimmunoassay has been developed for pancreatic elastase 2 in human serum. The inactivation of elastase 2 employed as radioiodinated tracer with an active site-specific reagent (phenylmethanesulfonyl fluoride) was necessary to prevent its binding by serum ..cap alpha../sub 1/-antitrypsin and ..cap alpha../sub 2/-macroglobulin while maintaining its immunoreactivity. The assay is based upon competition of standard human pancreatic elastase 2 with /sup 125/I-labeled phenylmethanesulfonyl elastase 2 for specific antibody binding sites, after which a second antibody precipitation step is used to separate bound from free /sup 125/I-labeled phenylmethanesulfonyl elastase 2. The minimum detectable concentration of elastase 2 was 0.9 ng/ml. The average normal fasting serum level determined was 71 ng/ml, approximately 80-fold greater than the minimum detectable amount.

  20. Supplements in human islet culture: human serum albumin is inferior to fetal bovine serum.

    Science.gov (United States)

    Avgoustiniatos, Efstathios S; Scott, William E; Suszynski, Thomas M; Schuurman, Henk-Jan; Nelson, Rebecca A; Rozak, Phillip R; Mueller, Kate R; Balamurugan, A N; Ansite, Jeffrey D; Fraga, Daniel W; Friberg, Andrew S; Wildey, Gina M; Tanaka, Tomohiro; Lyons, Connor A; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

    2012-01-01

    Culture of human islets before clinical transplantation or distribution for research purposes is standard practice. At the time the Edmonton protocol was introduced, clinical islet manufacturing did not include culture, and human serum albumin (HSA), instead of fetal bovine serum (FBS), was used during other steps of the process to avoid the introduction of xenogeneic material. When culture was subsequently introduced, HSA was also used for medium supplementation instead of FBS, which was typically used for research islet culture. The use of HSA as culture supplement was not evaluated before this implementation. We performed a retrospective analysis of 103 high-purity islet preparations (76 research preparations, all with FBS culture supplementation, and 27 clinical preparations, all with HSA supplementation) for oxygen consumption rate per DNA content (OCR/DNA; a measure of viability) and diabetes reversal rate in diabetic nude mice (a measure of potency). After 2-day culture, research preparations exhibited an average OCR/DNA 51% higher (p < 0.001) and an average diabetes reversal rate 54% higher (p < 0.05) than clinical preparations, despite 87% of the research islet preparations having been derived from research-grade pancreata that are considered of lower quality. In a prospective paired study on islets from eight research preparations, OCR/DNA was, on average, 27% higher with FBS supplementation than that with HSA supplementation (p < 0.05). We conclude that the quality of clinical islet preparations can be improved when culture is performed in media supplemented with serum instead of albumin.

  1. Physiological serum copper concentrations found in malignancies cause unfolding induced aggregation of human serum albumin in vitro.

    Science.gov (United States)

    Rizvi, Asim; Furkan, Mohd; Naseem, Imrana

    2017-12-15

    Malignancies are characterized by several drastic metabolic changes, one of which is a progressive rise in the levels of serum copper. This rise in serum copper is documented across all malignancies and across malignancies in several species. This study aims to explore in vitro the effect of increased copper levels on the structure of the blood protein human serum albumin. Exposure of human serum albumin to physiologically relevant copper concentrations for 21 days resulted in structural modifications in the protein which were evident by changes in the intrinsic florescence. A loss of the predominantly alpha helical structure of human serum albumin was recorded along with a tendency to form protein aggregates. This aggregation was characterized by Thioflavin T and Congo Red assays. Rayleigh light scattering and turbidity assays confirmed aggregation. The aggregates were visually confirmed using transmission electron microscopy. This is the first report implicating increased copper levels as a cause of aggregation of blood proteins in malignancies. The physiological and biochemical implications of this phenomenon are discussed. Copyright © 2017. Published by Elsevier Inc.

  2. Human serum activates CIDEB-mediated lipid droplet enlargement in hepatoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Singaravelu, Ragunath [Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1N 6N5 (Canada); National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Lyn, Rodney K. [Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5 (Canada); National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Srinivasan, Prashanth [National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Delcorde, Julie [Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1N 6N5 (Canada); National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Steenbergen, Rineke H.; Tyrrell, D. Lorne [Department of Medical Microbiology and Immunology, University of Alberta (Canada); Li Ka Shing Institute of Virology, Katz Centre for Pharmacy and Health Research, Edmonton, Alberta T6G 2S2 (Canada); Pezacki, John P., E-mail: John.Pezacki@nrc-cnrc.gc.ca [Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5 (Canada); National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada)

    2013-11-15

    Highlights: •Human serum induced differentiation of hepatoma cells increases cellular lipid droplet (LD) size. •The observed increase in LD size correlates with increased PGC-1α and CIDEB expression. •Induction of CIDEB expression correlates with rescue of VLDL secretion and loss of ADRP. •siRNA knockdown of CIDEB impairs the human serum mediated increase in LD size. •This system represents a cost-efficient model to study CIDEB’s role in lipid biology. -- Abstract: Human hepatocytes constitutively express the lipid droplet (LD) associated protein cell death-inducing DFFA-like effector B (CIDEB). CIDEB mediates LD fusion, as well as very-low-density lipoprotein (VLDL) maturation. However, there are limited cell culture models readily available to study CIDEB’s role in these biological processes, as hepatoma cell lines express negligible levels of CIDEB. Recent work has highlighted the ability of human serum to differentiate hepatoma cells. Herein, we demonstrate that culturing Huh7.5 cells in media supplemented with human serum activates CIDEB expression. This activation occurs through the induced expression of PGC-1α, a positive transcriptional regulator of CIDEB. Coherent anti-Stokes Raman scattering (CARS) microscopy revealed a correlation between CIDEB levels and LD size in human serum treated Huh7.5 cells. Human serum treatment also resulted in a rapid decrease in the levels of adipose differentiation-related protein (ADRP). Furthermore, individual overexpression of CIDEB was sufficient to down-regulate ADRP protein levels. siRNA knockdown of CIDEB revealed that the human serum mediated increase in LD size was CIDEB-dependent. Overall, our work highlights CIDEB’s role in LD fusion, and presents a new model system to study the PGC-1α/CIDEB pathway’s role in LD dynamics and the VLDL pathway.

  3. Human serum activates CIDEB-mediated lipid droplet enlargement in hepatoma cells

    International Nuclear Information System (INIS)

    Singaravelu, Ragunath; Lyn, Rodney K.; Srinivasan, Prashanth; Delcorde, Julie; Steenbergen, Rineke H.; Tyrrell, D. Lorne; Pezacki, John P.

    2013-01-01

    Highlights: •Human serum induced differentiation of hepatoma cells increases cellular lipid droplet (LD) size. •The observed increase in LD size correlates with increased PGC-1α and CIDEB expression. •Induction of CIDEB expression correlates with rescue of VLDL secretion and loss of ADRP. •siRNA knockdown of CIDEB impairs the human serum mediated increase in LD size. •This system represents a cost-efficient model to study CIDEB’s role in lipid biology. -- Abstract: Human hepatocytes constitutively express the lipid droplet (LD) associated protein cell death-inducing DFFA-like effector B (CIDEB). CIDEB mediates LD fusion, as well as very-low-density lipoprotein (VLDL) maturation. However, there are limited cell culture models readily available to study CIDEB’s role in these biological processes, as hepatoma cell lines express negligible levels of CIDEB. Recent work has highlighted the ability of human serum to differentiate hepatoma cells. Herein, we demonstrate that culturing Huh7.5 cells in media supplemented with human serum activates CIDEB expression. This activation occurs through the induced expression of PGC-1α, a positive transcriptional regulator of CIDEB. Coherent anti-Stokes Raman scattering (CARS) microscopy revealed a correlation between CIDEB levels and LD size in human serum treated Huh7.5 cells. Human serum treatment also resulted in a rapid decrease in the levels of adipose differentiation-related protein (ADRP). Furthermore, individual overexpression of CIDEB was sufficient to down-regulate ADRP protein levels. siRNA knockdown of CIDEB revealed that the human serum mediated increase in LD size was CIDEB-dependent. Overall, our work highlights CIDEB’s role in LD fusion, and presents a new model system to study the PGC-1α/CIDEB pathway’s role in LD dynamics and the VLDL pathway

  4. EL4 cell-based colorimetric toxin neutralization activity assays for determination of neutralizing anti-ricin antibodies.

    Science.gov (United States)

    Lindsey, Changhong Y; Brown, J Edward; Torabazar, Nahid R; Smith, Leonard A

    2013-01-01

    A recombinant ricin toxin A-chain 1-33/44-198 vaccine (RVEc), developed at the United States Army Medical Research Institute of Infectious Diseases as a vaccine candidate, is under investigation in a phase 1 clinical study. To effectively evaluate the immunogenicity of this ricin vaccine and to eliminate the use of radioactive material, an EL4 cell-based colorimetric toxin neutralization activity (TNA) assay using a CellTiter 96 AQueous One Solution Cell Proliferation Assay Reagent has been developed, optimized, and applied in the vaccine efficacy studies. The TNA assay measures the protective neutralizing anti-ricin antibodies in animal sera by determining the cell viability after ricin exposure in the assay system and comparing it to a purified mouse polyclonal antiricin IgG standard curve. The standard curve of the anti-ricin TNA assay closely fits a four-parameter logistic regression model. The unknown test sample concentration was expressed as microg/mL, but not the 50% effective concentration (EC50), which was determined by most TNA assays. The neutralizing endpoint titers, not the 50% effective dilution (ED50), of human specimens were measured with the TNA assay in support of the clinical study of the RVEc vaccine. The optimal amount of ricin toxin, EL4 cells, and concentration of standards used in the assay system was established to minimize false-negative and false-positive results of serum specimens from the nonclinical and clinical studies of RVEc. The testing conditions were adjusted to optimize assay performance. The colorimetric TNA assay replaced a radioactive TNA assay previously used in the ricin vaccine studies.

  5. A simple colorimetric assay for detection of amplified Mycobacterium leprae DNA

    NARCIS (Netherlands)

    van der Vliet, G. M.; de Wit, M. Y.; Klatser, P. R.

    1993-01-01

    A colorimetric assay for the detection of PCR-products is described. The assay is based on amplification of DNA in the presence of digoxigenin-dUTP. After immobilization of the PCR products to a microtitre plate, amplified DNA could be detected colorimetrically. The sensitivity of this colorimetric

  6. Molecular basis of indomethacin-human serum albumin interaction

    DEFF Research Database (Denmark)

    Trivedi, V D; Vorum, H; Honoré, B

    1999-01-01

    Studies on the strength and extent of binding of the non-steroidal anti-inflammatory drug indomethacin to human serum albumin (HSA) have provided conflicting results. In the present work, the serum-binding of indomethacin was studied in 55 mM sodium phosphate buffer (pH 7.0) at 28 degrees C, by u...

  7. Nanoparticles of Conjugated Methotrexate-Human Serum Albumin: Preparation and Cytotoxicity Evaluations

    Directory of Open Access Journals (Sweden)

    Azade Taheri

    2011-01-01

    Full Text Available Methotrexate-human serum albumin conjugates were developed by a simple carbodiimide reaction. Methotrexate-human serum albumin conjugates were then crosslinked with 1-ethyl-3-(3-dimethylaminopropyl carbodiimide HCl (EDC to form nanoparticles. The size of nanoparticles determined by laser light scattering and TEM was between 90–150 nm. Nanoparticles were very stable at physiologic conditions (PBS pH 7.4, 37∘C and after incubation with serum. The effect of amount of EDC used for crosslinking on the particle size and free amino groups of nanoparticles was examined. The amount of crosslinker showed no significant effect on the size of nanoparticles but free amino groups of nanoparticles were decreased by increasing the crosslinker. The physicochemical interactions between methotrexate and human serum albumin were investigated by differential scanning calorimetry (DSC. Nanoparticles were more cytotoxic on T47D cells compared to free methotrexate. Moreover, methotrexate-human serum albumin nanoparticles decreased the IC50 value of methotrexate on T47D cells in comparison with free methotrexate.

  8. Nanoparticles of Conjugated Methotrexate-Human Serum Albumin: Preparation and Cytotoxicity Evaluations

    International Nuclear Information System (INIS)

    Taheri, A.; Atyabi, F.; Nouri, F.S.; Ahadi, F.; Derakhshan, M.A.; Dinarvand, R.; Atyabi, F.; Ghahremani, M.H.; Ostad, S.N.; Dinarvand, R.; Amini, M.; Ghahremani, M.H.; Ostad, S.N.; Mansoori, P.

    2011-01-01

    Methotrexate-human serum albumin conjugates were developed by a simple carbodiimide reaction. Methotrexate-human serum albumin conjugates were then crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide HCl (EDC) to form nanoparticles. The size of nanoparticles determined by laser light scattering and TEM was between 90 150 nm. Nanoparticles were very stable at physiologic conditions (PBS pH 7.4, 37 degree C) and after incubation with serum. The effect of amount of EDC used for crosslinking on the particle size and free amino groups of nanoparticles was examined. The amount of cross linker showed no significant effect on the size of nanoparticles but free amino groups of nanoparticles were decreased by increasing the cross linker. The physicochemical interactions between methotrexate and human serum albumin were investigated by differential scanning calorimetry (DSC). Nanoparticles were more cytotoxic on T 47 D cells compared to free methotrexate. Moreover, methotrexate-human serum albumin nanoparticles decreased the C50 value of methotrexate on T 47 D cells in comparison with free methotrexate.

  9. Blue emitting copper nanoclusters as colorimetric and fluorescent probe for the selective detection of bilirubin

    Science.gov (United States)

    R. S., Aparna; J. S., Anjali Devi; John, Nebu; Abha, K.; S. S., Syamchand; George, Sony

    2018-06-01

    Hurdles to develop point of care diagnostic methods restrict the translation of progress in the health care sector from bench side to bedside. In this article a simple, cost effective fluorescent as well as colorimetric nanosensor was developed for the early and easy detection of hyperbilirubinemia. A stable, water soluble bovine serum albumin stabilised copper nanocluster (BSA CuNC) was used as the fluorescent probe which exhibited strong blue emission (404 nm) upon 330 nm excitation. The fluorescence of the BSA CuNC can be effectively quenched by the addition of bilirubin by the formation of copper-bilirubin complex. Meanwhile the copper-bilirubin complex resulted in an observable colour change from pale violet to green facilitating colorimetric detection. The prepared sensor displayed good selectivity and sensitivity over other co-existing molecules, and can be used for quantifying bilirubin with a detection limit down to 257 fM. Additionally, the as-prepared probe was coated on a paper strip to develop a portable paper strip sensor of bilirubin. Moreover, the method was successfully applied in real sample analysis and obtained promising result.

  10. Radiocompetitive estimation of 25-hydroxyvitamin D human serum

    International Nuclear Information System (INIS)

    Guillemant, S.; Kremer, R.

    1978-01-01

    A radiocompetitive estimation of 25-hydroxyvitamin D in human serum is described. After extraction, a stage of purification by chromatography on a Sephadex LH 20 column permits separation of 25-hydroxyvitamin D from Vitamin D and other metabolites. The reaction of radiocompetition uses as tracer tritialed 25-hydroxycholecalciferol and as source of binding protein, rat renal cytosol. The characteristics of the binding protein and the presence in human plasma of significant quantities of 24,25-dihydroxyvitamin D render necesssary the chromatographic stage. This technic permits one to measure simply and specifically 25-hydroxyvitamin D in the human serum, of which normal levels (average + - standard deviation) are 12.88 + - 5.42 μg/l (3.2.10 -8 + - 1.35.10 -8 mol/l) [fr

  11. A novel colorimetric aptasensor for ultrasensitive detection of cocaine based on the formation of three-way junction pockets on the surfaces of gold nanoparticles.

    Science.gov (United States)

    Abnous, Khalil; Danesh, Noor Mohammad; Ramezani, Mohammad; Taghdisi, Seyed Mohammad; Emrani, Ahmad Sarreshtehdar

    2018-08-22

    Herein, a novel colorimetric aptasensor was introduced for detection of cocaine based on the formation of three-way junction pockets on the surfaces of gold nanoparticles (AuNPs) and the catalytic activity of the surfaces of AuNPs. Simplicity and detection of cocaine in a short time (only 35 min) are some of the unique features of the proposed sensing strategy. In the presence of cocaine, triple-fragment aptamer (TFA) forms on the surfaces of AuNPs, leading to a significant decrease of the catalytic activity of AuNPs and the color of samples remains yellow. In the absence of target, TFA does not form on the surfaces of AuNPs and 4-Nitrophenol, as a colorimetric agent, has more access to the surfaces of AuNPs, resulting in the reduction of 4-Nitrophenol and the color of sample changes from yellow to colorless. The sensing strategy showed good specificity, a limit of detection (LOD) of 440 pM and a dynamic range over 2-100 nM. The sensing method was also successfully applied to detect cocaine in spiked human serum samples with recovery of 94.71-98.63%. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Human gut microbes impact host serum metabolome and insulin sensitivity

    DEFF Research Database (Denmark)

    Pedersen, Helle Krogh; Gudmundsdottir, Valborg; Nielsen, Henrik Bjørn

    2016-01-01

    Insulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin-resistant individ......Insulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin......-resistant individuals is characterized by increased levels of branched-chain amino acids (BCAAs), which correlate with a gut microbiome that has an enriched biosynthetic potential for BCAAs and is deprived of genes encoding bacterial inward transporters for these amino acids. Prevotella copri and Bacteroides vulgatus...

  13. A novel colorimetric assay for rapid detection of cysteine and Hg²⁺ based on gold clusters.

    Science.gov (United States)

    Wang, Yi-Wei; Tang, Shurong; Yang, Huang-Hao; Song, Hongbo

    2016-01-01

    Inhibition and recovery of the catalytic activity of bovine serum albumin-capped gold nanoclusters (BSA-AuNCs) is observed for the first time by introduction of cysteine and Hg(2+). The prepared BSA-AuNCs possess highly intrinsic peroxidase-like activity. It can catalyze the oxidation of 3, 3, 5, 5-tetramethylbenzidine by H2O2 to produce a blue colored product. Based on this phenomenon, a new colorimetric assay for rapid, selective and sensitive detection of cysteine and Hg(2+) in aqueous solution has been demonstrated. The interaction process between target molecule and BSA-AuNCs is very fast, so that the whole test can be completed within ten minutes. Moreover, the fabricated colorimetric sensor is simple and cost-effective, without the need of nucleic acid based recognition element and complicated washing, separation and labeling process, thus holds great promise for routine analysis of cysteine and Hg(2+) in real samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Radioimmunoassay for prostatic acid phosphatase in human serum. Methodologic aspects

    Energy Technology Data Exchange (ETDEWEB)

    Pradalier, N; Canal, P; Pujol, A; Fregevu, Y [Groupe de Recherches du Centre Claudius-Regaud, Toulouse (France); Soula, G [Faculte des Sciences Pharmaceutiques, Toulouse (France)

    1982-01-01

    We propose a double antibody radioimmunoassay for human prostatic acid phosphatase (PAP) in serum for diagnosis and management of prostatic adenocarcinoma under treatment. The antigen is purified from human prostatic fluid by a gel-filtration on Sephadex G 100 followed by affinity chromatography on Con A Sepharose. A specific antibody is raised in rabbits and purified by immunoadsorption with a female serum. The described technique offers both radioisotopic sensibility and immunologic specificity. Physiological values determined in the serum of 125 healthy males are below 2 ng/ml. No significative differences are observed with age. The proposed technique also shows significant differences between values evaluated for benign prostatic hyperplasia and prostatic adenocarcinoma.

  15. Isolation of human anti-serum albumin Fab antibodies with an extended serum-half life.

    Science.gov (United States)

    Kang, Hyeon-Ju; Kim, Hye-Jin; Cha, Sang-Hoon

    2016-01-01

    The serum albumin (SA) has been exploited to generate long-acting biotherapeutics by taking advantage of the FcRn-mediated recycling mechanism in a direct or an indirect way. Since Fab fragments have been proven to be clinically safe for human usage, we assumed that human anti-SA Fab antibodies could have a great potential as a carrier molecule to extend the serum half-life of therapeutic proteins. We, herein, had attempted to isolate anti-SA Fab antibodies from HuDVFab-8L antibody library via a phage display technology, and identified eight discrete human Fab antibodies. One of the Fab antibodies, SL335, showed the strongest binding reactivity to human SA with nM range of affinity at both pH 6 and pH 7.4, and cross-reacted to SAs from various species including rat, mouse, canine and monkey. The in vivo pharmacokinetic assay using a rat model indicated that SL335 has approximately 10 fold longer serum half-life and 26 to 44-fold increase in AUC0 → ∞ compared to the negative control Fab molecule in both intravenous and subcutaneous administrations. Knowing that Fabs have proven to be safe in clinics for a long time, SL335 seems to have a great potential in generating long-acting protein drugs by tagging effector molecules with either chemical conjugation or genetic fusion. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Determining serum bicarbonate; a simple syringe titrator and colorimeter.

    Science.gov (United States)

    BOONE, C W; FIELD, J B

    1953-12-01

    The use of a tuberculin syringe as a burette has made possible an easy bedside technique for the determination of serum bicarbonate. By combining it with the use of a simple colorimeter, a relatively untrained person can do numerous bicarbonate determinations with a high degree of accuracy. The same technique also lends itself to other colorimetric clinical procedures such as determination of gastric acidity.

  17. DETERMINING SERUM BICARBONATE—A Simple Syringe Titrator and Colorimeter

    Science.gov (United States)

    Boone, Charles W.; Field, John B.

    1953-01-01

    The use of a tuberculin syringe as a burette has made possible an easy bedside technique for the determination of serum bicarbonate. By combining it with the use of a simple colorimeter, a relatively untrained person can do numerous bicarbonate determinations with a high degree of accuracy. The same technique also lends itself to other colorimetric clinical procedures such as determination of gastric acidity. PMID:13106724

  18. Human serum amyloid genes--molecular characterization

    International Nuclear Information System (INIS)

    Sack, G.H.; Lease, J.J.

    1986-01-01

    Three clones containing human genes for serum amyloid A protein (SAA) have been isolated and characterized. Each of two clones, GSAA 1 and 2 (of 12.8 and 15.9 kilobases, respectively), contains two exons, accouting for amino acids 12-58 and 58-103 of mature SAA; the extreme 5' termini and 5' untranslated regions have not yet been defined but are anticipated to be close based on studies of murine SAA genes. Initial amino acid sequence comparisons show 78/89 identical residues. At 4 of the 11 discrepant residues, the amino acid specified by the codon is the same as the corresponding residue in murine SAA. Identification of regions containing coding regions has permitted use of selected subclones for blot hybridization studies of larger human SAA chromosomal gene organization. The third clone, GSAA 3 also contains SAA coding information by DNA sequence analysis but has a different organization which has not yet been fully described. We have reported the isolation of clones of human DNA hybridizing with pRS48 - a plasmid containing a complementary DNA (cDNA) clone for murine serum amyloid A (SAA; 1, 2). We now present more detailed data confirming the identity and defining some of the organizational features of these clones

  19. Binding of radioiodinated human. beta. -endorphin to serum proteins from rats and humans, determined by several methods

    Energy Technology Data Exchange (ETDEWEB)

    Sato, H.; Sugiyama, Y.; Sawada, Y.; Iga, T.; Hanano, M.

    1985-10-07

    Binding of immunoreactive radioiodinated human ..beta..-endorphin (/sup 125/I-..beta..-EP) to rat serum was demonstrated by gel filtration of /sup 125/I-..beta..-EP in pooled rat serum on Sephadex G-200. Two radioactive peaks associated with proteins eluted from the column. The first peak eluted at the void volume containing lipoproteins, ..cap alpha../sub 2/- and ..beta../sub 2/-macroglobulins, and the second peak at the fraction of albumin. Binding of /sup 125/I-..beta..-EP to albumin was directly proved by gel filtration of /sup 125/I-..beta..-EP in buffer containing 4% human serum albumin on Sephadex G-200. Equilibrium dialysis was not applicable to investigating the interaction of /sup 125/I-..beta..-EP with serum proteins, because of the intense nonspecific adsorption to the semi-permeable membrane and the degradation of the peptide during dialysis. Therefore, in order to quantitatively evaluate the binding of /sup 125/I-..beta..-EP in sera from rats and humans, the authors utilized four other methods (ultrafiltration, charcoal adsorption, polyethylene glycol precipitation and equilibrium gel filtration). These methods corresponded well with each other and indicated 35-44% binding of /sup 125/I-..beta..-EP in rat serum. Binding of /sup 125/I-..beta..-EP in normal human serum was 36%, determined by ultrafiltration. Serum protein binding of /sup 125/I-..beta..-EP was concentration independent over the concentration range studied (1-1000 nM). 23 references, 4 figures, 1 table.

  20. Combined Colorimetric and Gravimetric CMUT Sensor for Detection of Phenylacetone

    DEFF Research Database (Denmark)

    Mølgaard, Mathias Johannes Grøndahl; Laustsen, Milan; Thygesen, Ida Lysgaard

    2017-01-01

    The detection of phenylacetone is of interest as it is a common precursor for the synthesis of (meth)amphetamine. Resonant gravimetric sensors can be used to detect the mass and hereby the concentration of a gas while colorimetric arrays typically have an exceptional selectivity to the target...... analyte if the right colorimetric dyes are chosen. We present a sensor system consisting of a Capacitive Micromachined Ultrasonic Transducer (CMUT) and a colorimetric array for detection of phenylacetone. The CMUT is used as a resonant gravimetric gas sensor where the resonance frequency shift due to mass...

  1. Interaction of Citrinin with Human Serum Albumin

    Directory of Open Access Journals (Sweden)

    Miklós Poór

    2015-12-01

    Full Text Available Citrinin (CIT is a mycotoxin produced by several Aspergillus, Penicillium, and Monascus species. CIT occurs worldwide in different foods and drinks and causes health problems for humans and animals. Human serum albumin (HSA is the most abundant plasma protein in human circulation. Albumin forms stable complexes with many drugs and xenobiotics; therefore, HSA commonly plays important role in the pharmacokinetics or toxicokinetics of numerous compounds. However, the interaction of CIT with HSA is poorly characterized yet. In this study, the complex formation of CIT with HSA was investigated using fluorescence spectroscopy and ultrafiltration techniques. For the deeper understanding of the interaction, thermodynamic, and molecular modeling studies were performed as well. Our results suggest that CIT forms stable complex with HSA (logK ~ 5.3 and its primary binding site is located in subdomain IIA (Sudlow’s Site I. In vitro cell experiments also recommend that CIT-HSA interaction may have biological relevance. Finally, the complex formations of CIT with bovine, porcine, and rat serum albumin were investigated, in order to test the potential species differences of CIT-albumin interactions.

  2. Comparison between human serum and Albuminar-20 (TM) supplement for in-vitro fertilization.

    Science.gov (United States)

    Staessen, C; Van den Abbeel, E; Carlé, M; Khan, I; Devroey, P; Van Steirteghem, A C

    1990-04-01

    Patient or fetal cord serum is commonly used as a protein supplement to culture media used in in-vitro fertilization (IVF). To eliminate the variability and possible hazards related to the use of human serum, a well-defined protein supplement, Albuminar-20 (Armour Pharmaceutical Cy) was evaluated as a substitute for serum. Prior to its application in the human, Earle's culture media supplemented with 0.5% (w/v) bovine serum albumin, 8% (v/v) decomplemented patient serum or 2.25% (v/v) Albuminar-20 were compared in a mouse bioassay. For the three different conditions, the percentages of blastocysts formed after 120 h in-vitro culture were respectively 91.2, 85.2 and 87.8% (NS). In the human IVF, a controlled comparison was performed from October to December 1988, between Earle's medium supplemented with patients' serum or Albuminar-20. When oocytes and spermatozoa were cultured in these two media, the fertilization rates were similar, 58.9% in human serum versus 59.4% in Albuminar-20. After further culture, the morphological quality of the cleaved embryos was better in the embryos cultured in Albuminar-20. The higher pregnancy rate in Albuminar-20 was correlated with the better morphological appearance of the embryos and their more advanced cleavage stage at the time of transfer. Therefore, Albuminar-20 can be considered as a suitable protein supplement in human IVF.

  3. Radioimmunoassay for prostatic acid phosphatase in human serum. Methodologic aspects

    International Nuclear Information System (INIS)

    Pradalier, N.; Canal, P.; Pujol, A.; Fregevu, Y.; Soula, G.

    1982-01-01

    We propose a double antibody radioimmunoassay for human prostatic acid phosphatase (PAP) in serum for diagnosis and management of prostatic adenocarcinoma under treatment. The antigen is purified from human prostatic fluid by a gel-filtration on Sephadex G 100 followed by affinity chromatography on Con A Sepharose. A specific antibody is raised in rabbits and purified by immunoadsorption with a female serum. The described technique offers both radioisotopic sensibility and immunologic specificity. Physiological values determined in the serum of 125 healthy males are below 2 ng/ml. No significative differences are observed with age. The proposed technique also shows significant differences between values evaluated for benign prostatic hyperplasia and prostatic adenocarcinoma [fr

  4. The stability of complement-mediated bactericidal activity in human serum against Salmonella.

    Directory of Open Access Journals (Sweden)

    Colette M O'Shaughnessy

    Full Text Available The complement cascade includes heat-labile proteins and care is required when handling serum in order to preserve its functional integrity. We have previously used a whole human serum bactericidal assay to show that antibody and an intact complement system are required in blood for killing of invasive isolates of Salmonella. The aim of the present study was to evaluate the conditions under which human serum can be stored and manipulated while maintaining complement integrity. Serum bactericidal activity against Salmonella was maintained for a minimum of 35 days when stored at 4°C, eight days at 22°C and 54 hours at 37°C. Up to three freeze-thaw cycles had no effect on the persistence of bactericidal activity and hemolytic complement assays confirmed no effect on complement function. Delay in the separation of serum for up to four days from clotted blood stored at 22°C did not affect bactericidal activity. Dilution of serum resulted in an increased rate of loss of bactericidal activity and so serum should be stored undiluted. These findings indicate that the current guidelines concerning manipulation and storage of human serum to preserve complement integrity and function leave a large margin for safety with regards to bactericidal activity against Salmonella. The study provides a scheme for determining the requirements for serum handling in relation to functional activity of complement in other systems.

  5. Human platelet lysate: Replacing fetal bovine serum as a gold standard for human cell propagation?

    Science.gov (United States)

    Burnouf, Thierry; Strunk, Dirk; Koh, Mickey B C; Schallmoser, Katharina

    2016-01-01

    The essential physiological role of platelets in wound healing and tissue repair builds the rationale for the use of human platelet derivatives in regenerative medicine. Abundant growth factors and cytokines stored in platelet granules can be naturally released by thrombin activation and clotting or artificially by freeze/thaw-mediated platelet lysis, sonication or chemical treatment. Human platelet lysate prepared by the various release strategies has been established as a suitable alternative to fetal bovine serum as culture medium supplement, enabling efficient propagation of human cells under animal serum-free conditions for a multiplicity of applications in advanced somatic cell therapy and tissue engineering. The rapidly increasing number of studies using platelet derived products for inducing human cell proliferation and differentiation has also uncovered a considerable variability of human platelet lysate preparations which limits comparability of results. The main variations discussed herein encompass aspects of donor selection, preparation of the starting material, the possibility for pooling in plasma or additive solution, the implementation of pathogen inactivation and consideration of ABO blood groups, all of which can influence applicability. This review outlines the current knowledge about human platelet lysate as a powerful additive for human cell propagation and highlights its role as a prevailing supplement for human cell culture capable to replace animal serum in a growing spectrum of applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Effects of Macromolecular Crowding on Human Adipose Stem Cell Culture in Fetal Bovine Serum, Human Serum, and Defined Xeno-Free/Serum-Free Conditions.

    Science.gov (United States)

    Patrikoski, Mimmi; Lee, Michelle Hui Ching; Mäkinen, Laura; Ang, Xiu Min; Mannerström, Bettina; Raghunath, Michael; Miettinen, Susanna

    2017-01-01

    Microenvironment plays an important role for stem cell proliferation and differentiation. Macromolecular crowding (MMC) was recently shown to assist stem cells in forming their own matrix microenvironment in vitro. The ability of MMC to support adipose stem cell (ASC) proliferation, metabolism, and multilineage differentiation was studied under different conditions: fetal bovine serum- (FBS-) and human serum- (HS-) based media and xeno- and serum-free (XF/SF) media. Furthermore, the immunophenotype of ASCs under MMC was evaluated. The proliferative capacity of ASCs under MMC was attenuated in each condition. However, osteogenic differentiation was enhanced under MMC, shown by increased deposition of mineralized matrix in FBS and HS cultures. Likewise, significantly greater lipid droplet accumulation and increased collagen IV deposition indicated enhanced adipogenesis under MMC in FBS and HS cultures. In contrast, chondrogenic differentiation was attenuated in ASCs expanded under MMC. The ASC immunophenotype was maintained under MMC with significantly higher expression of CD54. However, MMC impaired metabolic activity and differentiation capacity of ASCs in XF/SF conditions. Both the supportive and inhibitory effects of MMC on ASC are culture condition dependent. In the presence of serum, MMC maintains ASC immunophenotype and enhances adipogenic and osteogenic differentiation at the cost of reduced proliferation.

  7. Oxidized Lipoprotein as a Major Vessel Cell Proliferator in Oxidized Human Serum.

    Directory of Open Access Journals (Sweden)

    Yoshiro Saito

    Full Text Available Oxidative stress is correlated with the incidence of several diseases such as atherosclerosis and cancer, and oxidized biomolecules have been determined as biomarkers of oxidative stress; however, the detailed molecular relationship between generated oxidation products and the promotion of diseases has not been fully elucidated. In the present study, to clarify the role of serum oxidation products in vessel cell proliferation, which is related to the incidence of atherosclerosis and cancer, the major vessel cell proliferator in oxidized human serum was investigated. Oxidized human serum was prepared by free radical exposure, separated using gel chromatography, and then each fraction was added to several kinds of vessel cells including endothelial cells and smooth muscle cells. It was found that a high molecular weight fraction in oxidized human serum specifically induced vessel cell proliferation. Oxidized lipids were contained in this high molecular weight fraction, while cell proliferation activity was not observed in oxidized lipoprotein-deficient serum. Oxidized low-density lipoproteins induced vessel cell proliferation in a concentration-dependent manner. Taken together, these results indicate that oxidized lipoproteins containing lipid oxidation products function as a major vessel cell proliferator in oxidized human serum. These findings strongly indicate the relevance of determination of oxidized lipoproteins and lipid oxidation products in the diagnosis of vessel cell proliferation-related diseases such as atherosclerosis and cancer.

  8. Interaction of amphiphilic drugs with human and bovine serum albumins.

    Science.gov (United States)

    Khan, Abbul Bashar; Khan, Javed Masood; Ali, Mohd Sajid; Khan, Rizwan Hasan; Kabir-Ud-Din

    2012-11-01

    To know the interaction of amphiphilic drugs nortriptyline hydrochloride (NOT) and promazine hydrochloride (PMZ) with serum albumins (i.e., human serum albumin (HSA) and bovine serum albumin (BSA)), techniques of UV-visible, fluorescence, and circular dichroism (CD) spectroscopies are used. The binding affinity is more in case of PMZ with both the serum albumins. The quenching rate constant (k(q)) values suggest a static quenching process for all the drug-serum albumin interactions. The UV-visible results show that the change in protein conformation of PMZ-serum albumin interactions are more prominent as compared to NOT-serum albumin interactions. The CD results also explain the conformational changes in the serum albumins on binding with the drugs. The increment in %α-helical structure is slightly more for drug-BSA complexes as compared to drug-HSA complexes. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Colorimetric evaluation of irradiated red beet roots

    International Nuclear Information System (INIS)

    Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Fabbri, Adriana D.T.; Sagretti, Juliana M.A.; Hirashima, Fabiana K.; Sabato, Susy F.

    2013-01-01

    The red beetroot contain antioxidant and anticancer activity and have been consumed all over the world. In order to increase the consumption of beetroot the food industry has created a practical alternative, a beetroot shaped like a small ball, minimally processed with the convenience in meal preparation. Food irradiation is in consonance with the proposal to increase the consumption of beetroot whilst maintaining quality and product safety. The aim of this study was to analyze changes in colorimetric properties in beetroot after the irradiation process. Samples of minimally processed beetroot were purchased at a local supermarket. The samples were exposed to gamma rays with doses of 1.0kG y , 2.0kG y , 3.0kG y and 4.0 kG y and were stored at 5 deg C. Colorimetric characteristics were analyzed such as L * , a * , b * , C * , h * , δE and WI. The results of the colorimetric evaluation showed no significant difference among the samples. The authors concluded that the treatment with low doses of gamma radiation keeps the quality of beetroot. (author)

  10. Capillarity-based preparation system for optical colorimetric sensor arrays.

    Science.gov (United States)

    Luo, Xiao-Gang; Yi, Xin; Bu, Xiang-Nan; Hou, Chang-Jun; Huo, Dan-Qun; Yang, Mei; Fa, Huan-Bao; Lei, Jin-Can

    2017-03-01

    In recent years, optical colorimetric sensor arrays have demonstrated beneficial features, including rapid response, high selectivity, and high specificity; as a result, it has been extensively applied in food inspection and chemical studies, among other fields. There are instruments in the current market available for the preparation of an optical colorimetric sensor array, but it lacks the corresponding research of the preparation mechanism. Therefore, in connection with the main features of this kind of sensor array such as consistency, based on the preparation method of contact spotting, combined with a capillary fluid model, Washburn equation, Laplace equation, etc., this paper develops a diffusion model of an optical colorimetric sensor array during its preparation and sets up an optical colorimetric sensor array preparation system based on this diffusion model. Finally, this paper compares and evaluates the sensor arrays prepared by the system and prepared manually in three aspects such as the quality of array point, response of array, and response result, and the results show that the performance index of the sensor array prepared by a system under this diffusion model is better than that of the sensor array of manual spotting, which meets the needs of the experiment.

  11. PRINCIPLE OF VALIDATION OF MULTILEVEL RGB COLORIMETRIC SYSTEMS OF REMOTE SENSING

    Directory of Open Access Journals (Sweden)

    Lala Rustam Bekirova

    2013-12-01

    Full Text Available The possibility of development of two-level RGB colorimetric systems of remote sensing is analyzed. The principle of validation in multi-level RGB colorimetric systems taking into account the effect of metamerizm is formulated

  12. Measurement of theophylline in human serum

    International Nuclear Information System (INIS)

    Stetten, O. von; Zech, K.

    1980-01-01

    A radioimmunological (RIA-matsup(R) Theophylline) and a HPLC method for the determination of theophylline concentrations in human serum are compared. HPLC as most specific and precise method is not suitable for greater numbers of analyses due to time needed for chromatography. Theophylline-RIA yields excellent results regarding precision, specificity and recovery with excellent correlation and considerable time savings compared to HPLC. (orig.) [de

  13. Serum ferritin, serum nitric oxide, and cognitive function in pediatric thalassemia major

    Directory of Open Access Journals (Sweden)

    Septiana Nur Qurbani

    2017-06-01

    Full Text Available Background Hemolysis and repeated blood transfusions in children with thalassemia major cause iron overload in various organs, including the brain, and may lead to neurodegeneration. Hemolysis also causes decreased levels of nitric oxide, which serves as a volume transmitter and slow dynamic modulation, leading to cognitive impairment. Objective To assess for correlations between serum ferritin as well as nitric oxide levels and cognitive function in children with thalassemia major.  Methods This analytical study with cross-sectional design on 40 hemosiderotic thalassemia major patients aged 6−14 years, was done at the Thalassemia Clinic in Dr. Hasan Sadikin Hospital, Bandung, West Java, from May to June 2015. Serum ferritin measurements were performed by an electrochemiluminescence immunoassay; serum nitric oxide was assayed by a colorimetric procedure based on Griess reaction; and cognitive function was assessed by the Wechsler Intelligence Scale for Children test. Statistical analysis was done using Spearman’s Rank correlation, with a significance value of 0.05. Results Abnormal values in verbal, performance, and full scale IQ were found in 35%, 57.5% and 57.5%, respectively. Serum nitric oxide level was significantly correlated with performance IQ (P=0.022, but not with verbal IQ (P=0.359 or full scale IQ (P=0.164. There were also no significant correlations between serum ferritin level and full scale, verbal, or performance IQ (P=0.377, 0.460, and 0.822, respectively. Conclusion Lower serum nitric oxide level is significantly correlated to lower cognitive function, specifically in the performance IQ category. However, serum ferritin level has no clear correlation with cognitive function.

  14. Radioimmunoassay of creatine kinase isoenzymes in human serum: isoenzyme MM

    International Nuclear Information System (INIS)

    Van Steirteghem, A.C.; Zweig, M.H.; Schechter, A.N.

    1978-01-01

    Measurement of the mass concentration of serum enzymes by radioimmunoassay provides direct quantitation of specific isoenzymes and may be less subject to some of the limitations of traditional assay procedures for enzymes. We describe the development of a sensitive and specific radioimmunoassay for the muscle isoenzyme of creatine kinase, CK-MM, in human serum. CK-MM, purified from human skeletal muscle, was used to raise high-titer antisera and for iodination by the Chloramine T method. The radioimmunoassay required 50 μl of sample, utilized a double-antibody separation method, and was completed in 24 h. Cross reactivity with CK-BB was virtually zero, 3 to 17 percent with CK-MB. The mass concentration of CK-MM in the serum of healthy subjects ranged from 36 to 1668 μg/liter and correlated closely with total CK enzymatic activity. Serum concentrations of CK-MM from casually selected patients correlated less well with total CK enzymatic activity, suggesting the existence of other CK isoenzymes or the presence of inactive forms

  15. Colorimetric evaluation of irradiated red beet roots

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Fabbri, Adriana D.T.; Sagretti, Juliana M.A.; Hirashima, Fabiana K.; Sabato, Susy F., E-mail: thaisecfnunes@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The red beetroot contain antioxidant and anticancer activity and have been consumed all over the world. In order to increase the consumption of beetroot the food industry has created a practical alternative, a beetroot shaped like a small ball, minimally processed with the convenience in meal preparation. Food irradiation is in consonance with the proposal to increase the consumption of beetroot whilst maintaining quality and product safety. The aim of this study was to analyze changes in colorimetric properties in beetroot after the irradiation process. Samples of minimally processed beetroot were purchased at a local supermarket. The samples were exposed to gamma rays with doses of 1.0kG{sub y}, 2.0kG{sub y}, 3.0kG{sub y} and 4.0 kG{sub y} and were stored at 5 deg C. Colorimetric characteristics were analyzed such as L{sup *}, a{sup *}, b{sup *}, C{sup *}, h{sup *}, δE and WI. The results of the colorimetric evaluation showed no significant difference among the samples. The authors concluded that the treatment with low doses of gamma radiation keeps the quality of beetroot. (author)

  16. Ultrasensitive colorimetric detection of Cu2+ ion based on catalytic oxidation of L-cysteine.

    Science.gov (United States)

    Yin, Kun; Li, Bowei; Wang, Xiaochun; Zhang, Weiwei; Chen, Lingxin

    2015-02-15

    As an essential element, copper ion (Cu(2+)) plays important roles in human beings for its participation in diverse metabolic processes as a cofactor and/or a structural component of enzymes. However, excessive uptake of Cu(2+) ion gives rise to the risk of certain diseases. So, it is important to develop simple ways to monitor and detect Cu(2+) ion. In this study, a simple, facile colorimetric sensor for the ultrasensitive determination of Cu(2+) ion was developed based on the following principle: L-cysteine and 1-chloro-2,4-dinitrobenzene (CDNB) could be conjugated to form the yellow product 2,4-dinitrophenylcysteine (DNPC), which was measurable at 355nm; however, upon addition of Cu(2+) ion, the absorbance of DNPC would be decreased owing to the Cu(2+) ion catalytic oxidation of L-cysteine to L-cystine in the presence of O2. Thus, the colorimetric detection of Cu(2+) ion could be achieved. The optimal pH, buffer, temperature and incubation time for the colorimetric sensor were obtained of pH 6.8 in 0.1M HEPES solution, 90 °C and 50 min, respectively. A good linearity within the range of 0.8-10 nM (r = 0.996) was attained, with a high detectability up to 0.5nM. Analyses of Cu(2+) ion in drinking water, lake water, seawater and biological samples were carried out and the method performances were found to agree well with that obtained by ICP-MS. The developed simple colorimetric sensor proved applicable for Cu(2+) ion determination in real samples with high sensitivity and selectivity. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Emergency First Responders' Experience with Colorimetric Detection Methods

    Energy Technology Data Exchange (ETDEWEB)

    Sandra L. Fox; Keith A. Daum; Carla J. Miller; Marnie M. Cortez

    2007-10-01

    Nationwide, first responders from state and federal support teams respond to hazardous materials incidents, industrial chemical spills, and potential weapons of mass destruction (WMD) attacks. Although first responders have sophisticated chemical, biological, radiological, and explosive detectors available for assessment of the incident scene, simple colorimetric detectors have a role in response actions. The large number of colorimetric chemical detection methods available on the market can make the selection of the proper methods difficult. Although each detector has unique aspects to provide qualitative or quantitative data about the unknown chemicals present, not all detectors provide consistent, accurate, and reliable results. Included here, in a consumer-report-style format, we provide “boots on the ground” information directly from first responders about how well colorimetric chemical detection methods meet their needs in the field and how they procure these methods.

  18. Human autologous serum as a substitute for fetal bovine serum in human Schwann cell culture.

    Directory of Open Access Journals (Sweden)

    Parisa Goodarzi

    2014-04-01

    Full Text Available Nowadays, cell -based and tissue engineered products have opened new horizons in treatment of incurable nervous system disorders. The number of studies on the role of Schwann cells (SC in treating nervous disorders is higher than other cell types. Different protocols have been suggested for isolation and expansion of SC which most of them have used multiple growth factors, mitogens and fetal bovine sera (FBS in culture medium. Because of potential hazards of animal-derived reagents, this study was designed to evaluate the effect of replacing FBS with human autologous serum (HAS on SC's yield and culture parameters. Samples from 10 peripheral nerve biopsies were retrieved and processed under aseptic condition. The isolated cells cultured in FBS (1st group or autologous serum (2nd group. After primary culture the cells were seeded at 10000 cell/cm2 in a 12 wells cell culture plate for each group. At 100% confluency, the cell culture parameters (count, viability, purity and culture duration of 2 groups were compared using paired t-test. The average donors' age was 35.80 (SD=13.35 and except for 1 sample the others cultured successfully. In first group, the averages of cell purity, viability and culture duration were 97% (SD=1.32, 97/33% (SD=1.22 and 11.77 (SD=2.58 days respectively. This parameters were 97.33% (SD=1.00, 97.55% (SD=1.33 and 10.33 days (SD=1.65 in second group. The difference of cell count, purity and viability were not significant between 2 groups (P>0.05. The cells of second group reached to 100% confluency in shorter period of time (P=0.03. The results of this study showed that autologous serum can be a good substitute for FBS in human SC culture. This can reduce the costs and improve the safety of cell product for clinical application.

  19. Kinetics of human serum amyloid A

    International Nuclear Information System (INIS)

    Rosenthal, C.J.; Martin, M.E.; Solomon, N.

    1986-01-01

    In order to better understand the pathogenetic role of serum amyloid A (SAA) we studied the kinetics of 131 I radiolabelled pure SAA, extracted from 400 ml serum of a human volunteer. 50 microCi of 131 I SAA and 15 microCi 125 I labelled sodium iodide were administered i.v. on two occasions at 6 month intervals. Serum and plasma samples were collected at 10-20 min intervals x 10, then once daily x 10; lymphocytes were separated from monocytes and granulocytes. Counts per minute of 131 I and 125 I were measured in each sample in the serum, in serum precipitates resulting after addition of a rabbit anti-SAA antibody and of TCA and in various cell subpopulations as well as in the whole urine and TCA precipitated urine from each micturition. The 131 I disappearance curves from the plasma and serum precipitates were semilogarithmically plotted; cumulative 131 I cpm in plasma, cells and urine at various intervals were determined. Body scanning was performed at 2, 16, and 48 h. The results of the two experiments were very similar. The curve of 131 I SAA in plasma TCA precipitates indicated the existence of 4 compartments likely due to uptake of 131 I SAA by some plasma proteins, circulating cells and other tissues; later release from tissues started at 6 h. The 131 I SAA half-life time in these compartments was found to be 35, 170, 255, and 550 min, respectively. Tissue binding of 131 I was also suggested by a rising of the 125 I: 131 I ratio with time and by a 26% release of 131 I in the urine at 15 h which could not account for its plasma disappearance. Scanning, except for 131 I uptake in the spleen at 2 h likely due to blood activity, showed no organ concentration. 92% of the injected 131 I was found in the urine but only 6.2% of 131 I SAA was accounted for in urine precicipitates

  20. Zinc in human serum

    International Nuclear Information System (INIS)

    Kiilerich, S.

    1987-01-01

    The zinc ion is essential for the living organism. Many pathological conditions have been described as a consequence of zinc deficiency. As zinc constitutes less than 0.01 per cent of the body weight, it conventionally belongs to the group of trace elements. The method of atomic absorption spectrophotometry is used to measure the concentration of zinc in serum and urine from healthy persons. The assumptions of the method is discussed. The importance of proteinbinding, diet and the diurnal variation of serum zinc concentration is presented. Serum versus plasma zinc concentration is discussed. Reference serum zinc values from 104 normal subjects are given. Zinc in serum is almost entirely bound to proteins. A preliminary model for the estimation of the distribution of zinc between serum albumin and α 2 -macroglobulin is set up. This estimate has been examined by an ultracentrufugation method. The binding of zinc to a α 2 -macroglobulin in normal persons is appoximately 7 per cent, in patients with cirrhosis of the liver of alcoholic origin approximately 6 per cent, in patients with insulin dependent diabetes mellitus approximately 5 per cent, and in patients with chronic renal failure approximately 2 per cent. It is concluded, therefore, that for clinical purposes it is sufficient to use the concentration of total serum zinc corrected for the concentration of serum albumin. (author)

  1. Expression and characterization of recombinant human serum ...

    African Journals Online (AJOL)

    C-peptide (CP), connecting the A and B chains in proinsulin, has been considered to possess physiological effects in diabetes. In order to prolong the half-life of CP in vivo, a long acting CP analog [human serum albumin (HSA-CP)] was obtained by direct gene fusion of a single-chain CP to HSA and expressed in host ...

  2. Expression and characterization of recombinant human serum ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-14

    Nov 14, 2011 ... C-peptide (CP), connecting the A and B chains in proinsulin, has been considered to possess physiological effects in diabetes. In order to prolong the half-life of CP in vivo, a long acting CP analog. [human serum albumin (HSA-CP)] was obtained by direct gene fusion of a single-chain CP to HSA and.

  3. Mangifera indica L. (Vimang) protection against serum oxidative stress in elderly humans.

    Science.gov (United States)

    Pardo-Andreu, Gilberto L; Philip, Sarah J; Riaño, Annia; Sánchez, Carlos; Viada, Carmen; Núñez-Sellés, Alberto J; Delgado, René

    2006-01-01

    We searched for the protective effect of a natural extract from stem bark of Mangifera indica L. extract (Vimang) on age-related oxidative stress. Healthy subjects were classified in two groups, elderly (>65 years) and young group (Vimang tablets, 300 mg each, before meals) for 60 days. Serum concentration of lipid peroxides, serum peroxidation potential, extracellular superoxide dismutase activity (EC-SOD), glutathione status (GSH, GSSG, GSSG/GSH ratio)) and total antioxidant status (TAS) were determined before (both experimental groups) and 15, 30, and 60 days after treatment (only elderly group). We confirmed the existence of an age-associated oxidative stress in human serum as documented by an age-related increase in serum lipoperoxides and GSSG and a decrease in serum antioxidant capacity and EC-SOD activity. Vimang tablet supplementation increased EC-SOD activity (p Vimang tablets prevent age-associated oxidative stress in elderly humans, which could retard the onset of age-associated disease, improving the quality of life for elderly persons.

  4. Competitive Protein Adsorption of Albumin and Immunoglobulin G from Human Serum onto Polymer Surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Hou, Xiaolin

    2010-01-01

    protein adsorption from diluted human serum solutions with relatively low protein concentrations, but the nonfouling character was weakened when less diluted human serum solutions with higher protein concentrations were used. The observed adsorption trend is independent of adsorption time, indicating...

  5. Serum albumin: accuracy and clinical use.

    Science.gov (United States)

    Infusino, Ilenia; Panteghini, Mauro

    2013-04-18

    Albumin is the major plasma protein and its determination is used for the prognostic assessment of several diseases. Clinical guidelines call for monitoring of serum albumin with specific target cut-offs that are independent of the assay used. This requires accurate and equivalent results among different commercially available methods (i.e., result standardization) through a consistent definition and application of a reference measurement system. This should be associated with the definition of measurement uncertainty goals based on medical relevance of serum albumin to make results reliable for patient management. In this paper, we show that, in the current situation, if one applies analytical goals for serum albumin measurement derived from its biologic variation, the uncertainty budget derived from each step of the albumin traceability chain is probably too high to fulfil established quality levels for albumin measurement and to guarantee the accuracy needed for clinical usefulness of the test. The situation is further worsened if non-specific colorimetric methods are used for albumin measurement as they represent an additional random source of uncertainty. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Photonic Crystal Structures with Tunable Structure Color as Colorimetric Sensors

    Science.gov (United States)

    Wang, Hui; Zhang, Ke-Qin

    2013-01-01

    Colorimetric sensing, which transduces environmental changes into visible color changes, provides a simple yet powerful detection mechanism that is well-suited to the development of low-cost and low-power sensors. A new approach in colorimetric sensing exploits the structural color of photonic crystals (PCs) to create environmentally-influenced color-changeable materials. PCs are composed of periodic dielectrics or metallo-dielectric nanostructures that affect the propagation of electromagnetic waves (EM) by defining the allowed and forbidden photonic bands. Simultaneously, an amazing variety of naturally occurring biological systems exhibit iridescent color due to the presence of PC structures throughout multi-dimensional space. In particular, some kinds of the structural colors in living organisms can be reversibly changed in reaction to external stimuli. Based on the lessons learned from natural photonic structures, some specific examples of PCs-based colorimetric sensors are presented in detail to demonstrate their unprecedented potential in practical applications, such as the detections of temperature, pH, ionic species, solvents, vapor, humidity, pressure and biomolecules. The combination of the nanofabrication technique, useful design methodologies inspired by biological systems and colorimetric sensing will lead to substantial developments in low-cost, miniaturized and widely deployable optical sensors. PMID:23539027

  7. Photonic Crystal Structures with Tunable Structure Color as Colorimetric Sensors

    Directory of Open Access Journals (Sweden)

    Ke-Qin Zhang

    2013-03-01

    Full Text Available Colorimetric sensing, which transduces environmental changes into visible color changes, provides a simple yet powerful detection mechanism that is well-suited to the development of low-cost and low-power sensors. A new approach in colorimetric sensing exploits the structural color of photonic crystals (PCs to create environmentally-influenced color-changeable materials. PCs are composed of periodic dielectrics or metallo-dielectric nanostructures that affect the propagation of electromagnetic waves (EM by defining the allowed and forbidden photonic bands. Simultaneously, an amazing variety of naturally occurring biological systems exhibit iridescent color due to the presence of PC structures throughout multi-dimensional space. In particular, some kinds of the structural colors in living organisms can be reversibly changed in reaction to external stimuli. Based on the lessons learned from natural photonic structures, some specific examples of PCs-based colorimetric sensors are presented in detail to demonstrate their unprecedented potential in practical applications, such as the detections of temperature, pH, ionic species, solvents, vapor, humidity, pressure and biomolecules. The combination of the nanofabrication technique, useful design methodologies inspired by biological systems and colorimetric sensing will lead to substantial developments in low-cost, miniaturized and widely deployable optical sensors.

  8. Polymerized soluble venom--human serum albumin

    International Nuclear Information System (INIS)

    Patterson, R.; Suszko, I.M.; Grammer, L.C.

    1985-01-01

    Extensive previous studies have demonstrated that attempts to produce polymers of Hymenoptera venoms for human immunotherapy resulted in insoluble precipitates that could be injected with safety but with very limited immunogenicity in allergic patients. We now report soluble polymers prepared by conjugating bee venom with human serum albumin with glutaraldehyde. The bee venom-albumin polymer (BVAP) preparation was fractionated on Sephacryl S-300 to have a molecular weight range higher than catalase. 125 I-labeled bee venom phospholipase A was almost completely incorporated into BVAP. Rabbit antibody responses to bee venom and bee venom phospholipase A were induced by BVAP. Human antisera against bee venom were absorbed by BVAP. No new antigenic determinants on BVAP were present as evidenced by absorption of antisera against BVAP by bee venom and albumin. BVAP has potential immunotherapeutic value in patients with anaphylactic sensitivity to bee venom

  9. GM-CSF production from human airway smooth muscle cells is potentiated by human serum

    Directory of Open Access Journals (Sweden)

    Maria B. Sukkar

    2000-01-01

    Full Text Available Recent evidence suggests that airway smooth muscle cells (ASMC actively participate in the airway inflammatory process in asthma. Interleukin–1β (IL–1β and tumour necrosis factor–α (TNF–α induce ASMC to release inflammatory mediators in vitro. ASMC mediator release in vivo, however, may be influenced by features of the allergic asthmatic phenotype. We determined whether; (1 allergic asthmatic serum (AAS modulates ASMC mediator release in response to IL–1β and TNF–α, and (2 IL–1β/TNF–α prime ASMC to release mediators in response to AAS. IL–5 and GMCSF were quantified by ELISA in culture supernatants of; (1 ASMC pre-incubated with either AAS, non-allergic non-asthmatic serum (NAS or MonomedTM (a serum substitute and subsequently stimulated with IL–1β and TNF–α and (2 ASMC stimulated with IL–1β/TNF–α and subsequently exposed to either AAS, NAS or MonomedTM. IL-1g and TNF–α induced GM-CSF release in ASMC pre-incubated with AAS was not greater than that in ASMC pre-incubated with NAS or MonomedTM. IL–1β and TNF–α, however, primed ASMC to release GM-CSF in response to human serum. GM-CSF production following IL–1β/TNF–α and serum exposure (AAS or NAS was significantly greater than that following IL–1β /TNF–α and MonomedTM exposure or IL–1β/TNF–α exposure only. Whilst the potentiating effects of human serum were not specific to allergic asthma, these findings suggest that the secretory capacity of ASMC may be up-regulated during exacerbations of asthma, where there is evidence of vascular leakage.

  10. Radioimmunoassay of haloperidol in human serum: correlation of serum haloperidol with serum prolactin

    International Nuclear Information System (INIS)

    Poland, R.E.; Rubin, R.T.

    1981-01-01

    A radioimmunoassay (RIA) for measurement of serum haloperidol is described. Compared to gaschromatography (GC), RIA vaues average 40% higher. However, a simple organic extraction of serum yields statistically equivalent RIA and GC haloperidol determinations. For both men and women combined, there was a positive correlation between dose (mg/kg/day) and steady-state serum haloperidol level (r = +0.86) and between steady-state serum haloperidol and serum prolactin (PRL) concentration

  11. Origin of DNA in human serum and usefulness of serum as a material for DNA typing.

    Science.gov (United States)

    Takayama, T; Yamada, S; Watanabe, Y; Hirata, K; Nagai, A; Nakamura, I; Bunai, Y; Ohya, I

    2001-06-01

    The aims of this study were to clarify the origin of DNA in human serum and to investigate whether serum is a material available for DNA typing in routine forensic practice. Blood was donated from 10 healthy adult volunteers and stored for up to 8 days, at 4 degrees C and at room temperature. The serum DNA concentration at zero time was in the range of 5.6 to 21.8 ng/ml with a mean of 12.2+/-1.6 ng/ml. The concentrations increased with storage time. On agarose gel electrophoresis, all serum samples showed ladder patterns and the size of each band was an integer multiple of approximately 180 bp considered to be characteristic of apoptosis. DNA typing from DNA released by apoptosis was possible. Exact DNA typing of D1S80, HLA DQA1, PM, CSF1PO, TPOX, TH01 and vWA was possible for each sample. These results indicate that serum contains fragmented DNA derived from apoptosis of leukocytes, especially neutrophils, and that fragmented DNA is an appropriate material for DNA typing.

  12. Clinical chemistry measurements with commercially available test slides on a smartphone platform: Colorimetric determination of glucose and urea.

    Science.gov (United States)

    Wu, Yuanyuan; Boonloed, Anukul; Sleszynski, Neal; Koesdjojo, Myra; Armstrong, Chadd; Bracha, Shay; Remcho, Vincent T

    2015-08-25

    Rapidly increasing healthcare costs in economically advantaged countries are currently unsustainable, while in many developing nations, even 50-year-old technologies are too expensive to implement. New and unconventional technologies are being explored as solutions to this problem. In this study, we examined the use of a smartphone as the detection platform for 2 well-developed, relatively inexpensive, commercially available clinical chemistry assays as a model for rapid and inexpensive clinical diagnostic testing. An Apple iPhone 4 camera phone equipped with a color analysis application (ColorAssist) was combined with Vitros® glucose and urea colorimetric assays. Color images of assay slides at various concentrations of glucose or urea were collected with the iPhone 4 and quantitated in three different spectral ranges (red/green/blue or RGB) using the ColorAssist app. When the diffuse reflectance data was converted into absorbance, it was possible to quantitate glucose or blood urea nitrogen (BUN) over their clinically important concentration ranges (30-515mg/dl for glucose or 2-190mg/dl for BUN), with good linearity (R(2)=0.9994 or 0.9996, respectively [n=5]). Data collected using the iPhone 4 and canine serum samples were in agreement with results from the instrumental "gold standard" (Beckman Coulter AU480 Chemistry System) (R(2)=0.9966 and slope=1.0001 for glucose; R(2)=0.9958 and slope=0.9454 for BUN). Glucose determinations of serum samples made using this smartphone method were as accurate as or more accurate than a commercial colorimetric dry slide analyzer (Heska® Element DC Chemistry Analyzer, Loveland, CO) and 2 glucometers: ReliOn® Ultima (Abbott Diabetes Care Inc) and Presto® (AgaMatrix Inc.H). BUN determinations made using the smartphone approach were comparable in accuracy to the Heska instrument. This demonstration shows that smartphones have the potential to be used as simple, effective colorimetric detectors for quantitative diagnostic tests

  13. Extending the half-life of a fab fragment through generation of a humanized anti-human serum albumin Fv domain: An investigation into the correlation between affinity and serum half-life.

    Science.gov (United States)

    Adams, Ralph; Griffin, Laura; Compson, Joanne E; Jairaj, Mark; Baker, Terry; Ceska, Tom; West, Shauna; Zaccheo, Oliver; Davé, Emma; Lawson, Alastair Dg; Humphreys, David P; Heywood, Sam

    2016-10-01

    We generated an anti-albumin antibody, CA645, to link its Fv domain to an antigen-binding fragment (Fab), thereby extending the serum half-life of the Fab. CA645 was demonstrated to bind human, cynomolgus, and mouse serum albumin with similar affinity (1-7 nM), and to bind human serum albumin (HSA) when it is in complex with common known ligands. Importantly for half-life extension, CA645 binds HSA with similar affinity within the physiologically relevant range of pH 5.0 - pH 7.4, and does not have a deleterious effect on the binding of HSA to neonatal Fc receptor (FcRn). A crystal structure of humanized CA645 Fab in complex with HSA was solved and showed that CA645 Fab binds to domain II of HSA. Superimposition with the crystal structure of FcRn bound to HSA confirmed that CA645 does not block HSA binding to FcRn. In mice, the serum half-life of humanized CA645 Fab is 84.2 h. This is a significant extension in comparison with Fab variant. The Fab-HSA structure was used to design a series of mutants with reduced affinity to investigate the correlation between the affinity for albumin and serum half-life. Reduction in the affinity for MSA by 144-fold from 2.2 nM to 316 nM had no effect on serum half-life. Strikingly, despite a reduction in affinity to 62 µM, an extension in serum half-life of 26.4 h was still obtained. CA645 Fab and the CA645 Fab-HSA complex have been deposited in the Protein Data Bank (PDB) with accession codes, 5FUZ and 5FUO, respectively.

  14. Multiplexed activity-based protein profiling of the human pathogen Aspergillus fumigatus reveals large functional changes upon exposure to human serum.

    Science.gov (United States)

    Wiedner, Susan D; Burnum, Kristin E; Pederson, LeeAnna M; Anderson, Lindsey N; Fortuin, Suereta; Chauvigné-Hines, Lacie M; Shukla, Anil K; Ansong, Charles; Panisko, Ellen A; Smith, Richard D; Wright, Aaron T

    2012-09-28

    Environmental adaptability is critical for survival of the fungal human pathogen Aspergillus fumigatus in the immunocompromised host lung. We hypothesized that exposure of the fungal pathogen to human serum would lead to significant alterations to the organism's physiology, including metabolic activity and stress response. Shifts in functional pathway and corresponding enzyme reactivity of A. fumigatus upon exposure to the human host may represent much needed prognostic indicators of fungal infection. To address this, we employed a multiplexed activity-based protein profiling (ABPP) approach coupled to quantitative mass spectrometry-based proteomics to measure broad enzyme reactivity of the fungus cultured with and without human serum. ABPP showed a shift from aerobic respiration to ethanol fermentation and utilization over time in the presence of human serum, which was not observed in serum-free culture. Our approach provides direct insight into this pathogen's ability to survive, adapt, and proliferate. Additionally, our multiplexed ABPP approach captured a broad swath of enzyme reactivity and functional pathways and provides a method for rapid assessment of the A. fumigatus response to external stimuli.

  15. Multiplexed Activity-based Protein Profiling of the Human Pathogen Aspergillus fumigatus Reveals Large Functional Changes upon Exposure to Human Serum*

    Science.gov (United States)

    Wiedner, Susan D.; Burnum, Kristin E.; Pederson, LeeAnna M.; Anderson, Lindsey N.; Fortuin, Suereta; Chauvigné-Hines, Lacie M.; Shukla, Anil K.; Ansong, Charles; Panisko, Ellen A.; Smith, Richard D.; Wright, Aaron T.

    2012-01-01

    Environmental adaptability is critical for survival of the fungal human pathogen Aspergillus fumigatus in the immunocompromised host lung. We hypothesized that exposure of the fungal pathogen to human serum would lead to significant alterations to the organism's physiology, including metabolic activity and stress response. Shifts in functional pathway and corresponding enzyme reactivity of A. fumigatus upon exposure to the human host may represent much needed prognostic indicators of fungal infection. To address this, we employed a multiplexed activity-based protein profiling (ABPP) approach coupled to quantitative mass spectrometry-based proteomics to measure broad enzyme reactivity of the fungus cultured with and without human serum. ABPP showed a shift from aerobic respiration to ethanol fermentation and utilization over time in the presence of human serum, which was not observed in serum-free culture. Our approach provides direct insight into this pathogen's ability to survive, adapt, and proliferate. Additionally, our multiplexed ABPP approach captured a broad swath of enzyme reactivity and functional pathways and provides a method for rapid assessment of the A. fumigatus response to external stimuli. PMID:22865858

  16. Plasmonic colorimetric sensors based on etching and growth of noble metal nanoparticles: Strategies and applications.

    Science.gov (United States)

    Zhang, Zhiyang; Wang, Han; Chen, Zhaopeng; Wang, Xiaoyan; Choo, Jaebum; Chen, Lingxin

    2018-08-30

    Plasmonic colorimetric sensors have emerged as a powerful tool in chemical and biological sensing applications due to the localized surface plasmon resonance (LSPR) extinction in the visible range. Among the plasmonic sensors, the most famous sensing mode is the "aggregation" plasmonic colorimetric sensor which is based on plasmon coupling due to nanoparticle aggregation. Herein, this review focuses on the newly-developing plasmonic colorimetric sensing mode - the etching or the growth of metal nanoparticles induces plasmon changes, namely, "non-aggregation" plasmonic colorimetric sensor. This type of sensors has attracted increasing interest because of their exciting properties of high sensitivity, multi-color changes, and applicability to make a test strip. Of particular interest, the test strip by immobilization of nanoparticles on the substrate can avoid the influence of nanoparticle auto-aggregation and increase the simplicity in storage and use. Although there are many excellent reviews available that describe the advance of plasmonic sensors, limited attention has been paid to the plasmonic colorimetric sensors based on etching or growth of metal nanoparticles. This review highlights recent progress on strategies and application of "non-aggregation" plasmonic colorimetric sensors. We also provide some personal insights into current challenges associated with "non-aggregation" plasmonic colorimetric sensors and propose future research directions. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Mass fragmentographic analysis of total cholesterol in serum using a heptadeuterated internal standard

    International Nuclear Information System (INIS)

    Wolthers, B.G.; Hindriks, F.R.; Muskiet, F.A.J.; Groen, A.

    1980-01-01

    A mass fragmentographic method for the determination of total cholesterol in serum using heptadeuterated [25,26,26,26,27,27,27- 2 H] cholesterol as internal standard is presented. The results obtained are compared with a colorimetric and gas chromatographic method which were previously proposed as reference methods. Criteria for the development of absolute measurement by means of mass fragmentography and stable isotopically labelled internal standards are given. The conclusion is drawn that, at present, mass fragmentographic methods for the determination of total cholesterol in serum do not fulfil the criteria required for absolute methods. (Auth.)

  18. Polymerized soluble venom--human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, R.; Suszko, I.M.; Grammer, L.C.

    1985-03-01

    Extensive previous studies have demonstrated that attempts to produce polymers of Hymenoptera venoms for human immunotherapy resulted in insoluble precipitates that could be injected with safety but with very limited immunogenicity in allergic patients. We now report soluble polymers prepared by conjugating bee venom with human serum albumin with glutaraldehyde. The bee venom-albumin polymer (BVAP) preparation was fractionated on Sephacryl S-300 to have a molecular weight range higher than catalase. /sup 125/I-labeled bee venom phospholipase A was almost completely incorporated into BVAP. Rabbit antibody responses to bee venom and bee venom phospholipase A were induced by BVAP. Human antisera against bee venom were absorbed by BVAP. No new antigenic determinants on BVAP were present as evidenced by absorption of antisera against BVAP by bee venom and albumin. BVAP has potential immunotherapeutic value in patients with anaphylactic sensitivity to bee venom.

  19. The effect of essential hypertension on serum uric acid level

    International Nuclear Information System (INIS)

    Jawed, S.; Khawaja, T.F.; Sultan, M.A.; Ahmad, S.

    2005-01-01

    Patient with arterial hypertension and no definable cause are said to have essential, primary or idiopathic hypertension. A total of 100 patients suffering from essential hypertension and 100 control subjects with almost same mean age and sex distribution were enrolled in this study. Levels of serum uric acid, total cholesterol, TG, and HDL-c were determined by enzymatic colorimetric method. Serum LDL-c and VLDL-c was calculated by using Friedewald and Wilson's formulae. The study was aimed to find out the levels of serum uric acid and lipid profile in patients with essential hypertension and to compare them with levels of normal healthy individuals. Results show increased level of serum uric acid and lipid parameters except for HDL-c, which was significantly, decreased in patients with essential hypertension as compared to the control subjects. Variations in aforementioned parameters were also observed on comparing the obese and the non-obese patients. It can be concluded from the present study that the essential hypertension is associated with abnormalities in the levels of serum uric acid and lipid profile. (author)

  20. Comparison between human cord blood serum and platelet-rich plasma supplementation for Human Wharton's Jelly Stem Cells and dermal fibroblasts culture

    Directory of Open Access Journals (Sweden)

    Hashemi SS

    2016-08-01

    Full Text Available We carried out a side-by-side comparison of the effects of Human cord blood serum (HcbS versus embryonic PRP on Human Wharton's Jelly Stem Cells(hWMSCand dermal fibroblasts proliferation. Human umbilical cord blood was collected to prepare activated serum (HCS and platelet-rich plasma (CPRP.Wharton's Jelly Stem Cells and dermal fibroblasts were cultured in complete medium with10% CPRP, 10%HCSor 10% fetal bovine serumand control (serum-free media.The efficiency of the protocols was evaluated in terms of the number of adherent cells and their expansion and Cell proliferation. We showed that proliferation of fibroblasts and mesenchymal stem cells in the presence of cord blood serum and platelet-rich plasma significantly more than the control group (p≤0/05. As an alternative to FBS, cord blood serum has been proved as an effective component in cell tissue culture applications and embraced a vast future in clinical applications of regenerative medicine. However, there is still a need to explore the potential of HCS and its safe applications in humanized cell therapy or tissue engineering.

  1. Study the interaction between CdTe-glutathione and human serum albumin

    International Nuclear Information System (INIS)

    Yang, Qing; Zhou, Xi-min; Zhu, Yi-shuo; Chen, Xing-guo

    2013-01-01

    In this paper, glutathione (GSH) modified CdTe quantum dots (CdTe-GSH QDs) were synthesized in an aqueous solution. Then, the binding of the CdTe-GSH QDs to human serum albumin (HSA) was studied using the fluorescence spectroscopy. The quenching mechanism was investigated in terms of the association constants and basic thermodynamic parameters. The fluorescence data revealed that CdTe-GSH QDs could quench the intrinsic fluorescence of human serum albumin by a static quenching mechanism. Furthermore, alteration of the secondary protein structure in the presence of the QDs was confirmed by synchronous fluorescence spectra. - Highlights: ► In this paper, the binding of the CdTe-GSH QDs to human serum albumin (HSA) was studied using a fluorescence spectroscopy. ► The quenching mechanism was investigated in terms of the association constants and basic thermodynamic parameters. ► Furthermore, alteration of the secondary protein structure in the presence of the QDs was confirmed by synchronous fluorescence spectra. ► The research can help us assess biological toxicity of QDs and further expand the application scope of QDs.

  2. Gamma radiation effects on liofilized human serum

    International Nuclear Information System (INIS)

    Padron Soler, E.; Romay Penabad, Z.; Chavez Ardanza, A.; Hernandez Gonzalez, C.; Martin Gonzalez, O.; Garcia Gonzalez, I.; Prieto Miranda, E.

    1995-01-01

    Human freeze dried serum was artificially contaminated with Flavobacterium sp. for studying the effects of gamma radiation of it. The radiobiological parameters of the contaminator were determined and the sterilization dose was set. The quality of the product irradiated at both, calculated sterilization dose (8.5 kGy) an another one about 25 kGy was determined. It was made according to: sterility testing, total proteins, pH enzymes (alanina-aminotransferase, aspartato-aminotransferase, alkaline phosphatase), protein electrophoresis, fast performance liquid chromatographic and effect on the cellular growth. From the latter was concluded that the calculated sterilization dose was adequate form keeping the biological properties and viability of the irradiated serum. Nevertheless, the dose of 25 k Gy was not adequate because of its dangerous effects on the cell culture

  3. A low percentage of autologous serum can replace bovine serum to engineer human nasal cartilage

    Directory of Open Access Journals (Sweden)

    F Wolf

    2008-02-01

    Full Text Available For the generation of cell-based therapeutic products, it would be preferable to avoid the use of animal-derived components. Our study thus aimed at investigating the possibility to replace foetal bovine serum (FBS with autologous serum (AS for the engineering of cartilage grafts using expanded human nasal chondrocytes (HNC. HNC isolated from 7 donors were expanded in medium containing 10% FBS or AS at different concentrations (2%, 5% and 10% and cultured in pellets using serum-free medium or in Hyaff®-11 meshes using medium containing FBS or AS. Tissue forming capacity was assessed histologically (Safranin O, immunohistochemically (type II collagen and biochemically (glycosaminoglycans -GAG- and DNA. Differences among experimental groups were assessed by Mann Whitney tests. HNC expanded under the different serum conditions proliferated at comparable rates and generated cartilaginous pellets with similar histological appearance and amounts of GAG. Tissues generated by HNC from different donors cultured in Hyaff®-11 had variable quality, but the accumulated GAG amounts were comparable among the different serum conditions. Staining intensity for collagen type II was consistent with GAG deposition. Among the different serum conditions tested, the use of 2% AS resulted in the lowest variability in the GAG contents of generated tissues. In conclusion, a low percentage of AS can replace FBS both during the expansion and differentiation of HNC and reduce the variability in the quality of the resulting engineered cartilage tissues.

  4. Elevated Serum Level of Human Alkaline Phosphatase in Obesity

    International Nuclear Information System (INIS)

    Khan, A. R.; Awan, F. R.; Najam, S. S.; Islam, M.; Siddique, T.; Zain, M.

    2015-01-01

    Objective: To investigate a correlation between serum alkaline phosphatase level and body mass index in human subjects. Methods: The comparative cross-sectional study was carried out at the National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan, from April 2012 to June 2013. Blood serum alkaline phosphatase levels were estimated and the subjects were divided into three sub-groups on the basis of their body mass index: normal weight (<25kg/m2), overweight (25-27kg/m2) and obese (>27kg/m2) subjects. The serum samples were used for the estimation of clinically important biochemical parameters, using commercial kits on clinical chemistry analyser. Results: Of the 197 subjects, 97(49 percent) were obese and 100(51 percent) were non-obese. The serum alkaline phosphatase level increased in obese (214±6.4 IU/L) compared to the non-obese subjects (184.5±5 IU/L). Furthermore, a significant linear relationship (r=0.3;p-0.0001) was found between serum alkaline phosphatase and body mass index. Other biochemical variables were not correlated to the body mass index. Conclusion: Over activity and higher amounts of alkaline phosphatase were linked to the development of obesity. (author)

  5. Aggregation-based colorimetric sensor for determination of prothioconazole fungicide using colloidal silver nanoparticles (AgNPs)

    Science.gov (United States)

    Ivrigh, Zahra Jafar-Nezhad; Fahimi-Kashani, Nafiseh; Hormozi-Nezhad, M. Reza

    2017-12-01

    There is a growing interest in developing high-performance sensors monitoring fungicides, due to their broadly usage and their adverse effects on humans and wildlife. In the present study, a colorimetric probe has been proposed for detection of prothioconazole based on aggregation of unmodified silver nanoparticles (AgNPs). Under optimized condition, linear relationships between the concentration of prothioconazole and the absorbance ratio of A500/A395 were found over the range of 0.01 μg·mL- 1 to 0.4 μg·mL- 1 with quantification limit as low as 1.7 ng·mL- 1. Furthermore, AgNPs color change from yellow to pink-orange in presence of prothioconazole, indicates highly sensitive naked-eye colorimetric assay for quantifying prothioconazole in real applications. The proposed approach was successfully used for the determination of prothioconazole in wheat flour and paddy water sample.

  6. Human serum albumin mediated self-assembly of gold nanoparticles into hollow spheres

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, Nimai C [Singapore-MIT Alliance, Manufacturing Systems and Technology Programme, Nanyang Technological University, 65 Nanyang Drive, 637460 (Singapore); Shin, Kwanwoo [Interdisciplinary Program of Integrated Biotechnology, Sogang University, Shinsoo-dong, Mapo-gu, Seoul 121-742 (Korea, Republic of)], E-mail: ncnayak@gmail.com

    2008-07-02

    The assembly of nanoparticles in topologically predefined superstructures is an important area in nanoscale architecture. In this paper, we report an unusual aggregation phenomenon involving L-lysine capped gold nanoparticles and human serum albumin into hollow nanospheres. The electrostatic interaction between positively charged L-lysine capped gold nanoparticles and negatively charged human serum albumin at physiological pH led to the assembly of the gold nanoparticles into hollow spheres. The phenomenon can be explained by the dry hole opening mechanism.

  7. Human serum albumin mediated self-assembly of gold nanoparticles into hollow spheres

    International Nuclear Information System (INIS)

    Nayak, Nimai C; Shin, Kwanwoo

    2008-01-01

    The assembly of nanoparticles in topologically predefined superstructures is an important area in nanoscale architecture. In this paper, we report an unusual aggregation phenomenon involving L-lysine capped gold nanoparticles and human serum albumin into hollow nanospheres. The electrostatic interaction between positively charged L-lysine capped gold nanoparticles and negatively charged human serum albumin at physiological pH led to the assembly of the gold nanoparticles into hollow spheres. The phenomenon can be explained by the dry hole opening mechanism

  8. The development of retrosynthetic glycan libraries to profile and classify the human serum N-linked glycome.

    Science.gov (United States)

    Kronewitter, Scott R; An, Hyun Joo; de Leoz, Maria Lorna; Lebrilla, Carlito B; Miyamoto, Suzanne; Leiserowitz, Gary S

    2009-06-01

    Annotation of the human serum N-linked glycome is a formidable challenge but is necessary for disease marker discovery. A new theoretical glycan library was constructed and proposed to provide all possible glycan compositions in serum. It was developed based on established glycobiology and retrosynthetic state-transition networks. We find that at least 331 compositions are possible in the serum N-linked glycome. By pairing the theoretical glycan mass library with a high mass accuracy and high-resolution MS, human serum glycans were effectively profiled. Correct isotopic envelope deconvolution to monoisotopic masses and the high mass accuracy instruments drastically reduced the amount of false composition assignments. The high throughput capacity enabled by this library permitted the rapid glycan profiling of large control populations. With the use of the library, a human serum glycan mass profile was developed from 46 healthy individuals. This paper presents a theoretical N-linked glycan mass library that was used for accurate high-throughput human serum glycan profiling. Rapid methods for evaluating a patient's glycome are instrumental for studying glycan-based markers.

  9. Serum lutein concentrations in healthy term infants fed human milk or infant formula with lutein.

    Science.gov (United States)

    Bettler, Jodi; Zimmer, J Paul; Neuringer, Martha; DeRusso, Patricia A

    2010-02-01

    Lutein is a carotenoid that may play a role in eye health. Human milk typically contains higher concentrations of lutein than infant formula. Preliminary data suggest there are differences in serum lutein concentrations between breastfed and formula-fed infants. To measure the serum lutein concentrations among infants fed human milk or formulas with and without added lutein. A prospective, double-masked trial was conducted in healthy term formula-fed infants (n = 26) randomized between 9 and 16 days of age to study formulas containing 20 (unfortified), 45, 120, and 225 mcg/l of lutein. A breastfed reference group was studied (n = 14) and milk samples were collected from their mothers. Primary outcome was serum lutein concentration at week 12. Geometric mean lutein concentration of human milk was 21.1 mcg/l (95% CI 14.9-30.0). At week 12, the human milk group had a sixfold higher geometric mean serum lutein (69.3 mcg/l; 95% CI 40.3-119) than the unfortified formula group (11.3 mcg/l; 95% CI 8.1-15.8). Mean serum lutein increased from baseline in each formula group except the unfortified group. Linear regression equation indicated breastfed infants had a greater increase in serum lutein (slope 3.7; P milk lutein than formula-fed infants (slope 0.9; P lutein concentrations than infants who consume formula unfortified with lutein. These data suggest approximately 4 times more lutein is needed in infant formula than in human milk to achieve similar serum lutein concentrations among breastfed and formula fed infants.

  10. Paper-based tuberculosis diagnostic devices with colorimetric gold nanoparticles

    International Nuclear Information System (INIS)

    Tsai, Tsung-Ting; Shen, Shu-Wei; Chen, Chien-Fu; Cheng, Chao-Min

    2013-01-01

    A colorimetric sensing strategy employing gold nanoparticles and a paper assay platform has been developed for tuberculosis diagnosis. Unmodified gold nanoparticles and single-stranded detection oligonucleotides are used to achieve rapid diagnosis without complicated and time-consuming thiolated or other surface-modified probe preparation processes. To eliminate the use of sophisticated equipment for data analysis, the color variance for multiple detection results was simultaneously collected and concentrated on cellulose paper with the data readout transmitted for cloud computing via a smartphone. The results show that the 2.6 nM tuberculosis mycobacterium target sequences extracted from patients can easily be detected, and the turnaround time after the human DNA is extracted from clinical samples was approximately 1 h. (paper)

  11. Feature extraction using distribution representation for colorimetric sensor arrays used as explosives detectors

    DEFF Research Database (Denmark)

    Alstrøm, Tommy Sonne; Raich, Raviv; Kostesha, Natalie

    2012-01-01

    is required. We present a new approach of extracting features from a colorimetric sensor array based on a color distribution representation. For each sensor in the array, we construct a K-nearest neighbor classifier based on the Hellinger distances between color distribution of a test compound and the color......We present a colorimetric sensor array which is able to detect explosives such as DNT, TNT, HMX, RDX and TATP and identifying volatile organic compounds in the presence of water vapor in air. To analyze colorimetric sensors with statistical methods, a suitable representation of sensory readings...

  12. Degalactosylated/desialylated human serum containing GcMAF induces macrophage phagocytic activity and in vivo antitumor activity.

    Science.gov (United States)

    Kuchiike, Daisuke; Uto, Yoshihiro; Mukai, Hirotaka; Ishiyama, Noriko; Abe, Chiaki; Tanaka, Daichi; Kawai, Tomohito; Kubo, Kentaro; Mette, Martin; Inui, Toshio; Endo, Yoshio; Hori, Hitoshi

    2013-07-01

    The group-specific component protein-derived macrophage-activating factor (GcMAF) has various biological activities, such as macrophage activation and antitumor activity. Clinical trials of GcMAF have been carried out for metastatic breast cancer, prostate cancer, and metastatic colorectal cancer. In this study, despite the complicated purification process of GcMAF, we used enzymatically-treated human serum containing GcMAF with a considerable macrophage-stimulating activity and antitumor activity. We detected GcMAF in degalactosylated/desialylated human serum by western blotting using an anti-human Gc globulin antibody, and Helix pomatia agglutinin lectin. We also found that GcMAF-containing human serum significantly enhanced the phagocytic activity of mouse peritoneal macrophages and extended the survival time of mice bearing Ehrlich ascites tumors. We demonstrated that GcMAF-containing human serum can be used as a potential macrophage activator for cancer immunotherapy.

  13. (99m) Tc-labelled human serum albumin cannot replace (125) I-labelled human serum albumin to determine plasma volume in patients with liver disease

    DEFF Research Database (Denmark)

    Henriksen, Ulrik Lütken; Henriksen, Jens H; Bendtsen, Flemming

    2013-01-01

    Summary Background and aims Determination of plasma volume (PV) is important in several clinical situations. Thus, patients with liver disease often have augmented PV as part of their sodium–water retention. This study was undertaken to compare PV determination by two indicators: technetium......-labelled human serum albumin (99mTc-HSA) and iodine-labelled human serum albumin (125I-HSA), as the former may have advantages at repeated measurements and the latter is the classical gold standard. Study population and methods In 88 patients, (64 with liver disease, mainly cirrhosis, and 24 patients without...... In all patients, a close correlation was present between PV determined by the two indicators (r = 0·89, Pdetermined with 99mTc-HSA exceeded PV determined with 125I-HSA by 367 ml (5·2 ml kg...

  14. Raman spectroscopy in investigations of mechanism of binding of human serum albumin to molecular probe fluorescein

    International Nuclear Information System (INIS)

    Vlasova, I M; Saletsky, A M

    2008-01-01

    The mechanism of binding of molecular probe fluorescein to molecules of human serum albumin was studied by the Raman spectroscopy method. The position of binding Center on human serum albumin molecule for fluorescein is determined. The amino acid residues of albumin molecule, participating in binding of fluorescein at different pH values of solution, are established. The conformation rearrangements of globules of human serum albumin, taking place at binding of fluorescein at different pH values of solution, are registered

  15. Highly efficient human serum filtration with water-soluble nanoporous nanoparticles

    Directory of Open Access Journals (Sweden)

    Antonella Pujia

    2010-11-01

    Full Text Available Antonella Pujia1, Francesco De Angelis1,2, Domenica Scumaci3, Marco Gaspari3, Carlo Liberale1,2, Patrizio Candeloro1, Giovanni Cuda3, Enzo Di Fabrizio1,21BIONEM Laboratory, Department of Experimental and Clinical Medicine, University of Catanzaro “Magna Graecia”, Germaneto (CZ, Italy; 2IIT, Italian Institute of Technology, Genova, Italy; 3Proteomics and Mass Spectrometry Laboratory, Department of Experimental and Clinical Medicine, University of Catanzaro “Magna Graecia”, Germaneto (CZ, ItalyBackground: Human serum has the potential to become the most informative source of novel biomarkers, but its study is very difficult due to the incredible complexity of its molecular composition. We describe a novel tool based on biodegradable nanoporous nanoparticles (NPNPs that allows the harvesting of low-molecular-weight fractions of crude human serum or other biofluids. NPNPs with a diameter of 200 nm and pore size of a few nm were obtained by ultrasonication of nanoporous silicon. When incubated with a solution, the NPNPs harvest only the molecules small enough to be absorbed into the nanopores. Then they can be recovered by centrifugation and dissolved in water, making the harvested molecules available for further analyses.Results: Fluorescence microscopy, gel electrophoresis, and mass spectrometry were used to show the enrichment of low-molecular-weight fraction of serum under physiological conditions, with a cut-off of 13 kDa and an enrichment factor >50.Conclusion: From these findings, we conclude that ability to tune pore size, combined with the availability of hundreds of biomolecule cross-linkers, opens up new perspectives on complex biofluid analysis, discovery of biomarkers, and in situ drug delivery.Keywords: nanoporous silicon, nanoparticle, biomarker discovery, human serum proteomics, harvesting

  16. Comparison of tetrazolium colorimetric and [3H]-uridine assays for in vitro chemosensitivity testing.

    Science.gov (United States)

    Ford, C H; Richardson, V J; Tsaltas, G

    1989-01-01

    We have routinely used a [3H]-uridine microplate assay for assessing chemosensitivity. A colorimetric assay with the advantages of safety, cost and simplicity has previously been described and relies on the ability of living cells to reduce a soluble tetrazolium salt, 3-4,5-dimethylthiazol-2,5-diphenyl-tetrazolium bromide (MMT), into an insoluble formazan precipitate. We compared the chemosensitivity of 14 human tumour cell lines of colonic, lung and cervical carcinoma origin to doxorubicin, vindesine or vindesine immunoconjugates in both the [3H]-uridine assay and a modified MTT assay to evaluate whether we could change to the non-radiolabelled method. Correlation between the concentration of drug causing 50% inhibition of cell growth (IC50) for these agents between the two assays was very poor. However, taking account of recent reports in the literature, we modified the MTT assay by removing serum-containing medium and using dimethyl sulphoxide to solubilise the formazan precipitate. This considerably improved the correlation between the assays for doxorubicin (r = 0.871; P = 0.001) and vindesine (r = 0.981; P less than 0.001). Our data indicates that the MTT assay can be used to replace the [3H]-uridine assay for chemosensitivity screening, but further modifications are necessary to improve the sensitivity and decrease the problem of cell loss after washing, which was noted with some adherent cell lines.

  17. Study the interaction between CdTe-glutathione and human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qing; Zhou, Xi-min; Zhu, Yi-shuo [National Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China); Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Chen, Xing-guo, E-mail: chenxg@lzu.edu.cn [National Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China); Department of Chemistry, Lanzhou University, Lanzhou 730000 (China)

    2013-03-15

    In this paper, glutathione (GSH) modified CdTe quantum dots (CdTe-GSH QDs) were synthesized in an aqueous solution. Then, the binding of the CdTe-GSH QDs to human serum albumin (HSA) was studied using the fluorescence spectroscopy. The quenching mechanism was investigated in terms of the association constants and basic thermodynamic parameters. The fluorescence data revealed that CdTe-GSH QDs could quench the intrinsic fluorescence of human serum albumin by a static quenching mechanism. Furthermore, alteration of the secondary protein structure in the presence of the QDs was confirmed by synchronous fluorescence spectra. - Highlights: Black-Right-Pointing-Pointer In this paper, the binding of the CdTe-GSH QDs to human serum albumin (HSA) was studied using a fluorescence spectroscopy. Black-Right-Pointing-Pointer The quenching mechanism was investigated in terms of the association constants and basic thermodynamic parameters. Black-Right-Pointing-Pointer Furthermore, alteration of the secondary protein structure in the presence of the QDs was confirmed by synchronous fluorescence spectra. Black-Right-Pointing-Pointer The research can help us assess biological toxicity of QDs and further expand the application scope of QDs.

  18. A sensitive colorimetric aptasensor based on trivalent peroxidase-mimic DNAzyme and magnetic nanoparticles.

    Science.gov (United States)

    Liu, Shuwen; Xu, Naihan; Tan, Chunyan; Fang, Wei; Tan, Ying; Jiang, Yuyang

    2018-08-14

    In this study, a novel colorimetric aptasensor was prepared by coupling trivalent peroxidase-mimic DNAzyme and magnetic nanoparticles for highly sensitive and selective detection of target proteins. A three G-quadruplex (G4) DNA-hemin complex was employed as the trivalent peroxidase-mimic DNAzyme, in which hemin assisted the G4-DNA to fold into a catalytic conformation and act as an enzyme. The design of the aptasensor includes magnetic nanoparticles (MNPs), complementary DNA (cDNA) modified with biotin, and a label-free single strand DNA (ssDNA) including the aptamer and trivalent peroxidase-mimic DNAzyme. The trivalent DNAzyme, which has the highest catalytic activity among multivalent DNAzymes, catalyzed the H 2 O 2 -mediated oxidation of ABTS. The colorless ABTS was oxidized to produce a blue-green product that can be clearly distinguished by the naked eye. The aptamer and trivalent peroxidase-mimic DNAzyme promote the specificity and sensitivity of this detection method, which can be generalized for other targets by simply replacing the corresponding aptamers. To demonstrate the feasible use of the aptasensor for target detection, a well-known tumor biomarker MUC1 was evaluated as the model target. The limits of detection were determined to be 5.08 and 5.60 nM in a linear range of 50-1000 nM in a buffer solution and 10% serum system, respectively. This colorimetric and label-free aptasensor with excellent sensitivity and strong anti-interference ability has potential application in disease diagnoses, prognosis tracking, and therapeutic evaluation. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. The measurement of serum human parathyroid hormone (h-PTH53-84) and effect of exercise on calcium metabolism

    International Nuclear Information System (INIS)

    Torizumi, Kazutami; Taniguchi, Yoshiyuki; Aibata, Hirofumi; Kiji, Shigeyuki; Ueyoshi, Akitaka; Shimizu, Eiji; Okamoto, Yukiharu; Tuda, Tadaaki; Ota, Kiichiro

    1987-01-01

    This study was focussed our attention on the measurement within the upper physiological level of human serum parathyroid hormone (PTH), using kits of human PTH 53 - 84. This assay kit was able to detect serum PTH in sera with suble changes of serum calcium concentrations before and after short term exercise. These serum PTH levels before and after exercise seemed to be changed within the upper physiological levels of PTH. Thus, this study suggested that the assay kit was likely to become a useful tool of the measurement of the physiological level of serum PTH in humans. (author)

  20. Determination of mercury in human serum and packed blood cells by neutron activation analysis

    International Nuclear Information System (INIS)

    Versieck, J.; Vanballenberghe, L.; Wittoek, A.; Vermeir, G.; Vandecasteele, C.

    1990-01-01

    A method is described for the determination of mercury in human blood serum and packed blood cells employing neutron activation analysis. Great attention was devoted to the collection and manipulation of the samples. The accuracy and precision of the method were tested by analyzing biological reference materials and by comparing the concentrations measured in a number of serum samples to those obtained by another, independent technique (cold vapor atomic absorption spectrometry) in the same samples. The article reports the levels measured in blood serum and packed blood cells samples from 15 adult volunteers, as well as the figures determined in a open-quotes second-generationclose quotes biological reference material (freeze-dried human serum), prepared and conditioned at the University of Ghent

  1. The physico-chemical, antigenic, and functional heterogeneity of human serum amyloid A

    International Nuclear Information System (INIS)

    Martin, M.E.; HUq, A.; Rosenthal, C.J.

    1986-01-01

    In the present study we attempted to develop a rapid method to isolate serum amyloid A isomers (SAA is.) and to determine whether this physicochemical heterogeneity corresponds to an antigenic and functional one. Pure human low molecular SAA (SAAL) was prepared from the serum of 6 patients (pts.) using standard techniques. Preparative isoelectric focusing in agarose/sephadex gels was used to separate SAAL is. Monoclonal antibodies (m. abs.) to SAAL and to AA were prepared by hybridization of P3XU-1 nonsecretory murine myeloma cells with murine spleen cells from Balb/c mice immunized with pooled SAAL and AA respectively. Four distinctly migrating SAAL isomers with PI's of 4.9, 5.8, 6.6, and 7.2 were isolated from 6 pts. while only three isomers were separated from the pt. with myasthenia gravis. Four m. abs. to SAAL, one to AA, six m. abs. to SAAL-2 is. and one to SAAL-1 is. were generated in murine ascitic fluid. Dishes coated with the four human SAA is., human AA, various mammalian and human proteins as well as with serum from 31 pts. with metastatic Ca. and 23 pts. with inflammatory diseases (ID) were reacted with the m. abs. The amount of binding was determined using 125 I labelled goat antimouse serum. The m. abs. to SAA were found specific for human SAA recognizing two different patterns in relationship to the intensity of binding to SAA is. One of them (7A2-43) had a greater affinity for SAA from pts with ID, while the other (5A6-5) reacted stronger with SAA from pts with metastatic Ca

  2. Labelling of human serum albumin with iodine-131 for diagnosis in nuclear medicine

    International Nuclear Information System (INIS)

    Silva Valente Goncalves, R. da.

    1979-01-01

    Labelling of 131 I-human serum albumin with I-131 from a solution of 131 I-sodium iodide using chloramine T as an oxidant agent is studied. Parameters which can influence on the labelling yield like mass of human serum albumin, and chloramine T, pH of the reaction, reaction time and activity of 131 I are also studied. The purification of the labeled product by means of IRA-410 Amberlite ion-exchange resin in chloride form and the sterilization of the 131 I-human serum albumin by its passage through a 0,22μ millipore filter are carried out. The radiochemistry control of the final product by paper chromatography and the microbiological control by cultivation of microorganisms in fluid medium: nutrient broth, sodium thioglycollate broth and Sabouraud, are performed. The stability of the radiopharmaceutical until ten days after its preparation is analysed by means of radiochemical control. (Author) [pt

  3. CCQM-K11.2 determination of glucose in human serum and CCQM-K12.2 determination of creatinine in human serum

    Science.gov (United States)

    Wise, Stephen A.; Phinney, Karen W.; Duewer, David L.; Sniegoski, Lorna T.; Welch, Michael J.; Pritchett, Jeanita; Pabello, Guiomar; Avila Calderon, Marco A.; Balderas, Miryan; Qinde, Liu; Kooi, Lee Tong; Rego, Eliane; Garrido, Bruno; Allegri, Gabriella; de La Cruz, Marcia; Barrabin, Juliana; Monteiro, Tânia; Lee, Hwashim; Kim, Byungjoo; Delatour, Vincent; Peignaux, Maryline; Kawaguchi, Migaku; Bei, Xu; Can, Quan; Nammoonnoy, Jintana; Schild, Katrin; Ohlendorf, Rüdiger; Henrion, Andre; Ceyhan Gören, Ahmet; Yılmaz, Hasibe; Bilsel, Mine; Konopelko, L.; Krylov, A.; Lopushanskaya, E.

    2018-01-01

    Glucose and creatinine are two of the most frequently measured substances in human blood/serum for assessing the health status of individuals. Because of their clinical significance, CCQM-K11 glucose in human serum and CCQM-K12 creatinine in human serum were the fourth and fifth key comparisons (KCs) performed by the Organic Analysis Working Group (OAWG). These KCs were conducted in parallel and were completed in 2001. The initial subsequent KCs for glucose, CCQM-K11.1, and creatinine, CCQM-K12.1, were completed in 2005. Measurements for the next KCs for these two measurands, CCQM-K11.2 and CCQM-K12.2, were completed in 2013. While designed as subsequent KCs, systematic discordances between the participants' and the anchor institution's results in both comparisons lead the OAWG to request reference results from two experienced laboratories that had participated in the 2001 comparisons. Based on the totality of the available information, the OAWG converted both CCQM-K11.2 and CCQM-K12.2 to 'Track C' KCs where the key comparison reference value is estimated by consensus. These comparisons highlighted that carrying out comparisons for complex chemical measurements and expecting to be able to treat them under the approaches used for formal CIPM subsequent comparisons is not an appropriate strategy. The approach used here is a compromise to gain the best value from the comparison; it is not an approach that will be used in the future. Instead, the OAWG will focus on Track A and Track C comparisons that are treated as stand-alone entities. Participation in CCQM-K11.2 demonstrates a laboratory's capabilities to measure a polar (pKow > 2), low molecular mass (100 g/mol to 500 g/mol) metabolite in human serum at relatively high concentrations (0.1 mg/g to 10 mg/g). Participation in CCQM-K12.2 demonstrates capabilities to measure similar classes of metabolites at relatively low concentrations (1 μg/g to 30 μg/g). The capabilities required for the analysis of complex

  4. Human Serum is as Efficient as Fetal Bovine Serum in Supporting Proliferation and Differentiation of Human Multipotent Stromal (Mesenchymal) Stem Cells In Vitro and In Vivo

    DEFF Research Database (Denmark)

    Aldahmash, Abdullah; Haack-Sørensen, Mandana; Al-Nbaheen, May

    2011-01-01

    BACKGROUND: Human multipotent stromal (skeletal, mesenchymal) stem cells (hMSC) are employed in an increasing number of clinical trials for tissue regeneration of age-related degenerative diseases. However, routine use of fetal bovine sera (FBS) for their in vitro expansion is not optimal and may......) or adipocytic markers (PPAR-gamma2, lipoprotein lipase (LPL), aP2), respectively. In order to test for the functional capacity of hMSC-TERT that have been maintained in long-term cultures in the presence of HuS vs. FBS, the cells were mixed with hydroxyapatite/tricalcium phosphate (HA/TCP) and implanted...... subcutaneously in immune deficient mice. hMSC maintained in HuS vs. FBS formed comparable heterotopic bone. DISCUSSION: Human serum can support proliferation and differentiation of hMSC in vitro and can maintain their bone forming capacity in vivo. The use of human serum in cell cultures of hMSC intended...

  5. Detection of human spermatozoal peptides after conjugation to 125I-labelled human serum albumin

    International Nuclear Information System (INIS)

    Metler, L.; Skrabei, H.; Czuppon, A.B.

    1981-01-01

    Human spermatozoal peptides, liberated during autolysis of the cells, were fractionated by gel-filtration chromatography and thin-layer chromatography. After conjugation to 125 I-labelled human serum albumin, all fractions were assayed with rabbit antihuman spermatozoa antiserum. In earlier publications, human sperm-immobilizing and sperm-agglutinating sera were used for the detection of solubilized spermatozoal antigen. The low sensitivity of these tests necessitated a more sensitive test. The purpose of this work is to describe a solid-phase radioimmunoassay for the detection of antigenic peptides

  6. Rapid Colorimetric Detection of Cartap Residues by AgNP Sensor with Magnetic Molecularly Imprinted Microspheres as Recognition Elements

    Directory of Open Access Journals (Sweden)

    Mao Wu

    2018-06-01

    Full Text Available The overuse of cartap in tea tree leads to hazardous residues threatening human health. A colorimetric determination was established to detect cartap residues in tea beverages by silver nanoparticles (AgNP sensor with magnetic molecularly imprinted polymeric microspheres (Fe3O4@mSiO2@MIPs as recognition elements. Using Fe3O4 as supporting core, mesoporous SiO2 as intermediate shell, methylacrylic acid as functional monomer, and cartap as template, Fe3O4@mSiO2@MIPs were prepared to selectively and magnetically separate cartap from tea solution before colorimetric determination by AgNP sensors. The core-shell Fe3O4@mSiO2@MIPs were also characterized by FT-IR, TEM, VSM, and experimental adsorption. The Fe3O4@mSiO2@MIPs could be rapidly separated by an external magnet in 10 s with good reusability (maintained 95.2% through 10 cycles. The adsorption process of cartap on Fe3O4@mSiO2@MIPs conformed to Langmuir adsorption isotherm with maximum adsorption capacity at 0.257 mmol/g and short equilibrium time of 30 min at 298 K. The AgNP colorimetric method semi-quantified cartap ≥5 mg/L by naked eye and quantified cartap 0.1–5 mg/L with LOD 0.01 mg/L by UV-vis spectroscopy. The AgNP colorimetric detection after pretreatment with Fe3O4@mSiO2@MIPs could be successfully utilized to recognize and detect cartap residues in tea beverages.

  7. Improving colorimetric assays through protein enzyme-assisted gold nanoparticle amplification.

    Science.gov (United States)

    Xie, Xiaoji; Xu, Wei; Liu, Xiaogang

    2012-09-18

    The discovery of the DNA-mediated assembly of gold nanoparticles was a great moment in the history of science; this understanding and chemical control enabled the rational design of functional nanomaterials as novel probes in biodetection. In contrast with conventional probes such as organic dyes, gold nanoparticles exhibit high photostability and unique size-dependent optical properties. Because of their high extinction coefficients and strong distance dependent optical properties, these nanoparticles have emerged over the past decade as a promising platform for rapid, highly sensitive colorimetric assays that allow for the visual detection of low concentrations of metal ions, small molecules, and biomacromolecules. These discoveries have deepened our knowledge of biological phenomena and facilitated the development of many new diagnostic and therapeutic tools. Despite these many advances and continued research efforts, current nanoparticle-based colorimetric detection systems still suffer from several drawbacks, such as limited sensitivity and selectivity. This Account describes the recent development of colorimetric assays based on protein enzyme-assisted gold nanoparticle amplification. The benefits of such detection systems include significantly improved detection sensitivity and selectivity. First, we discuss the general design of enzyme-modified nanoparticle systems in colorimetric assays. We show that a quantitative understanding of the unique properties of different enzymes is paramount for effective biological assays. We then examine the assays for nucleic acid detection based on different types of enzymes, including endonucleases, ligases, and polymerases. For each of these assays, we identify the underlying principles that contribute to the enhanced detection capability of nanoparticle systems and illustrate them with selected examples. Furthermore, we demonstrate that the combination of gold nanoparticles and specific enzymes can probe enzyme dynamics

  8. Effects of non-enzymatic glycation in human serum albumin. Spectroscopic analysis

    Science.gov (United States)

    Szkudlarek, A.; Sułkowska, A.; Maciążek-Jurczyk, M.; Chudzik, M.; Równicka-Zubik, J.

    2016-01-01

    Human serum albumin (HSA), transporting protein, is exposed during its life to numerous factors that cause its functions become impaired. One of the basic factors - glycation of HSA - occurs in diabetes and may affect HSA-drug binding. Accumulation of advanced glycation end-products (AGEs) leads to diseases e.g. diabetic and non-diabetic cardiovascular diseases, Alzheimer disease, renal disfunction and in normal aging. The aim of the present work was to estimate how non-enzymatic glycation of human serum albumin altered its tertiary structure using fluorescence technique. We compared glycated human serum albumin by glucose (gHSAGLC) with HSA glycated by fructose (gHSAFRC). We focused on presenting the differences between gHSAFRC and nonglycated (HSA) albumin used acrylamide (Ac), potassium iodide (KI) and 2-(p-toluidino)naphthalene-6-sulfonic acid (TNS). Changes of the microenvironment around the tryptophan residue (Trp-214) of non-glycated and glycated proteins was investigated by the red-edge excitation shift method. Effect of glycation on ligand binding was examined by the binding of phenylbutazone (PHB) and ketoprofen (KP), which a primary high affinity binding site in serum albumin is subdomain IIA and IIIA, respectively. At an excitation and an emission wavelength of λex 335 nm and λem 420 nm, respectively the increase of fluorescence intensity and the blue-shift of maximum fluorescence was observed. It indicates that the glycation products decreases the polarity microenvironment around the fluorophores. Analysis of red-edge excitation shift method showed that the red-shift for gHSAFRC is higher than for HSA. Non-enzymatic glycation also caused, that the Trp residue of gHSAFRC becomes less accessible for the negatively charged quencher (I-), KSV value is smaller for gHSAFRC than for HSA. TNS fluorescent measurement demonstrated the decrease of hydrophobicity in the glycated albumin. KSV constants for gHSA-PHB systems are higher than for the unmodified serum

  9. Comparative evaluation of various solid phases for the development of coated tube assays for the estimation of progesterone in human serum, bovine serum and bovine milk

    International Nuclear Information System (INIS)

    Karir, Tarveen; Samuel, Grace; Sivaprasad, N.; Venkatesh, Meera

    2009-01-01

    Immobilization of progesterone antibody using three polystyrene surfaces and two progesterone radiotracers for use in the development of a coated tube assay for the evaluation of progesterone levels in human serum, bovine serum and bovine milk was studied. The selection of the solid phase and the tracers were based on the maximum binding, non-specific binding, sensitivity and percentage recovery. Amongst the polystyrene tubes studied, streptavidin coated tubes showed the acceptable assay features such as low non-specific binding (0.5-1.0%), adequate sensitivity (0.13-0.16 ng/ml) and recovery (85-115%) for all the three sample matrices, human serum, bovine serum and bovine milk.

  10. Electrochemical Studies of Camptothecin and Its Interaction with Human Serum Albumin

    OpenAIRE

    Zhao, Jing; Zheng, Xiaofeng; Xing, Wei; Huang, Junyi; Li, Genxi

    2007-01-01

    Camptothecin, an anticancer component from Camptotheca acuminate, may interact with human serum albumin (HSA) at the subdomain IIA (site I), and then convert to its inactive form(carboxylate form). In this paper, the detailed electrochemical behaviors of camptothecin at a pyrolytic graphite electrode is presented. The interaction between camptothecin and HSA is also studied by electrochemical technique. By comparing with bovine serum albumin (BSA), which is highly homologous to HSA, we prove ...

  11. Resveratrol-loaded glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles: Preparation, characterization, and targeting effect on liver tumors.

    Science.gov (United States)

    Wu, Mingfang; Lian, Bolin; Deng, Yiping; Feng, Ziqi; Zhong, Chen; Wu, Weiwei; Huang, Yannian; Wang, Lingling; Zu, Chang; Zhao, Xiuhua

    2017-08-01

    In this study, glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles were prepared to establish a tumor targeting nano-sized drug delivery system. Glycyrrhizic acid was coupled to human serum albumin, and resveratrol was encapsulated in glycyrrhizic acid-conjugated human serum albumin by high-pressure homogenization emulsification. The average particle size of sample nanoparticles prepared under the optimal conditions was 108.1 ± 5.3 nm with a polydispersity index (PDI) of 0.001, and the amount of glycyrrhizic acid coupled with human serum albumin was 112.56 µg/mg. The drug encapsulation efficiency and drug loading efficiency were 83.6 and 11.5%, respectively. The glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles were characterized through laser light scattering, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analyses, and gas chromatography. The characterization results showed that resveratrol in glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles existed in amorphous state and the residual amounts of chloroform and methanol in nanoparticles were separately less than the international conference on harmonization (ICH) limit. The in vitro drug-release study showed that the nanoparticles released the drug slowly and continuously. The inhibitory rate of glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2 H-tetrazolium bromide method. The IC50 values of glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles and resveratrol were 62.5 and 95.5 µg/ml, respectively. The target ability of glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles

  12. Activation of lipoprotein lipase by lipoprotein fractions of human serum.

    Science.gov (United States)

    Bier, D M; Havel, R J

    1970-11-01

    Triglycerides in fat emulsions are hydrolyzed by lipoprotein lipase only when they are "activated" by serum lipoproteins. The contribution of different lipoprotein fractions to hydrolysis of triglycerides in soybean oil emulsion was assessed by determining the quantity of lipoprotein fraction required to give half-maximal hydrolysis. Most of the activator property of whole serum from normolipidemic, postabsorptive subjects was in high density lipoproteins. Low density lipoproteins and serum from which all lipoprotein classes were removed had little or no activity. Also, little activator was present in guinea pig serum or in very low density poor serum from an individual with lecithin:cholesterol acyltransferase deficiency, both of which are deficient in high density lipoproteins. Human very low density lipoproteins are potent activators and are much more active than predicted from their content of high density lipoprotein-protein. Per unit weight of protein, very low density lipoproteins had 13 times the activity of high density lipoproteins. These observations suggest that one or more of the major apoproteins of very low density lipoproteins, present as a minor constituent of high density lipoproteins, may be required for the activation process.

  13. Opium and heroin alter biochemical parameters of human's serum.

    Science.gov (United States)

    Kouros, Divsalar; Tahereh, Haghpanah; Mohammadreza, Afarinesh; Minoo, Mahmoudi Zarandi

    2010-05-01

    Iran is a significant consumer of opium, and, generally, of opioids, in the world. Addiction is one of the important issues of the 21st century and is an imperative issue in Iran. Long-term consumption of opioids affects homeostasis. To determine the effects of opium and heroin consumption on serum biochemical parameters. In a cross-sectional study, subjects who had consumed heroin (n = 35) or opium (n = 42) for more than two years and 35 nonaddict volunteers as the control group were compared in regard to various biochemical parameters such as fasting blood sugar (FBS), Na(+), K(+), Ca(2+), blood urea nitrogen (BUN), uric acid (UA), triglyceride (TG), cholesterol, creatinine, and total protein. Chromatography was used to confirm opioid consumption, and the concentration of biochemical parameters was determined by laboratory diagnostic tests on serum. No significant differences were found in Na(+), Ca(2+), BUN, UA, TG, creatinine, and total protein concentrations among the three groups. FBS, K(+), and UA levels were significantly lower in opium addicts compared to the control group. Serum Ca(2+) concentration of heroin addicts showed a significant decrease compared to that of the control group. Both addict groups showed a significant decrease in serum cholesterol levels. Chronic use of opium and heroin can change serum FBS, K(+), Ca(2+), UA, and cholesterol. This study, one of few on the effects of opium on serum biochemical parameters in human subjects, has the potential to contribute to the investigation of new approaches for further basic studies.

  14. Facile colorimetric assay of alkaline phosphatase activity using Fe(II)-phenanthroline reporter.

    Science.gov (United States)

    Hu, Qiong; Zhou, Baojing; Dang, Pengyun; Li, Lianzhi; Kong, Jinming; Zhang, Xueji

    2017-01-15

    We report a versatile approach for the colorimetric assay of alkaline phosphatase (ALP) activity based on the distinctive metal-to-ligand charge-transfer (MLCT) absorption properties of Fe(II)-phenanthroline reporter. In the presence of ALP, the applied substrate ascorbic acid 2-phosphate is enzymatically hydrolyzed to produce ascorbic acid, which then reduces Fe 3+ to Fe 2+ . The complexation of Fe 2+ with the bathophenanthroline disulfonate (BPS) ligand generates a blood-red Fe(BPS) 3 4- reporter, which is characterized by an intense MLCT absorption band at 535 nm in the visible range. Under optimal conditions, the spectral output exhibits a good quantitative relationship with ALP activity over the range of 0-220 mU mL -1 with a detection limit of 0.94 mU mL -1 . Moreover, the activity of ALP can also be conveniently judged through naked-eye observations. Results indicate that it is highly selective and can be applied to the screening of ALP inhibitors. In addition, it has been successfully employed to detect the endogenous ALP level of undiluted human serum samples, with a detection limit of 1.05 mU mL -1 being achieved. This approach avoids any elaborately designed substrates and holds considerable simplicity and flexibility for reporter design. This study broadens the horizon of the applications of phenanthroline-based transition metal complexes. Furthermore, an efficient and practical method like this has the potential to be widely used in clinical applications and in the point-of-care testing. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Photo-physical and structural interactions between viologen phosphorus-based dendrimers and human serum albumin

    International Nuclear Information System (INIS)

    Ciepluch, Karol; Katir, Nadia; El Kadib, Abdelkrim; Weber, Monika; Caminade, Anne-Marie; Bousmina, Mostapha; Pierre Majoral, Jean; Bryszewska, Maria

    2012-01-01

    This work deals with photo-physical and structural interactions between viologen phosphorus dendrimers and human serum albumin (HSA). Viologens are derivatives of 4,4′-bipyridinium salts. Aiming to rationalize the parameters governing such interactions eight types of these polycationic dendrimers in which the generation, the number of charges, the nature of the core and of the terminal groups vary from one to another, were designed and used. The influence of viologen-based dendrimers' on human serum albumin has been investigated. The photo-physical interactions of the two systems have been monitored by fluorescence quenching of free L-tryptophan and of HSA tryptophan residue. Additionally, using circular dichroism (CD) the effect of dendrimers on the secondary structure of albumin was measured. The obtained results show that viologen dendrimers interact with human serum albumin quenching its fluorescence either by collisional (dynamic) way or by forming complexes in a ground state (static quenching). In some cases the quenching is accompanied by changes of the secondary structure of HSA. - Highlights: ► Photo-physical interactions between viologen phosphorus dendrimers and human serum albumin (HSA) were investigated. ► The viologen dendrimers can quench the fluorescence of tryptophan in HSA. ► CD spectra to explain the changes in secondary structure of albumin after exposition of dendrimers.

  16. Colorimetric characterization of LED luminaires

    International Nuclear Information System (INIS)

    Costa, C L M; Vieira, R R; Pereira, R C; Silva, P V M; Oliveira, I A A; Sardinha, A S; Viana, D D; Barbosa, A H; Souza, L P; Alvarenga, A D

    2015-01-01

    The Optical Metrology Division of Inmetro – National Institute of Metrology, Quality and Technology has recently started the colorimetric characterization of lamps by implementing Correlated Color Temperature (CCT) and Color Rendering Index (CRI) measurements of incandescent lamps, followed by the CFL, and LED lamps and luminaires. Here we present the results for the verification of the color characterization of samples of SSL luminaires for public as well as indoor illumination that are sold in Brazil

  17. Power Harvesting from Human Serum in Buckypaper-Based Enzymatic Biofuel Cell

    Energy Technology Data Exchange (ETDEWEB)

    Güven, Güray, E-mail: gguven@ginerinc.com [Giner, Inc., Newton, MA (United States); Şahin, Samet [Pennsylvania State University College of Medicine, Hershey, PA (United States); Güven, Arcan [Chemical Engineering and Advanced Materials, Merz Court, Newcastle University, Newcastle upon Tyne (United Kingdom); Yu, Eileen H., E-mail: gguven@ginerinc.com [Pennsylvania State University College of Medicine, Hershey, PA (United States)

    2016-02-16

    The requirement for a miniature, high density, long life, and rechargeable power source is common to a vast majority of microsystems, including the implantable devices for medical applications. A model biofuel cell system operating in human serum has been studied for future applications of biomedical and implantable medical devices. Anodic and cathodic electrodes were made of carbon nanotube-buckypaper modified with PQQ-dependent glucose dehydrogenase and laccase, respectively. Modified electrodes were characterized electrochemically and assembled in a biofuel cell setup. Power density of 16.12 μW cm{sup −2} was achieved in human serum for lower than physiological glucose concentrations. Increasing the glucose concentration and biofuel cell temperature caused an increase in power output leading up to 49.16 μW cm{sup −2}.

  18. Colorimetric measurements as control elements in wood conservation status

    Directory of Open Access Journals (Sweden)

    Ovidia Soto-Martín

    2014-01-01

    Full Text Available This paper is a methodological proposal for the study of altarpieces on wooden supports. The process was implemented to study the altarpiece of San Antonio de Padua in Garachico, Tenerife. For this, we conducted a review of key aspects appropriate to the discipline of wood identification carried out by macroscopic examination and for the characterization of the status of deterioration by colorimetric analysis. For the evaluation of the wood conservation status, the samples were subjected for the first time to colorimetric measurement. As a result we have created an online database to provide information for conservation professionals permitting them to design a proposal for preventive conservation and intervention individually for each object.

  19. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles

    International Nuclear Information System (INIS)

    Shen, Li; Chen, Jing; Li, Na; He, Pingli; Li, Zhen

    2014-01-01

    Highlights: • Tetracyclines directly reduce aurate into gold nanoparticles. • Gold nanoparticles showed characteristic plamson absorbance at 526 nm. • Quantitative detection of tetracyclines with the colorimetric assay. • Tetracyclines spiked urine samples can be detected with the assay. - Abstract: A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV–vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL −1 can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples

  20. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Li [Logistics School, Beijing Wuzi University, Beijing 101149 (China); Chen, Jing; Li, Na [Logistics School, Beijing Wuzi University, Beijing 101149 (China); He, Pingli [State Key Laboratory of Animal Nutrition, China Agricultural University, Beijing 100094 (China); Li, Zhen [State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193 (China)

    2014-08-11

    Highlights: • Tetracyclines directly reduce aurate into gold nanoparticles. • Gold nanoparticles showed characteristic plamson absorbance at 526 nm. • Quantitative detection of tetracyclines with the colorimetric assay. • Tetracyclines spiked urine samples can be detected with the assay. - Abstract: A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV–vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL{sup −1} can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples.

  1. Clonogenic growth of human breast cancer cells co-cultured in direct contact with serum-activated fibroblasts

    International Nuclear Information System (INIS)

    Samoszuk, Michael; Tan, Jenny; Chorn, Guillaume

    2005-01-01

    Accumulating evidence suggests that fibroblasts play a pivotal role in promoting the growth of breast cancer cells. The objective of the present study was to characterize and validate an in vitro model of the interaction between small numbers of human breast cancer cells and human fibroblasts. We measured the clonogenic growth of small numbers of human breast cancer cells co-cultured in direct contact with serum-activated, normal human fibroblasts. Using DNA microarrays, we also characterized the gene expression profile of the serum-activated fibroblasts. In order to validate the in vivo relevance of our experiments, we then analyzed clinical samples of metastatic breast cancer for the presence of myofibroblasts expressing α-smooth muscle actin. Clonogenic growth of human breast cancer cells obtained directly from in situ and invasive tumors was dramatically and consistently enhanced when the tumor cells were co-cultured in direct contact with serum-activated fibroblasts. This effect was abolished when the cells were co-cultured in transwells separated by permeable inserts. The fibroblasts in our experimental model exhibited a gene expression signature characteristic of 'serum response' (i.e. myofibroblasts). Immunostaining of human samples of metastatic breast cancer tissue confirmed that myofibroblasts are in direct contact with breast cancer cells. Serum-activated fibroblasts promote the clonogenic growth of human breast cancer cells in vitro through a mechanism that involves direct physical contact between the cells. This model shares many important molecular and phenotypic similarities with the fibroblasts that are naturally found in breast cancers

  2. Simultaneous quantitation of multiple contraceptive hormones in human serum by LC-MS/MS.

    Science.gov (United States)

    Blue, Steven W; Winchell, Andrea J; Kaucher, Amy V; Lieberman, Rachel A; Gilles, Christopher T; Pyra, Maria N; Heffron, Renee; Hou, Xuanlin; Coombs, Robert W; Nanda, Kavita; Davis, Nicole L; Kourtis, Athena P; Herbeck, Joshua T; Baeten, Jared M; Lingappa, Jairam R; Erikson, David W

    2018-04-01

    The objective was to develop a method to simultaneously quantify five commonly used hormonal contraceptives (HCs) and two endogenous sex steroids by liquid chromatography-tandem triple quadrupole mass spectrometry (LC-MS/MS) and apply this method to human serum samples. We developed a method to simultaneously analyze ethinyl estradiol (EE2), etonogestrel (ENG), levonorgestrel (LNG), medroxyprogesterone acetate (MPA) and norethisterone (NET), along with estradiol (E2) and progesterone (P4), in human serum for a Shimadzu Nexera-LCMS-8050 LC-MS/MS platform. We analyzed serum collected from women self-reporting use of oral contraceptives, contraceptive implants or injectable contraceptives (n=14) and normally cycling women using no HC (n=15) as well as pooled samples from women administered various HCs (ENG, n=6; LNG, n=14; MPA, n=7; NET, n=5). Limits of quantitation were 0.010ng/mL for E2, EE2 and P4; 0.020ng/mL for ENG, LNG and MPA; and 0.040ng/mL for NET. Precisions for all assays, as indicated by coefficient of variation, were less than or equal to 12.1%. Accuracies for all assays were in the range of 95%-108%. Endogenous hormone values obtained from analysis of human serum samples are in agreement with levels previously reported in the literature for normally cycling women as well as for women taking the appropriate HC. We have developed a robust, accurate and sensitive method for simultaneously analyzing commonly used contraceptive steroids and endogenous sex steroids in human serum. This analytical method can be used for quantitating contraceptive steroid levels in women for monitoring systemic exposure to determine drug interactions, nonadherence, misreporting and proper dosing. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. New turn-on fluorescent and colorimetric probe for cyanide detection based on BODIPY-salicylaldehyde and its application in cell imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sukato, Rangsarit [Program of Petrochemistry and Polymer Science, Chulalongkorn University, Bangkok 10330 (Thailand); Sangpetch, Nuanphan; Palaga, Tanapat [Department of Microbiology, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330 (Thailand); Jantra, Suthikorn; Vchirawongkwin, Viwat; Jongwohan, Chanantida [Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand); Sukwattanasinitt, Mongkol [Nanotec-CU Center of Excellence on Food and Agriculture, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand); Wacharasindhu, Sumrit, E-mail: sumrit.w@chula.ac.th [Nanotec-CU Center of Excellence on Food and Agriculture, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand)

    2016-08-15

    Highlights: • A novel salicylaldehyde-BODIPY fluorescent sensor is prepared. • The sensor shows dual colorimetric & turn-on fluorescence response to cyanide ion. • Detection limit is 0.88 μM (below WHO standard for drinking water). • It is effective for cyanide detection an in vitro cellular system. - Abstract: Development of cyanide sensor is important as the anion is harmful to human health and the environment. Herein, a new colorimetric and fluorescent probe GSB based on boron dipyrrole-methene (BODIPY) containing salicylaldehyde group for cyanide detection has been reported. GSB undergoes exclusive colorimetric change from orange to colorless and exhibits selective fluorescence turn-on at 504 nm upon the addition of cyanide. Other 13 anions give almost no interference under physiological condition. Detection limit of the new cyanide-sensing GSB is 0.88 μM, which is below World Health Organization (WHO) recommended level in drinking water. A calculation by density functional theory (DFT) shows suppression of photoinduced electron transfer (PET) mechanism along with the interruption of π-conjugation between salicylaldehyde and BODIPY core by cyanide anion. Cell imaging studies demonstrated that GSB is compatible and capable of sensing cyanide anion in living cells.

  4. New turn-on fluorescent and colorimetric probe for cyanide detection based on BODIPY-salicylaldehyde and its application in cell imaging

    International Nuclear Information System (INIS)

    Sukato, Rangsarit; Sangpetch, Nuanphan; Palaga, Tanapat; Jantra, Suthikorn; Vchirawongkwin, Viwat; Jongwohan, Chanantida; Sukwattanasinitt, Mongkol; Wacharasindhu, Sumrit

    2016-01-01

    Highlights: • A novel salicylaldehyde-BODIPY fluorescent sensor is prepared. • The sensor shows dual colorimetric & turn-on fluorescence response to cyanide ion. • Detection limit is 0.88 μM (below WHO standard for drinking water). • It is effective for cyanide detection an in vitro cellular system. - Abstract: Development of cyanide sensor is important as the anion is harmful to human health and the environment. Herein, a new colorimetric and fluorescent probe GSB based on boron dipyrrole-methene (BODIPY) containing salicylaldehyde group for cyanide detection has been reported. GSB undergoes exclusive colorimetric change from orange to colorless and exhibits selective fluorescence turn-on at 504 nm upon the addition of cyanide. Other 13 anions give almost no interference under physiological condition. Detection limit of the new cyanide-sensing GSB is 0.88 μM, which is below World Health Organization (WHO) recommended level in drinking water. A calculation by density functional theory (DFT) shows suppression of photoinduced electron transfer (PET) mechanism along with the interruption of π-conjugation between salicylaldehyde and BODIPY core by cyanide anion. Cell imaging studies demonstrated that GSB is compatible and capable of sensing cyanide anion in living cells.

  5. Visualizing Capsaicinoids: Colorimetric Analysis of Chili Peppers

    Science.gov (United States)

    Thompson, Robert Q.; Chu, Christopher; Gent, Robin; Gould, Alexandra P.; Rios, Laura; Vertigan, Theresa M.

    2012-01-01

    A colorimetric method for total capsaicinoids in chili pepper ("Capsicum") fruit is described. The placental material of the pepper, containing 90% of the capsaicinoids, was physically separated from the colored materials in the pericarp and extracted twice with methanol, capturing 85% of the remaining capsaicinoids. The extract, evaporated and…

  6. Spectrophotometric assay of creatinine in human serum sample

    Directory of Open Access Journals (Sweden)

    Avinash Krishnegowda

    2017-05-01

    Full Text Available A new spectrophotometric method for the analysis of creatinine concentration in human serum samples is developed. The method explores the oxidation of p-methylamino phenol sulfate (Metol in the presence of copper sulfate and creatinine which yields an intense violet colored species with maximum absorbance at 530 nm. The calibration graph of creatinine by fixed time assay ranged from 4.4 to 620 μM. Recovery of creatinine in human serum samples varied from 101% to 106%. Limit of detection and limit of quantification were 0.145 μM and 0.487 μM respectively. Sandell’s sensitivity was 0.112 μg cm−2 and molar absorptivity was 0.101 × 104 L mol−1 cm−1. Within day precision was 2.5–4.8% and day-to-day precision range was 3.2–7.8%. The robustness and ruggedness of the method expressed in RSD values ranged from 0.78% to 2.12% and 1.32% to 3.46% respectively, suggesting that the developed method was rugged. This method provides good sensitivity and is comparable to standard Jaffe’s method with comparatively less interference from foreign substances.

  7. Photo-physical and structural interactions between viologen phosphorus-based dendrimers and human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Ciepluch, Karol, E-mail: ciepluch@biol.uni.lodz.pl [Department of General Biophysics, University of Lodz, 141/143 Pomorska St., 90-236 Lodz (Poland); Katir, Nadia [Laboratoire de Chimie de Coordination du CNRS (LCC), 205 route de Narbonne, F-31077 Toulouse cedex 4 (France); Institute of Nanomaterials and Nanotechnology (INANOTECH)-MAScIR (Moroccan Foundation for Advanced Science, Innovation and Research), ENSET, Avenue de l' Armee Royale, Madinat El Irfane, 10100 Rabat (Morocco); El Kadib, Abdelkrim [Institute of Nanomaterials and Nanotechnology (INANOTECH)-MAScIR (Moroccan Foundation for Advanced Science, Innovation and Research), ENSET, Avenue de l' Armee Royale, Madinat El Irfane, 10100 Rabat (Morocco); Weber, Monika [Department of General Biophysics, University of Lodz, 141/143 Pomorska St., 90-236 Lodz (Poland); Caminade, Anne-Marie [Laboratoire de Chimie de Coordination du CNRS (LCC), 205 route de Narbonne, F-31077 Toulouse cedex 4 (France); Bousmina, Mostapha [Hassan II Academy of Sciences and Technology, Avenue MVI, Km4, 10220 Rabat (Morocco); Pierre Majoral, Jean [Laboratoire de Chimie de Coordination du CNRS (LCC), 205 route de Narbonne, F-31077 Toulouse cedex 4 (France); Hassan II Academy of Sciences and Technology, Avenue MVI, Km4, 10220 Rabat (Morocco); Bryszewska, Maria [Department of General Biophysics, University of Lodz, 141/143 Pomorska St., 90-236 Lodz (Poland)

    2012-06-15

    This work deals with photo-physical and structural interactions between viologen phosphorus dendrimers and human serum albumin (HSA). Viologens are derivatives of 4,4 Prime -bipyridinium salts. Aiming to rationalize the parameters governing such interactions eight types of these polycationic dendrimers in which the generation, the number of charges, the nature of the core and of the terminal groups vary from one to another, were designed and used. The influence of viologen-based dendrimers' on human serum albumin has been investigated. The photo-physical interactions of the two systems have been monitored by fluorescence quenching of free L-tryptophan and of HSA tryptophan residue. Additionally, using circular dichroism (CD) the effect of dendrimers on the secondary structure of albumin was measured. The obtained results show that viologen dendrimers interact with human serum albumin quenching its fluorescence either by collisional (dynamic) way or by forming complexes in a ground state (static quenching). In some cases the quenching is accompanied by changes of the secondary structure of HSA. - Highlights: Black-Right-Pointing-Pointer Photo-physical interactions between viologen phosphorus dendrimers and human serum albumin (HSA) were investigated. Black-Right-Pointing-Pointer The viologen dendrimers can quench the fluorescence of tryptophan in HSA. Black-Right-Pointing-Pointer CD spectra to explain the changes in secondary structure of albumin after exposition of dendrimers.

  8. X-ray and neutron small-angle scattering studies of human serum lipoproteins

    International Nuclear Information System (INIS)

    Luzzati, V.; Tardieu, A.; Mateu, L.; Sardet, C.; Stuhrmann, H.B.; Aggerbeck, L.; Scanu, A.M.

    1976-01-01

    The paper describes an extended x-ray study of two types of human serum lipoproteins and a neutron study of one of them. The results are similar and to some extent complementary. Serum lipoproteins provide an excellent illustration of the wealth of information that can be obtained by a small-angle scattering approach to the structure of particles with non-uniform density distribution, by using solvents of variable density

  9. Hydrolysis of pyrethroids by human and rat tissues: Examination of intestinal, liver and serum carboxylesterases

    International Nuclear Information System (INIS)

    Crow, J. Allen; Borazjani, Abdolsamad; Potter, Philip M.; Ross, Matthew K.

    2007-01-01

    Hydrolytic metabolism of pyrethroid insecticides in humans is one of the major catabolic pathways that clear these compounds from the body. Rodent models are often used to determine the disposition and clearance rates of these esterified compounds. In this study the distribution and activities of esterases that catalyze pyrethroid metabolism have been investigated in vitro using several human and rat tissues, including small intestine, liver and serum. The major esterase in human intestine is carboxylesterase 2 (hCE2). We found that the pyrethroid trans-permethrin is effectively hydrolyzed by a sample of pooled human intestinal microsomes (5 individuals), while deltamethrin and bioresmethrin are not. This result correlates well with the substrate specificity of recombinant hCE2 enzyme. In contrast, a sample of pooled rat intestinal microsomes (5 animals) hydrolyze trans-permethrin 4.5-fold slower than the sample of human intestinal microsomes. Furthermore, it is demonstrated that pooled samples of cytosol from human or rat liver are ∼ 2-fold less hydrolytically active (normalized per mg protein) than the corresponding microsomal fraction toward pyrethroid substrates; however, the cytosolic fractions do have significant amounts (∼ 40%) of the total esteratic activity. Moreover, a 6-fold interindividual variation in carboxylesterase 1 protein expression in human hepatic cytosols was observed. Human serum was shown to lack pyrethroid hydrolytic activity, but rat serum has hydrolytic activity that is attributed to a single CE isozyme. We purified the serum CE enzyme to homogeneity to determine its contribution to pyrethroid metabolism in the rat. Both trans-permethrin and bioresmethrin were effectively cleaved by this serum CE, but deltamethrin, esfenvalerate, alpha-cypermethrin and cis-permethrin were slowly hydrolyzed. Lastly, two model lipase enzymes were examined for their ability to hydrolyze pyrethroids. However, no hydrolysis products could be detected

  10. Comparison of macro-gravimetric and micro-colorimetric lipid determination methods.

    Science.gov (United States)

    Inouye, Laura S; Lotufo, Guiherme R

    2006-10-15

    In order to validate a method for lipid analysis of small tissue samples, the standard macro-gravimetric method of Bligh-Dyer (1959) [E.G. Bligh, W.J. Dyer, Can. J. Biochem. Physiol. 37 (1959) 911] and a modification of the micro-colorimetric assay developed by Van Handel (1985) [E. Van Handel, J. Am. Mosq. Control Assoc. 1 (1985) 302] were compared. No significant differences were observed for wet tissues of two species of fish. However, limited analysis of wet tissue of the amphipod, Leptocheirusplumulosus, indicated that the Bligh-Dyer gravimetric method generated higher lipid values, most likely due to the inclusion of non-lipid materials. Additionally, significant differences between the methods were observed with dry tissues, with the micro-colorimetric method consistently reporting calculated lipid values greater than as reported by the gravimetric method. This was most likely due to poor extraction of dry tissue in the standard Bligh-Dyer method, as no significant differences were found when analyzing a single composite extract. The data presented supports the conclusion that the micro-colorimetric method described in this paper is accurate, rapid, and minimizes time and solvent use.

  11. Identification and measurement of a folate-binding protein in human serum by radioimmunoassay

    International Nuclear Information System (INIS)

    Da Costa, M.; Rothenberg, S.P.; Fischer, C.; Rosenberg, Z.

    1978-01-01

    Antiserum raised in rabbits against the FBP obtained from CML cells, and the purified binder labeled with 125 I, have been used for an RIA which can measure an immunologically similar protein in human serum. The concentration of the binding protein in normal serums ranged from 1.2 to 9.3 ng/ml, with a mean +- S.E.M. of 3.8 +- 0.4 ng/ml. Elevated values of the binder protein were measured in the serums from patients with folate deficiency, vitamin B 12 deficiency, liver disease, uremia, myeloproliferative diseases, chronic lymphocytic leukemia, and various types of cancer and in the serum from pregnant women. The concentration of the binder protein and the capacity of the serum to specifically bind isotopically labeled PGA correlated poorly, indicating that the binding protein concentration and degree of saturation by endogenous serum folate vary independently in many instances

  12. Antioxidant flavonoids bind human serum albumin

    Science.gov (United States)

    Kanakis, C. D.; Tarantilis, P. A.; Polissiou, M. G.; Diamantoglou, S.; Tajmir-Riahi, H. A.

    2006-10-01

    Human serum albumin (HSA) is a principal extracellular protein with a high concentration in blood plasma and carrier for many drugs to different molecular targets. Flavonoids are powerful antioxidants and prevent DNA damage. The antioxidative protections are related to their binding modes to DNA duplex and complexation with free radicals in vivo. However, flavonoids are known to inhibit the activities of several enzymes such as calcium phospholipid-dependent protein kinase, tyrosine protein kinase from rat lung, phosphorylase kinase, phosphatidylinositol 3-kinase and DNA topoisomerases that exhibit the importance of flavonoid-protein interaction. This study was designed to examine the interaction of human serum albumin (HSA) with quercetin (que), kaempferol (kae) and delphinidin (del) in aqueous solution at physiological conditions, using constant protein concentration of 0.25 mM (final) and various drug contents of 1 μM-1 mM. FTIR and UV-vis spectroscopic methods were used to determine the polyphenolic binding mode, the binding constant and the effects of flavonoid complexation on protein secondary structure. The spectroscopic results showed that flavonoids are located along the polypeptide chains through H-bonding interactions with overall affinity constant of Kque = 1.4 × 10 4 M -1, Kkae = 2.6 × 10 5 M -1 and Kdel = 4.71 × 10 5 M -1. The protein secondary structure showed no alterations at low pigment concentration (1 μM), whereas at high flavonoid content (1 mM), major reduction of α-helix from 55% (free HSA) to 42-46% and increase of β-sheet from 15% (free HSA) to 17-19% and β-anti from 7% (free HSA) to 10-20% occurred in the flavonoid-HSA adducts. The major reduction of HSA α-helix is indicative of a partial protein unfolding upon flavonoid interaction.

  13. Effect of zinc supplementation on body mass index and serum levels of zinc and leptin in pediatric hemodialysis patients

    Directory of Open Access Journals (Sweden)

    El-Shazly AN

    2015-12-01

    Full Text Available Ahmed Nabih El-Shazly,1 Soha Abd El-Hady Ibrahim,1 Ghada Mohamed El-Mashad,2 Jehan H Sabry,3 Nashwa Said Sherbini11Department of Pediatrics, Faculty of Medicine, Benha University, Banha, 2Department of Pediatrics, Faculty of Medicine, Menoufia University, Shibin Al Kawm, 3Department of Clinical and Chemical Pathology, Faculty of Medicine, Benha University, Banha, Egypt Introduction: Zinc is an essential trace element for human nutrition, and its deficiency is associated with anorexia, poor food efficiency, growth retardation, and impaired neurological and immune systems. The zinc-deficiency rate is particularly high in many disease states, such as with end-stage renal disease patients undertaking hemodialysis. The aim of this study was to determine the effect of zinc supplementation on body mass index (BMI and serum levels of zinc and leptin in pediatric hemodialysis patients. Patients and methods: This was a prospective clinical trial study in which 60 hemodialysis patients were randomly divided into two groups: group I received 50–100 mg zinc sulfate (equivalent to 11–22 mg elemental zinc according to age, sex, and nutritional status of the child; and group II received placebo (cornstarch twice daily for 90 days. Anthropometric measurements were taken, and serum zinc and leptin levels were determined by colorimetric test with 5-Br-3'-phosphoadenosine-5'-phosphosulfate and enzyme-linked immunosorbent assay, respectively, at days 0 and 90 of the study. Results: Zinc supplementation resulted in a significant increase in mean serum zinc level and BMI. Serum leptin decreased significantly after supplementation in children under hemodialysis. A significant negative correlation was observed between serum zinc and leptin levels as a result of zinc supplementation. Conclusion: There was an increase in serum zinc level and BMI and decreased serum leptin after zinc supplementation in children under hemodialysis. Keywords: serum zinc, serum leptin

  14. Single Gold Nanoparticle-Based Colorimetric Detection of Picomolar Mercury Ion with Dark-Field Microscopy.

    Science.gov (United States)

    Liu, Xiaojun; Wu, Zhangjian; Zhang, Qingquan; Zhao, Wenfeng; Zong, Chenghua; Gai, Hongwei

    2016-02-16

    Mercury severely damages the environment and human health, particularly when it accumulates in the food chain. Methods for the colorimetric detection of Hg(2+) have increasingly been developed over the past decade because of the progress in nanotechnology. However, the limits of detection (LODs) of these methods are mostly either comparable to or higher than the allowable maximum level (10 nM) in drinking water set by the US Environmental Protection Agency. In this study, we report a single Au nanoparticle (AuNP)-based colorimetric assay for Hg(2+) detection in solution. AuNPs modified with oligonucleotides were fixed on the slide. The fixed AuNPs bound to free AuNPs in the solution in the presence of Hg(2+) because of oligonucleotide hybridization. This process was accompanied by a color change from green to yellow as observed under an optical microscope. The ratio of changed color spots corresponded with Hg(2+) concentration. The LOD was determined as 1.4 pM, which may help guard against mercury accumulation. The proposed approach was applied to environmental samples with recoveries of 98.3 ± 7.7% and 110.0 ± 8.8% for Yuquan River and industrial wastewater, respectively.

  15. Solution behaviour of Human Serum Albumin and GLP-1variants

    DEFF Research Database (Denmark)

    Sønderby, Pernille

    interaction is critical for the long term stability of a pharmaceutical. Protein complex formation is important for extended half-life in vivo and is essential to cellular communication such as the induction of the insulin response. This thesis focuses on human serum albumin (HSA) as a central player...

  16. Development of a radioimmunoassay for the measurement of human leptin in serum

    International Nuclear Information System (INIS)

    Lagarde, A. R.; Nagy, K.; Forgach, T.; Janoki, G. A.

    2003-01-01

    Leptin is a 16 kDa polypeptide hormone encoded by the obese gene (ob) and secreted by adipose tissue. This hormone plays a major role in energy homeostasis and regulation of food intake and body weight. It also affects the metabolic, neuroendocrine and reproductive systems. Labelling of recombinant human leptin with 125I was best performed by the Chloramine-T method. New Zealand white rabbits were immunised with recombinant human leptin, cross-reaction of obtained antisera was analyzed with 10 different antigens. The separation of bound and free fractions was performed using the second antibody - PEG method. The obtained tracer had specific activities of 2.8-3.3 kBq/μg and had a stability of 5 weeks. A highly specific polyclonal antibody was obtained without measurable cross-reaction against the analysed antigens. Concentrations of human leptin were measured by a single overnight incubation assay with a sensitivity of 0.5 ng/ml and a measuring range of 0.5-100 ng/ml. The intra-assay and inter-assay coefficient of variation was under 6% and 8%, respectively. Recovery ranged from 88% to 106%. Serum human leptin concentrations can be accurately and precisely measured by this new radioimmunoassay. Preliminary results obtained from the measurement of serum leptin in lean, overweight and obese patients are presented. Serum leptin concentrations correlated with body mass index and were significantly higher in women than in men, except for obese patients. (author)

  17. Trace element analysis of human blood serum by neutron activation analysis

    International Nuclear Information System (INIS)

    Nakahara, H.; Nagame, Y.; Yoshizawa, Y.; Oda, H.; Gotoh, S.; Murakami, Y.

    1979-01-01

    An attempt was made to determine if there is any correlation between trace element concentrations in human blood serum and some specific diseases. The serum samples of the patients suffering from cancer, Down syndrome, and Banti syndrome were analyzed by the neutron activation method and compared with the trace element concentrations observed among clinically healthy men. The cancer patients had concentrations in Rb, Mn, Fe, Co, Cu, Zn, Al and Se below normal. The Down syndrome patients were found to have similar deficiencies in Cr, Mn, Fe, Co, Zn, Cu and Sb. (author)

  18. O2-mediated oxidation of ferrous nitrosylated human serum heme-albumin is limited by nitrogen monoxide dissociation

    International Nuclear Information System (INIS)

    Ascenzi, Paolo; Gullotta, Francesca; Gioia, Magda; Coletta, Massimo; Fasano, Mauro

    2011-01-01

    Research highlights: → Human serum heme-albumin displays globin-like properties. → O 2 -mediated oxidation of ferrous nitrosylated human serum heme-albumin. → Allosteric modulation of human serum heme-albumin reactivity. → Rifampicin is an allosteric effector of human serum heme-albumin. → Human serum heme-albumin is a ROS and NOS scavenger. -- Abstract: Human serum heme-albumin (HSA-heme-Fe) displays globin-like properties. Here, kinetics of O 2 -mediated oxidation of ferrous nitrosylated HSA-heme-Fe (HSA-heme-Fe(II)-NO) is reported. Values of the first-order rate constants for O 2 -mediated oxidation of HSA-heme-Fe(II)-NO (i.e., for ferric HSA-heme-Fe formation) and for NO dissociation from HSA-heme-Fe(II)-NO (i.e., for NO replacement by CO) are k = 9.8 x 10 -5 and 8.3 x 10 -4 s -1 , and h = 1.3 x 10 -4 and 8.5 x 10 -4 s -1 , in the absence and presence of rifampicin, respectively, at pH = 7.0 and T = 20.0 o C. The coincidence of values of k and h indicates that NO dissociation represents the rate limiting step of O 2 -mediated oxidation of HSA-heme-Fe(II)-NO. Mixing HSA-heme-Fe(II)-NO with O 2 does not lead to the formation of the transient adduct(s), but leads to the final ferric HSA-heme-Fe derivative. These results reflect the fast O 2 -mediated oxidation of ferrous HSA-heme-Fe and highlight the role of drugs in modulating allosterically the heme-Fe-atom reactivity.

  19. The distribution of iron between the metal-binding sites of transferrin human serum.

    Science.gov (United States)

    Williams, J; Moreton, K

    1980-02-01

    The Makey & Seal [(1976) Biochim. Biophys. Acta 453, 250--256] method of polyacrylamide-gel electrophoresis in buffer containing 6 M-urea was used to determine the distribution of iron between the N-terminal and C-terminal iron-binding sites of transferrin in human serum. In fresh serum the two sites are unequally occupied; there is preferential occupation of the N-terminal site. On incubation of the serum at 37 degrees C the preference of iron for the N-terminal site becomes more marked. On storage of serum at -15 degrees C the iron distribution changes so that there is a marked preference for the C-terminal site. Dialysis of serum against buffer at pH 7.4 also causes iron to be bound much more strongly by the C-terminal than by the N-terminal site. The original preference for the N-terminal site can be resroted to the dialysed serum by addition of the diffusible fraction.

  20. New generation in process-control colorimetric instrumentation

    Science.gov (United States)

    Ladson, Jack A.

    1992-08-01

    Colorimetric performance parameters (repeatability and reproducibility) of a new spectrophotometer/colorimeter manufactured by BYK-Gardner, Inc. are reported. The color- viewTM spectrophotometer (CVS) uses forty-five degree illumination and zero degree viewing geometry relative to the plane of the test specimen. The CVS is designed for the measurement of diffuse reflectance factor. It is designed to conform to national and international recommendations for Spectrophotometry and Colorimetry. Colorimetric performance was evaluated by measuring colored tiles manufactured by the British Ceramic Research Association (BCRA). Instrument repeatability was recorded after an hour, eight hours, and thirty days. Routine performance of the CVS shows that color difference repeatability over short and medium time periods is within 0.15 CIELAB color difference unit. The long term repeatability is within 0.4 unit. Reproducibility was evaluated by making color measurements on BCRA tiles with 54 instruments. Measurements made on CVS instruments indicate that its reproducibility is better than the reproducibility of product standards. Reproducibility is well within the requirement for industrial applications. Actually, the repeatability and reproducibility is comparable to that of reference instruments in national standardizing laboratories.

  1. Needle Decompression of Tension Pneumothorax with Colorimetric Capnography.

    Science.gov (United States)

    Naik, Nimesh D; Hernandez, Matthew C; Anderson, Jeff R; Ross, Erika K; Zielinski, Martin D; Aho, Johnathon M

    2017-11-01

    The success of needle decompression for tension pneumothorax is variable, and there are no objective measures assessing effective decompression. Colorimetric capnography, which detects carbon dioxide present within the pleural space, may serve as a simple test to assess effective needle decompression. Three swine underwent traumatically induced tension pneumothorax (standard of care, n = 15; standard of care with needle capnography, n = 15). Needle thoracostomy was performed with an 8-cm angiocatheter. Similarly, decompression was performed with the addition of colorimetric capnography. Subjective operator assessment of decompression was recorded and compared with true decompression, using thoracoscopic visualization for both techniques. Areas under receiver operating curves were calculated and pairwise comparison was performed to assess statistical significance (P pneumothorax, that is, the absence of any pathologic/space-occupying lesion, in 100% of cases (10 of 10 attempts). Standard of care needle decompression was detected by operators in 9 of 15 attempts (60%) and was detected in 3 of 10 attempts when tension pneumothorax was not present (30%). True decompression, under direct visualization with thoracoscopy, occurred 15 of 15 times (100%) with capnography, and 12 of 15 times (80%) without capnography. Areas under receiver operating curves were 0.65 for standard of care and 1.0 for needle capnography (P = .002). Needle decompression with colorimetric capnography provides a rapid, effective, and highly accurate method for eliminating operator bias for tension pneumothorax decompression. This may be useful for the treatment of this life-threatening condition. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  2. Colorimetric Characterization of Mobile Devices for Vision Applications.

    Science.gov (United States)

    de Fez, Dolores; Luque, Maria José; García-Domene, Maria Carmen; Camps, Vicente; Piñero, David

    2016-01-01

    Available applications for vision testing in mobile devices usually do not include detailed setup instructions, sacrificing rigor to obtain portability and ease of use. In particular, colorimetric characterization processes are generally obviated. We show that different mobile devices differ also in colorimetric profile and that those differences limit the range of applications for which they are most adequate. The color reproduction characteristics of four mobile devices, two smartphones (Samsung Galaxy S4, iPhone 4s) and two tablets (Samsung Galaxy Tab 3, iPad 4), have been evaluated using two procedures: 3D LUT (Look Up Table) and a linear model assuming primary constancy and independence of the channels. The color reproduction errors have been computed with the CIEDE2000 color difference formula. There is good constancy of primaries but large deviations of additivity. The 3D LUT characterization yields smaller reproduction errors and dispersions for the Tab 3 and iPhone 4 devices, but for the iPad 4 and S4, both models are equally good. The smallest reproduction errors occur with both Apple devices, although the iPad 4 has the highest number of outliers of all devices with both colorimetric characterizations. Even though there is good constancy of primaries, the large deviations of additivity exhibited by the devices and the larger reproduction errors make any characterization based on channel independence not recommendable. The smartphone screens show, in average, the best color reproduction performance, particularly the iPhone 4, and therefore, they are more adequate for applications requiring precise color reproduction.

  3. A smartphone colorimetric reader integrated with an ambient light sensor and a 3D printed attachment for on-site detection of zearalenone.

    Science.gov (United States)

    Chen, Yuan; Fu, Qiangqiang; Li, Dagang; Xie, Jun; Ke, Dongxu; Song, Qifang; Tang, Yong; Wang, Hong

    2017-11-01

    Smartphone biosensors could be cost-effective, portable instruments to be used for the readout of liquid colorimetric assays. However, current reported smartphone colorimetric readers have relied on photos of liquid assays captured using a camera, and then analyzed using software programs. This approach results in a relatively low accuracy and low generality. In this work, we reported a novel smartphone colorimetric reader that has been integrated with an ambient light sensor and a 3D printed attachment for the readout of liquid colorimetric assays. The portable and low-cost ($0.15) reader utilized a simplified electronic and light path design. Furthermore, our reported smartphone colorimetric reader can be compatible with different smartphones. As a proof of principle, the utility of this device was demonstrated using it in conjunction with an enzyme-linked immunosorbent assay to detect zearalenone. Results were consistent with those obtained using a professional microplate reader. The developed smartphone colorimetric reader was capable of providing scalable, cost-effective, and accurate results for liquid colorimetric assays that related to clinical diagnoses, environment pollution, and food testing. Graphical abstract A novel smartphone colorimetric reader that has been integrated with an ambient light sensor and a 3D printed attachment for the readout of liquid colorimetric assays.

  4. Impact of Prolonged Blood Incubation and Extended Serum Storage at Room Temperature on the Human Serum Metabolome

    Directory of Open Access Journals (Sweden)

    Beate Kamlage

    2018-01-01

    Full Text Available Metabolomics is a powerful technology with broad applications in life science that, like other -omics approaches, requires high-quality samples to achieve reliable results and ensure reproducibility. Therefore, along with quality assurance, methods to assess sample quality regarding pre-analytical confounders are urgently needed. In this study, we analyzed the response of the human serum metabolome to pre-analytical variations comprising prolonged blood incubation and extended serum storage at room temperature by using gas chromatography-mass spectrometry (GC-MS and liquid chromatography-tandem mass spectrometry (LC-MS/MS -based metabolomics. We found that the prolonged incubation of blood results in a statistically significant 20% increase and 4% decrease of 225 tested serum metabolites. Extended serum storage affected 21% of the analyzed metabolites (14% increased, 7% decreased. Amino acids and nucleobases showed the highest percentage of changed metabolites in both confounding conditions, whereas lipids were remarkably stable. Interestingly, the amounts of taurine and O-phosphoethanolamine, which have both been discussed as biomarkers for various diseases, were 1.8- and 2.9-fold increased after 6 h of blood incubation. Since we found that both are more stable in ethylenediaminetetraacetic acid (EDTA blood, EDTA plasma should be the preferred metabolomics matrix.

  5. Optical diagnosis of dengue virus infection in human blood serum using Raman spectroscopy

    International Nuclear Information System (INIS)

    Saleem, M; Bilal, M; Anwar, S; Rehman, A; Ahmed, M

    2013-01-01

    We present the optical diagnosis of dengue virus infection in human blood serum using Raman spectroscopy. Raman spectra were acquired from 18 blood serum samples using a laser at 532 nm as the excitation source. A multivariate regression model based on partial least-squares regression is developed that uses Raman spectra to predict dengue infection with leave-one-sample-out cross validation. The prediction of dengue infection by our model yields correlation coefficient r 2 values of 0.9998 between the predicted and reference clinical results. The model was tested for six unknown human blood sera and found to be 100% accurate in accordance with the clinical results. (letter)

  6. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles.

    Science.gov (United States)

    Shen, Li; Chen, Jing; Li, Na; He, Pingli; Li, Zhen

    2014-08-11

    A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV-vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL(-1) can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Gold nanoparticles-based colorimetric and visual creatinine assay

    International Nuclear Information System (INIS)

    He, Yi; Zhang, Xianhui; Yu, Haili

    2015-01-01

    We demonstrate a selective and sensitive method for determination of creatinine using citrate-stabilized gold nanoparticles (AuNPs) as a colorimetric probe. It is based on a direct cross-linking reaction that occurs between creatinine and AuNPs that causes aggregation of AuNPs and results in a color change from wine red to blue. The absorption peak is shifted from 520 to 670 nm. Under the optimized conditions, the shift in the absorption peak is related the logarithm of the creatinine concentration in the 0.1 to 20 mM range, and the instrumental detection limit (LOD) is 80 μM. This LOD is about one order of magnitude better than that that of the Jaffé method (720 μM). The assay displays good selectivity over interfering substances including various inorganic ions, organic small compounds, proteins, and biothiols. It was successfully employed to the determination of creatinine in spiked human urine. (author)

  8. Human serum protein and C-reactive protein levels among HIV ...

    African Journals Online (AJOL)

    Human serum protein and C-reactive protein levels were determined among HIV patients visiting St Camillus Hospital, Uromi, Edo State, Nigeria, between January to March, 2013. Fifty (50) HIV patients (20 males; 30 females) and 50 control subjects (24 males; 26 females) were enrolled for this study. The clinical status of ...

  9. Determination of Theophylline Binding to Human Serum Proteins by Isotachophoresis

    NARCIS (Netherlands)

    Reijenga, J.C.; Gaijkema, A.P.M.; Mikkers, F.E.P.

    1984-01-01

    Free theophylline was isolated from human serum by ultrafiltration and analysed in a leading electrolyte of 7.5 mM morpholinoethanesulphoric acid with ammediol as a counter ion at pH 8.90 and -alanine as a terminator. The UV (280 nm) absorbance of the theophylline spike between serine and bicine as

  10. Serum lutein concentrations in healthy term infants fed human milk or infant formula with lutein

    OpenAIRE

    Bettler, Jodi; Zimmer, J. Paul; Neuringer, Martha; DeRusso, Patricia A.

    2009-01-01

    Background Lutein is a carotenoid that may play a role in eye health. Human milk typically contains higher concentrations of lutein than infant formula. Preliminary data suggest there are differences in serum lutein concentrations between breastfed and formula-fed infants. Aim of the study To measure the serum lutein concentrations among infants fed human milk or formulas with and without added lutein. Methods A prospective, double-masked trial was conducted in healthy term formula-fed infant...

  11. Humant serum-albumin som proteinkilde ved dyrkning af humane oocytter, spermatozoer og praeembryoer

    DEFF Research Database (Denmark)

    Andersen, C Y; Hay-Schmidt, Anders; Byskov, A G

    1991-01-01

    patient serum as source of protein in the culture of oocytes, spermatozoa and pre-embryos in IVF-ET treatment. The pregnancy rate per transplantation was increased from 30% in the serum group (21 pregnant out of 69 transplantations) to 39% in the albumin group (26 pregnant out of 66 transplantations...... takes place, also consists of a source of protein. In order to eliminate the variability of patient sera, a prospective, randomized investigation was performed to elucidate whether a well-defined source of protein such as human serum albumin (hSA-hSA 200 mg/ml, Statens Seruminstitute) can replace......SA is recommended as the source of protein, rather than the patient's own serum in the culture of oocytes, spermatozoa and pre-embryos in IVF-ET treatment....

  12. Colorimetric characterization of three wood species from the amazon forest

    Directory of Open Access Journals (Sweden)

    Sâmia Valéria dos Santos Barros

    2014-09-01

    Full Text Available The aim of this study was to analyze wood color variability in the (radial, tangential and transversal anatomic sections of Breu-vermelho, Tauari-vermelho and Pequiarana species through quantitative colorimetry using CIELAB color system. Such species come from a forest sustainable area of Thousand Precious Woods Company, located in Itacoatiara in the Amazon region of Brazil. Five wood samples from each species were selected so as to determine the following colorimetric parameters: L*, a*, b*, C e h*. In addition, 225 measurements were carried out with Konica Minolta CM-5 spectrophotometer connected to the computer. Results pointed out to statistical differences in the colorimetric parameters and also a low saturation in a* in the analyzed species. According to the cluster gathering, Breu-vermelho wood presents olive and/or grayish pink color, Tauari-vermelho is pinkish-gray and Pequiarana is grayish-pink and/or pinkish-gray. Such species presented differences in color among the three anatomic sections cited above and were also influenced by the yellow color defined in b* parameter. To summarize, colorimetric analysis to establish wood color is a simple procedure which may be used from the sawing of the logs until their final exploitation enabling value aggregation to the final product.

  13. Colorimetric Detection of Specific DNA Segments Amplified by Polymerase Chain Reactions

    Science.gov (United States)

    Kemp, David J.; Smith, Donald B.; Foote, Simon J.; Samaras, N.; Peterson, M. Gregory

    1989-04-01

    The polymerase chain reaction (PCR) procedure has many potential applications in mass screening. We describe here a general assay for colorimetric detection of amplified DNA. The target DNA is first amplified by PCR, and then a second set of oligonucleotides, nested between the first two, is incorporated by three or more PCR cycles. These oligonucleotides bear ligands: for example, one can be biotinylated and the other can contain a site for a double-stranded DNA-binding protein. After linkage to an immobilized affinity reagent (such as a cloned DNA-binding protein, which we describe here) and labeling with a second affinity reagent (for example, avidin) linked to horseradish peroxidase, reaction with a chromogenic substrate allows detection of the amplified DNA. This amplified DNA assay (ADA) is rapid, is readily applicable to mass screening, and uses routine equipment. We show here that it can be used to detect human immunodeficiency virus sequences specifically against a background of human DNA.

  14. First-trimester maternal serum human thyroid-stimulating hormone in chromosomally normal and Down syndrome pregnancies

    NARCIS (Netherlands)

    Pratt, JJ; de Wolf, BTHM; Mantingh, A

    Maternal serum human thyroid-stimulating hormone (TSH) levels were investigated in chromosomally normal and Down syndrome pregnancies to determine whether TSH can be used as a marker for Down syndrome in the first trimester. Measurements were conducted on stored serum samples collected from 23 Down

  15. Mechanism of anti-HIV activity of succinylated human serum albumin

    NARCIS (Netherlands)

    Kuipers, ME; Berg, HVD; Swart, PJ; Laman, Jon; Meijer, DKF; Kopelman, MHGM; Huisman, H

    1999-01-01

    In the present study, we described the interaction of succinylated human serum albumin (Suc-HSA), a negatively charged anti-HIV-1 active protein, with HIV-1 gp120 and in detail with the third variable domain of gp120 (V3 loop). To this end, different assay formats were tested in which gp120- and

  16. Surface imprinted beads for the recognition of human serum albumin.

    Science.gov (United States)

    Bonini, Francesca; Piletsky, Sergey; Turner, Anthony P F; Speghini, Adolfo; Bossi, Alessandra

    2007-04-15

    The synthesis of poly-aminophenylboronic acid (ABPA) imprinted beads for the recognition of the protein human serum albumin (HSA) is reported. In order to create homogeneous recognition sites, covalent immobilisation of the template HSA was exploited. The resulting imprinted beads were selective for HSA. The indirect imprinting factor (IF) calculated from supernatant was 1.6 and the direct IF, evaluated from the protein recovered from the beads, was 1.9. The binding capacity was 1.4 mg/g, which is comparable to commercially available affinity materials. The specificity of the HSA recognition was evaluated with competitive experiments, indicating a molar ratio 4.5/1 of competitor was necessary to displace half of the bound HSA. The recognition and binding of the imprinted beads was also tested with a complex sample, human serum and targeted removal of HSA without a loss of the other protein components was demonstrated. The easy preparation protocol of derivatised beads and a good protein recognition properties make the approach an attractive solution to analytical and bio-analytical problems in the field of biotechnology.

  17. Serum total antioxidant capacity in patients with multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Almira Hadžović-Džuvo

    2011-02-01

    Full Text Available Multiple sclerosis (MS is a chronic inflammatory disease of the central nervous system (CNS. It is characterized by loss of myelin, the fatty tissue that surrounds and protects nerve fibres allowing them to conduct electrical impulses. Recent data indicate that oxidative stress (OS plays a major role in the pathogenesis of multiple sclerosis (MS. The aim of this study was to estimate level of serum total antioxidative capacity in patients with multiple sclerosis. Our cross-sectional study included 33 patients with MS and 24 age and sex matched control subjects. All our patients had a Poser criteria for definite diagnostic categories of multiple sclerosis. Serum total antioxidant capacity (TAC was measured by quantitative colorimetric determination, using Total antioxidant Capacity-QuantiCromAntioxidant Assay Kit (BioAssay systems, USA; DTAC-100. Mean serum TAC in multiple sclerosis group of patients was 119.2 mM Trolox equivalents and was significantly lower (p<0.001 compared to the control group of subjects (167.1 mM Trolox equivalents. Our results showed that oxidative stress plays an important role in pathogenesis of multiple sclerosis. This finding, also, suggests the importance of antioxidants in diet and therapy of MS patients.

  18. Development and validation of a colorimetric sensor array for fish spoilage monitoring

    DEFF Research Database (Denmark)

    Morsy, Mohamed K.; Zor, Kinga; Kostesha, Natalie

    2016-01-01

    their color changes in response to compounds present in fresh products (hexanal, 1-octane-3-ol) used as negative controls. The colorimetric sensor array was used to follow fish spoilage over time at room temperature for up to 24 h as well as at 4 °C for 9 days. Additionally, fish decay was monitored using......Given the need for non-destructive methods and sensors for food spoilage monitoring, we have evaluated sixteen chemo-sensitive compounds incorporated in an array for colorimetric detection of typical spoilage compounds (trimethylamine, dimethylamine, cadaverine, putrescine) and characterized...

  19. Colorimetric detection of ammonia using smartphones based on localized surface plasmon resonance of silver nanoparticles.

    Science.gov (United States)

    Amirjani, Amirmostafa; Fatmehsari, Davoud Haghshenas

    2018-01-01

    In this work, a rapid and straightforward method was developed for colorimetric determination of ammonia using smartphones. The mechanisms is based on the manipulation of the surface plasmon band of silver nanoparticles (AgNPs) via the formation of Ag (NH 3 ) 2 + complex. This complex decreases the amount of AgNPs in the solution and consequently, the color intensity of the colloidal system decreases. Not only the variation in color intensity of the solution can be tracked by a UV-vis spectrophotometer, but also a smartphone can be employed to monitor the color intensity variation by RGB analysis. Ammonia, in the concentration range of 10-1000mgL -1 , was successfully measured spectrophotometrically (UV-vis spectrophotometer) and colorimetrically (RGB measurement) with the detection limit of 180 and 200mgL -1 , respectively. Linear relationships were also developed for both methods. Also, the response time of the developed colorimetric sensor was around 20s. Both of the colorimetric and spectrophotometric methods showed a reliable performance for determination of ammonia in the real samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. The cholesterol-lowering effect of coconut flakes in humans with moderately raised serum cholesterol.

    Science.gov (United States)

    Trinidad, Trinidad P; Loyola, Anacleta S; Mallillin, Aida C; Valdez, Divinagracia H; Askali, Faridah C; Castillo, Joan C; Resaba, Rosario L; Masa, Dina B

    2004-01-01

    This study investigated the effect of coconut flakes on serum cholesterol levels of humans with moderately raised serum cholesterol in 21 subjects. The serum total cholesterol of subjects differed and ranged from 259 to 283 mg/dL. The study was conducted in a double-blind randomized crossover design on a 14-week period, consisting of four 2-week experimental periods, with each experimental period separated by a 2-week washout period. The test foods were as follows: corn flakes as the control food, oat bran flakes as the reference food, and corn flakes with 15% and 25% dietary fiber from coconut flakes (made from coconut flour production). Results showed a significant percent reduction in serum total and low-density lipoprotein (LDL) cholesterol (in mg/dL) for all test foods, except for corn flakes, as follows: oat bran flakes, 8.4 +/- 1.4 and 8.8 +/- 6.0, respectively; 15% coconut flakes, 6.9 +/- 1.1 and 11.0 +/- 4.0, respectively; and 25% coconut flakes, 10.8 +/- 1.3 and 9.2 +/- 5.4, respectively. Serum triglycerides were significantly reduced for all test foods: corn flakes, 14.5 +/- 6.3%; oat bran flakes, 22.7 +/- 2.9%; 15% coconut flakes, 19.3 +/- 5.7%; and 25% coconut flakes, 21.8 +/- 6.0%. Only 60% of the subjects were considered for serum triglycerides reduction (serum triglycerides >170 mg/dL). In conclusion, both 15% and 25% coconut flakes reduced serum total and LDL cholesterol and serum triglycerides of humans with moderately raised serum cholesterol levels. Coconut flour is a good source of both soluble and insoluble dietary fiber, and both types of fiber may have significant role in the reduction of the above lipid biomarker. To our knowledge, this is the first study conducted to show a relationship between dietary fiber from a coconut by-product and a lipid biomarker. Results from this study serves as a good basis in the development of coconut flakes/flour as a functional food, justifying the increased production of coconut and coconut by-products.

  1. Alteration of human serum albumin binding properties induced by modifications: A review

    Science.gov (United States)

    Maciążek-Jurczyk, Małgorzata; Szkudlarek, Agnieszka; Chudzik, Mariola; Pożycka, Jadwiga; Sułkowska, Anna

    2018-01-01

    Albumin, a major transporting protein in the blood, is the main target of modification that affects the binding of drugs to Sudlow's site I and II. These modification of serum protein moderates its physiological function, and works as a biomarker of some diseases. The main goal of the paper was to explain the possible alteration of human serum albumin binding properties induced by modifications such as glycation, oxidation and ageing, their origin, methods of evaluation and positive and negative meaning described by significant researchers.

  2. Cost Effective Paper-Based Colorimetric Microfluidic Devices and Mobile Phone Camera Readers for the Classroom

    Science.gov (United States)

    Koesdjojo, Myra T.; Pengpumkiat, Sumate; Wu, Yuanyuan; Boonloed, Anukul; Huynh, Daniel; Remcho, Thomas P.; Remcho, Vincent T.

    2015-01-01

    We have developed a simple and direct method to fabricate paper-based microfluidic devices that can be used for a wide range of colorimetric assay applications. With these devices, assays can be performed within minutes to allow for quantitative colorimetric analysis by use of a widely accessible iPhone camera and an RGB color reader application…

  3. The reference range of serum, plasma and erythrocyte magnesium

    Directory of Open Access Journals (Sweden)

    Suzanna Immanuel

    2006-12-01

    Full Text Available The interest in the clinical importance of serum magnesium level has just recently begun with the analysis and findings of abnormal magnesium level in cardiovascular, metabolic and neuromuscular disorder. Although the serum level does not reflect the body magnesium level, but currently, only serum magnesium determination is widely used. Erythrocyte magnesium is considered more sensitive than serum magnesium as it reflects intracellular magnesium status. According to NCCLS (National Committee for Clinical Laboratory Standards every laboratory is recommended to have its own reference range for the tests it performs, including magnesium determination. The reference range obtained is appropriate for the population and affected by the method and technique. This study aimed to find the reference range of serum and plasma magnesium and also intracellular magnesium i.e. erythrocyte magnesium by direct method, and compare the results of serum and plasma magnesium. Blood was taken from 114-blood donor from Unit Transfusi Darah Daerah (UTDD Budhyarto Palang Merah Indonesia (PMI DKI Jakarta, consisted of 57 male and 57 female, aged 17 – 65 years, clinically healthy according to PMI donor criteria. Blood was taken from blood set, collected into 4 ml vacuum tube without anticoagulant for serum magnesium determination and 3 ml vacuum tube with lithium heparin for determination of erythrocyte and plasma magnesium Determination of magnesium level was performed with clinical chemistry auto analyzer Hitachi 912 by Xylidil Blue method colorimetrically. This study showed no significant difference between serum and heparinized plasma extra cellular magnesium. The reference range for serum or plasma magnesium was 1.30 – 2.00 mEq/L and for erythrocyte magnesium was 4.46 - 7.10 mEq/L. (Med J Indones 2006; 15:229-35Keywords: Reference range, extracellular magnesium, intracellular magnesium

  4. Use of mep HyperCel for polishing of human serum albumin.

    Science.gov (United States)

    McCann, Karl B; Vucica, Yvonne; Wu, John; Bertolini, Joseph

    2014-10-15

    The manufacture of human serum albumin by chromatographic procedures involves gel filtration chromatography as a final polishing step. Despite this step being essential to remove high molecular weight impurity proteins and thus ensure a stable and safe final product, it is relatively inefficient. This paper explores the use of hydrophobic charge induction chromatographic media, MEP HyperCel as an alternative to Sephacryl S200HR gel filtration for the polishing of human serum albumin derived by ion exchange chromatographic purification of Cohn Supernatant I. The use of MEP HyperCel results in a product with a higher purity than achieved with gel filtration and in a less time consuming manner and with potential resource savings. MEP HyperCel appears to have great potential for incorporation into downstream processes in the plasma fractionation industry as an efficient means of achieving polishing of intermediates or capture of proteins of interest. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Dual-Modal Colorimetric/Fluorescence Molecular Probe for Ratiometric Sensing of pH and Its Application.

    Science.gov (United States)

    Wu, Luling; Li, Xiaolin; Huang, Chusen; Jia, Nengqin

    2016-08-16

    As traditional pH meters cannot work well for minute regions (such as subcellular organelles) and in harsh media, molecular pH-sensitive devices for monitoring pH changes in diverse local heterogeneous environments are urgently needed. Here, we report a new dual-modal colorimetric/fluorescence merocyanine-based molecular probe (CPH) for ratiometric sensing of pH. Compared with previously reported pH probes, CPH bearing the benzyl group at the nitrogen position of the indolium group and the phenol, which is used as the acceptor for proton, could respond to pH changes immediately through both the ratiometric fluorescence signal readout and naked-eye colorimetric observation. The sensing process was highly stable and reversible. Most importantly, the suitable pKa value (6.44) allows CPH to presumably accumulate in lysosomes and become a lysosome-target fluorescent probe. By using CPH, the intralysosomal pH fluctuation stimulated by antimalaria drug chloroquine was successfully tracked in live cells through the ratiometric fluorescence images. Additionally, CPH could be immobilized on test papers, which exhibited a rapid and reversible colorimetric response to acid/base vapor through the naked-eye colorimetric analysis. This proof-of-concept study presents the potential application of CPH as a molecular tool for monitoring intralysosomal pH fluctuation in live cells, as well as paves the way for developing the economic, reusable, and fast-response optical pH meters for colorimetric sensing acid/base vapor with direct naked-eye observation.

  6. A comparative study of some physico-chemical properties of human serum albumin samples from different sources--I : Some physico-chemical properties of isoionic human serum albumin solutions

    NARCIS (Netherlands)

    Dröge, J.H.M.; Janssen, L.H.M.; Wilting, J.

    1982-01-01

    Human serum albumin samples from different sources were investigated. The fatty acid content of the albumin before and after deionization on a mixed bed ion-exchange column varied from sample to sample. When an albumin sample from one source was deionized under standard conditions the amount of

  7. Human adipose stromal cells expanded in human serum promote engraftment of human peripheral blood hematopoietic stem cells in NOD/SCID mice

    International Nuclear Information System (INIS)

    Kim, Su Jin; Cho, Hyun Hwa; Kim, Yeon Jeong; Seo, Su Yeong; Kim, Han Na; Lee, Jae Bong; Kim, Jae Ho; Chung, Joo Seop; Jung, Jin Sup

    2005-01-01

    Human mesenchymal stem cells (hMSC), that have been reported to be present in bone marrow, adipose tissues, dermis, muscles, and peripheral blood, have the potential to differentiate along different lineages including those forming bone, cartilage, fat, muscle, and neuron. Therefore, hMSC are attractive candidates for cell and gene therapy. The optimal conditions for hMSC expansion require medium supplemented with fetal bovine serum (FBS). Some forms of cell therapy will involve multiple doses, raising a concern over immunological reactions caused by medium-derived FBS proteins. In this study, we cultured human adipose stromal cells (hADSC) and bone marrow stroma cells (HBMSC) in human serum (HS) during their isolation and expansion, and demonstrated that they maintain their proliferative capacity and ability for multilineage differentiation and promote engraftment of peripheral blood-derived CD34(+) cells mobilized from bone marrow in NOD/SCID mice. Our results indicate that hADSC and hBMSC cultured in HS can be used for clinical trials of cell and gene therapies, including promotion of engraftment after allogeneic HSC transplantation

  8. Protein Turnover Measurements in Human Serum by Serial Immunoaffinity LC-MS/MS.

    Science.gov (United States)

    Farrokhi, Vahid; Chen, Xiaoying; Neubert, Hendrik

    2018-02-01

    The half-life of target proteins is frequently an important parameter in mechanistic pharmacokinetic and pharmacodynamic (PK/PD) modeling of biotherapeutics. Clinical studies for accurate measurement of physiologically relevant protein turnover can reduce the uncertainty in PK/PD model-based predictions, for example, of the therapeutic dose and dosing regimen in first-in-human clinical trials. We used a targeted mass spectrometry work flow based on serial immunoaffinity enrichment ofmultiple human serum proteins from a [5,5,5- 2 H 3 ]-L-leucine tracer pulse-chase study in healthy volunteers. To confirm the reproducibility of turnover measurements from serial immunoaffinity enrichment, multiple aliquots from the same sample set were subjected to protein turnover analysis in varying order. Tracer incorporation was measured by multiple-reaction-monitoring mass spectrometry and target turnover was calculated using a four-compartment pharmacokinetic model. Five proteins of clinical or therapeutic relevance including soluble tumor necrosis factor receptor superfamily member 12A, tissue factor pathway inhibitor, soluble interleukin 1 receptor like 1, soluble mucosal addressin cell adhesion molecule 1, and muscle-specific creatine kinase were sequentially subjected to turnover analysis from the same human serum sample. Calculated half-lives ranged from 5-15 h; however, no tracer incorporation was observed for mucosal addressin cell adhesion molecule 1. The utility of clinical pulse-chase studies to investigate protein turnover can be extended by serial immunoaffinity enrichment of target proteins. Turnover analysis from serum and subsequently from remaining supernatants provided analytical sensitivity and reproducibility for multiple human target proteins in the same sample set, irrespective of the order of analysis. © 2017 American Association for Clinical Chemistry.

  9. Colorimetric and sensory characteristics of fermented cured sausage with Brazilian ostrich meat addition

    Directory of Open Access Journals (Sweden)

    Carlos Pasqualin Cavalheiro

    2013-12-01

    Full Text Available The aim of this study was to determine the colorimetric and sensory characteristics of a fermented cured sausage containing ostrich meat (Struthio camelus and pork meat. Four treatments were performed: one with no ostrich meat (TC and the others containing 19.08 (T1, 38.34 (T2, and 57.60% (T3 of ostrich meat and pork meat. Colorimetric analyses were measuring L*, a*, b*, C*, and hº. Sensory analysis was conducted assessing color, aroma, flavor, and texture at the end of the sausages' processing. The sausages containing ostrich meat were statistically different from the control in the instrumental colorimetric analysis. In the sensory analysis, no significant differences were observed between the treatments for aroma, flavor, and texture. However, significant differences were found in the color of the sausages due to the high myoglobin content present in the ostrich meat, which resulted in a very dark color in the treatment with the highest percentage of this type of meat.

  10. Electrospun fibre colorimetric probe based on gold nanoparticles for ...

    African Journals Online (AJOL)

    2014-11-20

    Nov 20, 2014 ... pump operated at a flow rate of 0.300 mℓ/h and a high-voltage power supply with a ..... Y (2012) A simple colorimetric sensor based on anti-aggregation of ... inside polystyrene domains dispersed in an epoxy matrix. Eur.

  11. Biomonitoring of selenoprotein P in human serum by fast affinity chromatography coupled to ICP-MS.

    Science.gov (United States)

    Heitland, Peter; Köster, Helmut D

    2018-04-01

    Most of the Se in human serum is bound to selenoprotein P (SEPP1) in which Se is present in form of selenocysteine. The SEPP1 is a new possible biomarker for the Se status and for this reason we developed a fast, simple and reliable method for the quantitative determination of SEPP1 in serum by affinity chromatography coupled to ICP-MS. It is possible to separate SEPP1 from other selenoproteins in serum in only 5 min, which allows high sample throughput in clinical laboratories. Measured and certified concentrations of total Se and Se(SEPP1) are in good agreement for the reference material SRM 1950. The SEPP1 concentration was stable in serum samples of 3 persons for a minimum of 2 weeks. Further results of method validation were described including internal and external quality assurance. The analytical method was applied for a biomonitoring study of the SEPP1 and total Se concentration in human serum of 50 occupationally non-exposed persons living in northern Germany. Concentration ranges and mean concentrations for Se(SEPP1) are 31.1-59.7 and 46.2 μg/L, respectively. The corresponding values for total Se are 62-120 and 83.5 μg/L. The mean percentage of total Se in serum present as SEPP1 is 58%. Copyright © 2018 Elsevier GmbH. All rights reserved.

  12. Serum-Sphingosine-1-Phosphate Concentrations Are Inversely Associated with Atherosclerotic Diseases in Humans.

    Directory of Open Access Journals (Sweden)

    Irina Soltau

    Full Text Available Atherosclerotic changes of arteries are the leading cause for deaths in cardiovascular disease and greatly impair patient's quality of life. Sphingosine-1-phosphate (S1P is a signaling sphingolipid that regulates potentially pro-as well as anti-atherogenic processes. Here, we investigate whether serum-S1P concentrations are associated with peripheral artery disease (PAD and carotid stenosis (CS.Serum was sampled from blood donors (controls, N = 174 and from atherosclerotic patients (N = 132 who presented to the hospital with either clinically relevant PAD (N = 102 or CS (N = 30. From all subjects, serum-S1P was measured by mass spectrometry and blood parameters were determined by routine laboratory assays. When compared to controls, atherosclerotic patients before invasive treatment to restore blood flow showed significantly lower serum-S1P levels. This difference cannot be explained by risk factors for atherosclerosis (old age, male gender, hypertension, hypercholesteremia, obesity, diabetes or smoking or comorbidities (Chronic obstructive pulmonary disease, kidney insufficiency or arrhythmia. Receiver operating characteristic curves suggest that S1P has more power to indicate atherosclerosis (PAD and CS than high density lipoprotein-cholesterol (HDL-C. In 35 patients, serum-S1P was measured again between one and six months after treatment. In this group, serum-S1P concentrations rose after treatment independent of whether patients had PAD or CS, or whether they underwent open or endovascular surgery. Post-treatment S1P levels were highly associated to platelet numbers measured pre-treatment.Our study shows that PAD and CS in humans is associated with decreased serum-S1P concentrations and that S1P may possess higher accuracy to indicate these diseases than HDL-C.

  13. A radioimmunoassay for erythropoietin: serum levels in normal human subjects and patients with hemopoietic disorders

    International Nuclear Information System (INIS)

    Rege, A.B.; Brookins, J.; Fisher, J.W.

    1982-01-01

    An RIA for Ep has been developed that is highly sensitive and specific. A homogeneous Ep preparation was labeled with 125 I by the chloramine-T method to a specific activity of 90 to 136 micro Ci/microgram and immunoreactivity of 80%. Ep antiserum, which was produced to a human urinary Ep preparation (80 U/mg of protein), was adsorbed with normal human urinary and serum proteins without any loss in sensitivity of the RIA to increase the specificity of the assay. A good correlation was seen between the RIA and the exhypoxic polycythemic mouse assay (corr. coef. 0.967; slope 1.05 and y intercept 0.75). Ep titers in sera from 175 hematologically normal human subjects exhibited a normal frequency distribution and ranged between 5.8 and 36.6 mU/ml with a mean of 14.9 +/- 4.7 (S.D.) and median of 14.3 Serum Ep titers were markedly elevated in seven patients with aplastic anemia and one patient with pure red cell aplasia (1350 to 20,640 mU/ml) and were lower than normal in two patients with polycythemia vera (8.1 and 9.4 mU/ml). The serum Ep titers in a prenephrectomy patient with chronic glomerulonephritis (32.1 mU/ml) decreased to below normal levels (9.04 mU/ml) after nephrectomy. The cord serum erythropoietin titers in 10 IDM [90.82 +/- 134.1 (S.D.) mu/ml] returned to values within the normal range (13.86 +/- 5.55) on day 3 after birth, suggesting the utility of the RIA in elucidating the role of hypoxia and/or insulin in increased erythropoiesis in IDM. The serum Ep titers in patients with anemias and polycythemias were compared to those of normal human subjects and agreed well with pathophysiologic mechanisms of these hemopoietic disorders, confirming the validity of the RIA

  14. A radioimmunoassay for erythropoietin: serum levels in normal human subjects and patients with hemopoietic disorders

    International Nuclear Information System (INIS)

    Rege, A.B.; Brookins, J.; Fisher, J.W.

    1982-01-01

    An RIA for Ep has been developed that is highly sensitive and specific. A homogeneous Ep preparation was labeled with 125 I by the chloramine-T method to a specific activity of 90 to 136 μCi/μg and immunoreactivity of 80%. Ep antiserum, which was produced to a human urinary Ep preparation (80 U/mg of protein), was adsorbed with normal human urinary and serum proteins without any loss in sensitivity of the RIA to increase the specificity of the assay. A good correlation was seen between the RIA and the exhypoxic polycythemic mouse assay (corr. coef. 0.967; slope 1.05 and ''y'' intercept 0.75). Ep titers in sera from 175 hematologically normal human subjects exhibited a normal frequency distribution and ranged between 5.8 and 36.6 mU/ml with a mean of 14.9 +/- 4.7 (S.D.) and median of 14.3. Serum Ep titers were markedly elevated in seven patients with aplastic anemia and one patient with pure red cell aplasia (1350 to 20,640 mU/ml) and were lower than normal in two patients with polycythemia vera (8.1 and 9.4 mU/ml). The serum Ep titers in a prenephrectomy patient with chronic glomerulonephritis (31.1 mU/ml) decreased to below normal levels (9.04 mU/ml) after nephrectomy. The cord serum erythropoietin titers in 10 IDM [90.82 +/- 134.1 (S.D.) mu/ml] returned to values within the normal range (13.86 +/- 5.55) on day 3 after birth, suggesting the utility of the RIA in elucidating the role of hypoxia and/or insulin in increased erythropoiesis in IDM. The serum Ep titers in patients with anemias and polycythemias were compared to those of normal human subjects and agreed well with pathophysiologic mechanisms of these hemopoietic disorders, confirming the validity of the RIA

  15. Milk and serum standard reference materials for monitoring organic contaminants in human samples.

    Science.gov (United States)

    Schantz, Michele M; Eppe, Gauthier; Focant, Jean-François; Hamilton, Coreen; Heckert, N Alan; Heltsley, Rebecca M; Hoover, Dale; Keller, Jennifer M; Leigh, Stefan D; Patterson, Donald G; Pintar, Adam L; Sharpless, Katherine E; Sjödin, Andreas; Turner, Wayman E; Vander Pol, Stacy S; Wise, Stephen A

    2013-02-01

    Four new Standard Reference Materials (SRMs) have been developed to assist in the quality assurance of chemical contaminant measurements required for human biomonitoring studies, SRM 1953 Organic Contaminants in Non-Fortified Human Milk, SRM 1954 Organic Contaminants in Fortified Human Milk, SRM 1957 Organic Contaminants in Non-Fortified Human Serum, and SRM 1958 Organic Contaminants in Fortified Human Serum. These materials were developed as part of a collaboration between the National Institute of Standards and Technology (NIST) and the Centers for Disease Control and Prevention (CDC) with both agencies contributing data used in the certification of mass fraction values for a wide range of organic contaminants including polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, polybrominated diphenyl ether (PBDE) congeners, and polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners. The certified mass fractions of the organic contaminants in unfortified samples, SRM 1953 and SRM 1957, ranged from 12 ng/kg to 2200 ng/kg with the exception of 4,4'-DDE in SRM 1953 at 7400 ng/kg with expanded uncertainties generally <14 %. This agreement suggests that there were no significant biases existing among the multiple methods used for analysis.

  16. Establishment and clinical application of immunoradiometric assay for human growth hormone in serum

    International Nuclear Information System (INIS)

    Ji Jinfeng; Wu Congyuan; Niu Zhanpo; Zhang Kui; Song Ailing; Deng Jieying; Shi Mifan

    1992-01-01

    An immunoradiometric assay (IRMA) for human growth hormone (hGH) in serum is developed based on two high specific monoclonal antibodies against hGh. It can specifically detect the levels of serum bioactive hGh and had no cross-reaction with human prolactin (hPRL) and hGh oligmeric forms. The sensitivity was 0.2 ng/ml and the recovery for different concentrations of hGh was 92.0% ∼ 103.2%. The coefficients of variation for intra and inter-assay were<9.1% and <14.2%, respectively. Integral analysis of the results of RIA and IRMA with the patients' clinical manifestations revealed that hGh IRMA is better than hGh RIA in reflecting the clinical states of different acromegalic patients

  17. Carbon nanotubes-assisted polyacrylamide gel electrophoresis for enhanced separation of human serum proteins and application in liverish diagnosis.

    Science.gov (United States)

    Jiang, Fubin; Wang, Yanan; Hu, Xinfang; Shao, Na; Na, Na; Delanghe, Joris R; Ouyang, Jin

    2010-11-01

    The application of pore-gradient polyacrylamide gel electrophoresis (PG-PAGE) incorporated with carbon nanotube modified by Triton X-100 and carboxylation so as to improve the separation of human serum proteins is reported. The novel PG-PAGE was made by adding water-soluble single-walled carbon nanotubes (CNTs) when preparing the polyacrylamide gel. Significant improvements in separation of complement C3 protein and haptoglobin (Hp) in human serum were achieved. It was estimated that the interactions between the hydrophilic groups on the proteins and the surface of the CNTs result in different adsorption kinetics of complement C3 and Hp subtype on the nanoparticles incorporated in the gel, thus enhancing the separation of the two proteins in serum. This new CNT matrix-assisted PG-PAGE method for enhanced separation of complement C3 and Hp in human serum was successfully applied to distinguish the samples from liverish patients and healthy people.

  18. A simple and selective colorimetric mercury (II) sensing system based on chitosan stabilized gold nanoparticles and 2,6-pyridinedicarboxylic acid

    International Nuclear Information System (INIS)

    Tian, Kun; Siegel, Gene; Tiwari, Ashutosh

    2017-01-01

    The development of simple and cost-effective methods for the detection and treatment of Hg 2+ in the environment is an important area of research due to the serious health risk that Hg 2+ poses to humans. Colorimetric sensing based on the induced aggregation of nanoparticles is of great interest since it offers a low cost, simple, and relatively rapid procedure, making it perfect for on-site analysis. Herein we report the development of a simple colorimetric sensor for the selective detection and estimation of mercury ions in water, based on chitosan stabilized gold nanoparticles (AuNPs) and 2,6-pyridinedicarboxylic acid (PDA). In the presence of Hg 2+ , PDA induces the aggregation of AuNPs, causing the solution to change colors varying from red to blue, depending on the concentration of Hg 2+ . The formation of aggregated AuNPs in the presence of Hg 2+ was confirmed using transmission electron microscopy (TEM) and UV–Vis spectroscopy. The method exhibits linearity in the range of 300 nM to 5 μM and shows excellent selectivity towards Hg 2+ among seventeen different metal ions and was successfully applied for the detection of Hg 2+ in spiked river water samples. The developed technique is simple and superior to the existing techniques in that it allows detection of Hg 2+ using the naked eye and simple and rapid colorimetric analysis, which eliminates the need for sophisticated instruments and sample preparation methods. - Highlights: • A simple colorimetric method for detection of Hg 2+ in water was proposed. • Au nanoparticles and 2,6-pyridinedicarboxylic acid were used for sensing Hg 2+ . • Sensing mechanisms were demonstrated by TEM and UV–Visible measurements. • It showed the solution color changes from red to blue upon addition of Hg 2+ . • The method selectively detected Hg 2+ among seventeen different metal ions.

  19. Passive Leak Detection Using Commercial Hydrogen Colorimetric Indicator

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Kevin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Buttner, William [National Renewable Energy Lab. (NREL), Golden, CO (United States); Burgess, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Rivkin, Carl [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    Element One, Inc. (www.elem.com), a small business with in Boulder, CO, has been developing hydrogen detection technology based upon a highly selective colorimetric indicator. In its native state, the indicator pigment is a pale gray color, but becomes black upon exposure to hydrogen. The colorimetric change can be readily observed by the naked eye without the need for supplemental electronics or other hardware. Recently, the colorimetric indicator was integrated into a pliable, self-adhesive tape that can readily wrap around pneumatic fittings to serve as a hydrogen leak detector. A prototype version of the Element One indicator tape was tested within an NREL hydrogen system and successfully identified the unexpected presence of a small leak; a summary document for this case study is presented in Appendix 1. The tape was subsequently configured into 10-foot rolls as a product prototype that has just recently been commercialized and marketed under the tradename DetecTape(R). Figure 1 shows the commercial version of DetecTape along with an indicator sample in its native state and one that had been exposed to hydrogen. DetecTape is a self-adhesive silicone-based tape impregnated with a proprietary hydrogen-sensitive indicator based on transition metal oxides. A length of the tape can be cut from the roll and stretched by a factor of two or three times around a fitting. Due to the self-adhesive property of the tape, this provides a tight seal around the fitting. The seal is not hermetic, and is not intended to prevent the release of a leaking gas. However, a portion of the hydrogen leaking from a wrapped fitting will pass through the tape and react with the active indicator impregnated within the tape, thereby inducing blackening.

  20. A colorimetric tetrathiafulvalene-calix 4 pyrrole anion sensor

    DEFF Research Database (Denmark)

    Nielsen, K. A.

    2012-01-01

    The interaction and colorimetric sensing properties of a tetrathiafulvalene substituted calix[4]pyrrole sensor with anions were investigated using H-1 NMR and absorption spectroscopic techniques. Visual color changes were observed upon addition of different anions (Cl-, Br-, CN-, and Ac......O-) to a solution of the sensor. (C) 2012 Elsevier Ltd. All rights reserved....

  1. Relationship between colorimetric (instrumental) evaluation and consumer-defined beef colour acceptability.

    Science.gov (United States)

    Holman, Benjamin W B; Mao, Yanwei; Coombs, Cassius E O; van de Ven, Remy J; Hopkins, David L

    2016-11-01

    The relationship between instrumental colorimetric values (L*, a*, b*, the ratio of reflectance at 630nm and 580nm) and consumer perception of acceptable beef colour was evaluated using a web-based survey and standardised photographs of beef m. longissimus lumborum with known colorimetrics. Only L* and b* were found to relate to average consumer opinions of beef colour acceptability. Respondent nationality was also identified as a source of variation in beef colour acceptability score. Although this is a preliminary study with the findings necessitating additional investigation, these results suggest L* and b* as candidates for developing instrumental thresholds for consumer beef colour expectations. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  2. Deposition of cellular fibronectin and desorption of human serum albumin during adhesion and spreading of human endothelial cells on polymers

    NARCIS (Netherlands)

    Dekker, A.; Dekker, A.; Beugeling, T.; Beugeling, T.; Wind, H.; Poot, Andreas A.; Bantjes, A.; Bantjes, A.; Feijen, Jan; van Aken, W.G.

    1991-01-01

    More insight into the mechanism of adhesion of human endothelial cells (HEC) on to polymeric surfaces may lead to the development of improved small-diameter vascular grafts. HEC suspended in 20% human serum-containing culture medium adhere and spread well on moderately water-wettable polymers such

  3. Application of Chemometric Techniques to Colorimetric Data in Classifying Automobile Paint

    International Nuclear Information System (INIS)

    Nur Awatif Rosli; Rozita Osman; Norashikin Saim; Mohd Zuli Jaafar

    2015-01-01

    The analysis of paint chips is of great interest to forensic investigators, particularly in the examination of hit-and run cases. This study proposes a direct and rapid method in classifying automobile paint samples based on colorimetric data sets; absorption value, reflectance value, luminosity value (L), degree of redness (a) and degree of yellowness (b) obtained from video spectral comparator (VSC) technique. A total of 42 automobile paint samples from 7 manufacturers were analysed. The colorimetric datasets obtained from VSC analysis were subjected to chemometric technique namely cluster analysis (CA) and principal component analysis (PCA). Based on CA, 5 clusters were generated; Cluster 1 consisted of silver color, cluster 2 consisted of white color, cluster 3 consisted of blue and black colors, cluster 4 consisted of red color and cluster 5 consisted of light blue color. PCA resulted in two latent factors explaining 95.58 % of the total variance, enabled to group the 42 automobile paints into five groups. Chemometric application on colorimetric datasets provide meaningful classification of automobile paints based on their tone colour (L, a, b) and light intensity These approaches have the potential to ease the interpretation of complex spectral data involving a large number of comparisons. (author)

  4. A highly sensitive and selective aptamer-based colorimetric sensor for the rapid detection of PCB 77.

    Science.gov (United States)

    Cheng, Ruojie; Liu, Siyao; Shi, Huijie; Zhao, Guohua

    2018-01-05

    A highly sensitive, specific and simple colorimetric sensor based on aptamer was established for the detection of polychlorinated biphenyls (PCB 77). The use of unmodified gold nanoparticles as a colorimetric probe for aptamer sensors enabled the highly sensitive and selective detection of polychlorinated biphenyls (PCB 77). A linear range of 0.5nM to 900nM was obtained for the colorimetric assay with a minimum detection limit of 0.05nM. In addition, by the methods of circular dichroism, UV and naked eyes, we found that the 35 base fragments retained after cutting 5 bases from the 5 'end of aptamer plays the most significant role in the PCB 77 specific recognition process. We found a novel way to truncated nucleotides to optimize the detection of PCB 77, and the selected nucleotides also could achieve high affinity with PCB 77. At the same time, the efficient detection of the PCB 77 by our colorimetric sensor in the complex environmental water samples was realized, which shows a good application prospect. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Fluorescent and Colorimetric Electrospun Nanofibers for Heavy-Metal Sensing

    Directory of Open Access Journals (Sweden)

    Idelma A. A. Terra

    2017-12-01

    Full Text Available The accumulation of heavy metals in the human body and/or in the environment can be highly deleterious for mankind, and currently, considerable efforts have been made to develop reliable and sensitive techniques for their detection. Among the detection methods, chemical sensors appear as a promising technology, with emphasis on systems employing optically active nanofibers. Such nanofibers can be obtained by the electrospinning technique, and further functionalized with optically active chromophores such as dyes, conjugated polymers, carbon-based nanomaterials and nanoparticles, in order to produce fluorescent and colorimetric nanofibers. In this review we survey recent investigations reporting the use of optically active electrospun nanofibers in sensors aiming at the specific detection of heavy metals using colorimetry and fluorescence methods. The examples given in this review article provide sufficient evidence of the potential of optically electrospun nanofibers as a valid approach to fabricate highly selective and sensitive optical sensors for fast and low-cost detection of heavy metals.

  6. Human CRISP-3 binds serum alpha(1)B-glycoprotein across species

    DEFF Research Database (Denmark)

    Udby, Lene; Johnsen, Anders H; Borregaard, Niels

    2010-01-01

    CRISP-3 was previously shown to be bound to alpha(1)B-glycoprotein (A1BG) in human serum/plasma. All mammalian sera are supposed to contain A1BG, although its presence in rodent sera is not well-documented. Since animal sera are often used to supplement buffers in experiments, in particular...

  7. Reversible covalent binding of neratinib to human serum albumin in vitro.

    Science.gov (United States)

    Chandrasekaran, Appavu; Shen, Li; Lockhead, Susan; Oganesian, Aram; Wang, Jianyao; Scatina, JoAnn

    2010-12-01

    Neratinib (HKI-272), an irreversible inhibitor of Her 2 tyrosine kinase, is currently in development as an alternative for first and second line therapy in metastatic breast cancer patients who overexpress Her 2. Following incubation of [(14)C]neratinib in control human plasma at 37°C for 6 hours, about 60% to 70% of the radioactivity was not extractable, due to covalent binding to albumin. In this study, factors that could potentially affect the covalent binding of neratinib to plasma proteins, specifically to albumin were investigated. When [(14)C]neratinib was incubated at 10 μg/mL in human serum albumin (HSA) or control human plasma, the percent binding increased with time; the highest percentages of binding (46 and 67%, respectively) were observed at 6 hours, the longest duration of incubation examined. Binding increased with increasing temperature; the highest percentages of binding to HSA or human plasma (59 and 78%) were observed at 45°C, the highest temperature tested. The binding also increased with increasing pH of incubation; the highest percentages of binding (56 and 65%) were observed at pH 8.5, the highest pH value tested. The percentages of binding were similar (53% to 57%) when a wide range of concentrations of [(14)C]neratinib (50 ng/mL to 10 μg/mL) were incubated with human plasma at 37°C for 6 hours, indicating that the binding was independent of the substrate concentration, especially in the therapeutic range (50 to 200 ng/mL). When human plasma proteins containing covalently bound [(14)C]neratinb were suspended in a 10 fold volume of phosphate buffer at pH 4.0, 6.0, 7.4, and 8.5, and further incubated at 37°C for ~ 16 hours, about 45%, 44%, 32%, and 12% of the total radioactivity, respectively, was released as unchanged [(14)C]neratinib, indicating that the binding is reversible in nature, with more released at pH 7.4 and below. In conclusion, the covalent binding of neratinib to serum albumin is pH, time and temperature dependent, but

  8. Determination of ribavirin in human serum using liquid chromatography tandem mass spectrometry

    NARCIS (Netherlands)

    van der Lijke, H.; Alffenaar, J.-W. C.; Kok, W.Th.; Greijdanus, B.; Uges, D.R.A.

    2012-01-01

    A method has been developed for the determination of ribavirin in human serum for therapeutic drug monitoring purposes, using liquid chromatography electrospray ionization mass spectrometry. Separation was obtained with a mobile phase gradient starting and ending in 100% aqueous conditions using a

  9. Levels of dechloranes and polybrominated diphenyl ethers (PBDEs) in human serum from France.

    Science.gov (United States)

    Brasseur, Catherine; Pirard, Catherine; Scholl, Georges; De Pauw, Edwin; Viel, Jean-François; Shen, Li; Reiner, Eric J; Focant, Jean-François

    2014-04-01

    Human exposure to dechloranes has been evaluated in Western Europe (France) with the analysis of Dechlorane Plus (DP), Dechloranes (Dec) 602, 603 and 604, Chlordene Plus (CP) and Mirex in 48 serum samples collected between 2003 and 2005. While no production source has been identified in Europe until now, detection frequencies for all investigated dechloranes were high, except for Dec 604 which was below detection limit for all samples. The mean DP concentration was 1.40±1.40ng/g lipid weight (lw), lower than levels reported in serum from Chinese population, but higher than levels reported in Canadian human milk. To the best of our knowledge, this is the first time that ∑5dechlorane levels are reported for human serum. A specific pattern of contamination was found (Dec 603>DP>Mirex>Dec 602>CP) compared to other biota samples that have been analyzed from Europe, with Dec 603 as the most abundant dechlorane (mean level: 2.61±2.63ng/g lw). Dec 603 and CP levels were correlated with age and with levels of some bioaccumulative organochlorine pesticides (OCPs). These results indicate that bioaccumulation properties should be further investigated and taken in consideration when assessing human exposure to dechloranes. For comparison purposes, polybrominated diphenyl ether (PBDE) levels were also measured for BDE-47, -99, -100, -153 and -154 in the serum samples. As expected, BDE-47 and BDE-153 were the major congeners with mean levels of 2.06±1.80ng/g lw and 1.39±0.97ng/g lw, respectively. The mean ∑5PBDE levels (4.32±2.99ng/g lw) were in the range typical of Western Europe levels, but lower than the mean ∑5dechlorane levels (6.24±4.16ng/g lw). These results indicate that the attention to dechloranes should be continued if research indicates toxicological concerns. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Detection of proteins using a colorimetric bio-barcode assay.

    Science.gov (United States)

    Nam, Jwa-Min; Jang, Kyung-Jin; Groves, Jay T

    2007-01-01

    The colorimetric bio-barcode assay is a red-to-blue color change-based protein detection method with ultrahigh sensitivity. This assay is based on both the bio-barcode amplification method that allows for detecting miniscule amount of targets with attomolar sensitivity and gold nanoparticle-based colorimetric DNA detection method that allows for a simple and straightforward detection of biomolecules of interest (here we detect interleukin-2, an important biomarker (cytokine) for many immunodeficiency-related diseases and cancers). The protocol is composed of the following steps: (i) conjugation of target capture molecules and barcode DNA strands onto silica microparticles, (ii) target capture with probes, (iii) separation and release of barcode DNA strands from the separated probes, (iv) detection of released barcode DNA using DNA-modified gold nanoparticle probes and (v) red-to-blue color change analysis with a graphic software. Actual target detection and quantification steps with premade probes take approximately 3 h (whole protocol including probe preparations takes approximately 3 days).

  11. Colorimetric on-line control of U

    International Nuclear Information System (INIS)

    Perez, J.J.; Boisde, G.; Dedaldechamp, P.; Dureault, B.

    The instrumentation developed for the automatic colorimetric control of U is presented. Two techniques are used: absorptiometry of U ions using optical probes enabling to measure in situ the solutions containing 0.5 g U(IV)/l or 1 g U(VI)/l; colorimetry of the U-DBM complexe after separation of U by TOPO (this technique is applied to the control of U at the ppm level). The automatic devices used are described. They are experimented in laboratory or in pilot-plant [fr

  12. Estimation of polyclonal IgG4 hybrids in normal human serum.

    Science.gov (United States)

    Young, Elizabeth; Lock, Emma; Ward, Douglas G; Cook, Alexander; Harding, Stephen; Wallis, Gregg L F

    2014-07-01

    The in vivo or in vitro formation of IgG4 hybrid molecules, wherein the immunoglobulins have exchanged half molecules, has previously been reported under experimental conditions. Here we estimate the incidence of polyclonal IgG4 hybrids in normal human serum and comment on the existence of IgG4 molecules with different immunoglobulin light chains. Polyclonal IgG4 was purified from pooled or individual donor human sera and sequentially fractionated using light-chain affinity and size exclusion chromatography. Fractions were analysed by SDS-PAGE, immunoblotting, ELISA, immunodiffusion and matrix-assisted laser-desorption mass spectrometry. Polyclonal IgG4 purified from normal serum contained IgG4κ, IgG4λ and IgG4κ/λ molecules. Size exclusion chromatography showed that IgG4 was principally present in monomeric form (150 000 MW). SDS-PAGE, immunoblotting and ELISA showed the purity of the three IgG4 samples. Immunodiffusion, light-chain sandwich ELISA and mass spectrometry demonstrated that both κ and λ light chains were present on only the IgG4κ/λ molecules. The amounts of IgG4κ/λ hybrid molecules ranged from 21 to 33% from the five sera analysed. Based on the molecular weight these molecules were formed of two IgG4 heavy chains plus one κ and one λ light chain. Polyclonal IgG (IgG4-depleted) was similarly fractionated according to light-chain specificity. No evidence of hybrid IgG κ/λ antibodies was observed. These results indicate that hybrid IgG4κ/λ antibodies compose a substantial portion of IgG4 from normal human serum. © 2014 John Wiley & Sons Ltd.

  13. Thermodynamic parameters for binding of fatty acids to human serum albumin

    DEFF Research Database (Denmark)

    Pedersen, A O; Honoré, B; Brodersen, R

    1990-01-01

    Binding of laurate and myristate anions to human serum albumin has been studied over a range of temperatures, 5-37 degrees C, at pH 7.4. The binding curves indicate that the strength of binding of the first few molecules of fatty acid to albumin (r less than 5) decreases with increasing temperatu...

  14. Parathyroid hormone related protein concentration in human serum and CSF correlates with age.

    Science.gov (United States)

    Kushnir, Mark M; Peterson, Lisa K; Strathmann, Frederick G

    2018-02-01

    Parathyroid Hormone-Related Protein (PTHrP) is involved in intracellular calcium (Ca) regulation, and has been demonstrated to participate in regulation of Ca in brain cells, activation of neurons, and modulation of pain. However, there are conflicting reports regarding the presence of PTHrP in CSF. PTHrP and Ca were quantified in paired CSF and serum samples using mass spectrometry-based methods. Associations between PTHrP and Ca concentrations with age, sex and concentrations of nine CSF diagnostic markers in a set of 140 paired serum and CSF patient samples were evaluated. The observed median PTHrP concentration in CSF was 51 times higher than in serum; the median concentration of Ca in CSF was 1.8 times lower than in serum. We observed positive correlation between concentrations of PTHrP in CSF and serum (p=0.013). Distribution of PTHrP concentrations in serum was associated with age (p=0.0068) and the concentrations were higher in women. In samples with serum calcium concentrations within the reference intervals (n=118), central 95% distribution of concentrations for Ca-CSF, PTHrP-serum and PTHrP-CSF were 5.4 (4.5-6.1) mg/dL, 1.2 (0.5-2.5) pmol/L, 62 (22-125) pmol/L, respectively. Our data demonstrate that PTHrP is a normal constituent of human CSF with median concentrations 51 fold higher than in serum. Elevated serum PTHrP concentrations were positively correlated with age and significantly higher in women. Our data suggest that CSF could be a significant source of circulating PTHrP. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  15. Color dependence with horizontal-viewing angle and colorimetric characterization of two displays using different backlighting

    Science.gov (United States)

    Castro, José J.; Pozo, Antonio M.; Rubiño, Manuel

    2013-11-01

    In this work we studied the color dependence with a horizontal-viewing angle and colorimetric characterization of two liquid-crystal displays (LCD) using two different backlighting: Cold Cathode Fluorescent Lamps (CCFLs) and light-emitting diodes (LEDs). The LCDs studied had identical resolution, size, and technology (TFT - thin film transistor). The colorimetric measurements were made with the spectroradiometer SpectraScan PR-650 following the procedure recommended in the European guideline EN 61747-6. For each display, we measured at the centre of the screen the chromaticity coordinates at horizontal viewing angles of 0, 20, 40, 60 and 80 degrees for the achromatic (A), red (R), green (G) and blue (B) channels. Results showed a greater color-gamut area for the display with LED backlight, compared with the CCFL backlight, showing a greater range of colors perceptible by human vision. This color-gamut area diminished with viewing angle for both displays. Higher differences between trends for viewing angles were observed in the LED-backlight, especially for the R- and G-channels, demonstrating a higher variability of the chromaticity coordinates with viewing angle. The best additivity was reached by the LED-backlight display (a lower error percentage). LED-backlight display provided better color performance of visualization.

  16. A novel immunological assay for hepcidin quantification in human serum.

    Directory of Open Access Journals (Sweden)

    Vasiliki Koliaraki

    Full Text Available BACKGROUND: Hepcidin is a 25-aminoacid cysteine-rich iron regulating peptide. Increased hepcidin concentrations lead to iron sequestration in macrophages, contributing to the pathogenesis of anaemia of chronic disease whereas decreased hepcidin is observed in iron deficiency and primary iron overload diseases such as hereditary hemochromatosis. Hepcidin quantification in human blood or urine may provide further insights for the pathogenesis of disorders of iron homeostasis and might prove a valuable tool for clinicians for the differential diagnosis of anaemia. This study describes a specific and non-operator demanding immunoassay for hepcidin quantification in human sera. METHODS AND FINDINGS: An ELISA assay was developed for measuring hepcidin serum concentration using a recombinant hepcidin25-His peptide and a polyclonal antibody against this peptide, which was able to identify native hepcidin. The ELISA assay had a detection range of 10-1500 microg/L and a detection limit of 5.4 microg/L. The intra- and interassay coefficients of variance ranged from 8-15% and 5-16%, respectively. Mean linearity and recovery were 101% and 107%, respectively. Mean hepcidin levels were significantly lower in 7 patients with juvenile hemochromatosis (12.8 microg/L and 10 patients with iron deficiency anemia (15.7 microg/L and higher in 7 patients with Hodgkin lymphoma (116.7 microg/L compared to 32 age-matched healthy controls (42.7 microg/L. CONCLUSIONS: We describe a new simple ELISA assay for measuring hepcidin in human serum with sufficient accuracy and reproducibility.

  17. A study on human serum albumin influence on glycation of fibrinogen

    International Nuclear Information System (INIS)

    Kielmas, Martyna; Szewczuk, Zbigniew; Stefanowicz, Piotr

    2013-01-01

    Highlights: •The glycation of fibrinogen was investigated by isotopic labeling method. •The potential glycation sites in fibrinogen were identified. •Human serum albumin (HSA) inhibits the glycation of fibrinogen. •The effect of HSA on fibrinogen glycation is sequence-dependent. -- Abstract: Although in vivo glycation proceeds in complex mixture of proteins, previous studies did not take in consideration the influence of protein–protein interaction on Maillard reaction. The aim of our study was to test the influence of human serum albumin (HSA) on glycation of fibrinogen. The isotopic labeling using [ 13 C 6 ] glucose combined with LC-MS were applied as tool for identification possible glycation sites in fibrinogen and for evaluation the effect of HSA on the glycation level of selected amino acids in fibrinogen. The obtained data indicate that the addition of HSA protects the fibrinogen from glycation. The level of glycation in presence of HSA is reduced by 30–60% and depends on the location of glycated residue in sequence of protein

  18. A study on human serum albumin influence on glycation of fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Kielmas, Martyna; Szewczuk, Zbigniew; Stefanowicz, Piotr, E-mail: Piotr.stefanowicz@chem.uni.wroc.pl

    2013-09-13

    Highlights: •The glycation of fibrinogen was investigated by isotopic labeling method. •The potential glycation sites in fibrinogen were identified. •Human serum albumin (HSA) inhibits the glycation of fibrinogen. •The effect of HSA on fibrinogen glycation is sequence-dependent. -- Abstract: Although in vivo glycation proceeds in complex mixture of proteins, previous studies did not take in consideration the influence of protein–protein interaction on Maillard reaction. The aim of our study was to test the influence of human serum albumin (HSA) on glycation of fibrinogen. The isotopic labeling using [{sup 13}C{sub 6}] glucose combined with LC-MS were applied as tool for identification possible glycation sites in fibrinogen and for evaluation the effect of HSA on the glycation level of selected amino acids in fibrinogen. The obtained data indicate that the addition of HSA protects the fibrinogen from glycation. The level of glycation in presence of HSA is reduced by 30–60% and depends on the location of glycated residue in sequence of protein.

  19. Multiple binding of bilirubin to human serum albumin and cobinding with laurate

    DEFF Research Database (Denmark)

    Sato, H; Honoré, B; Brodersen, R

    1988-01-01

    Numerical analysis of multiple binding of two ligands to one carrier has been accomplished, using the principle of several sets of acceptable binding constants, with bilirubin-laurate-albumin as an example. Binding of bilirubin to defatted human serum albumin was investigated by a spectroscopic...

  20. Impacts of daily intakes on the isomeric profiles of perfluoroalkyl substances (PFASs) in human serum.

    Science.gov (United States)

    Shan, Guoqiang; Wang, Zhi; Zhou, Lianqiu; Du, Pin; Luo, Xiaoxiao; Wu, Qiannian; Zhu, Lingyan

    2016-01-01

    Perfluoroalkyl substances (PFASs) have been well studied in human daily intake for assessment of potential health risks. However, little is known about the isomeric compositions of PFASs in daily intake and their impacts on isomeric profiles in humans. In this study, we investigated the occurrence of PFASs with isomeric analysis in various human exposure matrices including foodstuffs, tap water and indoor dust. Perfluorooctanesulfonate (PFOS) and/or perfluorooctanoate (PFOA) were predominant in these exposure matrices collected in Tianjin, China. In fish and meat, linear (n-) PFOA was enriched with a percentage of 92.2% and 99.6%, respectively. Although n-PFOS was higher in fish (84.8%) than in technical PFOS (ca. 70%), it was much lower in meat (63.1%) and vegetables (58.5%). Dietary intake contributed >99% of the estimated daily intake (EDI) for the general population. The isomeric profiles of PFOA and PFOS in human serum were predicted based on the EDI and a one-compartment, first-order pharmacokinetic model. The isomeric percentage of n-PFOA in the EDI (98.6%) was similar to that in human serum (predicted: 98.2%, previously measured: 99.7%) of Tianjin residents. The results suggest direct PFOA intake plays an important role in its isomeric compositions in humans. For PFOS, the predicted n-PFOS (69.3%) was much higher than the previously measured values (59.2%) in human serum. This implies that other factors, such as indirect exposure to PFOS precursors and multiple excretion pathways, may contribute to the lower percentage of n-PFOS in humans than of technical PFOS. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. 24-hour human urine and serum profiles of bisphenol A: Evidence against sublingual absorption following ingestion in soup

    Energy Technology Data Exchange (ETDEWEB)

    Teeguarden, Justin G., E-mail: jt@pnl.gov [Health Effects and Exposure Science, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 93771 (United States); Twaddle, Nathan C., E-mail: nathan.twaddle@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Churchwell, Mona I., E-mail: mona.churchwell@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Yang, Xiaoxia, E-mail: xiaoxia.yang@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Fisher, Jeffrey W., E-mail: jeffrey.fisher@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Seryak, Liesel M., E-mail: seryak.2@osu.edu [Division of Epidemiology, College of Public Health, The Ohio State University, Columbus, OH 43210 (United States); Doerge, Daniel R., E-mail: daniel.doerge@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States)

    2015-10-15

    Extensive first-pass metabolism of ingested bisphenol A (BPA) in the gastro-intestinal tract and liver restricts blood concentrations of bioactive BPA to < 1% of total BPA in humans and non-human primates. Absorption of ingested BPA through non-metabolizing tissues of the oral cavity, recently demonstrated in dogs, could lead to the higher serum BPA concentrations reported in some human biomonitoring studies. We hypothesized that the extensive interaction with the oral mucosa by a liquid matrix, like soup, relative to solid food or capsules, might enhance absorption through non-metabolizing oral cavity tissues in humans, producing higher bioavailability and higher serum BPA concentrations. Concurrent serum and urine concentrations of d6-BPA, and its glucuronide and sulfate conjugates, were measured over a 24 hour period in 10 adult male volunteers following ingestion of 30 μg d6-BPA/kg body weight in soup. Absorption of d6-BPA was rapid (t{sub 1/2} = 0.45 h) and elimination of the administered dose was complete 24 h post-ingestion, evidence against any tissue depot for BPA. The maximum serum d6-BPA concentration was 0.43 nM at 1.6 h after administration and represented < 0.3% of total d6-BPA. Pharmacokinetic parameters, pharmacokinetic model simulations, and the significantly faster appearance half-life of d6-BPA-glucuronide compared to d6-BPA (0.29 h vs 0.45 h) were evidence against meaningful absorption of BPA in humans through any non-metabolizing tissue (< 1%). This study confirms that typical exposure to BPA in food produces picomolar to subpicomolar serum BPA concentrations in humans, not nM concentrations reported in some biomonitoring studies.

  2. 24-hour human urine and serum profiles of bisphenol A: Evidence against sublingual absorption following ingestion in soup

    International Nuclear Information System (INIS)

    Teeguarden, Justin G.; Twaddle, Nathan C.; Churchwell, Mona I.; Yang, Xiaoxia; Fisher, Jeffrey W.; Seryak, Liesel M.; Doerge, Daniel R.

    2015-01-01

    Extensive first-pass metabolism of ingested bisphenol A (BPA) in the gastro-intestinal tract and liver restricts blood concentrations of bioactive BPA to < 1% of total BPA in humans and non-human primates. Absorption of ingested BPA through non-metabolizing tissues of the oral cavity, recently demonstrated in dogs, could lead to the higher serum BPA concentrations reported in some human biomonitoring studies. We hypothesized that the extensive interaction with the oral mucosa by a liquid matrix, like soup, relative to solid food or capsules, might enhance absorption through non-metabolizing oral cavity tissues in humans, producing higher bioavailability and higher serum BPA concentrations. Concurrent serum and urine concentrations of d6-BPA, and its glucuronide and sulfate conjugates, were measured over a 24 hour period in 10 adult male volunteers following ingestion of 30 μg d6-BPA/kg body weight in soup. Absorption of d6-BPA was rapid (t 1/2 = 0.45 h) and elimination of the administered dose was complete 24 h post-ingestion, evidence against any tissue depot for BPA. The maximum serum d6-BPA concentration was 0.43 nM at 1.6 h after administration and represented < 0.3% of total d6-BPA. Pharmacokinetic parameters, pharmacokinetic model simulations, and the significantly faster appearance half-life of d6-BPA-glucuronide compared to d6-BPA (0.29 h vs 0.45 h) were evidence against meaningful absorption of BPA in humans through any non-metabolizing tissue (< 1%). This study confirms that typical exposure to BPA in food produces picomolar to subpicomolar serum BPA concentrations in humans, not nM concentrations reported in some biomonitoring studies.

  3. Selective analysis of human serum albumin based on SEC-ICP-MS after labelling with iophenoxic acid

    DEFF Research Database (Denmark)

    Dersch, Julie Maria; Nguyen, Tam T. T. N.; Østergaard, Jesper

    2015-01-01

    Human serum albumin (HSA) is the most abundant protein in the human plasma. HSA has several physiological roles in the human body, including storage and transport. Owing to the predominance of albumin in plasma, HSA is often involved in the protein binding of drugs. The aim of this work was to de...... plasma and urine samples and for studying the binding of cisplatin to proteins in the human plasma.......Human serum albumin (HSA) is the most abundant protein in the human plasma. HSA has several physiological roles in the human body, including storage and transport. Owing to the predominance of albumin in plasma, HSA is often involved in the protein binding of drugs. The aim of this work...... was to develop a selective, quantitative method for determining albumin in plasma with the purpose of clarifying the fate of metal-based drugs in biological systems. The method can also be applied for determination of urine albumin, which is of relevance in diagnostics of kidney disease. A selective method...

  4. Headspace Solid Phase Micro Extraction Gas Chromatographic Determination of Fenthion in Human Serum

    Directory of Open Access Journals (Sweden)

    Kyriaki Machera

    2008-05-01

    Full Text Available A simple and effective analytical procedure was developed for the determination of fenthion residues in human serum samples. The sample treatment was performed using the headspace solid-phase micro extraction with polyacrylate fiber, which has the advantage to require low amount of serum (1 mL without tedious pre-treatment. The quantification of fenthion was carried out by gas chromatography-mass spectrometry and the recoveries ranged from 79 to 104% at two spiking levels for 6 replicates. Detection and quantification limits were calculated as 1.51 and 4.54 ng/mL of serum respectively. Two fenthion metabolites − fenoxon and fenthion–sulfoxide − were also identified.

  5. Preanalytical and analytical variation of surface-enhanced laser desorption-ionization time-of-flight mass spectrometry of human serum

    DEFF Research Database (Denmark)

    Albrethsen, Jakob; Bøgebo, Rikke; Olsen, Jesper

    2006-01-01

    BACKGROUND: Surface-enhanced laser desorption-ionization time-of-flight (SELDI-TOF) mass spectrometry of human serum is a potential diagnostic tool in human diseases. In the present study, the preanalytical and analytical variation of SELDI-TOF mass spectrometry of serum was assessed in healthy...... was 18% (6%-34%, n=4) for 16 peaks, and inter-individual CV was 38% (16%-56%, n=16) for 20 peaks. CONCLUSIONS: The pre-analytical and analytical conditions of SELDI-TOF mass spectrometry of serum have a significant impact on the protein peaks, with the number of peaks low and the assay variation high...

  6. Ultrasensitive colorimetric detection of heparin based on self-assembly of gold nanoparticles on graphene oxide.

    Science.gov (United States)

    Fu, Xiuli; Chen, Lingxin; Li, Jinhua

    2012-08-21

    A novel colorimetric method was developed for ultrasensitive detection of heparin based on self-assembly of gold nanoparticles (AuNPs) onto the surface of graphene oxide (GO). Polycationic protamine was used as a medium for inducing the self-assembly of citrate-capped AuNPs on GO through electrostatic interaction, resulting in a shift in the surface plasmon resonance (SPR) absorption of AuNPs and exhibiting a blue color. Addition of polyanionic heparin disturbed the self-assemble of AuNPs due to its strong affinity to protamine. With the increase of heparin concentration, the amounts of self-assembly AuNPs decreased and the color changed from blue to red in solution. Therefore, a "blue-to-red" colorimetric sensing strategy based on self-assembly of AuNPs could be established for heparin detection. Compared with the commonly reported aggregation-based methods ("red-to-blue"), the color change from blue to red was more eye-sensitive, especially in low concentration of target. Moreover, stronger interaction between protamine and heparin led to distinguish heparin from its analogues as well as various potentially coexistent physiological species. The strategy was simply achieved by the self-assembly nature of AuNPs and the application of two types of polyionic media, showing it to be label-free, simple, rapid and visual. This method could selectively detect heparin with a detection limit of 3.0 ng mL(-1) in standard aqueous solution and good linearity was obtained over the range 0.06-0.36 μg mL(-1) (R = 0.9936). It was successfully applied to determination of heparin in fetal bovine serum samples as low as 1.7 ng mL(-1) with a linear range of 0-0.8 μg mL(-1).

  7. The human serum metabolome of vitamin B-12 deficiency and repletion, and associations with neurological function

    Science.gov (United States)

    We characterize the human serum metabolome in sub-clinical vitamin B-12 (B-12) deficiency and repletion. A pre-post treatment study provided one injection of 10 mg B-12 to 27 community-dwelling elderly Chileans with B-12 deficiency evaluated with serum B-12, plasma homocysteine, methylmalonic acid a...

  8. Complexity of Complement Resistance Factors Expressed by Acinetobacter baumannii Needed for Survival in Human Serum.

    Science.gov (United States)

    Sanchez-Larrayoz, Amaro F; Elhosseiny, Noha M; Chevrette, Marc G; Fu, Yang; Giunta, Peter; Spallanzani, Raúl G; Ravi, Keerthikka; Pier, Gerald B; Lory, Stephen; Maira-Litrán, Tomás

    2017-10-15

    Acinetobacter baumannii is a bacterial pathogen with increasing impact in healthcare settings, due in part to this organism's resistance to many antimicrobial agents, with pneumonia and bacteremia as the most common manifestations of disease. A significant proportion of clinically relevant A. baumannii strains are resistant to killing by normal human serum (NHS), an observation supported in this study by showing that 12 out of 15 genetically diverse strains of A. baumannii are resistant to NHS killing. To expand our understanding of the genetic basis of A. baumannii serum resistance, a transposon (Tn) sequencing (Tn-seq) approach was used to identify genes contributing to this trait. An ordered Tn library in strain AB5075 with insertions in every nonessential gene was subjected to selection in NHS. We identified 50 genes essential for the survival of A. baumannii in NHS, including already known serum resistance factors, and many novel genes not previously associated with serum resistance. This latter group included the maintenance of lipid asymmetry genetic pathway as a key determinant in protecting A. baumannii from the bactericidal activity of NHS via the alternative complement pathway. Follow-up studies validated the role of eight additional genes identified by Tn-seq in A. baumannii resistance to killing by NHS but not by normal mouse serum, highlighting the human species specificity of A. baumannii serum resistance. The identification of a large number of genes essential for serum resistance in A. baumannii indicates the degree of complexity needed for this phenotype, which might reflect a general pattern that pathogens rely on to cause serious infections. Copyright © 2017 by The American Association of Immunologists, Inc.

  9. Colorimetric detection of Cucumber green mottle mosaic virus using unmodified gold nanoparticles as colorimetric probes.

    Science.gov (United States)

    Wang, Lin; Liu, Zhanmin; Xia, Xueying; Yang, Cuiyun; Huang, Junyi; Wan, Sibao

    2017-05-01

    Cucumber green mottle mosaic virus (CGMMV)causes a severe mosaic symptom of watermelon and cucumber, and can be transmitted via infected cucumber seeds, leaves and soil. It remains a challenge to detect this virus to prevent its introduction and infection and spread in fields. For this purpose, a simple and sensitive label-free colorimetric detection method for CGMMV has been developed with unmodified gold nanoparticles (AuNPs) as colorimetric probes. The method is based on the finding that the presence of RT-PCR target products of CGMMV and species-specific probes results in color change of AuNPs from red to blue after NaCl induction. Normally, species-specific probes attach to the surface of AuNPs and thereby increasing their resistance to NaCl-induced aggregation. The concentration of sodium, probes in the reaction system and evaluation of specificity and sensitivity of a novel assay, visual detection of Cucumber green mottle mosaic virus using unmodified AuNPs has been carried out with simple preparation of samples in our study. Through this assay, as low as 30pg/μL of CGMMV RNA was thus detected visually, by the naked eye, without the need for any sophisticated, expensive instrumentation and biochemical reagents. The specificity was 100% and exhibited good reproducibility in our assays. The results note that this assay is highly species-specific, simple, low-cost, and visual for easy detection of CGMMV in plant tissues. Therefore, visual assay is a potentially useful tool for middle or small-scales corporations and entry-exit inspection and quarantine bureau to detect CGMMV in cucumber seeds or plant tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Improved detection of chemical substances from colorimetric sensor data using probabilistic machine learning

    Science.gov (United States)

    Mølgaard, Lasse L.; Buus, Ole T.; Larsen, Jan; Babamoradi, Hamid; Thygesen, Ida L.; Laustsen, Milan; Munk, Jens Kristian; Dossi, Eleftheria; O'Keeffe, Caroline; Lässig, Lina; Tatlow, Sol; Sandström, Lars; Jakobsen, Mogens H.

    2017-05-01

    We present a data-driven machine learning approach to detect drug- and explosives-precursors using colorimetric sensor technology for air-sampling. The sensing technology has been developed in the context of the CRIM-TRACK project. At present a fully- integrated portable prototype for air sampling with disposable sensing chips and automated data acquisition has been developed. The prototype allows for fast, user-friendly sampling, which has made it possible to produce large datasets of colorimetric data for different target analytes in laboratory and simulated real-world application scenarios. To make use of the highly multi-variate data produced from the colorimetric chip a number of machine learning techniques are employed to provide reliable classification of target analytes from confounders found in the air streams. We demonstrate that a data-driven machine learning method using dimensionality reduction in combination with a probabilistic classifier makes it possible to produce informative features and a high detection rate of analytes. Furthermore, the probabilistic machine learning approach provides a means of automatically identifying unreliable measurements that could produce false predictions. The robustness of the colorimetric sensor has been evaluated in a series of experiments focusing on the amphetamine pre-cursor phenylacetone as well as the improvised explosives pre-cursor hydrogen peroxide. The analysis demonstrates that the system is able to detect analytes in clean air and mixed with substances that occur naturally in real-world sampling scenarios. The technology under development in CRIM-TRACK has the potential as an effective tool to control trafficking of illegal drugs, explosive detection, or in other law enforcement applications.

  11. Amperometric magnetoimmunoassay for the direct detection of tumor necrosis factor alpha biomarker in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Eletxigerra, U. [Micro-NanoFabrication Unit, IK4-Tekniker, Eibar (Spain); CIC microGUNE, Arrasate-Mondragón (Spain); Martinez-Perdiguero, J. [CIC microGUNE, Arrasate-Mondragón (Spain); Merino, S. [Micro-NanoFabrication Unit, IK4-Tekniker, Eibar (Spain); CIC microGUNE, Arrasate-Mondragón (Spain); Villalonga, R.; Pingarrón, J.M. [Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Madrid (Spain); Campuzano, S., E-mail: susanacr@quim.ucm.es [Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Madrid (Spain)

    2014-08-01

    Highlights: • Electrochemical magnetoimmunosensor for tumor necrosis factor alpha (TNFα) biomarker. • Sensitive and selective detection of TNFα in undiluted serum. • LOD achieved lower than the cut-off value established for relevant illnesses. • Useful and affordable alternative to ELISAs for TNFα determination in serum. - Abstract: An amperometric immunoassay for the determination of tumor necrosis factor alpha (TNFα) protein biomarker in human serum based on the use of magnetic microbeads (MBs) and disposable screen-printed carbon electrodes (SPCEs) has been developed. The specifically modified microbeads were magnetically captured on the working electrode surface and the amperometric responses were measured at −0.20 V (vs. Ag pseudo-reference electrode), upon addition of hydroquinone (HQ) as electron transfer mediator and H{sub 2}O{sub 2} as the enzyme substrate. After a thorough optimization of the assay, extremely low limits of detection were achieved: 2.0 pg mL{sup −1} (36 fM) and 5.8 pg mL{sup −1} (105 fM) for standard solutions and spiked human serum, respectively. The simplicity, robustness and this clinically interesting LOD proved the developed TNFα immunoassay as a good contender for real clinical application.

  12. Amperometric magnetoimmunoassay for the direct detection of tumor necrosis factor alpha biomarker in human serum

    International Nuclear Information System (INIS)

    Eletxigerra, U.; Martinez-Perdiguero, J.; Merino, S.; Villalonga, R.; Pingarrón, J.M.; Campuzano, S.

    2014-01-01

    Highlights: • Electrochemical magnetoimmunosensor for tumor necrosis factor alpha (TNFα) biomarker. • Sensitive and selective detection of TNFα in undiluted serum. • LOD achieved lower than the cut-off value established for relevant illnesses. • Useful and affordable alternative to ELISAs for TNFα determination in serum. - Abstract: An amperometric immunoassay for the determination of tumor necrosis factor alpha (TNFα) protein biomarker in human serum based on the use of magnetic microbeads (MBs) and disposable screen-printed carbon electrodes (SPCEs) has been developed. The specifically modified microbeads were magnetically captured on the working electrode surface and the amperometric responses were measured at −0.20 V (vs. Ag pseudo-reference electrode), upon addition of hydroquinone (HQ) as electron transfer mediator and H 2 O 2 as the enzyme substrate. After a thorough optimization of the assay, extremely low limits of detection were achieved: 2.0 pg mL −1 (36 fM) and 5.8 pg mL −1 (105 fM) for standard solutions and spiked human serum, respectively. The simplicity, robustness and this clinically interesting LOD proved the developed TNFα immunoassay as a good contender for real clinical application

  13. Micro-bead injection spectroscopy for label-free automated determination of immunoglobulin G in human serum.

    Science.gov (United States)

    Ramos, Inês I; Magalhães, Luís M; Barreiros, Luisa; Reis, Salette; Lima, José L F C; Segundo, Marcela A

    2018-01-01

    Immunoglobulin G (IgG) represents the major fraction of antibodies in healthy adult human serum, and deviations from physiological levels are a generic marker of disease corresponding to different pathologies. Therefore, screening methods for IgG evaluation are a valuable aid to diagnostics. The present work proposes a rapid, automatic, and miniaturized method based on UV-vis micro-bead injection spectroscopy (μ-BIS) for the real-time determination of human serum IgG with label-free detection. Relying on attachment of IgG in rec-protein G immobilized in Sepharose 4B, a bioaffinity column is automatically assembled, where IgG is selectively retained and determined by on-column optical density measurement. A "dilution-and-shoot" approach (50 to 200 times) was implemented without further sample treatment because interferences were flushed out of the column upon sample loading, with minimization of carryover and cross-contamination by automatically discarding the sorbent (0.2 mg) after each determination. No interference from human serum albumin at 60 mg mL -1 in undiluted sample was found. The method allowed IgG determination in the range 100-300 μg mL -1 (corresponding to 5.0-60 mg mL -1 in undiluted samples), with a detection limit of 33 μg mL -1 (1.7 mg mL -1 for samples, dilution factor of 50). RSD values were time-to-result decreased from several hours to times, showing the potential of the proposed approach as a point-of-care method. Graphical abstract Micro-Bead Injection Spectroscopy method for real time, automated and label-free determination of total serum human Immunoglobulin G (IgG). The method was designed for Lab-on-Valve (LOV) platforms using a miniaturised protein G bioaffinity separative approach. IgG are separated from serum matrix components upon quantification with low non-specific binding in less than 5 min.

  14. Blood pressure and serum creatinine in obese female.

    Science.gov (United States)

    Asrin, M; Nessa, A; Hasan, M I; Das, R K

    2015-01-01

    Obesity is increasing in developed as well as in developing countries. This analytical cross sectional study was carried out to document the relation between blood pressure, serum creatinine and body mass index in female and to assess potential health differences among obese female and normal weight female. This study was done in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2012 to June 2013. Seventy female persons volunteered as subjects. Among them 35 were within normal weight (BMI 18.5-24.9kg/m²) and 35 were obese (BMI≥30kg/m²). Non probability purposive type of sampling technique was used to select the subjects. Measurement of body mass index and blood pressure were done as per procedure. Serum creatinine level was estimated by enzymatic colorimetric method. The results were calculated and analyzed by using SPSS (statistical package for social science, version 17.0), scientific electronic calculator and simultaneously with a computer assisted program like Microsoft excel. Unpaired 't' test was applied to find the significance of difference regarding serum creatinine and blood pressure levels in obese female. The value of p was 1% to indicate highly significant and 5% to indicate simply significant or statistically significant. The mean±SE of systolic blood pressure, diastolic blood pressure and serum creatinine levels were 135.71±1.58mmHg, 88.74±0.95mmHg and 1.03±0.01mg/dl respectively; significant at 1% level for obese group of BMI (phigh BMI is significantly related to increased levels of serum creatinine & blood pressure in obese female which indicate the obese subjects are prone to cardiovascular & metabolic risk.

  15. Comprehensive identification of Vibrio vulnificus genes required for growth in human serum.

    Science.gov (United States)

    Carda-Diéguez, M; Silva-Hernández, F X; Hubbard, T P; Chao, M C; Waldor, M K; Amaro, C

    2018-12-31

    Vibrio vulnificus can be a highly invasive pathogen capable of spreading from an infection site to the bloodstream, causing sepsis and death. To survive and proliferate in blood, the pathogen requires mechanisms to overcome the innate immune defenses and metabolic limitations of this host niche. We created a high-density transposon mutant library in YJ016, a strain representative of the most virulent V. vulnificus lineage (or phylogroup) and used transposon insertion sequencing (TIS) screens to identify loci that enable the pathogen to survive and proliferate in human serum. Initially, genes underrepresented for insertions were used to estimate the V. vulnificus essential gene set; comparisons of these genes with similar TIS-based classification of underrepresented genes in other vibrios enabled the compilation of a common Vibrio essential gene set. Analysis of the relative abundance of insertion mutants in the library after exposure to serum suggested that genes involved in capsule biogenesis are critical for YJ016 complement resistance. Notably, homologues of two genes required for YJ016 serum-resistance and capsule biogenesis were not previously linked to capsule biogenesis and are largely absent from other V. vulnificus strains. The relative abundance of mutants after exposure to heat inactivated serum was compared with the findings from the serum screen. These comparisons suggest that in both conditions the pathogen relies on its Na + transporting NADH-ubiquinone reductase (NQR) complex and type II secretion system to survive/proliferate within the metabolic constraints of serum. Collectively, our findings reveal the potency of comparative TIS screens to provide knowledge of how a pathogen overcomes the diverse limitations to growth imposed by serum.

  16. 24-hour human urine and serum profiles of bisphenol A: Evidence against sublingual absorption following ingestion in soup.

    Science.gov (United States)

    Teeguarden, Justin G; Twaddle, Nathan C; Churchwell, Mona I; Yang, Xiaoxia; Fisher, Jeffrey W; Seryak, Liesel M; Doerge, Daniel R

    2015-10-15

    Extensive first-pass metabolism of ingested bisphenol A (BPA) in the gastro-intestinal tract and liver restricts blood concentrations of bioactive BPA to <1% of total BPA in humans and non-human primates. Absorption of ingested BPA through non-metabolizing tissues of the oral cavity, recently demonstrated in dogs, could lead to the higher serum BPA concentrations reported in some human biomonitoring studies. We hypothesized that the extensive interaction with the oral mucosa by a liquid matrix, like soup, relative to solid food or capsules, might enhance absorption through non-metabolizing oral cavity tissues in humans, producing higher bioavailability and higher serum BPA concentrations. Concurrent serum and urine concentrations of d6-BPA, and its glucuronide and sulfate conjugates, were measured over a 24hour period in 10 adult male volunteers following ingestion of 30μg d6-BPA/kg body weight in soup. Absorption of d6-BPA was rapid (t1/2=0.45h) and elimination of the administered dose was complete 24h post-ingestion, evidence against any tissue depot for BPA. The maximum serum d6-BPA concentration was 0.43nM at 1.6h after administration and represented <0.3% of total d6-BPA. Pharmacokinetic parameters, pharmacokinetic model simulations, and the significantly faster appearance half-life of d6-BPA-glucuronide compared to d6-BPA (0.29h vs 0.45h) were evidence against meaningful absorption of BPA in humans through any non-metabolizing tissue (<1%). This study confirms that typical exposure to BPA in food produces picomolar to subpicomolar serum BPA concentrations in humans, not nM concentrations reported in some biomonitoring studies. Published by Elsevier Inc.

  17. Comparison of serum lipid profile in ischaemic and haemorrhagic stroke

    International Nuclear Information System (INIS)

    Mehmood, A.; Sharif, M.A.

    2010-01-01

    To compare serum lipid profile between patients of ischaemic and haemorrhagic strokes. Study Design: Cross sectional, comparative study. Place and Duration of Study: Military Hospital, Rawalpindi, from August 2004 to February 2005. Methodology: Patients with diagnosis of stroke comprising 100 consecutive patients each of ischaemic and haemorrhagic strokes were included in the study while patients on lipid lowering therapy were excluded from study. To determine the subtype of stroke, clinical examination followed by CT scan of brain was done. A serum sample after 8 hours of overnight fasting was taken on the next day of admission for both groups of patients. Total serum cholesterol, triglycerides, LDL cholesterol, VLDL-cholesterol and HDL-cholesterol was determined, using enzymatic colorimetric method. Statistical analysis was done by comparison of lipid profile in two subgroups, using proportion test for any significant difference. Results: The mean age at presentation of patients with stroke was 64.2+-12 years with a male to female ratio of 3.6:1. In 100 ischaemic stroke patients, raised serum total cholesterol was seen in 42, triglyceride in 04, LDL-cholesterol in 05 and VLDL-cholesterol in 07 patients. Serum HDL-cholesterol was below the normal reference in 31 cases. On the other hand, serum total cholesterol and triglycerides was raised in 05 patients each, LDL-cholesterol in 09 and VLDL-cholesterol in 03 patients of haemorrhagic stroke. Serum HDL-cholesterol was below normal in 04 patients of haemorrhagic stroke. On comparison, there were significantly greater number of patients with raised serum cholesterol and low HDL-cholesterol in ischaemic stroke than haemorrhagic stroke (p < 0.05). No statistical significance was found on comparing serum values of ischaemic and haemorrhagic stroke for triglycerides, LDL-cholesterol and VLDL-cholesterol. Conclusion: Ischaemic stroke patients had high serum total cholesterol and lower HDL-cholesterol levels as compared to

  18. Developing and Demonstrating an Augmented Reality Colorimetric Titration Tool

    Science.gov (United States)

    Tee, Nicholas Yee Kwang; Gan, Hong Seng; Li, Jonathan; Cheong, Brandon Huey-Ping; Tan, Han Yen; Liew, Oi Wah; Ng, Tuck Wah

    2018-01-01

    The handling of chemicals in the laboratory presents a challenge in instructing large class sizes and when students are relatively new to the laboratory environment. In this work, we describe and demonstrate an augmented reality colorimetric titration tool that operates out of the smartphone or tablet of students. It allows multiple students to…

  19. Effect of storage duration on cytokine stability in human serum and plasma.

    Science.gov (United States)

    Vincent, Fabien B; Nim, Hieu T; Lee, Jacinta P W; Morand, Eric F; Harris, James

    2018-06-14

    Quantification of analytes such as cytokines in serum samples is intrinsic to translational research in immune diseases. Optimising pre-analytical conditions is critical for ensuring study quality, including evaluation of cytokine stability. We aimed to evaluate the effect on cytokine stability of storage duration prior to freezing of serum, and compare to plasma samples obtained from patients with systemic lupus erythematosus (SLE). Protein stability was analysed by simultaneously quantifying 18 analytes using a custom multi-analyte profile in SLE patient serum and plasma samples that had been prospectively stored at 4 °C for pre-determined periods between 0 and 30 days, prior to freezing. Six analytes were excluded from analysis, because most tested samples were above or below the limit of detection. Amongst the 12 analysed proteins, 11 did not show significant signal degradation. Significant signal degradation was observed from the fourth day of storage for a single analyte, CCL19. Proteins levels were more stable in unseparated serum compared to plasma for most analytes, with the exception of IL-37 which appears slightly more stable in plasma. Based on this, a maximum 3 days of storage at 4 °C for unseparated serum samples is recommended for biobanked samples intended for cytokine analysis in studies of human immune disease. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Immunoreactive somatomedin A in human serum

    International Nuclear Information System (INIS)

    Hall, K.; Brandt, J.; Enberg, G.; Fryklund, L.

    1979-01-01

    A RIA has been developed for somatomedin A (SM-A) utilizing Sepharose-bound antibodies. This assay, measuring SM-A, the insulin-like growth factors 1 and 2, and somatomedin C, allows determination in serum samples. In comparison with a serum standard, the mean serum levels in patients with acromegaly or GH deficiency and healthy subjects were 8.7 +- 0.7 (n=25), 0.24 +- 0.02 (n=25), and 1.15 +- 0.11 U/ml, respectively. The correlation coefficient between immunoreactive SM-A and SM-A by radioreceptor assay was highly significant (r=0.93), although the potency ratio of SM-A between the two groups of patients was higher in the RIA than in the radioreceptor assay. Gel chromatography revealed that SM-A in acromegalic serum is bound to a carrier protein which is absent in patients with GH deficiency. After gel chromatography at low pH, 90% of applied immunoreactive SM-A was recovered in the low molecular weight fraction and consisted mainly of neutral polypeptides

  1. A Colorimetric Method for the Determination of the Exhaustion Level of Granular Activated Carbons Used in Rum Production

    Directory of Open Access Journals (Sweden)

    Harold Crespo Sariol

    2016-09-01

    Full Text Available Spectrophotometric measurement applied on saturated granular activated carbon (GAC is not yet explored. A colorimetric method in the visible range has been developed in order to determine the exhaustion level of GAC used in rum production. Aqueous ammonia solution has been used as an indicative agent to determine the extraction rate of taste compounds within the rum production process and the exhaustion degree of the GAC. The colorimetric results showed excellent correlation with the iodine number and the contact pH. The proposed colorimetric method opens possibilities for rum producers to improve the management and economical use of the activated carbon at the industrial scale.

  2. Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals

    DEFF Research Database (Denmark)

    Lizeng, Q; Nilsson, C; Sourial, S

    2004-01-01

    Links Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals.Lizeng Q, Nilsson C, Sourial S, Andersson S, Larsen O, Aaby P, Ehnlund M, Bjorling E. Research Center, South Hospital, Stockholm, Sweden. The mechanisms behind...... the resistance to human immunodeficiency virus type 2 (HIV-2) infection are still not fully understood. In the present study, we explored the HIV-2-specific humoral serum immunoglobulin A (IgA) immune response in HIV-2-exposed IgG-seronegative (EGSN) individuals. Serum samples from heterosexual EGSN individuals...... and their known HIV-2-infected partners, as well as controls originating from Guinea-Bissau in Africa, were studied. Antibody reactivity to native and recombinant envelope glycoproteins was investigated, and the capacity of purified serum IgA to neutralize HIV-2(SBL6669) was tested. Our results showed that 16...

  3. Study of OH● Radicals in Human Serum Blood of Healthy Individuals and Those with Pathological Schizophrenia

    Directory of Open Access Journals (Sweden)

    Wolfgang Linert

    2011-01-01

    Full Text Available The human body is constantly under attack from free radicals that occur as part of normal cell metabolism, and by exposure to environmental factors such as UV light, cigarette smoke, environmental pollutants and gamma radiation. The resulting “Reactive Oxygen Species” (ROS circulate freely in the body with access to all organs and tissues, which can have serious repercussions throughout the body. The body possesses a number of mechanisms both to control the production of ROS and to cope with free radicals in order to limit or repair damage to tissues. Overproduction of ROS or insufficient defense mechanisms leads to a dangerous disbalance in the organism. Thereby several pathomechanisms implicated in over 100 human diseases, e.g., cardiovascular disease, cancer, diabetes mellitus, physiological disease, aging, etc., can be induced. Thus, a detailed investigation on the quantity of oxygen radicals, such as hydroxyl radicals (OH● in human serum blood, and its possible correlation with antioxidant therapy effects, is highly topical. The subject of this study was the influence of schizophrenia on the amount of OH● in human serum blood. The radicals were detected by fluorimetry, using terephthalic acid as a chemical trap. For all experiments the serum blood of healthy people was used as a control group.

  4. Platelet-rich plasma can replace fetal bovine serum in human meniscus cell cultures

    NARCIS (Netherlands)

    Gonzales, V.K.; Mulder, E.L.W. de; Boer, T. den; Hannink, G.; Tienen, T.G. van; Heerde, W.L. van; Buma, P.

    2013-01-01

    Concerns over fetal bovine serum (FBS) limit the clinical application of cultured tissue-engineered constructs. Therefore, we investigated if platelet-rich plasma (PRP) can fully replace FBS for meniscus tissue engineering purposes. Human PRP and platelet-poor plasma (PPP) were isolated from three

  5. Human skin condition and its associations with nutrient concentrations in serum and diet

    NARCIS (Netherlands)

    Boelsma, E.; Vijver, L.P.L. van de; Goldbohm, R.A.; Klöpping-Ketelaars, I.A.A.; Hendriks, H.F.J.; Roza, L.

    2003-01-01

    Background: Nutritional factors exert promising actions on the skin, but only scant information is available on the modulating effects of physiologic concentrations of nutrients on the skin condition of humans. Objective: The objective was to evaluate whether nutrient concentrations in serum and

  6. In vitro biotransformation of tris(2-butoxyethyl) phosphate (TBOEP) in human liver and serum

    Energy Technology Data Exchange (ETDEWEB)

    Van den Eede, Nele, E-mail: nele.vandeneede@uantwerpen.be [Toxicological Center, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp (Belgium); Erratico, Claudio [Toxicological Center, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp (Belgium); Exarchou, Vassiliki [Natural Products & Food Research and Analysis (NatuRA), Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp (Belgium); Maho, Walid; Neels, Hugo [Toxicological Center, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp (Belgium); Covaci, Adrian, E-mail: adrian.covaci@uantwerpen.be [Toxicological Center, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp (Belgium)

    2015-04-15

    Tris(2-butoxyethyl) phosphate (TBOEP) is a plasticizer present in indoor dust, reaching levels of several micrograms per gram. Such levels could lead to significant daily exposure of adults and children. Currently, no toxicokinetic data are available to estimate TBOEP clearance in humans after uptake and therefore, one objective of this study was to investigate intrinsic clearance of TBOEP by human liver microsome (HLM) and serum enzymes. Another objective was to generate information to identify and prioritize several metabolites of TBOEP for investigation of human exposure by biomonitoring. 1D and 2D-NMR methodologies were successfully applied on a mixture of the metabolites to confirm the structure of 3-HO-TBOEP (bis(2-butoxyethyl) 3-hydroxyl-2-butoxyethyl phosphate) and to tentatively assign structures to 1-HO-TBOEP and 2-HO-TBOEP. HO-TBOEP isomers and bis(2-butoxyethyl) phosphate (BBOEP), bis(2-butoxyethyl) hydroxyethyl phosphate (BBOEHEP) were further monitored by liquid chromatography–tandem mass spectrometry. Rates of formation of BBOEHEP and HO-TBOEP metabolites by liver enzymes were best described by the Michaelis–Menten model. Apparent K{sub m} values for BBOEHEP, 3-HO-TBOEP, and sum of 1- and 2-HO-TBOEP isomer formation were 152, 197 and 148 μM, respectively. Apparent V{sub max} values for the formation of BBOEHEP, 3-HO-TBOEP, and the sum of 1- and 2-HO-TBOEP isomers were 2560, 643, and 254 pmol/min/mg protein, respectively. No detectable formation of BBOEP occurred with liver or serum enzymes. Our findings indicate that intrinsic clearance of TBOEP is mainly catalyzed by oxidative enzymes in the liver and that its major in vitro metabolite is BBOEHEP. These findings can be applied in human biomonitoring studies and risk assessment. - Highlights: • First steps in the elucidation of TBOEP toxicokinetics • Quantification of TBOEP metabolites in human serum and liver microsomes • No detectable formation of BBOEP occurred with liver or serum

  7. Displacement of Drugs from Human Serum Albumin: From Molecular Interactions to Clinical Significance.

    Science.gov (United States)

    Rimac, Hrvoje; Debeljak, Željko; Bojić, Mirza; Miller, Larisa

    2017-01-01

    Human serum albumin (HSA) is the most abundant protein in human serum. It has numerous functions, one of which is transport of small hydrophobic molecules, including drugs, toxins, nutrients, hormones and metabolites. HSA has the ability to interact with a wide variety of structurally different compounds. This promiscuous, nonspecific affinity can lead to sudden changes in concentrations caused by displacement, when two or more compounds compete for binding to the same molecular site. It is important to consider drug combinations and their binding to HSA when defining dosing regimens, as this can directly influence drug's free, active concentration in blood. In present paper we review drug interactions with potential for displacement from HSA, situations in which they are likely to occur and their clinical significance. We also offer guidelines in designing drugs with decreased binding to HSA. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. A simple and selective colorimetric mercury (II) sensing system based on chitosan stabilized gold nanoparticles and 2,6-pyridinedicarboxylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Kun; Siegel, Gene; Tiwari, Ashutosh, E-mail: tiwari@eng.utah.edu

    2017-02-01

    The development of simple and cost-effective methods for the detection and treatment of Hg{sup 2+} in the environment is an important area of research due to the serious health risk that Hg{sup 2+} poses to humans. Colorimetric sensing based on the induced aggregation of nanoparticles is of great interest since it offers a low cost, simple, and relatively rapid procedure, making it perfect for on-site analysis. Herein we report the development of a simple colorimetric sensor for the selective detection and estimation of mercury ions in water, based on chitosan stabilized gold nanoparticles (AuNPs) and 2,6-pyridinedicarboxylic acid (PDA). In the presence of Hg{sup 2+}, PDA induces the aggregation of AuNPs, causing the solution to change colors varying from red to blue, depending on the concentration of Hg{sup 2+}. The formation of aggregated AuNPs in the presence of Hg{sup 2+} was confirmed using transmission electron microscopy (TEM) and UV–Vis spectroscopy. The method exhibits linearity in the range of 300 nM to 5 μM and shows excellent selectivity towards Hg{sup 2+} among seventeen different metal ions and was successfully applied for the detection of Hg{sup 2+} in spiked river water samples. The developed technique is simple and superior to the existing techniques in that it allows detection of Hg{sup 2+} using the naked eye and simple and rapid colorimetric analysis, which eliminates the need for sophisticated instruments and sample preparation methods. - Highlights: • A simple colorimetric method for detection of Hg{sup 2+} in water was proposed. • Au nanoparticles and 2,6-pyridinedicarboxylic acid were used for sensing Hg{sup 2+}. • Sensing mechanisms were demonstrated by TEM and UV–Visible measurements. • It showed the solution color changes from red to blue upon addition of Hg{sup 2+}. • The method selectively detected Hg{sup 2+} among seventeen different metal ions.

  9. Metabonomic profiling of renal cell carcinoma: High-resolution proton nuclear magnetic resonance spectroscopy of human serum with multivariate data analysis

    International Nuclear Information System (INIS)

    Gao Hongchang; Dong Baijun; Liu Xia; Xuan Hanqing; Huang Yiran; Lin Donghai

    2008-01-01

    Metabonomic profiling using proton nuclear magnetic resonance ( 1 H NMR) spectroscopy and multivariate data analysis of human serum samples was used to characterize metabolic profiles in renal cell carcinoma (RCC). We found distinct, easily detectable differences between (a) RCC patients and healthy humans, (b) RCC patients with metastases and without metastases, and (c) RCC patients before and after nephrectomy. Compared to healthy human serum, RCC serum had higher levels of lipid (mainly very low-density lipoproteins), isoleucine, leucine, lactate, alanine, N-acetylglycoproteins, pyruvate, glycerol, and unsaturated lipid, together with lower levels of acetoacetate, glutamine, phosphatidylcholine/choline, trimethylamine-N-oxide, and glucose. This pattern was somewhat reversed after nephrectomy. Altered metabolite concentrations are most likely the result of the cells switching to glycolysis to maintain energy homeostasis following the loss of ATP caused by impaired TCA cycle in RCC. Serum NMR spectra combined with principal component analysis techniques offer an efficient, convenient way of depicting tumour biochemistry and stratifying tumours under different pathophysiological conditions. It may be able to assist early diagnosis and postoperative surveillance of human malignant diseases using single blood samples

  10. Ultratrace analysis of polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) in human serum and cerebrospinal fluid (CSF) samples

    Energy Technology Data Exchange (ETDEWEB)

    Takasuga, T.; Senthilkumar, K.; Watanabe, K.; Takemori, H. [Shimadzu Techno Research, Inc., Kyoto (Japan); Shoda, T. [Ehime Univ. Medical Research Center, Matsuyama (Japan); Kuroda, Y. [Tokyo Metropolitan Inst. for Neuroscience, Tokyo (Japan)

    2004-09-15

    In the present study, we established pretreatment and high sensitivity analytical method of polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) in serum and cerebrospinal fluid (CSF) of humans for the first time. Analyzing serum and CSF samples from humans found unique because PCBs behavior and metabolism could be discerned. Furthermore, so far studies reported concentrations of OH-PCBs in wildlife samples obtained by HRGC-LRMS or GC-ECD data. In this study, we established cleanup and analytical methods by high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS) using 1 mL of sample. Mainly, total PCBs and OH-PCBs in the CSF were extracted by specialized developed method. Using this method, PCBs and OH-PCBs could be determined swiftly. Based on this method, major OH-PCB congeners were detected from human, serum, CSF, control serum and Rhesus monkey plasma. Present methodology developed based on the isotope dilution technique using OH-PCBs standard and thus we suggest the present methodology could apply for ultra trace analysis of OHPCBs as well as total PCBs in human samples.

  11. Quantification of antidepressants and antipsychotics in human serum by precipitation and ultra high pressure liquid chromatography-tandem mass spectrometry

    DEFF Research Database (Denmark)

    Hasselstrøm, Jørgen Bo

    2011-01-01

    The present article describes the quantification of mirtazapine, O-desmethylvenlafaxine, quetiapine, venlafaxine, and ziprasidone (group 1), and amitriptyline, citalopram, clomipramine, clozapine, desmethylclomipramine, desipramine, imipramine, and nortriptyline (group 2) in human serum for thera......The present article describes the quantification of mirtazapine, O-desmethylvenlafaxine, quetiapine, venlafaxine, and ziprasidone (group 1), and amitriptyline, citalopram, clomipramine, clozapine, desmethylclomipramine, desipramine, imipramine, and nortriptyline (group 2) in human serum...

  12. Evaluation of human platelet lysate versus fetal bovine serum for culture of mesenchymal stromal cells.

    Science.gov (United States)

    Hemeda, Hatim; Giebel, Bernd; Wagner, Wolfgang

    2014-02-01

    Culture media for therapeutic cell preparations-such as mesenchymal stromal cells (MSCs)-usually comprise serum additives. Traditionally, fetal bovine serum is supplemented in basic research and in most clinical trials. Within the past years, many laboratories adapted their culture conditions to human platelet lysate (hPL), which further stimulates proliferation and expansion of MSCs. Particularly with regard to clinical application, human alternatives for fetal bovine serum are clearly to be preferred. hPL is generated from human platelet units by disruption of the platelet membrane, which is commonly performed by repeated freeze and thaw cycles. Such culture supplements are notoriously ill-defined, and many parameters contribute to batch-to-batch variation in hPL such as different amounts of plasma, a broad range of growth factors and donor-specific effects. The plasma components of hPL necessitate addition of anticoagulants such as heparins to prevent gelatinization of hPL medium, and their concentration must be standardized. Labels for description of hPL-such as "xenogen-free," "animal-free" and "serum free"-are not used consistently in the literature and may be misleading if not critically assessed. Further analysis of the precise composition of relevant growth factors, attachment factors, microRNAs and exosomes will pave the way for optimized and defined culture conditions. The use of hPL has several advantages and disadvantages: they must be taken into account because the choice of cell culture additive has major impact on cell preparations. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  13. Comparison of colorimetry and electrothermal atomic absorption spectroscopy for the quantification of non-transferrin bound iron in human sera.

    Science.gov (United States)

    Jittangprasert, Piyada; Wilairat, Prapin; Pootrakul, Pensri

    2004-12-01

    This paper describes a comparison of two analytical techniques, one employing bathophenanthrolinedisulfonate (BPT), a most commonly-used reagent for Fe (II) determination, as chromogen and an electrothermal atomic absorption spectroscopy (ETAAS) for the quantification of non-transferrin bound iron (NTBI) in sera from thalassemic patients. Nitrilotriacetic acid (NTA) was employed as the ligand for binding iron from low molecular weight iron complexes present in the serum but without removing iron from the transferrin protein. After ultrafiltration the Fe (III)-NTA complex was then quantified by both methods. Kinetic study of the rate of the Fe (II)-BPT complex formation for various excess amounts of NTA ligand was also carried out. The kinetic data show that a minimum time duration (> 60 minutes) is necessary for complete complex formation when large excess of NTA is used. Calibration curves given by colorimetric and ETAAS methods were linear over the range of 0.15-20 microM iron (III). The colorimetric and ETAAS methods exhibited detection limit (3sigma) of 0.13 and 0.14 microM, respectively. The NTBI concentrations from 55 thalassemic serum samples measured employing BPT as chromogen were statistically compared with the results determined by ETAAS. No significant disagreement at 95% confidence level was observed. It is, therefore, possible to select any one of these two techniques for determination of NTBI in serum samples of thalassemic patients. However, the colorimetric procedure requires a longer analysis time because of a slow rate of exchange of NTA ligand with BPT, leading to the slow rate of formation of the colored complex.

  14. Ultrasensitive colorimetric immunoassay for hCG detection based on dual catalysis of Au@Pt core-shell nanoparticle functionalized by horseradish peroxidase

    Science.gov (United States)

    Wang, Weiguo; Zou, Yake; Yan, Jinwu; Liu, Jing; Chen, Huixiong; Li, Shan; Zhang, Lei

    2018-03-01

    In this paper, an ultrasensitive colorimetric biosensor for human chorionic gonadotrophin (hCG) detection was designed from bottom-up method based on the dual catalysis of the horseradish peroxidase (HRP) and Au@Pt nanoparticles (NPs) relative to H2O2-TEM system. HRP and monoclonal mouse anti-hCG antibody (β-submit, mAb1) were co-immobilized onto the Au@Pt NP surface to improve catalytic efficiency and specificity, which formed a dual functionalized Au@Pt-HRP probe with the mean size of 42.8 nm (D50). The colorimetric immunoassay was developed for the hCG detection, and the Au@Pt-HRP probe featured a higher sensitivity in the concentration range of 0.4-12.8 IU L- 1 with a low limit of detection (LOD) of 0.1 IU L- 1 compared with the LODs of 0.8 IU L- 1 for BA-ELISA and of 2.0 IU L- 1 for Au@Pt, which indicated that the Au@Pt-HRP probe possessed higher catalytic efficiency with 2.8-fold increase over Au@Pt and 33.8-fold increase over HRP. Also, the Au@Pt-HRP probe exhibited good precision and reproducibility, high specificity and acceptable accuracy with CV being less than 15%. The dual functionalized Au@Pt-HRP probe as a type of signal amplified method was firstly applied in the colorimetric immunoassay for the hCG detection.

  15. Colorimetric end-tidal CO2 detector for verification of endotracheal tube placement in out-of-hospital cardiac arrest.

    Science.gov (United States)

    Hayden, S R; Sciammarella, J; Viccellio, P; Thode, H; Delagi, R

    1995-06-01

    To evaluate the ability of a disposable, colorimetric end-tidal CO2 detector to verify proper endotracheal (ET) tube placement in out-of-hospital cardiac arrest, and to correlate semiquantitative CO2 measurements with the rate of return of spontaneous circulation (ROSC). Prospective, observational study using a convenience sample of intubated out-of-hospital cardiac arrest patients. A disposable, colorimetric end-tidal CO2 detector was attached to the ET tube after intubation. In the absence of a colorimetric change, the paramedics reassessed the tube placement and could reintubate the patient. Tube placement was verified at the hospital. Paramedics were instructed to contact the base station and report the colorimetric change upon hospital arrival. ROSC was defined as restoration of a self-sustaining pulse until hospital arrival. Between December 1990 and May 1993, ET tubes were placed in 566 victims of out-of-hospital cardiac arrest. 541 of the 566 intubations (95.6%) were associated with a color change. In one case with a color change and out-of-hospital clinical evidence of proper tube placement, the tube was determined to be in the esophagus at the hospital. Correct placement of the remaining 565 of 566 (99.8%) tubes was verified. Of the 566 patients who had a colorimetric change, 91 (16%) had ROSC vs one of 25 (4%) patients who did not have a color change. In one subgroup (n = 179), the degree of color change was highly associated with ROSC (p = 0.004). A disposable, colorimetric end-tidal CO2 detector appears reliable in verifying proper ET tube placement in victims of out-of-hospital cardiac arrest. The degree of color change correlates with the probability of ROSC.

  16. Serum levels of zinc and copper in epileptic children during long-term therapy with anticonvulsants.

    Science.gov (United States)

    Talat, Mohamed A; Ahmed, Anwar; Mohammed, Lamia

    2015-10-01

    To evaluate the serum levels of zinc and copper in epileptic children during the long-term treatment of anticonvulsant drugs and correlate this with healthy subjects. A hospital-based group matched case-control study was conducted in the Department of Pediatrics, Faculty of Medicine, Zagazig University, Zagazig, Egypt between November 2013 and October 2014. Ninety patients aged 7.1 ± 3.6 years were diagnosed with epilepsy by a neurologist. The control group was selected from healthy individuals and matched to the case group. Serum zinc and copper were measured by the calorimetric method using a colorimetric method kit. The mean zinc level was 60.1 ± 22.6 ug/dl in the cases, and 102.1 ± 18 ug/dl in the controls (p<0.001). The mean copper level was 180.1 ± 32.4 ug/dl in cases compared with 114.5 ± 18.5 ug/dl in controls (p<0.001). Serum zinc levels in epileptic children under drug treatment are lower compared with healthy children. Also, serum copper levels in these patients are significantly higher than in healthy people. No significant difference in the levels of serum copper and zinc was observed in using one drug or multiple drugs in the treatment of epileptic patients.

  17. Experiments on the radioimmunological determination of the triiodothyronine binding capacity of human blood serum

    International Nuclear Information System (INIS)

    Traub, H.W.J.

    1980-01-01

    Bovine serum antibodies have been obtained from rabbits. Constant amounts of antibodies have been incubated with increasing amounts of antigens. The maximum value found for T 3 binding to the antigen-antibody complex was 66 μg RA/mg antigen. Human serum samples containing 0,05 ng 125 J-T 3 /μl were incubated with 600 μg RA, and the antigen was precipitated with 8,4 mg anti-RA. The mean value obtained for 30 enthyreotic test persons was a binding to RA of 7.9 +- 0,52% 125 J-T 3 . Comparative measurements of patient and standard serum samples shared only slight differences. This means that the measured data do not reflect the thyroid function. (orig./MG) [de

  18. A colorimetric method for highly sensitive and accurate detection of iodide by finding the critical color in a color change process using silver triangular nanoplates

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiu-Hua; Ling, Jian, E-mail: lingjian@ynu.edu.cn; Peng, Jun; Cao, Qiu-E., E-mail: qecao@ynu.edu.cn; Ding, Zhong-Tao; Bian, Long-Chun

    2013-10-10

    Graphical abstract: -- Highlights: •Demonstrated a new colorimetric strategy for iodide detection by silver nanoplates. •The colorimetric strategy is to find the critical color in a color change process. •The colorimetric strategy is more accurate and sensitive than common colorimetry. •Discovered a new morphological transformation phenomenon of silver nanoplates. -- Abstract: In this contribution, we demonstrated a novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs). Very lower concentration of iodide can induce an appreciable color change of silver TNPs solution from blue to yellow by fusing of silver TNPs to nanoparticles, as confirmed by UV–vis absorption spectroscopy and transmission electron microscopy (TEM). The principle of this colorimetric assay is not an ordinary colorimetry, but a new colorimetric strategy by finding the critical color in a color change process. With this strategy, 0.1 μM of iodide can be recognized within 30 min by naked-eyes observation, and lower concentration of iodide down to 8.8 nM can be detected using a spectrophotometer. Furthermore, this high sensitive colorimetric assay has good accuracy, stability and reproducibility comparing with other ordinary colorimetry. We believe this new colorimetric method will open up a fresh insight of simple, rapid and reliable detection of iodide and can find its future application in the biochemical analysis or clinical diagnosis.

  19. A colorimetric method for highly sensitive and accurate detection of iodide by finding the critical color in a color change process using silver triangular nanoplates

    International Nuclear Information System (INIS)

    Yang, Xiu-Hua; Ling, Jian; Peng, Jun; Cao, Qiu-E.; Ding, Zhong-Tao; Bian, Long-Chun

    2013-01-01

    Graphical abstract: -- Highlights: •Demonstrated a new colorimetric strategy for iodide detection by silver nanoplates. •The colorimetric strategy is to find the critical color in a color change process. •The colorimetric strategy is more accurate and sensitive than common colorimetry. •Discovered a new morphological transformation phenomenon of silver nanoplates. -- Abstract: In this contribution, we demonstrated a novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs). Very lower concentration of iodide can induce an appreciable color change of silver TNPs solution from blue to yellow by fusing of silver TNPs to nanoparticles, as confirmed by UV–vis absorption spectroscopy and transmission electron microscopy (TEM). The principle of this colorimetric assay is not an ordinary colorimetry, but a new colorimetric strategy by finding the critical color in a color change process. With this strategy, 0.1 μM of iodide can be recognized within 30 min by naked-eyes observation, and lower concentration of iodide down to 8.8 nM can be detected using a spectrophotometer. Furthermore, this high sensitive colorimetric assay has good accuracy, stability and reproducibility comparing with other ordinary colorimetry. We believe this new colorimetric method will open up a fresh insight of simple, rapid and reliable detection of iodide and can find its future application in the biochemical analysis or clinical diagnosis

  20. Colorimetric sensor array for determination and identification of toxic industrial chemicals.

    Science.gov (United States)

    Feng, Liang; Musto, Christopher J; Kemling, Jonathan W; Lim, Sung H; Zhong, Wenxuan; Suslick, Kenneth S

    2010-11-15

    A low-cost yet highly sensitive colorimetric sensor array for the detection and identification of toxic industrial chemicals (TICs) has been developed. The sensor consists of a disposable array of cross-responsive nanoporous pigments whose colors are changed by diverse chemical interactions with analytes. Clear differentiation among 20 different TICs has been easily achieved at both their IDLH (immediately dangerous to life or health) concentration within 2 min of exposure and PEL (permissible exposure limit) concentration within 5 min of exposure with no errors or misclassifications. Detection limits are generally well below the PEL (in most cases below 5% of PEL) and are typically in the low ppb range. The colorimetric sensor array is not responsive to changes in humidity or temperature over a substantial range. The printed arrays show excellent batch to batch reproducibility and long shelf life (greater than 3 months).

  1. Immunoradiometric assay for ferritin in human serum

    International Nuclear Information System (INIS)

    Leyland, M.J.; Ganguli, P.C.; Blower, D.; Delamore, I.W.

    1975-01-01

    A sensitiv specific and precise immunoradiometric assay for ferritin has been developed. Ferritin was measured in the serum of 160 hospital controls, 101 females (118 plus/minus 9 μg/l) and 59 males (189 plus/minus 16 μg/l). This difference was statistically significant. In 28 patients with untreated iron deficiency anemia, serum ferritin concentration (6.1plus/minus 0.7 μg/l) was significantly lower than in the controls, but it was within the normal range in 14 cases of polycythaemia vera treated by repeated phlebotomy. In 4 patients with primary haemachromatosis (2884 plus/minus 56 μg/l), 25 with secondary iron overload states (5702 plus/minus 1235 μg/l) and 8 with haemolytic anaemia (1612 plus/minus 605 μg/l), serum ferritin levels were markedly elevated. In 14 cases of transfusional siderosis there was a highly significant correlation between serum ferritin concentration and units of blood transfused. A circadian rhythmin serum ferritin concentration was observed in 7 healthy subjects. (author)

  2. Evaluation of the binding effect of human serum albumin on the properties of granules.

    Science.gov (United States)

    Kristó, Katalin; Bajdik, János; Eros, István; Pintye-Hódi, Klára

    2008-11-01

    The main objective of this study was the application of a solution of human serum albumin as a granulating fluid. The properties of the granules formed were evaluated and compared with those when a conventional binder was applied in the same concentration. The powder mixture contained a soluble (mannitol) and an insoluble component (different types of cellulose). The protein solution applied exerted an appropriate aggregating effect if the system contained microcrystalline celluloses. Powdered cellulose was not suitable for the granulation with human serum albumin solution. As compared with the same concentration of the conventionally applied cellulose ethers as binder, the prepared granules exhibited a larger particle size, a significantly better compressibility, a higher breaking hardness and a favourable deformation process. These findings mainly reflect the good adhesive properties of the protein. The best compressibility and mechanical behaviour were attained on the application of the microcrystalline cellulose Vivapur type 105. This favourable behaviour may be connected with the wettability of cellulose. These results suggest that the formulation of tablets may be easier from an active agent in the serum that binds to albumin (e.g. interferon) since the amount of additives (binder) can be reduced.

  3. Microtiter plate based colorimetric assay for characterization of dehalogenation activity of GAC/Fe0 composite

    DEFF Research Database (Denmark)

    Hwang, Yuhoon; Salatas, Apostolos; Mines, Paul D.

    2015-01-01

    of nZVI and its composite with granular activated carbon (GAC). The assay focused on analysis of reaction products rather than its mother compounds, which gives more accurate quantification of reductive activity. The colorimetric assays were developed to quantify three reaction products, ammonia......Even though nanoscale zero valent iron (nZVI) has been intensively studied for the treatment of a plethora of pollutants through reductive reaction, a quantification of nZVI reactivity has not been standardized. Here, we developed series of colorimetric assays for determining reductive activity...

  4. Online immunocapture ICP-MS for the determination of the metalloprotein ceruloplasmin in human serum.

    Science.gov (United States)

    Bernevic, Bogdan; El-Khatib, Ahmed H; Jakubowski, Norbert; Weller, Michael G

    2018-04-02

    The human copper-protein ceruloplasmin (Cp) is the major copper-containing protein in the human body. The accurate determination of Cp is mandatory for the reliable diagnosis of several diseases. However, the analysis of Cp has proven to be difficult. The aim of our work was a proof of concept for the determination of a metalloprotein-based on online immunocapture ICP-MS. The immuno-affinity step is responsible for the enrichment and isolation of the analyte from serum, whereas the compound-independent quantitation with ICP-MS delivers the sensitivity, precision, and large dynamic range. Off-line ELISA (enzyme-linked immunosorbent assay) was used in parallel to confirm the elution profile of the analyte with a structure-selective method. The total protein elution was observed with the 32 S mass trace. The ICP-MS signals were normalized on a 59 Co signal. The human copper-protein Cp could be selectively determined. This was shown with pure Cp and with a sample of human serum. The good correlation with off-line ELISA shows that Cp could be captured and eluted selectively from the anti-Cp affinity column and subsequently determined by the copper signal of ICP-MS.

  5. Studies on the cytotoxicity of diamond nanoparticles against human cancer cells and lymphocytes.

    Science.gov (United States)

    Adach, Kinga; Fijalkowski, Mateusz; Gajek, Gabriela; Skolimowski, Janusz; Kontek, Renata; Blaszczyk, Alina

    2016-07-25

    Detonation nanodiamonds (DND) are a widely studied group of carbon nanomaterials. They have the ability to adsorb a variety of biomolecules and drugs onto their surfaces, and additionally their surfaces may be subjected to chemical functionalization by covalent bonds. We present a procedure for the purification and surface oxidation of diamond nanoparticles, which were then tested by spectroscopic analysis such as ATR-FTIR, Raman spectroscopy, and thermogravimetric analysis. We also examined the zeta potential of the tested material. Analysis of the cytotoxic effect of nanodiamonds against normal lymphocytes derived from human peripheral blood, the non-small cell lung cancer cell line (A549) and the human colorectal adenocarcinoma cell line (HT29) was performed using MTT colorimetric assay. Evaluation of cell viability was performed after 1-h and 24-h treatment with the tested nanoparticles applied at concentrations ranging from 1 μg/ml to 100 μg/ml. We found that the survival of the examined cells was strongly associated with the presence of serum proteins in the growth medium. The incubation of cells with nanodiamonds in the presence of serum did not exert a significant effect on cell survival, while the cell treatment in a serum-free medium resulted in a decrease in cell survival compared to the negative control. The role of purification and functionalization of nanodiamonds on their cytotoxicity was also demonstrated. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Serum metabolome biomarkers associate low-level environmental perfluorinated compound exposure with oxidative /nitrosative stress in humans.

    Science.gov (United States)

    Wang, Xiaofei; Liu, Liangpo; Zhang, Weibing; Zhang, Jie; Du, Xiaoyan; Huang, Qingyu; Tian, Meiping; Shen, Heqing

    2017-10-01

    Previous in vivo and in vitro studies have linked perfluorinated compound (PFC) exposure with metabolic interruption, but the inter-species difference and high treatment doses usually make the results difficult to be extrapolated to humans directly. The best strategy for identifying the metabolic interruption may be to establish the direct correlations between monitored PFCs data and metabolic data on human samples. In this study, serum metabolome data and PFC concentrations were acquired for a Chinese adult male cohort. The most abundant PFCs are PFOA and PFOS with concentration medians 7.56 and 12.78 nM, respectively; in together they count around 81.6% of the total PFCs. PFC concentration-related serum metabolic profile changes and the related metabolic biomarkers were explored by using partial least squares-discriminant analysis (PLS-DA). Respectively taking PFOS, PFOA and total PFC as the classifiers, serum metabolome can be differentiated between the lowest dose group (1st quartile PFCs) and the highest PFC dose group (4th quartile PFCs). Ten potential PFC biomarkers were identified, mainly involving in pollutant detoxification, antioxidation and nitric oxide (NO) signal pathways. These suggested that low-level environmental PFC exposure has significantly adverse impacts on glutathione (GSH) cycle, Krebs cycle, nitric oxide (NO) generation and purine oxidation in humans. To the best of our knowledge, this is the first report investigating the association of environmental PFC exposure with human serum metabolome alteration. Given the important biological functions of the identified biomarkers, we suggest that PFC could increase the metabolism syndromes risk including diabetes and cardiovascular diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Characterization of cryopreserved primary human corneal endothelial cells cultured in human serum-supplemented media

    Directory of Open Access Journals (Sweden)

    Lucas Monferrari Monteiro Vianna

    2016-02-01

    Full Text Available ABSTRACT Purpose: To compare cryopreserved human corneal endothelial cells (HCECs grown in human serum-supplemented media (HS-SM with cryopreserved HCECs grown in fetal bovine serum-supplemented media (FBS-SM. Methods: Three pairs of human corneas from donors aged 8, 28, and 31 years were obtained from the eye bank. From each pair, one cornea was used to start a HCEC culture using HS-SM; the other cornea was grown in FBS-SM. On reaching confluence, the six cell populations were frozen using 10% dimethyl sulfoxidecontaining medium. Thawed cells grown in HS-SM were compared with those grown in FBS-SM with respect to morphology, growth curves, immunohistochemistry, real time-reverse transcriptase polymerase chain reaction (RT-PCR for endothelial cell markers, and detachment time. Results: No difference in morphology was observed for cells grown in the two media before or after cryopreservation. By growth curves, cell counts after thawing were similar in both media, with a slight trend toward higher cell counts in FBS-SM. Cells grown in both the media demonstrated a similar expression of endothelial cell markers when assessed by immunohistochemistry, although HCEC marker gene expression was higher in cells grown in HS-SM than in those grown in FBS-SM as assessed by RT-PCR. With FBS-SM, there was a tendency of longer detachment time and lower cell passages. Conclusions: HS-SM was similar to FBS-SM for cryopreservation of cultured HCECs as assessed by analysis of cell morphology, proliferation, and protein expression, although marker gene expression was higher in cells grown in HS-SM than in those grown in FBS-SM. Detachment time was longer with FBS-SM and in lower passages.

  8. Biomolecular Interaction Study of Cyclolinopeptide A with Human Serum Albumin

    Directory of Open Access Journals (Sweden)

    Ben Rempel

    2010-01-01

    Full Text Available The kinetics, energetics, and structure of Cyclolinopeptide A binding with Human Serum Albumin were investigated with surface plasmon resonance and circular dichroism. The complex is formed through slow recognition kinetics that is temperature sensitive in the range of 20°C–37°C. The overall reaction was observed to be endothermic (ΔH=204 kJ mol−1 and entropy driven (ΔS=746 J mol−1K−1 with overall small changes to the tertiary structure.

  9. High-pressure liquid chromatographic assay of Bay n 7133 in human serum.

    OpenAIRE

    Fasching, C E; Hughes, C E; Hector, R F; Peterson, L R

    1984-01-01

    A high-pressure liquid chromatographic method that includes a Sep-Pak (Waters Associates, Inc., Milford , Mass.) preparation of human serum was employed for the quantitative assay of Bay n 7133. Drug levels of 0.1 to 20 micrograms/ml could be detected. No interference from amphotericin B was found in the chromatographic analysis of Bay n 7133.

  10. Relationship of serum and seminal plasma zinc levels and serum testosterone in oligospermic and azoospermic infertile men

    International Nuclear Information System (INIS)

    Ali, H.; Qasim, R.; Baig, M.; Rana, M.F.; Ali, M.; Khem, A.K.

    2005-01-01

    Objective: To measure the zinc level in fertile and infertile population and to find out relationship of serum and seminal plasma zinc levels and serum testosterone in oligospermic and azoospermic infertile men. Design: Comparative study. Place and Duration of Study: The Infertility Clinic, Jinnah Postgraduate Medical Center (JPMC), Karachi, from January 2002-July 2003. Patients and Methods: Fifty-eight primary infertile male subjects, without any treatment, who had regular unprotected intercourse for at least 12 months without conception with their partners, aged 20-40 years, having normal and regular menstrual cycles without any uterine pathology or hormonal disturbance were selected from Infertile Clinic, Jinnah Postgraduate Medical Center, Karachi. After semen analyses, they were grouped as, oligospermic (30), and azoospermic (28). Twenty-five known fertile male selected from general population (their spouse had given birth to a child within one year) and after semen analysis were taken as normospermic control group. Semen analyzed according to WHO criteria and serum and seminal plasma zinc was estimated by 5Br. PAPS colorimetric method. Serum testosterone, LH, and FSH were measured by ELISA, using kits supplied by Diagnostic System Laboratories (DSL), U.S.A. Results: The mean value for testosterone was significantly low in oligospermic, (8.04+0.76) and azoospermic subjects (7.14+0.27) as compared to normospermic (9.90+0.14) control groups (p<0.05, p<0.001 respectively), serum LH (p<0.05, p<0.001) respectively) and FSH (p<0.05) were significantly higher than normospermic control group. Serum and seminal plasma zinc levels was low in oligospermic, and azoospermic subjects when compared with normospermic control groups (p<0.05, p<0.001 respectively). This suggests its involvement in spermatogenesis and infertility in such patients. Seminal zinc level has weak correlation with testosterone in oligospermic (r=0.44, p<0.05) and with serum zinc in azoospermic

  11. Photoexcited riboflavin induces oxidative damage to human serum albumin

    Science.gov (United States)

    Hirakawa, Kazutaka; Yoshioka, Takuto

    2015-08-01

    Photoexcited riboflavin induced damage of human serum albumin (HSA), a water soluble protein, resulting in the diminishment of fluorescence from the tryptophan residue. Because riboflavin hardly photosensitized singlet oxygen generation and sodium azide, a singlet oxygen quencher, did not inhibit protein damage, electron transfer-mediated oxidation of HSA was speculated. Fluorescence lifetime of riboflavin was not affected by HSA, suggesting that the excited triplet state of riboflavin is responsible for protein damage through electron transfer. In addition, the preventive effect of xanthone derivatives, triplet quenchers, on photosensitized protein damage could be evaluated using this photosensitized reaction system of riboflavin and HSA.

  12. Receptor research on xenohormone effects of human serum extracts containing the actual mixture of perfluorinated alkyl acids: a short review

    DEFF Research Database (Denmark)

    Bjerregaard-Olesen, Christian; Bonefeld-Jørgensen, Eva Cecilie

    2015-01-01

    differs between individuals. Hence, the toxicological studies of single PFAAs and simple mixtures might be insufficient to predict how the actual mixtures of PFAAs may affect humans. To get a better evaluation of the actual mixture effects, we developed a method to extract the actual mixture of PFAAs from...... (http://fetotox.au.dk/), we are currently extracting the actual PFAA serum mixture from 700 pregnant women to further elucidate the potential of the serum PFAA mixture to transactivate the ER at the levels found in human serum. We suggest that our method can in the future be used to study the effects...... of the actual serum PFAA mixture on both steroid hormone actions as well as other hormonal systems e.g. thyroid hormone function. In the current review we will discuss how our recently developed PFAA extraction method might be used in future research to assess the endocrine impact of PFAAs on human health....

  13. Density and radioactivity distribution of respirable range human serum albumin aerosol

    International Nuclear Information System (INIS)

    Raghunath, B.; Somasundaram, S.; Soni, P.S.

    1988-01-01

    Dry human serum albumin (HSA) aerosol in the respirable size range was generated using the BARC nebulizer. The aerosol was sampled using Lovelace Aerosol Particle Separator (LAPS) and the density of HSA was determined. Labelling of HSA with 99m TcO 4 - was done, both in HSA solution and with dry denatured HSA particles, to study the distribution of radioactivity in both cases. The results are discussed. (author)

  14. MicroRNA-triggered, cascaded and catalytic self-assembly of functional ``DNAzyme ferris wheel'' nanostructures for highly sensitive colorimetric detection of cancer cells

    Science.gov (United States)

    Zhou, Wenjiao; Liang, Wenbin; Li, Xin; Chai, Yaqin; Yuan, Ruo; Xiang, Yun

    2015-05-01

    The construction of DNA nanostructures with various sizes and shapes has significantly advanced during the past three decades, yet the application of these DNA nanostructures for solving real problems is still in the early stage. On the basis of microRNA-triggered, catalytic self-assembly formation of the functional ``DNAzyme ferris wheel'' nanostructures, we show here a new signal amplification platform for highly sensitive, label-free and non-enzyme colorimetric detection of a small number of human prostate cancer cells. The microRNA (miR-141), which is catalytically recycled and reused, triggers isothermal self-assembly of a pre-designed, G-quadruplex sequence containing hairpin DNAs into ``DNAzyme ferris wheel''-like nanostructures (in association with hemin) with horseradish peroxidase mimicking activity. These DNAzyme nanostructures catalyze an intensified color transition of the probe solution for highly sensitive detection of miR-141 down to 0.5 pM with the naked eye, and the monitoring of as low as 283 human prostate cancer cells can also, theoretically, be achieved in a colorimetric approach. The work demonstrated here thus offers new opportunities for the construction of functional DNA nanostructures and for the application of these DNA nanostructures as an effective signal amplification means in the sensitive detection of nucleic acid biomarkers.

  15. A Colorimetric Sensor for Qualitative Discrimination and Quantitative Detection of Volatile Amines

    Directory of Open Access Journals (Sweden)

    Zhonglin Tang

    2010-06-01

    Full Text Available We have developed a novel colorimetric sensor based on a digital camera and white LED illumination. Colorimetric sensor arrays (CSAs were made from a set of six chemically responsive dyes impregnated on an inert substrate plate by solution casting. Six common amine aqueous solutions, including dimethylamine, triethylamine, diisopropyl-amine, aniline, cyclohexylamine, and pyridine vaporized at 25 °C and six health-related trimethylamine (TMA concentrations including 170 ppm, 51 ppm, 8 ppm, 2 ppm, 125 ppb and 50 ppb were analyzed by the sensor to test its ability for the qualitative discrimination and quantitative detection of volatile amines. We extracted the feature vectors of the CSA's response to the analytes from a fusional color space, which was obtained by conducting a joint search algorithm of sequential forward selection and sequential backward selection (SFS&SBS based on the linear discriminant criteria (LDC in a mixed color space composed of six common color spaces. The principle component analysis (PCA followed by the hierarchical cluser analysis (HCA were utilized to discriminate 12 analytes. Results showed that the colorimetric sensor grouped the six amine vapors and five TMA concentrations correctly, while TMA concentrations of 125 ppb and 50 ppb were indiscriminable from each other. The limitation of detection (LOD of the sensor for TMA was found to be lower than 50 ppb. The CSAs were reusable for TMA concentrations below 8 ppm.

  16. Paper-Plastic Hybrid Microfluidic Device for Smartphone-Based Colorimetric Analysis of Urine.

    Science.gov (United States)

    Jalal, Uddin M; Jin, Gyeong Jun; Shim, Joon S

    2017-12-19

    In this work, a disposable paper-plastic hybrid microfluidic lab-on-a-chip (LOC) has been developed and successfully applied for the colorimetric measurement of urine by the smartphone-based optical platform using a "UrineAnalysis" Android app. The developed device was cost-effectively implemented as a stand-alone hybrid LOC by incorporating the paper-based conventional reagent test strip inside the plastic-based LOC microchannel. The LOC device quantitatively investigated the small volume (40 μL) of urine analytes for the colorimetric reaction of glucose, protein, pH, and red blood cell (RBC) in integration with the finger-actuating micropump. On the basis of our experiments, the conventional urine strip showed large deviation as the reaction time goes by, because dipping the strip sensor in a bottle of urine could not control the reaction volume. By integrating the strip sensor in the LOC device for urine analysis, our device significantly improves the time-dependent inconstancy of the conventional dipstick-based urine strip, and the smartphone app used for image analysis enhances the visual assessment of the test strip, which is a major user concern for the colorimetric analysis in point-of-care (POC) applications. As a result, the user-friendly LOC, which is successfully implemented in a disposable format with the smartphone-based optical platform, may be applicable as an effective tool for rapid and qualitative POC urinalysis.

  17. Droplet-based microscale colorimetric biosensor for multiplexed DNA analysis via a graphene nanoprobe

    International Nuclear Information System (INIS)

    Xiang Xia; Luo Ming; Shi Liyang; Ji Xinghu; He Zhike

    2012-01-01

    Graphical abstract: With a microvalve manipulate technique combined with droplet platform, a microscale fluorescence-based colorimetric sensor for multiplexed DNA analysis is developed via a graphene nanoprobe. Highlights: ► A quantitative detection for multiplexed DNA is first realized on droplet platform. ► The DNA detection is relied on a simple fluorescence-based colorimetric method. ► GO is served as a quencher for two different DNA fluorescent probes. ► This present work provides a rapid, sensitive, visual and convenient detection tool for droplet biosensor. - Abstract: The development of simple and inexpensive DNA detection strategy is very significant for droplet-based microfluidic system. Here, a droplet-based biosensor for multiplexed DNA analysis is developed with a common imaging device by using fluorescence-based colorimetric method and a graphene nanoprobe. With the aid of droplet manipulation technique, droplet size adjustment, droplet fusion and droplet trap are realized accurately and precisely. Due to the high quenching efficiency of graphene oxide (GO), in the absence of target DNAs, the droplet containing two single-stranded DNA probes and GO shows dark color, in which the DNA probes are labeled carboxy fluorescein (FAM) and 6-carboxy-X-rhodamine (ROX), respectively. The droplet changes from dark to bright color when the DNA probes form double helix with the specific target DNAs leading to the dyes far away from GO. This colorimetric droplet biosensor exhibits a quantitative capability for simultaneous detection of two different target DNAs with the detection limits of 9.46 and 9.67 × 10 −8 M, respectively. It is also demonstrated that this biosensor platform can become a promising detection tool in high throughput applications with low consumption of reagents. Moreover, the incorporation of graphene nanoprobe and droplet technique can drive the biosensor field one more step to some extent.

  18. Colorimetric detection of endogenous hydrogen sulfide production in living cells

    Science.gov (United States)

    Ahn, Yong Jin; Lee, Young Ju; Lee, Jaemyeon; Lee, Doyeon; Park, Hun-Kuk; Lee, Gi-Ja

    2017-04-01

    Hydrogen sulfide (H2S) has received great attention as a third gaseous signal transmitter, following nitric oxide and carbon monoxide. In particular, H2S plays an important role in the regulation of cancer cell biology. Therefore, the detection of endogenous H2S concentrations within biological systems can be helpful to understand the role of gasotransmitters in pathophysiology. Although a simple and inexpensive method for the detection of H2S has been developed, its direct and precise measurement in living cells remains a challenge. In this study, we introduced a simple, facile, and inexpensive colorimetric system for selective H2S detection in living cells using a silver-embedded Nafion/polyvinylpyrrolidone (PVP) membrane. This membrane could be easily applied onto a polystyrene microplate cover. First, we optimized the composition of the coating membrane, such as the PVP/Nafion mixing ratio and AgNO3 concentration, as well as the pH of the Na2S (H2S donor) solution and the reaction time. Next, the in vitro performance of a colorimetric detection assay utilizing the silver/Nafion/PVP membrane was evaluated utilizing a known concentration of Na2S standard solution both at room temperature and at 37 °C in a 5% CO2 incubator. As a result, the sensitivity of the colorimetric assay for H2S at 37 °C in the incubator (0.0056 Abs./μM Na2S, R2 = 0.9948) was similar to that at room temperature (0.0055 Abs./μM Na2S, R2 = 0.9967). Moreover, these assays were less sensitive to interference from compounds such as glutathione, L-cysteine (Cys), and dithiothreitol than to the H2S from Na2S. This assay based on the silver/Nafion/PVP membrane also showed excellent reproducibility (2.8% RSD). Finally, we successfully measured the endogenous H2S concentrations in live C6 glioma cells by s-(5‧-adenosyl)-L-methionine stimulation with and without Cys and L-homocysteine, utilizing the silver/Nafion/PVP membrane. In summary, colorimetric assays using silver

  19. Direct microcomputer controlled determination of zinc in human serum by flow injection atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Nielsen, Bent; Jensen, Arne

    1986-01-01

    A procedure is described for the direct determination of zinc in human serum by fully automated, microcomputer controlled flow injection atomic absorption spectrometry (Fl-AAS). The Fl system is pumpless, using the negative pressure created by the nebuliser. It only consists of a three-way valve......, programmable from the microcomputer, to control the sample volume. No pre-treatment of the samples is necessary. The limit of detection is 0.14 mg l–1, and only small amounts of serum (

  20. In vitro cellular adaptations of indicators of longevity in response to treatment with serum collected from humans on calorie restricted diets.

    Directory of Open Access Journals (Sweden)

    Joanne S Allard

    2008-09-01

    Full Text Available Calorie restriction (CR produces several health benefits and increases lifespan in many species. Studies suggest that alternate-day fasting (ADF and exercise can also provide these benefits. Whether CR results in lifespan extension in humans is not known and a direct investigation is not feasible. However, phenotypes observed in CR animals when compared to ad libitum fed (AL animals, including increased stress resistance and changes in protein expression, can be simulated in cells cultured with media supplemented with blood serum from CR and AL animals. Two pilot studies were undertaken to examine the effects of ADF and CR on indicators of health and longevity in humans. In this study, we used sera collected from those studies to culture human hepatoma cells and assessed the effects on growth, stress resistance and gene expression. Cells cultured in serum collected at the end of the dieting period were compared to cells cultured in serum collected at baseline (before the dieting period. Cells cultured in serum from ADF participants, showed a 20% increase in Sirt1 protein which correlated with reduced triglyceride levels. ADF serum also induced a 9% decrease in proliferation and a 25% increase in heat resistance. Cells cultured in serum from CR participants induced an increase in Sirt1 protein levels by 17% and a 30% increase in PGC-1alpha mRNA levels. This first in vitro study utilizing human serum to examine effects on markers of health and longevity in cultured cells resulted in increased stress resistance and an up-regulation of genes proposed to be indicators of increased longevity. The use of this in vitro technique may be helpful for predicting the potential of CR, ADF and other dietary manipulations to affect markers of longevity in humans.

  1. Effect of the conditions of isolation on the physicochemical properties of human serum albumin in the norm and with pathology

    Science.gov (United States)

    Ivanov, A. I.; Zhbankov, R. G.; Korolenko, E. A.; Korolik, E. V.; Meleshchenko, L. A.; Sarnatskaya, V. V.; Nikolaev, V. G.; Nikolaichik, V. V.; Yushko, L. A.

    1997-01-01

    Differential scanning calorimetry and IR spectrosocopy were used to investigate the effect of the procedure of isolation of human serum albumin on its physicochemical characteristics. It is shown that fractionation of blood plasma with ethylene glycol followed by ion exchange chromatography can be used to obtain albumin of normal donors that is similar to the albumin in the nonfractionated plasma according to melting thermograms. Endotherms of human serum albumin samples that were obtained by affinity chromatography and preparative electrophoresis are bimodal, unlike the monophasic for albumin obtained by polyethylene glycol precipitation. These changes result from a higher content of nonetherified fatty acids in the albumin samples obtained by affinity chromatography and from modification of the secondary protein structure in the samples obtained by electrophoresis. Analysis of melting thermograms of serum albumin from patients with uremia, chronic hepatitis, and peritonitis shows that fractionation of blood with polyethylene glycol preserves the thermodynamic characteristics of the various pathological serum albumins to the greatest extent. The present results demonstrate the advantage of polyethylene glycol fractionation for isolation of native preparations of normal and “pathological” human serum albumin.

  2. Aloe vera is non-toxic to cells: A microculture tetrazolium technique colorimetric assay study

    Directory of Open Access Journals (Sweden)

    Devi Gopakumar

    2014-01-01

    Full Text Available Introduction: Aloe vera (Av, a succulent of Liliaceae family is now a widely used medicinal plant. Its′ application covers a wide spectrum of human diseases, including oral mucosa, gastric mucosa and skin. Aloe vera preparations in the form of gel, mouth washes and cream are applied topically for many oral diseases. The applications include oral lichen planus, candidiasis, oral submucous fibrosis, geographic tongue, etc. Aims and Objectives: To evaluate the cytotoxicity of Av on human fibroblasts. Materials and Methods: Aloe vera preparation (70% was applied on the fibroblast cell lineage and the cell viability was evaluated by microculture tetrazolium technique (MTT colorimetric assay. Results: The cell viability at different concentrations was measured. The cells have maintained their viability at different concentrations used in the study. Conclusion: Our study shows the cell viability at different sample concentrations of Av. This could open up wide clinical applications of Av for reactive, inflammatory and potentially malignant oral and other mucocutaneous diseases.

  3. Systems analysis of singly and multiply O-glycosylated peptides in the human serum glycoproteome via EThcD and HCD mass spectrometry.

    Science.gov (United States)

    Zhang, Yong; Xie, Xinfang; Zhao, Xinyuan; Tian, Fang; Lv, Jicheng; Ying, Wantao; Qian, Xiaohong

    2018-01-06

    Human serum has been intensively studied to identify biomarkers via global proteomic analysis. The altered O-glycoproteome is associated with human pathological state including cancer, inflammatory and degenerative diseases and is an attractive source of disease biomarkers. Because of the microheterogeneity and macroheterogeneity of O-glycosylation, site-specific O-glycosylation analysis in human serum is still challenging. Here, we developed a systematic strategy that combined multiple enzyme digestion, multidimensional separation for sample preparation and high-resolution tandem MS with Byonic software for intact O-glycopeptide characterization. We demonstrated that multiple enzyme digestion or multidimensional separation can make sample preparation more efficient and that EThcD is not only suitable for the identification of singly O-glycosylated peptides (50.3%) but also doubly (21.2%) and triply (28.5%) O-glycosylated peptides. Totally, with the strict scoring criteria, 499 non-redundant intact O-glycopeptides, 173 O-glycosylation sites and 6 types of O-glycans originating from 49 O-glycoprotein groups were identified in human serum, including 121 novel O-glycosylation sites. Currently, this is the largest data set of site-specific native O-glycoproteome from human serum samples. We expect that the strategies developed by this study will facilitate in-depth analyses of native O-glycoproteomes in human serum and provide opportunities to understand the functional roles of protein O-glycosylation in human health and diseases. The altered O-glycoproteome is associated with human pathological state and is an attractive source of disease biomarkers. However, site-specific O-glycosylation analysis is challenging because of the microheterogeneity (different glycoforms attached to one glycosylation site) and macroheterogeneity (site occupancy) of O-glycosylation. In this work, we developed a systematic strategy for intact O-glycopeptide characterization. This study took

  4. Palmitate and stearate binding to human serum albumin. Determination of relative binding constants

    DEFF Research Database (Denmark)

    Vorum, H; Fisker, K; Honoré, B

    1997-01-01

    Multiple binding equilibria of two apparently insoluble ligands, palmitate and stearate, to defatted human serum albumin were studied in a 66 mM sodium phosphate buffer (pH 7.4) at 37 degrees C, by determination of dialytic exchange rates of ligands among identical equilibrium solutions. The expe...

  5. Carbon dots based immunosorbent assay for the determination of GFAP in human serum

    Science.gov (United States)

    Ma, Yunsu; Xu, Guanhong; Wei, Fangdi; Cen, Yao; Song, Yueyue; Ma, Yujie; Xu, Xiaoman; Shi, Menglan; Sohail, Muhammad; Hu, Qin

    2018-04-01

    Glial fibrillary acidic protein (GFAP) is expressed in the central nervous system and the level of GFAP normally rises with brain injury and astroglial tumors. So, serum GFAP is used as a marker for diagnosing various types of brain damage and astroglial tumors. In this study, a new sensor based on carbon dots (CDs) linked with antibodies to specifically detect GFAP in human serum was developed. Anti-GFAP (Ab1) linked with protein A/G agarose resin (PA/G) as a capture antibody (PA/G-Ab1) and anti-GFAP (Ab2) labeled with CDs as a detection antibody (CDs-Ab2) were prepared firstly. Then the CD-linked antibody immunosorbent assay (CLAISA) method was constructed based on the sandwich conjunction reaction among PA/G-Ab1, GFAP, and CDs-Ab2. CLAISA, using the fluorescence of PA/G-Ab1-GFAP-Ab2-CDs as the direct signal, enabled the proposed immunosensor to detect GFAP sensitively with a linear range of 0.10-8.00 ng ml-1 and a detection limit of 25 pg ml-1. This method was applied to the determination of GFAP in human serum by the standard addition method, and the results showed high accuracy and precision. Considering the easy synthetic process and excellent performance of CLAISA, this method has great potential to be used to monitor GFAP in the clinic.

  6. Exploiting pH-Regulated Dimer-Tetramer Transformation of Concanavalin A to Develop Colorimetric Biosensing of Bacteria.

    Science.gov (United States)

    Xu, Xiahong; Yuan, Yuwei; Hu, Guixian; Wang, Xiangyun; Qi, Peipei; Wang, Zhiwei; Wang, Qiang; Wang, Xinquan; Fu, Yingchun; Li, Yanbin; Yang, Hua

    2017-05-03

    Gold nanoparticles (AuNPs) aggregation-based colorimetric biosensing remains a challenge for bacteria due to their large size. Here we propose a novel colorimetric biosensor for rapid detection of Escherichia coli O157:H7 (E. coli O157:H7) in milk samples based on pH-regulated transformation of dimer/tetramer of Concanavalin A (Con A) and the Con A-glycosyl recognition. Briefly, antibody-modified magnetic nanoparticles was used to capture and concentrate E. coli O157:H7 and then to label with Con A; pH adjusted to 5 was then applied to dissociate Con A tetramer to release dimer, which was collected and re-formed tetramer at pH of 7 to cause the aggregation of dextran-modified AuNPs. The interesting pH-dependent conformation-transformation behavior of Con A innovated the design of the release from the bacteria surface and then the reconstruction of Con A. Therefore, we realized the sensitive colorimetric biosensing of bacteria, which are much larger than AuNPs that is generally not suitable for this kind of method. The proposed biosensor exhibited a limit of detection down to 41 CFU/mL, short assay time (~95 min) and satisfactory specificity. The biosensor also worked well for the detection in milk sample, and may provide a universal concept for the design of colorimetric biosensors for bacteria and virus.

  7. Design, Certification, and Deployment of the Colorimetric Water Quality Monitoring Kit (CWQMK)

    Science.gov (United States)

    Gazda, Daniel B.; Nolan, Daniel J.; Rutz, Jeff A.; Schultz, John R.; Siperko, Lorraine M.; Porter, Marc D.; Lipert, Robert J.; Flint, Stephanie M.; McCoy, J. Torin

    2010-01-01

    In August 2009, an experimental water quality monitoring kit based on Colorimetric Solid Phase Extraction (CSPE) technology was delivered to the International Space Station (ISS) aboard STS-128/17A. The kit, called the Colorimetric Water Quality Monitoring Kit (CWQMK), was flown and deployed as a Station Development Test Objective (SDTO) experiment on the ISS. The goal of the SDTO experiment is to evaluate the acceptability of CSPE technology for routine water quality monitoring on the ISS. This paper provides an overview of the SDTO experiment, as well as a detailed description of the CWQMK hardware and a summary of the testing and analysis conducted to certify the CWQMK for use on the ISS. The initial results obtained from the SDTO experiment are also reported and discussed in detail

  8. A gold nanoparticles-based colorimetric test to detect single nucleotide polymorphisms for improvement of personalized therapy of psoriasis

    Science.gov (United States)

    Marsella, Alessandra; Valentini, Paola; Tarantino, Paolo; Congedo, Maurizio; Pompa, Pier Paolo

    2016-04-01

    We report a simple, rapid and low-cost test, based on gold nanoparticles, for the naked-eye colorimetric detection of a signature of single nucleotide polymorphisms (SNPs) relevant for the personalized medicine of psoriasis patients. We validated the colorimetric assay on real-world DNA samples from a cohort of 30 psoriasis patients and we compared the results, in double-blind, with those obtained with two state-of-the-art instrumental techniques, namely reverse dot blotting and direct sequencing, finding 100% agreement. We demonstrated high accuracy, sensitivity and specificity of the colorimetric test that can be easily adapted for the genotypization of different SNPs, important for the pharmacogenomics of various diseases, and in other fields, such as food traceability and population structure analysis.

  9. Spectro colorimetric and GC-MS Models, Used to Determine the Changes in the Natural Compounds of the Sea Buck thorn Leaves Sterilized with Ionizing Radiations

    International Nuclear Information System (INIS)

    Minea, R.; Popescu, M.I.; Sima, E.; Dumitrascu, M.; Culea, M.; Manea, St.; Mazilu, E.

    2009-01-01

    Spectro colorimetric and GC-MS methods were developed for the quantitative and quality analyze of the fatty acid methyl esters (FAME) and of some natural compounds extracted from the Sea Buckthorn (Hippophae rhamnoides) leaves sterilized by treating them with accelerated electron beams, generated by a linear accelerator. The spectro colorimetric models describe and easy controls the color as it relies on the psycho physics of the color perception and on the simple colorimetric models. Hunter Lab, CIELAB, CIELCH simple colorimetric models are used in developing complex colorimetric models and for the calculation of simple colorimetric models expressed as the total color difference between a sample and a witness, ΔΕ * , ΔΕ C MC, ΔΕ * D IN99, ΔΕ * C IE2000. They provide qualitative data on the deterioration of the active compounds by irradiation. If they are validated by GC-MS methods, they can also provide quantitative data on the radioinduced changes caused to the Sea Buckthorn leaves. The developed GC-MS methods allow the validation of the spectro colorimetric methods for the quantitative and qualitative evaluation of the radioinduced changes in the Sea Buckthorn leaves, reducing both the analyze times and the analyze cost, respectively the random errors of the procedures for extraction and derivation applied to samples preparation

  10. Colorimetric tests for diagnosis of filarial infection and vector surveillance using non-instrumented nucleic acid loop-mediated isothermal amplification (NINA-LAMP.

    Directory of Open Access Journals (Sweden)

    Catherine B Poole

    Full Text Available Accurate detection of filarial parasites in humans is essential for the implementation and evaluation of mass drug administration programs to control onchocerciasis and lymphatic filariasis. Determining the infection levels in vector populations is also important for assessing transmission, deciding when drug treatments may be terminated and for monitoring recrudescence. Immunological methods to detect infection in humans are available, however, cross-reactivity issues have been reported. Nucleic acid-based molecular assays offer high levels of specificity and sensitivity, and can be used to detect infection in both humans and vectors. In this study we developed loop-mediated isothermal amplification (LAMP tests to detect three different filarial DNAs in human and insect samples using pH sensitive dyes for enhanced visual detection of amplification. Furthermore, reactions were performed in a portable, non-instrumented nucleic acid amplification (NINA device that provides a stable heat source for LAMP. The efficacy of several strand displacing DNA polymerases were evaluated in combination with neutral red or phenol red dyes. Colorimetric NINA-LAMP assays targeting Brugia Hha I repeat, Onchocerca volvulus GST1a and Wuchereria bancrofti LDR each exhibit species-specificity and are also highly sensitive, detecting DNA equivalent to 1/10-1/5000th of one microfilaria. Reaction times varied depending on whether a single copy gene (70 minutes, O. volvulus or repetitive DNA (40 min, B. malayi and W. bancrofti was employed as a biomarker. The NINA heater can be used to detect multiple infections simultaneously. The accuracy, simplicity and versatility of the technology suggests that colorimetric NINA-LAMP assays are ideally suited for monitoring the success of filariasis control programs.

  11. On the radiolysis of desoxyribonucleic acid in presence of serum albumin

    International Nuclear Information System (INIS)

    Geiger, A.M.

    1984-01-01

    The experiments were carried out on the simple model of DNA-bovine serum albumin. The two substances were solved in 10 -2 M sodium phosphate buffer pH 7 in the ratio 1 : 10, which is about the natural ratio of nucleic acid to protein in the cell. The preparations were irradiated with various doses up to 1760 Gy, in the presence of air, nitrogen, or laughing gas. The irradiated samples were then separated over the gel sepharose CL-2B using 2 x 10 -2 M sodium phosphate buffer pH 7 with and without sodium dodecyl sulphate. Photometric measurement of the fractions was done using a wavelength of 260 nm. The protein content was determined with two different colorimetric techniques, after calibrating experiments defining the linear range. In order to determine the effect of the protein on the radiosensitivity of the DNA, samples without bovine serum albumin were irradiated in the three gaseous environments with 440 Gy. Incubation of the irradiated samples with SDS, and separation in the presence of SDS, revealed information on the covalent bonds forming between DNA and bovine serum albumin, whereas gel filtration without SDS yielded information also on non-covalent bonds. (orig./EF) [de

  12. Visual and colorimetric methods for rapid determination of total tannins in vegetable raw materials

    Directory of Open Access Journals (Sweden)

    S. P. Kalinkina

    2016-01-01

    Full Text Available The article is dedicated to the development of rapid colorimetric method for determining the amount of tannins in aqueous extracts of vegetable raw materials. The sorption-based colorimetric test is determining sorption tannins polyurethane foam, impregnated of FeCl3, receiving on its surface painted in black and green color of the reaction products and the determination of their in sorbent matrix. Selectivity is achieved by determining the tannins specific interaction of polyphenols with iron ions (III. The conditions of sorption-colorimetric method: the concentration of ferric chloride (III, impregnated in the polyurethane foam; sorbent mass in the analytical cartridge; degree of loading his agent; the contact time of the phases. color scales have been developed for the visual determination of the amount of tannins in terms of gallic acid. Spend a digitized image obtained scales using computer program “Sorbfil TLC”, excluding a subjective assessment of the intensity of the color scale of the test. The results obtained determine the amount of tannins in aqueous extracts of vegetable raw rapid method using tablets and analytical cartridges. The results of the test determination of tannins with visual and densitometric analytical signal registration are compared to known methods. Spend a metrological evaluation of the results of determining the amount of tannins sorption rapid colorimetric methods. Time visual and densitometric rapid determination of tannins, taking into account the sample preparation is 25–30 minutes, the relative error does not exceed 28 %. The developed test methods for quantifying the content of tannins allow to exclude the use of sophisticated analytical equipment, carry out the analysis in non-laboratory conditions do not require highly skilled personnel.

  13. Rapid colorimetric detection of Zika virus from serum and urine specimens by reverse transcription loop-mediated isothermal amplification (RT-LAMP.

    Directory of Open Access Journals (Sweden)

    Amanda E Calvert

    Full Text Available Zika virus (ZIKV has emerged as a major global public health concern in the last two years due to its link as a causative agent of human birth defects. Its rapid expansion into the Western Hemisphere as well as the ability to be transmitted from mother to fetus, through sexual transmission and possibly through blood transfusions has increased the need for a rapid and expansive public health response to this unprecedented epidemic. A non-invasive and rapid ZIKV diagnostic screening assay that can be performed in a clinical setting throughout pregnancy is vital for prenatal care of women living in areas of the world where exposure to the virus is possible. To meet this need we have developed a sensitive and specific reverse transcriptase loop-mediated isothermal amplification (RT-LAMP assay to detect ZIKV RNA in urine and serum with a simple visual detection. RT-LAMP results were shown to have a limit of detection 10-fold higher than qRT-PCR. As little as 1.2 RNA copies/μl was detected by RT-LAMP from a panel of 178 diagnostic specimens. The assay was shown to be highly specific for ZIKV RNA when tested with diagnostic specimens positive for dengue virus (DENV and chikungunya virus (CHIKV. The assay described here illustrates the potential for a fast, reliable, sensitive and specific assay for the detection of ZIKV from urine or serum that can be performed in a clinical or field setting with minimal equipment and technological expertise.

  14. Application of human erythrocytes to a radioimmune assay of immune complexes in serum. [Lupus erythematosus, type B hepatitis

    Energy Technology Data Exchange (ETDEWEB)

    Tsuda, F; Miyakawa, Y; Mayumi, M [Tokyo Metropolitan Lab. of Public Health (Japan)

    1979-07-01

    An immune adherence receptor exists on the surface of primate erythrocytes, and has been characterized as a receptor for the activated third component of complement (C3b). Human red blood cells (RCBs, blood group O) were applied to a sensitive determination of complement-fixing, soluble immune complexes in serum. The method involved the binding of immune complexes with RBCs in the presence of complement and the detection of cell-bound IgG molecules by radiolabelled anti-human IgG antibodies. Since the binding of RBCs with monomeric IgG was minimal, cell bound IgG molecules were taken as representing immune complexes. When aggregated human gammaglobulin (AHG) was used as a model of immune complexes, as little as 5 ..mu..g dissolved in 1 ml of normal human serum were detected. The binding of RBCs with AHG was inhibited in EDTA solution where the classical complement pathway could not be activated. The RBC radioimmune assay was successfully applied to the determination of soluble immune complexes in pathological serum samples obtained from the patients with systemic lupus erythematosus and those with fulminant Type B hepatitis. False-positive results by autoantibodies against RBCs could be excluded by a Coombs test and by comparing the binding in the presence of complement with that in EDTA solution. The ubiquitous availability of RBCs coupled with a high sensitivity would allow the RBC radioimmune assay to be used as a further method of determining immune complexes in the serum.

  15. 2 development of a simple amino-modified silica-based colorimetric

    African Journals Online (AJOL)

    Temechegn

    with the increase in detection times as the concentration of the ions decreased. ..... New York: Clear Thinking Communications. 2010. ... W.S. Harwood and M.M. McMahon, Effects of integrated video media on student achievement ... Q. Lin, P. Chen, J. Liu, Y. Fu, Y. Zhang and T. Wei, Colorimetric chemosensor and test kit for.

  16. Molecular Structure-Affinity Relationship of Flavonoids in Lotus Leaf (Nelumbo nucifera Gaertn.) on Binding to Human Serum Albumin and Bovine Serum Albumin by Spectroscopic Method.

    Science.gov (United States)

    Tang, Xiaosheng; Tang, Ping; Liu, Liangliang

    2017-06-23

    Lotus leaf has gained growing popularity as an ingredient in herbal formulations due to its various activities. As main functional components of lotus leaf, the difference in structure of flavonoids affected their binding properties and activities. In this paper, the existence of 11 flavonoids in lotus leaf extract was confirmed by High Performance Liquid Chromatography (HPLC) analysis and 11 flavonoids showed various contents in lotus leaf. The interactions between lotus leaf extract and two kinds of serum albumins (human serum albumin (HSA) and bovine serum albumin (BSA)) were investigated by spectroscopic methods. Based on the fluorescence quenching, the interactions between these flavonoids and serum albumins were further checked in detail. The relationship between the molecular properties of flavonoids and their affinities for serum albumins were analyzed and compared. The hydroxylation on 3 and 3' position increased the affinities for serum albumins. Moreover, both of the methylation on 3' position of quercetin and the C₂=C₃ double bond of apigenin and quercetin decreased the affinities for HSA and BSA. The glycosylation lowered the affinities for HSA and BSA depending on the type of sugar moiety. It revealed that the hydrogen bond force played an important role in binding flavonoids to HSA and BSA.

  17. In vitro preliminary cytotoxicity testing of vegetal extracts, using colorimetric methods

    Directory of Open Access Journals (Sweden)

    Claudia Patricia Cordero Camacho

    2002-01-01

    Full Text Available To advance in the study of the Colombian vegetal biodiversity, considered as a potential source of pharmacologically active products, the establishment of biological activity evaluation systems is necessary, which allow the detection of active products against pathologies with high social and economical impact, such as cancer. This work describes the implementation of a preliminary in vitro methodology for the determination of potential anticancer activity in vegetal extracts, by cytotoxicity testing upon human tumor cell lines, measuring the cellular mass indirectly with the colorimetric assays of MTT (methyl tetrazolium tiazole reduction and SRB (sulforhodamine Bstaining. HT-29, MCF-7, SiHa and HEp-2 cell lines cultures were adapted, MTT concentration, cellular density and treatment period parameters for the cytotoxicity assay were selected. Cell lines sensitivity to the chemotherapeutic agent Doxorubicin HCl was determined. Colombian vegetal species extracts cytotoxicity was tested and usefulness of the assay as a tool to bioguide the search of active products was evidenced.

  18. In vitro preliminary cytotoxicity testing of vegetal extracts, using colorimetric methods

    Directory of Open Access Journals (Sweden)

    Claudia Patricia Cordero Camacho

    2011-12-01

    Full Text Available To advance in the study of the Colombian vegetal biodiversity, considered as a potential source of pharmacologically active products, the establishment of biological activity evaluation systems is necessary, which allow the detection of active products against pathologies with high social and economical impact, such as cancer. This work describes the implementation of a preliminary in vitro methodology for the determination of potential anticancer activity in vegetal extracts, by cytotoxicity testing upon human tumor cell lines, measuring the cellular mass indirectly with the colorimetric assays of MTT (methyl tetrazolium tiazole reduction and SRB (sulforhodamine Bstaining. HT-29, MCF-7, SiHa and HEp-2 cell lines cultures were adapted, MTT concentration, cellular density and treatment period parameters for the cytotoxicity assay were selected. Cell lines sensitivity to the chemotherapeutic agent Doxorubicin HCl was determined. Colombian vegetal species extracts cytotoxicity was tested and usefulness of the assay as a tool to bioguide the search of active products was evidenced.

  19. Virtual colorimetric sensor array: single ionic liquid for solvent discrimination.

    Science.gov (United States)

    Galpothdeniya, Waduge Indika S; Regmi, Bishnu P; McCarter, Kevin S; de Rooy, Sergio L; Siraj, Noureen; Warner, Isiah M

    2015-04-21

    There is a continuing need to develop high-performance sensors for monitoring organic solvents, primarily due to the environmental impact of such compounds. In this regard, colorimetric sensors have been a subject of intense research for such applications. Herein, we report a unique virtual colorimetric sensor array based on a single ionic liquid (IL) for accurate detection and identification of similar organic solvents and mixtures of such solvents. In this study, we employ eight alcohols and seven binary mixtures of ethanol and methanol as analytes to provide a stringent test for assessing the capabilities of this array. The UV-visible spectra of alcoholic solutions of the IL used in this study show two absorption bands. Interestingly, the ratio of absorbance for these two bands is found to be extremely sensitive to alcohol polarity. A virtual sensor array is created by using four different concentrations of IL sensor, which allowed identification of these analytes with 96.4-100% accuracy. Overall, this virtual sensor array is found to be very promising for discrimination of closely related organic solvents.

  20. Labeling of human serum albumin with 105Rh-cysteine complexes

    International Nuclear Information System (INIS)

    Lo, J.M.; Pillai, M.R.A.; John, C.S.; Troutner, D.E.

    1990-01-01

    The conjugation of a complex formed by reacting RhCl 3 with cysteine to human serum albumin has been investigated. Approximately 50% of the rhodium (labelled with 105 Rh) was converted to the complex. Conjugation of the complex to HSA via the ECDI method resulted in yields of ∼ 40% of the total rhodium or ∼ 80% of the Rh-cysteine complex. No conjugation was observed in the absence of the ECDI. At approximately equal molar concentrations of rhodium and HSA, an average of ∼ 0.4 rhodium atoms per HSA molecule was achieved. (author)

  1. Development of a novel colorimetric sensor based on alginate beads for monitoring rainbow trout spoilage.

    Science.gov (United States)

    Majdinasab, Marjan; Hosseini, Seyed Mohammad Hashem; Sepidname, Marziyeh; Negahdarifar, Manizheh; Li, Peiwu

    2018-05-01

    Alginate is a non-toxic, renewable, and linear copolymer obtained from the brown algae Laminaria digitata that can be easily shaped into beads. Its good gel forming properties have made it useful for entrapping food and pharmaceutical ingredients. In this study, alginate beads were used in a novel application as a colorimetric sensor in food intelligent packaging. Colorimetric sensor was developed through entrapping red cabbage extract as a pH indicator in alginate beads. The pH indicator beads were used in rainbow trout packaging for monitoring fillets spoilage. Color change of beads during fish storage was measured using the CIELab method. The alginate bead colorimetric sensor is validated by measuring total volatile basic nitrogen (TVB-N) levels and microbial populations in fish samples. Moreover, peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) were evaluated during storage. Results indicated that increasing the bacterial population during storage and production of proteolytic enzymes resulted in protein degradation, accumulation of volatile amine compounds, increase in the pH and finally color change of alginate beads. The values of TVB-N, pH, PV and TBARS increased with time of storage. The results of TVB-N and microbial growth were in accordance with color change of beads and CIELab data. Therefore, the proposed system enjoys a high sensitivity to pH variations and is capable of monitoring the spoilage of fish or other protein-rich products through its wide range of color changes. The alginate beads containing the red cabbage extract can, thus, be used as a low-cost colorimetric sensor for intelligent packaging applications.

  2. Fluorescence lifetime measurements of native and glycated human serum albumin and bovine serum albumin

    Science.gov (United States)

    Joshi, Narahari V.; Joshi, Virgina O. d.; Contreras, Silvia; Gil, Herminia; Medina, Honorio; Siemiarczuk, Aleksander

    1999-05-01

    Nonenzymatic glycation, also known as Maillard reaction, plays an important role in the secondary complications of the diabetic pathology and aging, therefore, human serum albumin (HSA) and bovine serum albumin (BSA) were glycated by a conventional method in our laboratory using glucose as the glycating agent. Fluorescence lifetime measurements were carried out with a laser strobe fluorometer equipped with a nitrogen/dye laser and a frequency doubler as a pulsed excitation source. The samples were excited at 295 nm and the emission spectra were recorded at 345 nm. The obtained decay curves were tried for double and triple exponential functions. It has been found that the shorter lifetime increases for glycated proteins as compared with that of the native ones. For example, in the case of glycated BSA the lifetime increased from 1.36 ns to 2.30 ns. Similarly, for HSA, the lifetime increases from 1.58 ns to 2.26 ns. Meanwhile, the longer lifetime changed very slightly for both proteins (from 6.52 ns to 6.72 ns). The increase in the lifetime can be associated with the environmental effect; originated from the attachment of glucose to some lysine residues. A good example is Trp 214 which is in the cage of Lys 225, Lys 212, Lys 233, Lys 205, Lys 500, Lys 199 and Lys 195. If fluorescence lifetime technique is calibrated and properly used it could be employed for assessing glycation of proteins.

  3. Sensitive colorimetric assay for uric acid and glucose detection based on multilayer-modified paper with smartphone as signal readout.

    Science.gov (United States)

    Wang, Xu; Li, Fang; Cai, Ziqi; Liu, Kaifan; Li, Jing; Zhang, Boyang; He, Jianbo

    2018-04-01

    In this work, a multilayer-modified paper-based colorimetric sensing platform with improved color uniformity and intensity was developed for the sensitive and selective determination of uric acid and glucose with smartphone as signal readout. In detail, chitosan, different kinds of chromogenic reagents, and horseradish peroxidase (HRP) combined with a specific oxidase, e.g., uricase or glucose oxidase (GOD), were immoblized onto the paper substrate to form a multilayer-modified test paper. Hydrogen peroxide produced by the oxidases (uricase or GOD) reacts with the substrates (uric acid or glucose), and could oxidize the co-immoblized chromogenic reagents to form colored products with HRP as catalyst. A simple strategy by placing the test paper on top of a light-emitting diode lamp was adopted to efficiently prevent influence from the external light. The color images were recorded by the smartphone camera, and then the gray values of the color images were calculated for quantitative analysis. The developed method provided a wide linear response from 0.01 to 1.0 mM for uric acid detection and from 0.02 to 4.0 mM for glucose detection, with a limit of detection (LOD) as low as 0.003 and 0.014 mM, respectively, which was much lower than for previously reported paper-based colorimetric assays. The proposed assays were successfully applied to uric acid and glucose detection in real serum samples. Furthermore, the enhanced analytical performance of the proposed method allowed the non-invasive detection of glucose levels in tear samples, which holds great potential for point-of-care analysis. Graphical abstract ᅟ.

  4. Colorimetric gold nanoparticles-based aptasensors

    Directory of Open Access Journals (Sweden)

    Rezavn Yazdian-Robati

    2018-01-01

    Full Text Available Recognition of different agents including chemical and biological plays important role in forensic, biomedical and environmentalfield.In recent decades, nanotechnology and nano materials had a high impact on development of sensors. Using  nanomaterials in construction of biosensors can effectively improve the Sensitivity and other features of biosensors. Different type of nanostructures including nanotubes, nanodiamonds, thin films ,nanorods, nanoparticles(NP, nanofibers andvarious clusters have been explored and applied in construction of biosensors. Among nanomaterials mentioned above, gold nanoparticle (GNPas a new class of unique fluorescence quenchers, is receiving significant attention in developing of optical biosensors because of their unique physical, chemical and biological properties. In this mini review, we discussed the use of GNPs in construction of colorimetric aptasensorsas a class of optical sensors for detection of antibiotics, toxins and infection diseases.

  5. SPE-HPLC purification of endocrine disrupting compounds from human serum for assessment of xenoestrogenic activity

    DEFF Research Database (Denmark)

    Hjelmborg, P.S.; Ghisari, Mandana; Bonefeld-Jørgensen, Eva

    2006-01-01

    Assessment of xenoestrogenic activity in human serum samples requires the removal of endogenous sex hormones to assure that the activity measured originates from xenobiotic compounds only. Serum samples representing high, medium and lower accumulation of persistent organic pollutants (POPs) were...... measured by ERE-CALUX was validated and considered to be a valuable tool to assess the combined ER effect of lipophilic serum POPs where additive/synergistic and agonistic/antagonistic effects are integrated giving an overall estimate of exposure and bioactivity....... for the study. MVLN cells, stably transfected with an estrogen receptor (ER) luciferase reporter vector (ERE-CALUX), were exposed to the reconstituted SPE-HPLC extracts for determination of the integrated estrogenic activity. The effects of PCBs were analyzed by direct in vitro exposure of PCBs (138, 153...

  6. Charge Transfer Based Colorimetric Detection of Silver Ion

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Choul; Kim, Kwang Seob; Choi, Soon Kyu; Oh, Jinho; Lee, Jae Wook [Dong-A Univ., Busan (Korea, Republic of)

    2014-05-15

    We have demonstrated the colorimetric chemosensor for detection of Ag{sup +} via formation of nanoparticles which is based on the intramolecular CT interaction between the electron-rich (2,6-dialkoxynaphthalene; Np) moiety and the electron-deficient (methyl viologen; MV{sup 2+}) moiety of a single sensor molecule. Under irradiation of light, Ag{sup +} was reduced to very small silver nanoparticle by CT interaction in the presence of OEGs as flexible recognition moiety of Ag{sup +} and stabilizer for Ag nanoparticles, thus Ag nanoparticles resulted to reddish brown in the color change of sensor solution, gradually. Therefore, the charge-transfer interaction between an electron-deficient and an electron-rich units existing at a sensor molecule can be regarded as a new and efficient method to construct various colorimetric chemosensors. Donor.acceptor interactions or charge transfer (CT) interactions are an important class of non-covalent interactions and have been widely exploited in self-assembling systems. Beyond molecular chemistry, supramolecular chemistry aims at constituting highly complex, functional chemical systems from components held together by intermolecular forces. Chemosensors are the molecules of abiotic origin that bind selectively and reversibly with the analyte with concomitant change in one or more properties of the system. The recognition and signaling of ionic and neutral species of varying complexity is one of the most intensively studied areas of contemporary supramolecular chemistry.

  7. Simple colorimetric detection of doxycycline and oxytetracycline using unmodified gold nanoparticles

    Science.gov (United States)

    Li, Jie; Fan, Shumin; Li, Zhigang; Xie, Yuanzhe; Wang, Rui; Ge, Baoyu; Wu, Jing; Wang, Ruiyong

    2014-08-01

    The interaction between tetracycline antibiotics and gold nanoparticles was studied. With citrate-coated gold nanoparticles as colorimetric probe, a simple and rapid detection method for doxycycline and oxytetracycline has been developed. This method relies on the distance-dependent optical properties of gold nanoparticles. In weakly acidic buffer medium, doxycycline and oxytetracycline could rapidly induce the aggregation of gold nanoparticles, resulting in red-to-blue (or purple) colour change. The experimental parameters were optimized with regard to pH, the concentration of the gold nanoparticles and the reaction time. Under optimal experimental conditions, the linear range of the colorimetric sensor for doxycycline/oxytetracycline was 0.06-0.66 and 0.59-8.85 μg mL-1, respectively. The corresponding limit of detection for doxycycline and oxytetracycline was 0.0086 and 0.0838 μg mL-1, respectively. This assay was sensitive, selective, simple and readily used to detect tetracycline antibiotics in food products.

  8. Effect of using heat-inactivated serum with the Abbott human T-cell lymphotropic virus type III antibody test.

    OpenAIRE

    Jungkind, D L; DiRenzo, S A; Young, S J

    1986-01-01

    The Abbott enzyme immunoassay (Abbott Laboratories, North Chicago, Ill.) for human T-cell lymphotropic virus type III (HTLV-III) antibody was evaluated to determine the effect of using heat-inactivated (56 degrees C for 30 min) serum as the sample. Each of 58 nonreactive serum samples gave a higher A492 value when tested after heat inactivation. Ten of the samples became reactive after heating. Heat-inactivated serum should not be used in the current Abbott HTLV-III antibody test, because thi...

  9. Comparison of inductively coupled plasma mass spectrometry and colorimetric determination of total and extractable phosphorus in soils

    International Nuclear Information System (INIS)

    Ivanov, Krasimir; Zaprjanova, Penka; Petkova, Milena; Stefanova, Violeta; Kmetov, Veselin; Georgieva, Deyana; Angelova, Violina

    2012-01-01

    The most widely used method for determination of total phosphorus in soils is perchloric acid digestion, followed by a colorimetric assay to measure the concentration of P in solution. The first part of this study compares an alternative digestion method, using aqua regia (ISO 11466 and EPA Method 3052), with perchloric acid digestion procedure, and also compares inductively coupled plasma mass spectroscopy (ICP-MS) with colorimetry for the measurement of P on the basis of five internationally certified standard soils and 20 real-life soils with widely different extractability of phosphorus. The phosphorus concentration was determined by means of the reduced phosphomolybdenum blue and ICP-MS. The relationship between methods has been examined statistically. Good agreement of the results from colorimetry and ICP-MS was established for all certified soils. The microwave-assisted digestion with aqua regia was comparable, both in precision and accuracy, with the hot plate aqua regia method. The phosphorus concentration found with the HF + HClO 4 digestion method was in good agreement with the certified mean values, while the superiority in extracting phosphorus, when compared to other methods, was obvious. Soil testing for plant-available phosphorus in Bulgaria and many European countries is most commonly conducted using acid Ca-lactate extraction (Egner–Riehm test) and alkaline sodium bicarbonate extraction (BDS ISO 11263:2002), based on Olsen test, followed by a colorimetric assay to measure the concentration of P in solution. The second part of this study reports the differences between Egner–Riehm test and BDS ISO 11263:2002 measured colorimetrically and by ICP-MS. Fifty soils were selected from South Bulgaria to represent a wide range of soil properties. It was established that ICP-MS consistently yielded significantly higher P concentrations than the colorimetric method in both extraction tests, and the relative differences were greatest in soils with lower P

  10. Comparison of inductively coupled plasma mass spectrometry and colorimetric determination of total and extractable phosphorus in soils

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Krasimir, E-mail: kivanov1@abv.bg [Department of Chemistry, University of Agriculture, Plovdiv (Bulgaria); Zaprjanova, Penka [Tobacco and Tobacco Products Institute, Plovdiv (Bulgaria); Petkova, Milena [Department of Chemistry, University of Agriculture, Plovdiv (Bulgaria); Stefanova, Violeta; Kmetov, Veselin; Georgieva, Deyana [Department of Analytical Chemistry, Plovdiv University ' Paisii Hilendarski,' Plovdiv (Bulgaria); Angelova, Violina [Department of Chemistry, University of Agriculture, Plovdiv (Bulgaria)

    2012-05-15

    The most widely used method for determination of total phosphorus in soils is perchloric acid digestion, followed by a colorimetric assay to measure the concentration of P in solution. The first part of this study compares an alternative digestion method, using aqua regia (ISO 11466 and EPA Method 3052), with perchloric acid digestion procedure, and also compares inductively coupled plasma mass spectroscopy (ICP-MS) with colorimetry for the measurement of P on the basis of five internationally certified standard soils and 20 real-life soils with widely different extractability of phosphorus. The phosphorus concentration was determined by means of the reduced phosphomolybdenum blue and ICP-MS. The relationship between methods has been examined statistically. Good agreement of the results from colorimetry and ICP-MS was established for all certified soils. The microwave-assisted digestion with aqua regia was comparable, both in precision and accuracy, with the hot plate aqua regia method. The phosphorus concentration found with the HF + HClO{sub 4} digestion method was in good agreement with the certified mean values, while the superiority in extracting phosphorus, when compared to other methods, was obvious. Soil testing for plant-available phosphorus in Bulgaria and many European countries is most commonly conducted using acid Ca-lactate extraction (Egner-Riehm test) and alkaline sodium bicarbonate extraction (BDS ISO 11263:2002), based on Olsen test, followed by a colorimetric assay to measure the concentration of P in solution. The second part of this study reports the differences between Egner-Riehm test and BDS ISO 11263:2002 measured colorimetrically and by ICP-MS. Fifty soils were selected from South Bulgaria to represent a wide range of soil properties. It was established that ICP-MS consistently yielded significantly higher P concentrations than the colorimetric method in both extraction tests, and the relative differences were greatest in soils with lower

  11. Covalent binding of nitrogen mustards to the cysteine-34 residue in human serum albumin

    NARCIS (Netherlands)

    Noort, D.; Hulst, A.G.; Jansen, R.

    2002-01-01

    Covalent binding of various clinically important nitrogen mustards to the cysteine-34 residue of human serum albumin, in vitro and in vivo, is demonstrated. A rapid method for detection of these adducts is presented, based on liquid chromatography-tandem mass spectrometry analysis of the adducted

  12. A soluble form of the high affinity IgE receptor, Fc-epsilon-RI, circulates in human serum.

    Directory of Open Access Journals (Sweden)

    Eleonora Dehlink

    Full Text Available Soluble IgE receptors are potential in vivo modulators of IgE-mediated immune responses and are thus important for our basic understanding of allergic responses. We here characterize a novel soluble version of the IgE-binding alpha-chain of Fc-epsilon-RI (sFcεRI, the high affinity receptor for IgE. sFcεRI immunoprecipitates as a protein of ∼40 kDa and contains an intact IgE-binding site. In human serum, sFcεRI is found as a soluble free IgE receptor as well as a complex with IgE. Using a newly established ELISA, we show that serum sFcεRI levels correlate with serum IgE in patients with elevated IgE. We also show that serum of individuals with normal IgE levels can be found to contain high levels of sFcεRI. After IgE-antigen-mediated crosslinking of surface FcεRI, we detect sFcεRI in the exosome-depleted, soluble fraction of cell culture supernatants. We further show that sFcεRI can block binding of IgE to FcεRI expressed at the cell surface. In summary, we here describe the alpha-chain of FcεRI as a circulating soluble IgE receptor isoform in human serum.

  13. Investigation of the proteins relaxation time in human blood serum; Badania relaksacyjne bialek surowicy krwi II

    Energy Technology Data Exchange (ETDEWEB)

    Blicharska, B.; Klauza, M. [Inst. Fizyki, Uniwersytet Jagiellonski, Cracow (Poland); Kuliszkiewicz-Janus, M. [Akademia Medyczna, Wroclaw (Poland)

    1994-12-31

    In this paper the results of human blood serum proteins relaxation time measurements by means of NMR method are presented. The measurements have been done for three samples of human blood: i/laudably ii/leukemia iii/granulomas. The dependences of the relaxation time on the temperature are also presented. 3 refs, 4 figs.

  14. Comparison of thiaminase activity in fish using the radiometric and 4-nitrothiophenol colorimetric methods

    Science.gov (United States)

    Honeyfield, D.C.; Hanes, J.W.; Brown, L.; Kraft, C.E.; Begley, T.P.

    2010-01-01

    Thiaminase induced thiamine deficiency occurs in fish, humans, livestock and wild animals. A non-radioactive thiaminase assay was described in 2007, but a direct comparison with the radioactive 14C-thiamine method which has been in use for more than 30years has not been reported. The objective was to measure thiaminase activity in forage fish (alewife Alosa pseudoharengus, rainbow smelt Osmerus mordax, and slimy sculpin Cottus cognatus) consumed by predators that manifest thiamine deficiency using both methods. Modifications were made to the colorimetric assay to improve repeatability. Modification included a change in assay pH, enhanced sample clean-up, constant assay temperature (37??C), increase in the concentration of 4-nitrothiophenol (4NTP) and use of a spectrophotometer fitted with a 0.2cm cell. A strong relationship between the two assays was found for 51 alewife (R2=0.85), 36 smelt (R2=0.87) and 20 sculpin (R2=0.82). Thiaminase activity in the colorimetric assay was about 1000 times higher than activity measured by the radioactive method. Application of the assay to fish species from which no thiaminase activity has previously been reported resulted in no 4NTP thiaminase activity being found in bloater Coregonus hoyi, lake trout Salvelinus namaycusch, steelhead trout Oncorhynchus mykiss or Chinook salmon Oncorhynchus tshawytscha. In species previously reported to contain thiaminase, 4NTP thiaminase activity was measured in bacteria Paenibacillus thiaminolyticus, gizzard shad Dorosoma cepedianum, bracken fern Pteridium aquilinum, quagga mussel Dreissena bugensis and zebra mussels D. polymorpha. ?? 2010.

  15. Proteome profiling analysis of human ovarian cancer serum samples

    International Nuclear Information System (INIS)

    Cognetti, F.; Citro, G.

    2009-01-01

    Mass Spectrometry represents a powerful tool in cancer research to discovery of potential bio markers through peak identification from serum profiling. By using high resolution MALDITOF and bioinformatic analysis almost 400 serum sample homogeneously distributed between biopsy confirmed ovarian cancer and high risk serum samples were analyzed. Each serum sample run in duplicate and whole serum sample preparation procedure has been performed by Hamilton Star Robot in order to reduce bias and the replicates with a low Pearson coefficient are removed. After automated reverse phase magnetic beads separation the samples were tested in MALDI-TOF

  16. Serum Zinc Level and Its Correlation with Vesikari System Scoring in Acute Pediatric Diarrhea.

    Science.gov (United States)

    Eskander, Ayman E; Sherif, Lobna S; Nabih, Mohammad; Baroudy, Nevine R El; Marcos, Ghobrial C; Badawy, Ehsan A; Refay, Amira S El

    2017-08-15

    Diarrhea remains the most common infectious disease worldwide. Zinc has been studied extensively recently for its potential effect on prevention, control and treatment of acute diarrhoea. This study was designed to correlate the level of zinc with the severity of pediatric diarrhoea estimated by Vesikari Scoring System. The present study included 80 children aged two months to 30 months from those suffering from the acute diarrheal episode and admitted to Pediatric Hospital "Abo El Rish" Cairo University. Serum Zinc level was assessed by a colorimetric method with a spectrophotometer. Zinc deficiency was detected in 45 (56.2%) patient of the studied group Significant negative correlations were found between serum zinc level and severity of dehydration and duration of hospitalization (p Zinc level has an essential role in acute pediatric diarrhoea. Zinc therapy should be considered beside Oral rehydration salts (ORS) to achieve maximum impact on diarrheal diseases; clinical trials are recommended to support the zinc supplementation in developing countries.

  17. Electrospun nanofiber based colorimetric probe for rapid detection of Fe{sup 2+} in water

    Energy Technology Data Exchange (ETDEWEB)

    Ondigo, D.A. [Department of Chemistry, Rhodes University, P.O. Box 94, Grahamstown 6140 (South Africa); Tshentu, Z.R. [Department of Chemistry, Rhodes University, P.O. Box 94, Grahamstown 6140 (South Africa); Department of Chemistry, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth, 6031 (South Africa); Torto, N., E-mail: N.Torto@ru.ac.za [Department of Chemistry, Rhodes University, P.O. Box 94, Grahamstown 6140 (South Africa)

    2013-12-04

    Graphical abstract: -- Highlights: •Colorimetric probe for the detection of Fe{sup 2+} was developed. •Polymeric electrospun nanofibers were used as host for the signaling reagent. •The functionalized electrospun nanofibers exhibited a selective color change in the presence of Fe{sup 2+}. •The mechanism was based on spin crossover (SCO) from high spin Fe{sup 2+} to low spin Fe{sup 2+} upon interaction with the embedded ligand. -- Abstract: An imidazole derivative, 2-(2′-pyridyl)imidazole (PIMH), was developed as a colorimetric probe for the qualitative analysis of Fe{sup 2+} in aqueous solution. PIMH was then used to post-functionalize poly(vinylbenzyl chloride) (PVBC) nanofibers after electrospinning so as to afford a solid state colorimetric probe. Upon treatment with Fe{sup 2+} the probe displayed a distinctive color change both in liquid and solid platforms. The linear dynamic range for the colorimetric determination of Fe{sup 2+} was 0.0988–3.5 μg mL{sup −1}. The ligand showed a high chromogenic selectivity for Fe{sup 2+} over other cations with a detection limit of 0.102 μg mL{sup −1} in solution (lower than the WHO drinking water guideline limit of 2 mg L{sup −1}), and 2 μg mL{sup −1} in the solid state. The concentration of Fe{sup 2+} in a certified reference material (Iron, Ferrous, 1072) was found to be 2.39 ± 0.01 mg L{sup −1}, which was comparable with the certified value of 2.44 ± 0.12 mg L{sup −1}. Application of the probe to real samples spiked with Fe{sup 2+} achieved recoveries of over 97% confirming accuracy of the method and its potential for on-site monitoring.

  18. 2.6. Sorption of serum albumin by ethynyl-piperidol hydrogels

    International Nuclear Information System (INIS)

    Khalikov, D.Kh.

    2012-01-01

    The sorption of serum albumin by ethynyl-piperidol hydrogels was studied in this article. Albumins adsorption on the surface of solids was considered. The capacity of cross-linked ethynyl piperidol polymers to the serum albumin was considered as well. The kinetic curves of sorption of human serum albumin by triple copolymer of isopropenyl trimethyl ethynyl piperidol were constructed. Sorption activity of ethynyl-piperidol polymers depending on ph of solution of human serum albumin were defined. Influence of solution ionic strength on sorption of human serum albumin was defined as well. The desorption of human serum albumin from the complexes with hydrogels was examined.

  19. Structural consistency analysis of recombinant and wild-type human serum albumin

    Science.gov (United States)

    Cao, Hui-Ling; Sun, Li-Hua; Liu, Li; Li, Jian; Tang, Lin; Guo, Yun-Zhu; Mei, Qi-Bing; He, Jian-Hua; Yin, Da-Chuan

    2017-01-01

    Recombinant human serum albumin (rHSA) is potential alternatives for human serum albumin (HSA) which may ease severe shortage of HSA worldwide. In theory, rHSA and HSA are the same. Structure decides function. Therefore, the 3D structural consistency analysis of rHSA and HSA is outmost importance, which is the base of their function consistency. In this paper, the crystal structures of rHSA at resolution limit of 2.22 Å and HSA at 2.30 Å were determined by X-ray diffraction (XRD), which were deposited in the Protein Data Bank (PDB) with accession codes 4G03 (rHSA) and 4G04 (HSA). The differences between rHSA and HSA were systematically analyzed from the crystallization behavior, diffraction data and three-dimensional (3D) structure. The superimposed contrasted analysis indicated that rHSA and HSA achieved a structural similarity of 99% with an r.m.s. deviation of 0.397 Å for the corresponding overall Cα atoms. In addition, the number of α-helices in the rHSA or HSA molecule was verified to be 30. As a result, rHSA can potentially replace HSA. The study provides a theoretical and experimental basis for the clinical and additional applications of rHSA. Meanwhile, it is also a good example for applications of genetic engineering.

  20. Analysis of DNA Hydroxymethylation Using Colorimetric Assay.

    Science.gov (United States)

    Golubov, Andrey; Kovalchuk, Igor

    2017-01-01

    Hydroxymethylcytosine (hmC or 5-hmC) is a nitrogen base occurring as a result of cytosine methylation followed by replacing a methyl group with a hydroxyl group through active oxidation. 5-hmC is considered to be one of the forms of epigenetic modification and is suggested as an intermediate step in a semi-active loss of DNA methylation mark. 5-hmC plays an important role in the epigenetic regulation of gene expression in animals, although its role in plants remains controversial. Here, we present a colorimetric method of quantification of 5-hmC using Brassica rapa DNA.

  1. Ischemic stroke progress evaluation by 31P NMR-based metabonomic of human serum

    International Nuclear Information System (INIS)

    Grandizoli, Caroline W.P.S.; Barison, Andersson; Lange, Marcos C.; Novak, Felipe T. M.; Campos, Francinete R.

    2014-01-01

    In this work, chemometric analyses over 31 P{ 1H } NMR (nuclear magnetic resonance) spectra of human blood serum permitted to discriminated ischemic stroke patients from health individuals due to changes in the chemical composition of phosphorus-containing compounds. These results indicate that 31 P NMR-based metabonomic allowed insights over the mechanism triggered by ischemic stroke. (author)

  2. Label-free aptamer-based colorimetric detection of mercury ions in aqueous media using unmodified gold nanoparticles as colorimetric probe

    Energy Technology Data Exchange (ETDEWEB)

    Li, Li; Li, Baoxin; Qi, Yingying; Jin, Yan [Shaanxi Normal University, Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Materials Science, Xi' an (China)

    2009-04-15

    We report a simple and sensitive aptamer-based colorimetric detection of mercury ions (Hg{sup 2+}) using unmodified gold nanoparticles as colorimetric probe. It is based on the fact that bare gold nanoparticles interact differently with short single-strand DNA and double-stranded DNA. The anti-Hg{sup 2+} aptamer is rich in thymine (T) and readily forms T-Hg{sup 2+}-T configuration in the presence of Hg{sup 2+}. By measuring color change or adsorption ratio, the bare gold nanoparticles can effectively differentiate the Hg{sup 2+}-induced conformational change of the aptamer in the presence of a given salt with high concentration. The assay shows a linear response toward Hg{sup 2+} concentration through a five-decade range of 1 x 10{sup -4} mol L{sup -1} to 1 x 10{sup -9} mol L{sup -1}. Even with the naked eye, we could identify micromolar Hg{sup 2+} concentrations within minutes. By using the spectrometric method, the detection limit was improved to the nanomolar range (0.6 nM). The assay shows excellent selectivity for Hg{sup 2+} over other metal cations including K{sup +}, Ba{sup 2+}, Ni{sup 2+}, Pb{sup 2+}, Cu{sup 2+}, Cd{sup 2+}, Mg{sup 2+}, Ca{sup 2+}, Zn{sup 2+}, Al{sup 3+}, and Fe{sup 3+}. The major advantages of this Hg{sup 2+} assay are its water-solubility, simplicity, low cost, visual colorimetry, and high sensitivity. This method provides a potentially useful tool for the Hg{sup 2+} detection. (orig.)

  3. Clinical significance of serum anti-human papillomavirus 16 and 18 antibodies in cervical neoplasia.

    Science.gov (United States)

    Chay, Doo Byung; Cho, Hanbyoul; Kim, Bo Wook; Kang, Eun Suk; Song, Eunseop; Kim, Jae-Hoon

    2013-02-01

    To estimate the clinical significance of serum anti-human papillomavirus (HPV) antibodies and high-risk cervical HPV DNA in cervical neoplasia. The study population comprised patients who were histopathologically diagnosed with cervical intraepithelial neoplasia (CIN) 1 (n=64), CIN 2 and 3 (n=241), cervical cancer (n=170), and normal control participants (n=975). Cervical HPV DNA tests were performed through nucleic acid hybridization assay tests, and serum anti-HPV 16 and 18 antibodies were measured by competitive immunoassay. The associations of HPV DNA and anti-HPV antibodies were evaluated with demographic characteristics and compared according to the levels of disease severity. Anti-HPV antibodies were also investigated with clinicopathologic parameters, including survival data. Among various demographic characteristics, factors involving sexual behavior had a higher tendency of HPV DNA positivity and HPV seropositivity. Human papillomavirus DNA mean titer and positivity were both increased in patients with cervical neoplasia compared with those with normal control participants, but there was no statistical difference among types of cervical neoplasia. Serum anti-HPV 16 antibodies were also able to differentiate cervical neoplasia from a normal control participant and furthermore distinguished CIN 1 from CIN 2 and 3 (odd ratio 2.87 [1.43-5.78], P=.002). In cervical cancer, HPV 16 seropositivity was associated with prolonged disease-free survival according to the univariable analysis (hazard ratio=0.12 [0.01-0.94], P=.044). Serum anti-HPV 16 antibodies can distinguish cervical neoplasia from a normal control and has the advantage of identifying high-grade CIN. Moreover, in cervical cancer, HPV 16 seropositivity may be associated with a more favorable prognosis. II.

  4. Improved detection of chemical substances from colorimetric sensor data using probabilistic machine learning

    DEFF Research Database (Denmark)

    Mølgaard, Lasse Lohilahti; Buus, Ole Thomsen; Larsen, Jan

    2017-01-01

    We present a data-driven machine learning approach to detect drug- and explosives-precursors using colorimetric sensor technology for air-sampling. The sensing technology has been developed in the context of the CRIM-TRACK project. At present a fully- integrated portable prototype for air sampling...... of the highly multi-variate data produced from the colorimetric chip a number of machine learning techniques are employed to provide reliable classification of target analytes from confounders found in the air streams. We demonstrate that a data-driven machine learning method using dimensionality reduction...... in combination with a probabilistic classifier makes it possible to produce informative features and a high detection rate of analytes. Furthermore, the probabilistic machine learning approach provides a means of automatically identifying unreliable measurements that could produce false predictions...

  5. Human blood serum analysis using TRXRF

    International Nuclear Information System (INIS)

    Zarkadas, C.; Karydas, A.G.; Paradellis, T.

    2000-01-01

    Total reflection x-ray fluorescence was applied in the analysis of a pool human blood serum sample, which was collected out of 100 healthy individuals during an ordinary day at a hospital in Athens. Direct measurements of 4 1 quantities were performed in a standard TRXRF module, but with the addition of a Mo filter after the cut-off reflector. In this way the exciting beam was further monochromatized leading to an improved peak to background ratio. The elements S, Cl, K, Ca, Fe, Cu, Zn, Se, Br, Rb were detected, with detection limits in the low ppb region for the elements of interest. The determined trace elements concentrations were found to be in very good agreement with values already reported in literature. For intercomparison a quantity of the same sample was freeze dried and measured in a secondary target assembly, in the form of pellets, giving almost identical results. The trace elements concentrations obtained can be considered as representative values for healthy population of Athens and therefore can be used as a monitor in order to associate the lack or excess of certain trace elements with pathological cases. (author)

  6. CONFORMATION CHANGES OF HUMAN SERUM γ–GLOBULIN IN THE PRESENCE OF ZINC IONS

    Directory of Open Access Journals (Sweden)

    S. B. Cheknev

    2005-01-01

    Full Text Available Abstract. Conformational changes of human serum γ–globulin during interaction with the zinc ions were studied in a solution. It has been shown that the presence of zinc in over its physiological concentrations led to increase in optical density across the whole spectrum of γ–globulin ultraviolet absorption. On the contrary, hypochromia in the spectrum was registered after interaction of the protein with zinc used in subphisiological concentrations. Possible role of divalent metal cations in changes in conformation of the blood serum γ–globulins, and thereby in regulation of their effector functions was discussed. (Med. Immunol., 2005, vol.7, № 4, pp. 375–380

  7. Application of silver films with different roughness parameter for septic human serum albumin detection by Surface Enhanced Raman Spectroscopy

    Science.gov (United States)

    Zyubin, A. Y.; Konstantinova, E. I.; Matveeva, K. I.; Slezhkin, V. A.; Samusev, I. G.; Demin, M. V.; Bryukhanov, V. V.

    2018-01-01

    In this paper, the rough silver films parameters investigation, used as media for surface enhancement Raman spectroscopy for health and septic human serum albumin (HSA) study results have been presented. The detection of small concentrations of HSA isolated from blood serum and it main vibrational groups identification has been done.

  8. A Universal Fast Colorimetric Method for DNA Signal Detection with DNA Strand Displacement and Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Xin Li

    2015-01-01

    Full Text Available DNA or gene signal detection is of great significance in many fields including medical examination, intracellular molecular monitoring, and gene disease signal diagnosis, but detection of DNA or gene signals in a low concentration with instant visual results remains a challenge. In this work, a universal fast and visual colorimetric detection method for DNA signals is proposed. Specifically, a DNA signal amplification “circuit” based on DNA strand displacement is firstly designed to amplify the target DNA signals, and then thiol modified hairpin DNA strands and gold nanoparticles are used to make signal detection results visualized in a colorimetric manner. If the target DNA signal exists, the gold nanoparticles aggregate and settle down with color changing from dark red to grey quickly; otherwise, the gold nanoparticles’ colloids remain stable in dark red. The proposed method provides a novel way to detect quickly DNA or gene signals in low concentrations with instant visual results. When applied in real-life, it may provide a universal colorimetric method for gene disease signal diagnosis.

  9. Comparison of FTIR-ATR and Raman spectroscopy in determination of VLDL triglycerides in blood serum with PLS regression

    Science.gov (United States)

    Oleszko, Adam; Hartwich, Jadwiga; Wójtowicz, Anna; Gąsior-Głogowska, Marlena; Huras, Hubert; Komorowska, Małgorzata

    2017-08-01

    Hypertriglyceridemia, related with triglyceride (TG) in plasma above 1.7 mmol/L is one of the cardiovascular risk factors. Very low density lipoproteins (VLDL) are the main TG carriers. Despite being time consuming, demanding well-qualified staff and expensive instrumentation, ultracentrifugation technique still remains the gold standard for the VLDL isolation. Therefore faster and simpler method of VLDL-TG determination is needed. Vibrational spectroscopy, including FT-IR and Raman, is widely used technique in lipid and protein research. The aim of this study was assessment of Raman and FT-IR spectroscopy in determination of VLDL-TG directly in serum with the isolation step omitted. TG concentration in serum and in ultracentrifugated VLDL fractions from 32 patients were measured with reference colorimetric method. FT-IR and Raman spectra of VLDL and serum samples were acquired. Partial least square (PLS) regression was used for calibration and leave-one-out cross validation. Our results confirmed possibility of reagent-free determination of VLDL-TG directly in serum with both Raman and FT-IR spectroscopy. Quantitative VLDL testing by FT-IR and/or Raman spectroscopy applied directly to maternal serum seems to be promising screening test to identify women with increased risk of adverse pregnancy outcomes and patient friendly method of choice based on ease of performance, accuracy and efficiency.

  10. Trypanosoma brucei gambiense group 1 is distinguished by a unique amino acid substitution in the HpHb receptor implicated in human serum resistance.

    Directory of Open Access Journals (Sweden)

    Rebecca E Symula

    Full Text Available Trypanosoma brucei rhodesiense (Tbr and T. b. gambiense (Tbg, causative agents of Human African Trypanosomiasis (sleeping sickness in Africa, have evolved alternative mechanisms of resisting the activity of trypanosome lytic factors (TLFs, components of innate immunity in human serum that protect against infection by other African trypanosomes. In Tbr, lytic activity is suppressed by the Tbr-specific serum-resistance associated (SRA protein. The mechanism in Tbg is less well understood but has been hypothesized to involve altered activity and expression of haptoglobin haemoglobin receptor (HpHbR. HpHbR has been shown to facilitate internalization of TLF-1 in T.b. brucei (Tbb, a member of the T. brucei species complex that is susceptible to human serum. By evaluating the genetic variability of HpHbR in a comprehensive geographical and taxonomic context, we show that a single substitution that replaces leucine with serine at position 210 is conserved in the most widespread form of Tbg (Tbg group 1 and not found in related taxa, which are either human serum susceptible (Tbb or known to resist lysis via an alternative mechanism (Tbr and Tbg group 2. We hypothesize that this single substitution contributes to reduced uptake of TLF and thus may play a key role in conferring serum resistance to Tbg group 1. In contrast, similarity in HpHbR sequence among isolates of Tbg group 2 and Tbb/Tbr provides further evidence that human serum resistance in Tbg group 2 is likely independent of HpHbR function.

  11. Generation of hematopoietic stem cells from human embryonic stem cells using a defined, stepwise, serum-free, and serum replacement-free monolayer culture method.

    Science.gov (United States)

    Kim, So-Jung; Jung, Ji-Won; Ha, Hye-Yeong; Koo, Soo Kyung; Kim, Eung-Gook; Kim, Jung-Hyun

    2017-03-01

    Embryonic stem cells (ESCs) can be expanded infinitely in vitro and have the potential to differentiate into hematopoietic stem cells (HSCs); thus, they are considered a useful source of cells for HSC production. Although several technical in vitro methods for engineering HSCs from pluripotent stem cells have been developed, clinical application of HSCs engineered from pluripotent stem cells is restricted because of the possibility of xenogeneic contamination resulting from the use of murine materials. Human ESCs (CHA-hES15) were cultured on growth factor-reduced Matrigel-coated dishes in the mTeSR1 serum-free medium. When the cells were 70% confluent, we initiated HSC differentiation by three methods involving (1) knockout serum replacement (KSR), cytokines, TGFb1, EPO, and FLT3L; (2) KSR, cytokines, and bFGF; or (3) cytokines and bFGF. Among the three differentiation methods, the minimal number of cytokines without KSR resulted in the greatest production of HSCs. The optimized method resulted in a higher proportion of CD34 + CD43 + hematopoietic progenitor cells (HPCs) and CD34 + CD45 + HPCs compared to the other methods. In addition, the HSCs showed the potential to differentiate into multiple lineages of hematopoietic cells in vitro . In this study, we optimized a two-step, serum-free, animal protein-free, KSR-free, feeder-free, chemically defined monolayer culture method for generation of HSCs and hematopoietic stem and progenitor cells (HSPCs) from human ESCs.

  12. Decreased Serum Lipids in Patients with Probable Alzheimer´s Disease

    Directory of Open Access Journals (Sweden)

    Orhan Lepara

    2009-08-01

    Full Text Available Alzheimer’s disease (AD is a multifactorial disease but its aetiology and pathophisiology are still not fully understood. Epidemiologic studies examining the association between lipids and dementia have reported conflicting results. High total cholesterol has been associated with both an increased, and decreased, risk of AD and/or vascular dementia (VAD, whereas other studies found no association. The aim of this study was to investigate the serum lipids concentration in patients with probable AD, as well as possible correlation between serum lipids concentrations and cognitive impairment.Our cross-sectional study included 30 patients with probable AD and 30 age and sex matched control subjects. The probable AD was clinically diagnosed by NINCDS-ADRDA criteria. Serum total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C and triglyceride (TG levels were determined at the initial assessment using standard enzymatic colorimetric techniques. Low-den- sity lipoprotein cholesterol (LDL-C and very low density lipoprotein cholesterol (VLDL-C levels were calculated. Subjects with probable AD had significantly lower serum TG (p<0,01, TC (p<0,05, LDL-C (p<0,05 and VLDL-C (p<0,01 compared to the control group. We did not observe signifi-cant difference in HDL-C level between patients with probable AD and control subjects. Negative, although not significant correlation between TG, TC and VLDL-C and MMSE in patients with AD was observed. In the control group of subjects there was a negative correlation between TC and MMSE but it was not statistically significant (r = -0,28. Further studies are required to explore the possibility for serum lipids to serve as diagnostic and therapeutic markers of AD.

  13. Crystal structure analysis of human serum albumin complexed with sodium 4-phenylbutyrate

    Directory of Open Access Journals (Sweden)

    Akito Kawai

    2018-03-01

    Full Text Available Sodium 4-phenylbutyrate (PB is an orphan drug for the treatment of urea cycle disorders. It also inhibits the development of endoplasmic reticulum stress, the action of histone deacetylases and as a regulator of the hepatocanalicular transporter. PB is generally considered to have the potential for use in the treatment of the diseases such as cancer, neurodegenerative diseases and metabolic diseases. In a previous study, we reported that PB is primarily bound to human serum albumin (HSA in plasma and its binding site is drug site 2. However, details of the binding mode of PB to HSA remain unknown. To address this issue, we examined the crystal structure of HSA with PB bound to it. The structure of the HSA–PB complex indicates that the binding mode of PB to HSA is quite similar to that for octanoate or drugs that bind to drug site 2, as opposed to that for other medium-chain length of fatty acids. These findings provide useful basic information related to drug–HSA interactions. Moreover, the information presented herein is valuable in terms of providing safe and efficient treatment and diagnosis in clinical settings. Keywords: Human serum albumin, X-ray crystallography, Sodium 4-phenylbutyrate, Drug interaction, Drug site 2

  14. The role of albumin conformation in the binding of diazepam to human serum albumin

    NARCIS (Netherlands)

    Wilting, J.; Hart, B.J. 't; Gier, J.J. de

    2006-01-01

    The effect of hydrogen, chloride and calcium ions on the binding of diazepare to human serum albumin has been studied by circular dichroism and equilibrium dialysis. In all cases the molar ellipticity of the diazepam-albumin complex increases with pH over the pH range 5 to 9. Under these

  15. Deep-Dive Targeted Quantification for Ultrasensitive Analysis of Proteins in Nondepleted Human Blood Plasma/Serum and Tissues

    Energy Technology Data Exchange (ETDEWEB)

    Nie, Song [Biological Sciences Division; Shi, Tujin [Biological Sciences Division; Fillmore, Thomas L. [Biological Sciences Division; Schepmoes, Athena A. [Biological Sciences Division; Brewer, Heather [Biological Sciences Division; Gao, Yuqian [Biological Sciences Division; Song, Ehwang [Biological Sciences Division; Wang, Hui [Biological Sciences Division; Rodland, Karin D. [Biological Sciences Division; Qian, Wei-Jun [Biological Sciences Division; Smith, Richard D. [Biological Sciences Division; Liu, Tao [Biological Sciences Division

    2017-08-11

    Mass spectrometry-based targeted proteomics (e.g., selected reaction monitoring, SRM) is emerging as an attractive alternative to immunoassays for protein quantification. Recently we have made significant progress in SRM sensitivity for enabling quantification of low ng/mL to sub-ng/mL level proteins in nondepleted human blood plasma/serum without affinity enrichment. However, precise quantification of extremely low abundant but biologically important proteins (e.g., ≤100 pg/mL in blood plasma/serum) using targeted proteomics approaches still remains challenging. To address this need, we have developed an antibody-independent Deep-Dive SRM (DD-SRM) approach that capitalizes on multidimensional high-resolution reversed-phase liquid chromatography (LC) separation for target peptide enrichment combined with precise selection of target peptide fractions of interest, significantly improving SRM sensitivity by ~5 orders of magnitude when compared to conventional LC-SRM. Application of DD-SRM to human serum and tissue has been demonstrated to enable precise quantification of endogenous proteins at ~10 pg/mL level in nondepleted serum and at <10 copies per cell level in tissue. Thus, DD-SRM holds great promise for precisely measuring extremely low abundance proteins or protein modifications, especially when high-quality antibody is not available.

  16. Zinc in human serum. Biochemical and clinical aspects. Zink i humant serum. Biokemiske og kliniske aspekter

    Energy Technology Data Exchange (ETDEWEB)

    Kiilerich, S

    1987-01-01

    The zinc ion is essential for the living organism. Many pathological conditions have been described as a consequence of zinc deficiency. As zinc constitutes less than 0.01 percent of the body weight, it conventionally belongs to the group of trace elements. The method of atomic absorption spectrophotometry is used to measure the concentration of zinc in serum and urine from healthy persons. The assumptions of the method is discussed. The importance of protein binding, diet and the diurnal variation of serum zinc concentration is presented. Serum versus plasma zinc concentration is discussed. Reference serum zinc values from 104 normal subjects are given. Zinc in serum is almost entirely bound to proteins. A preliminary model for the estimation of the distribution of zinc between serum albumin and ..cap alpha../sub 2/-macroglobulin is set up. This estimate has been examined by an ultracentrufugation method. The binding of zinc to a ..cap alpha../sup 2/-macroglobulin in normal persons is appoximately 7 percent, in patients with cirrhosis of the liver of alcoholic origin approximately 6 percent, in patients with insulin dependent diabetes mellitus approximately 5 percent, and in patients with chronic renal failure approximately 2 percent. It is concluded, therefore, that for clinical purposes it is sufficient to use the concentration of total serum zinc corrected for the concentration of serum albumin.

  17. Per- and polyfluoroalkyl substances in human serum and urine samples from a residentially exposed community.

    Science.gov (United States)

    Worley, Rachel Rogers; Moore, Susan McAfee; Tierney, Bruce C; Ye, Xiaoyun; Calafat, Antonia M; Campbell, Sean; Woudneh, Million B; Fisher, Jeffrey

    2017-09-01

    Per- and polyfluoroalkyl substances (PFAS) are considered chemicals of emerging concern, in part due to their environmental and biological persistence and the potential for widespread human exposure. In 2007, a PFAS manufacturer near Decatur, Alabama notified the United States Environmental Protection Agency (EPA) it had discharged PFAS into a wastewater treatment plant, resulting in environmental contamination and potential exposures to the local community. To characterize PFAS exposure over time, the Agency for Toxic Substances and Disease Registry (ATSDR) collected blood and urine samples from local residents. Eight PFAS were measured in serum in 2010 (n=153). Eleven PFAS were measured in serum, and five PFAS were measured in urine (n=45) from some of the same residents in 2016. Serum concentrations were compared to nationally representative data and change in serum concentration over time was evaluated. Biological half-lives were estimated for perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorohexane sulfonic acid (PFHxS) using a one-compartment pharmacokinetic model. In 2010 and 2016, geometric mean PFOA and PFOS serum concentrations were elevated in participants compared to the general U.S. In 2016, the geometric mean PFHxS serum concentration was elevated compared to the general U.S. Geometric mean serum concentrations of PFOA, PFOS, and perfluorononanoic acid (PFNA) were significantly (p≤0.0001) lower (49%, 53%, and 58%, respectively) in 2016 compared to 2010. Half-lives for PFOA, PFOS, and PFHxS were estimated to be 3.9, 3.3, and 15.5years, respectively. Concentrations of PFOA in serum and urine were highly correlated (r=0.75) in males. Serum concentrations of some PFAS are decreasing in this residentially exposed community, but remain elevated compared to the U.S. general population. Published by Elsevier Ltd.

  18. Identification of drug metabolites in human plasma or serum integrating metabolite prediction, LC-HRMS and untargeted data processing

    NARCIS (Netherlands)

    Jacobs, P.L.; Ridder, L.; Ruijken, M.; Rosing, H.; Jager, N.G.L.; Beijnen, J.H.; Bas, R.R.; Dongen, W.D. van

    2013-01-01

    Background: Comprehensive identification of human drug metabolites in first-in-man studies is crucial to avoid delays in later stages of drug development. We developed an efficient workflow for systematic identification of human metabolites in plasma or serum that combines metabolite prediction,

  19. Simultaneous radioimmunoassay for corticosterone and deoxycortisol in human serum: Sex differences in the mean serum concentrations

    International Nuclear Information System (INIS)

    Schoeneshoefer, M.; Harendt, H.; Vecsei, P.

    1977-01-01

    A specific radioimmunoassay is described which allows the simultaneous determination of serum corticosterone and deoxycortisol. The normal serum concentration of both steroids were found to be dependent on sex and menstrual cycle. Mean concentrations (+-S.D.) in males, females (follicular phase) and females (luteal phase) were 4210 +- 2170 ng/l, 2410 +- 1480 ng/l and 4390 +- 2320 ng/l for corticosterone and 499 +- 273 ng/l, 207 +- 152 ng/l and 335 +- 182 ng/l for deoxycortisol. After adrenal stimulation by corticotropin itself or by insulin induced hypoglycemia, the serum concentrations of corticosterone became significantly higher than those of deoxycortisol. After oral administration of dexamethasone serum concentrations of both steroids were suppressed to levels below the limit of the normal range. One hour after oral metyrapone administration at midnight, serum corticosterone decreased, while serum deoxycortisol increased by a factor of about five. After eight hours serum concentrations of both steroids were increased considerably. Corticosterone attained levels slightly higher than the normal range and deoxycortisol rose to levels which were higher than the normal mean concentrations by a factor of about 500. (orig./AS) [de

  20. Investigation of the interaction between isomeric derivatives and human serum albumin by fluorescence spectroscopy and molecular modeling

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruiyong, E-mail: wangry@zzu.edu.cn; Dou, Huanjing; Yin, Yujing; Xie, Yuanzhe; Sun, Li; Liu, Chunmei; Dong, Jingjing; Huang, Gang; Zhu, Yanyan; Song, Chuanjun, E-mail: chjsong@zzu.edu.cn; Chang, Junbiao, E-mail: changjunbiao@zzu.edu.cn

    2014-10-15

    In this paper, we have synthesized 9H-pyrrolo[1,2-a]indol-9-ones and the isomeric indeno[2,1-b]pyrrol-8-ones. The interactions of human serum albumin with series of isomeric derivatives have been studied by spectrophotometric methods. Results show the intrinsic fluorescence is quenched by the derivatives with a static quenching procedure. The thermodynamics parameters indicate that van der Waals forces and hydrogen bonds play a major role in the interactions. The results of synchronous fluorescence spectra demonstrate that the microenvironments of Trp residue of human serum albumin are disturbed by most derivatives. Thermodynamic results showed that the 9H-pyrrolo[1,2-a]indol-9-ones are stronger quenchers and bind to human serum albumin with the higher affinity than isomeric indeno[2,1-b]pyrrol-8-ones. The influence of molecular structure on the binding aspects has been investigated. - Highlights: • The interactions between isomeric derivatives and HSA have been investigated. • Results reveal that 9H-pyrrolo[1,2-a]indol-9-ones are stronger quenchers for HSA. • Hydrogen bonds and van der Waals forces play major role in the binding process. • The influence of molecular structure on the binding aspects has been investigated. • The binding study was also modeled by molecular docking.

  1. Investigation of the interaction between isomeric derivatives and human serum albumin by fluorescence spectroscopy and molecular modeling

    International Nuclear Information System (INIS)

    Wang, Ruiyong; Dou, Huanjing; Yin, Yujing; Xie, Yuanzhe; Sun, Li; Liu, Chunmei; Dong, Jingjing; Huang, Gang; Zhu, Yanyan; Song, Chuanjun; Chang, Junbiao

    2014-01-01

    In this paper, we have synthesized 9H-pyrrolo[1,2-a]indol-9-ones and the isomeric indeno[2,1-b]pyrrol-8-ones. The interactions of human serum albumin with series of isomeric derivatives have been studied by spectrophotometric methods. Results show the intrinsic fluorescence is quenched by the derivatives with a static quenching procedure. The thermodynamics parameters indicate that van der Waals forces and hydrogen bonds play a major role in the interactions. The results of synchronous fluorescence spectra demonstrate that the microenvironments of Trp residue of human serum albumin are disturbed by most derivatives. Thermodynamic results showed that the 9H-pyrrolo[1,2-a]indol-9-ones are stronger quenchers and bind to human serum albumin with the higher affinity than isomeric indeno[2,1-b]pyrrol-8-ones. The influence of molecular structure on the binding aspects has been investigated. - Highlights: • The interactions between isomeric derivatives and HSA have been investigated. • Results reveal that 9H-pyrrolo[1,2-a]indol-9-ones are stronger quenchers for HSA. • Hydrogen bonds and van der Waals forces play major role in the binding process. • The influence of molecular structure on the binding aspects has been investigated. • The binding study was also modeled by molecular docking

  2. Influence of starvation, triton WR-1339 and [131I]-human serum albumin on rat liver lysosomes

    International Nuclear Information System (INIS)

    Harikumar, P.; Ninjoor, V.

    1986-01-01

    The response of rat liver lysosomes to starvation and administration of lysosomotropic agents viz. Triton WR-1339 and [ 131 I]-human serum albumin, was assessed in terms of their distribution pattern after isopycnic sucrose density gradient centrifugation. Starvation induced changes in lysosomes appeared to be similar to that produced by the detergent uptake. Both the treatments caused a distinct decline in the equilibration densities of the organelles. On the other hand, injected labelled protein failed to comigrate with the lysosomal markers in starved as well as Triton treated rats and conspicuously remained in a region of high specific gravity in the gradient. These findings indicate retarded fusion between secondary lysosomes and [ 131 I]-human serum albumin containing phagosomes in the livers of rats subjected to starvation or detergent treatment. (author)

  3. Quantification of a cardiac biomarker in human serum using extraordinary optical transmission (EOT.

    Directory of Open Access Journals (Sweden)

    Tao Ding

    Full Text Available Nanoimprinting lithography (NIL is a manufacturing process that can produce macroscale surface areas with nanoscale features. In this paper, this technique is used to solve three fundamental issues for the application of localized surface plasmonic resonance (LSPR in practical clinical measurements: assay sensitivity, chip-to-chip variance, and the ability to perform assays in human serum. Using NIL, arrays of 140 nm square features were fabricated on a sensing area of 1.5 mm x 1.5 mm with low cost. The high reproducibility of NIL allowed for the use of a one-chip, one-measurement approach with 12 individually manufactured surfaces with minimal chip-to-chip variations. To better approximate a real world setting, all chips were modified with a biocompatible, multi-component monolayer and inter-chip variability was assessed by measuring a bioanalyte standard (2.5-75 ng/ml in the presence of a complex biofluid, human serum. In this setting, nanoimprinted LSPR chips were able to provide sufficient characteristics for a 'low-tech' approach to laboratory-based bioanalyte measurement, including: 1 sufficient size to interface with a common laboratory light source and detector without the need for a microscope, 2 high sensitivity in serum with a cardiac troponin limit of detection of 0.55 ng/ml, and 3 very low variability in chip manufacturing to produce a figure of merit (FOM of 10.5. These findings drive LSPR closer to technical comparability with ELISA-based assays while preserving the unique particularities of a LSPR based sensor, suitability for multiplexing and miniaturization, and point-of-care detections.

  4. Detection of Carbendazim Residues with a Colorimetric Sensor Based on Gold Nanoparticles

    Science.gov (United States)

    Ma, Y.; Jiang, H.; Shen, C.; Hou, Ch.; Huo, D.; Wu, H.; Yang, M.

    2017-07-01

    Carbendazim is among the most popular benzimidazole bactericides that are widely used to boost food production, and its residue poses a great threat to human health and the environment. In this paper, we presented a colorimetric sensor based on gold nanoparticles (Au-NPs) for the detection of carbendazim residues. The Au-NPs were stabilized by citric acid synthesized by chloroauric acid and sodium citrate with a diameter of about 13 nm. Upon reaction with carbendazim, the sensor gave a clear color change that could be distinguished with the naked eye. Thus we elaborated a new method for rapid determination of this benzimidazole bactericide. After optimization of the detection conditions, the sensor showed a very good linear relationship with the carbendazim concentrations varying from 10 to 600 ppb with a detection limit down to 3.4 ppb (S/N = 3). These preliminary results demonstrate that the presented sensor is promising for fast carbendazim analysis.

  5. Human dental pulp stem cells cultured in serum-free supplemented medium

    Directory of Open Access Journals (Sweden)

    Virginie eBonnamain

    2013-12-01

    Full Text Available Growing evidence show that human dental pulp stem cells (DPSCs could provide a source of adult stem cells for the treatment of neurodegenerative pathologies. In this study, DPSCs were expanded and cultured with a protocol generally used for the culture of neural stem/progenitor cells.Methodology: DPSC cultures were established from third molars. The pulp tissue was enzymatically digested and cultured in serum-supplemented basal medium for 12 hours. Adherent (ADH and non-adherent (non-ADH cell populations were separated according to their differential adhesion to plastic and then cultured in serum-free defined N2 medium with epidermal growth factor (EGF and basic fibroblast growth factor (bFGF. Both ADH and non-ADH populations were analyzed by FACS and/or PCR.Results: FACS analysis of ADH-DPSCs revealed the expression of the mesenchymal cell marker CD90, the neuronal marker CD56, the transferrin receptor CD71, and the chemokine receptor CXCR3, whereas hematopoietic stem cells markers CD45, CD133 and CD34 were not expressed. ADH-DPSCs expressed transcripts coding for the Nestin gene, whereas expression levels of genes coding for the neuronal markers β-III tubulin and NF-M, and the oligodendrocyte marker PLP-1 were donor dependent. ADH-DPSCs did not express the transcripts for GFAP, an astrocyte marker. Cells of the non-ADH population that grew as spheroids expressed Nestin, β-III tubulin, NF-M and PLP-1 transcripts. DPSCs migrated out of the spheroids exhibited an odontoblast-like morphology and expressed a higher level of DSPP and osteocalcin transcripts than ADH-DPSCs. Conclusion: Collectively, these data indicate that human DPSCs can be expended and cultured in serum-free supplemented medium with EGF and bFGF. ADH-DPSCs and non-ADH populations contained neuronal and/or oligodendrocyte precursors at different stages of commitment and interestingly, cells from spheroid structures seem to be more engaged into the odontoblastic lineage than the

  6. A new rapid method for quantification of nitrogen in human serum employing the 14N(p,p' γ)14N reaction: application to human pregnancy

    International Nuclear Information System (INIS)

    Nikkenien, P.; Hyvoenen-Dabek, M.; Raeisaenen, J.; Haenninen, R.; Dabek, J.T.

    1985-01-01

    The total nitrogen concentrations in dried serum from 54 pregnant women and 17 newborn babies were determined by a new application of the 14 N(p,p'γ) 14 N reaction resonance at 3.9 MeV. The samples were bombarded in a He atmosphere by 4.1 MeV protons from a tandem Van de Graaff accelerator. The mean dry-weight nitrogen concentration in serum sampled during early pregnancy (6-12 weeks; 13.9 g per 100 g+-5.4%) was significantly higher than that in serum sampled during late pregnancy (38-42 weeks: 13.0 g per 100 g+-3.9%, p<0.001) than that in serum taken from the umbilical cord (13.3 g per 100 g+-4.6%, p<0.01). The nitrogen levels measured using this rapid nuclear technique, applied for the first time to human serum analysis, agree well with parallel Kjeldahl analyses. (author)

  7. [Colorimetric detection of HPV6 and HPV16 by loop mediated isothermal amplification].

    Science.gov (United States)

    Lu, Chun-bin; Luo, Le; Yang, Meng-jie; Nie, Kai; Wang, Miao; Ma, Xue-Jun

    2011-01-01

    A simple, rapid and sensitive colorimetric loop mediated isothermal amplification (LAMP) method was established to detect HPV6 and HPV 16 respectively. The method employed a set of four specially designed primers that recognized six distinct sequences of HPV6-E6 or HPV16-E7 for amplification of nucleic acid under isothermal conditions at 63 degrees C for one hour. The amplification process of LAMP was monitored by the addition of HNB (hydroxy naphthol blue) dye prior to amplification. A positive reaction was indicated by a color change from violet to sky blue and confirmed by real-time turbidimeter and agarose electrophoresis. Thirteen cervical swab samples having single infection with 13 different HPV genotypes were examined to evaluate the specificity. A serial dilution of a cloned plasmid containing HPV-E6 or HPV-E7 gene was examined to evaluate the sensitivity. The results showed that no cross-reaction with other HPV genotypes was observed. The colorimetric LAMP assay could achieve a sensitivity of 1000 copies, 10-20 times lower than that of real-time PCR. The assay was further evaluated with 62 clinical specimens and consistent results were obtained compared with the detection using Kai Pu HPV Genotyping Kit. We concluded that this colorimetric LAMP assay had potential usefulness for the rapid screening of the HPV6 or HPV16 infection in the laboratories and hospitals of provincial and municipal region in China.

  8. THE EFFECTS OF GLYCATION ON THE BINDING OF HUMAN SERUM ALBUMIN TO WARFARIN AND L-TRYPTOPHAN

    OpenAIRE

    Joseph, K.S.; Hage, David S.

    2010-01-01

    Diabetes leads to elevated levels of glucose in blood which, in turn, can lead to the non-enzymatic glycation of serum proteins such as human serum albumin (HSA). It has been suggested that this increase in glycation can alter the ability of HSA to bind to drugs and other small solutes. This study used high-performance affinity chromatography (HPAC) to see if there is any significant change related to glycation in the binding of HSA to warfarin and L-tryptophan, which are often used as probe ...

  9. Glycoblotting method allows for rapid and efficient glycome profiling of human Alzheimer's disease brain, serum and cerebrospinal fluid towards potential biomarker discovery.

    Science.gov (United States)

    Gizaw, Solomon T; Ohashi, Tetsu; Tanaka, Masakazu; Hinou, Hiroshi; Nishimura, Shin-Ichiro

    2016-08-01

    Understanding of the significance of posttranslational glycosylation in Alzheimer's disease (AD) is of growing importance for the investigation of the pathogenesis of AD as well as discovery research of the disease-specific serum biomarkers. We designed a standard protocol for the glycoblotting combined with MALDI-TOFMS to perform rapid and quantitative profiling of the glycan parts of glycoproteins (N-glycans) and glycosphingolipids (GSLs) using human AD's post-mortem samples such as brain tissues (dissected cerebral cortices such as frontal, parietal, occipital, and temporal domains), serum and cerebrospinal fluid (CSF). The structural profiles of the major N-glycans released from glycoproteins and the total expression levels of the glycans were found to be mostly similar between the brain tissues of the AD patients and those of the normal control group. In contrast, the expression levels of the serum and CSF protein N-glycans such as bisect-type and multiply branched glycoforms were increased significantly in AD patient group. In addition, the levels of some gangliosides such as GM1, GM2 and GM3 appeared to alter in the AD patient brain and serum samples when compared with the normal control groups. Alteration of the expression levels of major N- and GSL-glycans in human brain tissues, serum and CSF of AD patients can be monitored quantitatively by means of the glycoblotting-based standard protocols. The changes in the expression levels of the glycans derived from the human post-mortem samples uncovered by the standardized glycoblotting method provides potential serum biomarkers in central nervous system disorders and can contribute to the insight into the molecular mechanisms in the pathogenesis of neurodegenerative diseases and future drug discovery. Most importantly, the present preliminary trials using human post-mortem samples of AD patients suggest that large-scale serum glycomics cohort by means of various-types of human AD patients as well as the normal

  10. Genetic, anatomic, and clinical determinants of human serum sterol and vitamin D levels.

    Science.gov (United States)

    Stiles, Ashlee R; Kozlitina, Julia; Thompson, Bonne M; McDonald, Jeffrey G; King, Kevin S; Russell, David W

    2014-09-23

    An unknown fraction of the genome participates in the metabolism of sterols and vitamin D, two classes of lipids with diverse physiological and pathophysiological roles. Here, we used mass spectrometry to measure the abundance of >60 sterol and vitamin D derivatives in 3,230 serum samples from a well-phenotyped patient population. Twenty-nine of these lipids were detected in a majority of samples at levels that varied over thousands of fold in different individuals. Pairwise correlations between sterol and vitamin D levels revealed evidence for shared metabolic pathways, additional substrates for known enzymes, and transcriptional regulatory networks. Serum levels of multiple sterols and vitamin D metabolites varied significantly by sex, ethnicity, and age. A genome-wide association study identified 16 loci that were associated with levels of 19 sterols and 25-hydroxylated derivatives of vitamin D (P < 10(-7)). Resequencing, expression analysis, and biochemical experiments focused on one such locus (CYP39A1), revealed multiple loss-of-function alleles with additive effects on serum levels of the oxysterol, 24S-hydroxycholesterol, a substrate of the encoded enzyme. Body mass index, serum lipid levels, and hematocrit were strong phenotypic correlates of interindividual variation in multiple sterols and vitamin D metabolites. We conclude that correlating population-based analytical measurements with genotype and phenotype provides productive insight into human intermediary metabolism.

  11. Silver nanoparticles-based colorimetric array for the detection of Thiophanate-methyl

    Science.gov (United States)

    Zheng, Mingda; Wang, Yingying; Wang, Chenge; Wei, Wei; Ma, Shuang; Sun, Xiaohan; He, Jiang

    2018-06-01

    A simple and selective colorimetric sensor based on citrate capped silver nanoparticles (Cit-AgNPs) is proposed for the detection of Thiophanate-methyl (TM) with high sensitivity and selectivity. The method based on the color change of Cit-AgNPs from yellow to cherry red with the addition of TM to Cit-AgNPs that caused a red-shift on the surface plasmon resonance (SPR) band from 394 nm to 525 nm due to the hydrogen-bonding and substitution. The density functional theory (DFT) method was also calculated the interactions between the TM and citrate ions. Under the optimized conditions, a linear relationship between the absorption ratio (A525nm/A394nm) and TM concentration was found in the range of 2-100 μM with correlation coefficient (R2) of 0.988. The detection limit of TM was 0.12 μM by UV-vis spectrometer. Moreover, the applicability of colorimetric sensor is successfully verified by the detection of TM in environmental samples with good recoveries.

  12. Association of a Human FABP1 Gene Promoter Region Polymorphism with Altered Serum Triglyceride Levels.

    Directory of Open Access Journals (Sweden)

    Xian-E Peng

    Full Text Available Liver fatty acid-binding protein (L-FABP, also known as fatty acid-binding protein 1 (FABP1, is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182 from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032.Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05. The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01. In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = -0.320, P = 0.003, while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014. Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans.

  13. Human serum promotes osteogenic differentiation of human dental pulp stem cells in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Alessandra Pisciotta

    Full Text Available Human dental pulp is a promising alternative source of stem cells for cell-based tissue engineering in regenerative medicine, for the easily recruitment with low invasivity for the patient and for the self-renewal and differentiation potential of cells. So far, in vitro culture of mesenchymal stem cells is usually based on supplementing culture and differentiation media with foetal calf serum (FCS. FCS is known to contain a great quantity of growth factors, and thus to promote cell attachment on plastic surface as well as expansion and differentiation. Nevertheless, FCS as an animal origin supplement may represent a potential means for disease transmission besides leading to a xenogenic immune response. Therefore, a significant interest is focused on investigating alternative supplements, in order to obtain a sufficient cell number for clinical application, avoiding the inconvenients of FCS use. In our study we have demonstrated that human serum (HS is a suitable alternative to FCS, indeed its addition to culture medium induces a high hDPSCs proliferation rate and improves the in vitro osteogenic differentiation. Furthermore, hDPSCs-collagen constructs, pre-differentiated with HS-medium in vitro for 10 days, when implanted in immunocompromised rats, are able to restore critical size parietal bone defects. Therefore these data indicate that HS is a valid substitute for FCS to culture and differentiate in vitro hDPSCs in order to obtain a successful bone regeneration in vivo.

  14. Molecular displacement of warfarin from human serum albumin by flavonoid aglycones

    International Nuclear Information System (INIS)

    Poór, Miklós; Li, Yin; Kunsági-Máté, Sándor; Petrik, József; Vladimir-Knežević, Sanda; Kőszegi, Tamás

    2013-01-01

    The well-known 4-hydroxycoumarin derivative warfarin is a widespread anticoagulant drug. Besides its strong albumin binding property warfarin has a narrow therapeutic window. Therefore, a few percent of displacement from albumin can result in serious biological consequences. The flavonoid molecular group also shows very strong plasma albumin binding characteristics occupying the same binding site. It is plausible to hypothesize that flavonoid aglycones may be able to displace warfarin from human serum albumin (HSA). In our study the competing activities of different flavone (acacetin, apigenin, chrysin, luteolin), flavonol (galangin, quercetin) and flavanone (hesperetin, naringenin) aglycones were investigated using fluorescence spectroscopy. Our results represent that flavonoids are able to displace warfarin from the surface of HSA. On the other hand, when comparing flavone or flavonol groups to flavanones the latter group seems to be much weaker competitor. These observations were also supported by calculation of stability constants. Our investigations strongly suggest that we should reckon with the described molecular displacement. However, further in vivo studies are needed to support the findings of our model system. -- Highlights: • Various flavonoids are able to displace warfarin from human serum albumin. • Flavones and flavonols are much more effective competitors than flavanones. • Even 300 nM aglycone concentrations show the interaction with 3 μM warfarin. • Flavonoid pairs show quasi-additive desorbing property. • Flavones and flavonols are much stronger competitors than the examined drugs

  15. Molecular displacement of warfarin from human serum albumin by flavonoid aglycones

    Energy Technology Data Exchange (ETDEWEB)

    Poór, Miklós [Institute of Laboratory Medicine, University of Pécs, Pécs H-7624 (Hungary); Li, Yin; Kunsági-Máté, Sándor [Department of General and Physical Chemistry, University of Pécs, Pécs H-7624 (Hungary); János Szentágothai Research Center, H-7624 Pécs (Hungary); Petrik, József [Department of Medical Biochemistry and Hematology, Faculty of Pharmacy and Biochemistry, University of Zagreb, HR-10000 Zagreb (Croatia); Vladimir-Knežević, Sanda [Department of Pharmacognosy, Faculty of Pharmacy and Biochemistry, University of Zagreb, HR-10000 Zagreb (Croatia); Kőszegi, Tamás, E-mail: koszegit@freemail.hu [Institute of Laboratory Medicine, University of Pécs, Pécs H-7624 (Hungary)

    2013-10-15

    The well-known 4-hydroxycoumarin derivative warfarin is a widespread anticoagulant drug. Besides its strong albumin binding property warfarin has a narrow therapeutic window. Therefore, a few percent of displacement from albumin can result in serious biological consequences. The flavonoid molecular group also shows very strong plasma albumin binding characteristics occupying the same binding site. It is plausible to hypothesize that flavonoid aglycones may be able to displace warfarin from human serum albumin (HSA). In our study the competing activities of different flavone (acacetin, apigenin, chrysin, luteolin), flavonol (galangin, quercetin) and flavanone (hesperetin, naringenin) aglycones were investigated using fluorescence spectroscopy. Our results represent that flavonoids are able to displace warfarin from the surface of HSA. On the other hand, when comparing flavone or flavonol groups to flavanones the latter group seems to be much weaker competitor. These observations were also supported by calculation of stability constants. Our investigations strongly suggest that we should reckon with the described molecular displacement. However, further in vivo studies are needed to support the findings of our model system. -- Highlights: • Various flavonoids are able to displace warfarin from human serum albumin. • Flavones and flavonols are much more effective competitors than flavanones. • Even 300 nM aglycone concentrations show the interaction with 3 μM warfarin. • Flavonoid pairs show quasi-additive desorbing property. • Flavones and flavonols are much stronger competitors than the examined drugs.

  16. Enzyme-free colorimetric detection systems based on the DNA strand displacement competition reaction

    Science.gov (United States)

    Zhang, Z.; Birkedal, V.; Gothelf, K. V.

    2016-05-01

    The strand displacement competition assay is based on the dynamic equilibrium of the competitive hybridization of two oligonucleotides (A and B) to a third oligonucleotide (S). In the presence of an analyte that binds to a specific affinity-moiety conjugated to strand B, the equilibrium shifts, which can be detected by a shift in the fluorescence resonance energy transfer signal between dyes attached to the DNA strands. In the present study we have integrated an ATP aptamer in the strand B and demonstrated the optical detection of ATP. Furthermore we explore a new readout method using a split G-quadruplex DNAzyme for colorimetric readout of the detection of streptavidin by the naked eye. Finally, we integrate the whole G-quadruplex DNAzyme system in a single DNA strand and show that it is applicable to colorimetric detection.

  17. Enzyme-free colorimetric detection systems based on the DNA strand displacement competition reaction

    DEFF Research Database (Denmark)

    Zhang, Zhao; Birkedal, Victoria; Gothelf, Kurt Vesterager

    2016-01-01

    The strand displacement competition assay is based on the dynamic equilibrium of the competitive hybridization of two oligonucleotides (A and B) to a third oligonucleotide (S). In the presence of an analyte that binds to a specific affinity-moiety conjugated to strand B, the equilibrium shifts, w...... G-quadruplex DNAzyme for colorimetric readout of the detection of streptavidin by the naked eye. Finally, we integrate the whole G-quadruplex DNAzyme system in a single DNA strand and show that it is applicable to colorimetric detection......., which can be detected by a shift in the fluorescence resonance energy transfer signal between dyes attached to the DNA strands. In the present study we have integrated an ATP aptamer in the strand B and demonstrated the optical detection of ATP. Furthermore we explore a new readout method using a split...

  18. Simple and rapid LC-MS/MS method for the absolute determination of cetuximab in human serum using an immobilized trypsin.

    Science.gov (United States)

    Shibata, Kaito; Naito, Takafumi; Okamura, Jun; Hosokawa, Seiji; Mineta, Hiroyuki; Kawakami, Junichi

    2017-11-30

    Proteomic approaches using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) without an immunopurification technique have not been applied to the determination of serum cetuximab. This study developed a simple and rapid LC-MS/MS method for the absolute determination of cetuximab in human serum and applied it to clinical settings. Surrogate peptides derived from cetuximab digests were selected using a Fourier transform mass spectrometer. Reduced-alkylated serum cetuximab without immunopurification was digested for 20minutes using immobilized trypsin, and the digestion products were purified by solid-phase extraction. The LC-MS/MS was run in positive ion multiple reaction monitoring mode. This method was applied to the determination of serum samples in head and neck cancer patients treated with cetuximab. The chromatographic run time was 10minutes and no peaks interfering with surrogate peptides in serum digestion products were observed. The calibration curve of absolute cetuximab in serum was linear over the concentration range of 4-200μg/mL. The lower limit of quantification of cetuximab in human serum was 4μg/mL. The intra-assay and inter-assay precision and accuracy were less than 13.2% and 88.0-100.7%, respectively. The serum concentration range of cetuximab was 19-140μg/mL in patients. The serum cetuximab concentrations in LC-MS/MS were correlated with those in ELISA (r=0.899, P <0.01) and the mean bias was 1.5% in cancer patients. In conclusion, the present simple and rapid method with acceptable analytical performance can be helpful for evaluating the absolute concentration of serum cetuximab in clinical settings. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Competitive protein adsorption to polymer surface from human serum

    DEFF Research Database (Denmark)

    Holmberg, Maria; Jensen, Karin Bagger Stibius; Larsen, Niels Bent

    2008-01-01

    Surface modification by "soft" plasma polymerisation to obtain a hydrophilic and non-fouling polymer surface has been validated using radioactive labelling. Adsorption to unmodified and modified polymer surfaces, from both single protein and human serum solutions, has been investigated. By using...... different radioisotopes, albumin and Immunoglobulin G (IgG) adsorption has been monitored simultaneously during competitive adsorption processes, which to our knowledge has not been reported in the literature before. Results show that albumin and IgG adsorption is dependent on adsorption time...... and on the presence and concentration of other proteins in bulk solutions during adsorption. Generally, lower albumin and IgG adsorption was observed on the modified and more hydrophilic polymer surfaces, but otherwise the modified and unmodified polymer surfaces showed the same adsorption characteristics....

  20. Forster resonance energy transfer in the system of human serum albumin-xanthene dyes

    Science.gov (United States)

    Kochubey, V. I.; Pravdin, A. B.; Melnikov, A. G.; Konstantinova, I.; Alonova, I. V.

    2016-04-01

    The processes of interaction of fluorescent probes: eosin and erythrosine with human serum albumin (HSA) were studied by the methods of absorption and fluorescence spectroscopy. Extinction coefficients of probes were determined. Critical transfer radius and the energy transfer efficiency were defined by fluorescence quenching of HSA. Analysis of the excitation spectra of HSA revealed that the energy transfer process is carried out mainly between tryptophanyl and probes.

  1. Colorimetric detection of Cd"2"+ using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles

    International Nuclear Information System (INIS)

    Huang, Pengcheng; Liu, Bowen; Jin, Weiwei; Wu, Fangying; Wan, Yiqun

    2016-01-01

    A colorimetric assay has been developed for facile, rapid, and sensitive detection of Cd"2"+ using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles (ANS-AgNPs). The presence of Cd"2"+ induces the aggregation of ANS-AgNPs through cooperative metal–ligand interaction. As a result, the characteristic surface plasmon resonance (SPR) peak of ANS-AgNPs at 390 nm was red-shifted to 580 nm, yielding a color change from bright yellow to reddish-brown. The color change is monitored by UV–Vis spectrometer and can be directly read out by the naked eye. Under the optimized conditions, a good linear relationship (correlation coefficient R = 0.997) was obtained between the ratio of the absorbance at 580 nm to that at 390 nm (A_5_8_0_n_m/A_3_9_0_n_m) and the concentration of Cd"2"+ over the range of 1.0–10 μM with detection limit of 87 nM. The proposed method is simple and efficient, which has been applied for determining Cd"2"+ in milk powder, serum, and lake water with satisfactory results.

  2. Determination of trace amounts of hydroperoxides by column liquid chromatography and colorimetric detection

    NARCIS (Netherlands)

    Deelder, R.S.; Kroll, M.; van den Berg, J.H.M.

    1976-01-01

    The sensitive and selective determination of separated compounds in effluents from liquid chromatographic columns can be carried out by continuously adding a suitable colorimetric agent to the column effluent and continuously monitoring the absorbance of the reaction mixture. However, a considerable

  3. Tocopherol isomer pattern in serum and stool of human following consumption of black currant seed press residue administered in whole grain bread.

    Science.gov (United States)

    Helbig, Dorit; Wagner, Andreas; Schubert, Rainer; Jahreis, Gerhard

    2009-12-01

    Serum gamma-tocopherol is thought to be associated with human health. The dietary influence of tocopherol and fibre-rich black currant seed press residue on serum and stool tocopherol concentration was investigated in a controlled human intervention study. Thirty-six women consumed bread enriched with black currant press residue (4 weeks). The resultant faecal and serum tocopherol concentrations were compared with those after a period consuming control bread without press residue and a normal baseline diet. Fibre intake and excretion, antioxidant capacity (TEAC), and vitamin C concentrations in serum and urine were also determined. Samples were obtained with a 5-day standardised diet at the end of each period. The press residue bread lead to significantly increased beta-, gamma-, delta- and total tocopherol intake, serum alpha-, beta-, gamma- and total tocopherol concentration (with and without lipid adjustment), fibre intake and urinary vitamin C concentration compared to control bread (Pconsumption could be due to a presumed interruption of the enzymatic tocopherol degradation mechanism by bread constituents.

  4. Determination of fluvoxamine maleate in human urine and human serum using alkaline KMnO4 -rhodamine B chemiluminescence.

    Science.gov (United States)

    Yang, Dongqin; He, Yanyan; Chen, Funan

    2017-09-01

    The flow-injection chemiluminescence (FI-CL) behavior of a gold nanocluster (Au NC)-enhanced rhodamine B-KMnO 4 system was studied under alkaline conditions for the first time. In the present study, the as-prepared bovine serum albumin-stabilized Au NCs showed excellent stability and reproducibility. The addition of trace levels of fluvoxamine maleate (Flu) led to an obvious decline in CL intensity in the rhodamine B-KMnO 4 -Au NCs system, which could be used for quantitative detection of Flu. Under optimized conditions, the proposed CL system exhibited a favorable analytical performance for Flu determination in the range 2 to 100 μg ml -1 . The detection limit for Flu measurement was 0.021 μg ml -1 . Moreover, this newly developed system revealed outstanding selectivity for Flu detection when compared with a multitude of other species, such as the usual ions, uric acid and a section of hydroxy compounds. Additionally, CL spectra, UV-visible spectroscopes and fluorescence spectra were measured in order to determine the possible reaction mechanism. This approach could be used to detect Flu in human urine and human serum samples with the desired recoveries and could have promising application under physiological conditions. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Multiple isoforms of the human pentraxin serum amyloid P component

    DEFF Research Database (Denmark)

    Sørensen, Inge Juul; Andersen, Ove; Nielsen, EH

    1995-01-01

    Human serum amyloid P component (SAP) isolated from 20 healthy individuals was analyzed by anion exchange chromatography and isoelectric focusing (IEF) in order to investigate the existence of multiple forms of SAP and interindividual structural differences. Anion exchange chromatography showed one...... major and several minor subpopulations of SAP. IEF of all SAP isolates showed a previously unreported degree of heterogeneity with six isoelectric forms (pKi range 5.5-6.1) and with minor interindividual differences in respect of isoelectric points. Total enzymatic deglycosylation of SAP reduced...... the number of bands in IEF to two indicating the existence of two types of polypeptide chains....

  6. Quantitation of 14C-oxaliplatin concentrations in human serum samples by using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Kobayashi, Takeshi; Toyoguchi, Teiko; Kato, Kazuhiro; Tokanai, Fuyuki; Shiraishi, Tadashi

    2013-01-01

    The understanding of human pharmacokinetics is important for development of new drugs. Microdosing studies have been proposed as means of obtaining human pharmacokinetics information at early stages of drug development. Accelerator mass spectrometry (AMS) has high detection sensitivity and is expected to play an important role in microdose trials. In this study, we used the AMS microdosing facility at Yamagata University to measure the concentration of 14 C in 14 C-oxaliplatin-spiked serum samples. The calibration curve of 14 C concentration in serum was linear, and the correlation coefficient was 0.9994. The precision, accuracy, and stability values obtained (freeze and thaw cycles, and short- and long-term stability) satisfied the criteria. The mean background 14 C concentrations in samples of 6 healthy Japanese volunteers were 1.635dpm/mL in blood and 0.56dpm/mL in plasma. These results suggest the suitability of AMS-based quantitation for analyzing samples from microdosing studies. (author)

  7. Epitope imprinted polymer nanoparticles containing fluorescent quantum dots for specific recognition of human serum albumin

    International Nuclear Information System (INIS)

    Wang, Yi-Zhi; Li, Dong-Yan; He, Xi-Wen; Li, Wen-You; Zhang, Yu-Kui

    2015-01-01

    Epitope imprinted polymer nanoparticles (EI-NPs) were prepared by one-pot polymerization of N-isopropylacrylamide in the presence of CdTe quantum dots and an epitope (consisting of amino acids 598 to 609) of human serum albumin (HSA). The resulting EI-NPs exhibit specific recognition ability and enable direct fluorescence quantification of HSA based on a fluorescence turn-on mode. The polymer was characterized by FT-IR, X-ray photoelectron spectroscopy, transmission electron microscopy and dynamic light scattering. The linear calibration graph was obtained in the range of 0.25–5 μmol · mL −1 with the detection limit of 44.3 nmol · mL −1 . The EI-NPs were successfully applied to the direct fluorometric quantification of HSA in samples of human serum. Overall, this approach provides a promising tool to design functional fluorescent materials with protein recognition capability and specific applications in proteomics. (author)

  8. Multiple free-radical scavenging (MULTIS) capacity in cattle serum.

    Science.gov (United States)

    Sueishi, Yoshimi; Kamogawa, Erisa; Kimura, Anna; Kitahara, Go; Satoh, Hiroyuki; Asanuma, Taketoshi; Oowada, Shigeru

    2017-01-01

    Multiple free-radical scavenging (MULTIS) activity in cattle and human sera was evaluated with electron spin resonance spectroscopy. Scavenging rates against six active species, namely hydroxyl radical, superoxide anion, alkoxyl radical, alkylperoxyl radical, methyl radical, and singlet oxygen were quantified. The difference in the electron spin resonance signal intensity in the presence and absence of the serum was converted into the scavenging rates. Comparative MULTIS measurements were made in sera from eight beef cattle, three fetal calves and fifteen healthy human volunteers. Further, we determined the MULTIS value of albumin, the most abundant component in serum. MULTIS values in cattle sera indicated higher scavenging activity against most free radical species tested than human sera. In particular, cattle serum scavenging activities against superoxide and methyl radical were higher than human serum by 2.6 and 3.7 fold, respectively. In cattle serum, albumin appears to play a dominant role in MULTIS activity, but in human serum that is not the case. Previous data indicated that the abundance of uric acid in bovine blood is nearly 80% less than humans; however, this difference does not explain the deviation in MULTIS profile.

  9. Human serum albumin crystals and method of preparation

    Science.gov (United States)

    Carter, Daniel C. (Inventor)

    1989-01-01

    Human serum albumin (HSA) crystals are provided in the form of tetragonal plates having the space groups P42(sub 1)2, the crystals being grown to sizes in excess of 0.5 mm in two dimensions and a thickness of 0.1 mm. Growth of the crystals is carried out by a hanging drop method wherein a precipitant solution containing polyethylene glycol (PEG) and a phosphate buffer is mixed with an HSA solution, and a droplet of mixed solution is suspended over a well of precipitant solution. Crystals grow to the desired size in 3 to 7 days. Concentration of reagents, pH and other parameters are controlled within prescribed limits. The resulting crystals exhibit a size and quality such as to allow performance of x ray diffraction studies and enable the conduct of drug binding studies as well as genetic engineering studies.

  10. Thermometric enzyme linked immunosorbent assay in continuous flow system: optimization and evaluation using human serum albumin as a model system.

    Science.gov (United States)

    Borrebaeck, C; Börjeson, J; Mattiasson, B

    1978-06-15

    Thermometric enzyme-linked immunosorbent assay (TELISA) is described. After the procedure of optimization, human serum albumin was assayed using anti-human serum albumin bound to Sepharose CL 4-B in the enzyme thermistor unit and catalase as label on the free antigen. The model system was used for assays down to 10(-13)M and the preparation of immobilized antibodies was used repeatedly up to 100 times. Comparative studies of the TELISA technique with bromocresol green, immunoturbidimetric and rocket immunoelectrophoretic methods were carried out and showed that TELISA could be used as an alternative method.

  11. Cabazitaxel-loaded human serum albumin nanoparticles as a therapeutic agent against prostate cancer

    Directory of Open Access Journals (Sweden)

    Qu N

    2016-07-01

    Full Text Available Na Qu,1 Robert J Lee,1,2 Yating Sun,1 Guangsheng Cai,1 Junyang Wang,1 Mengqiao Wang,1 Jiahui Lu,1 Qingfan Meng,1 Lirong Teng,1 Di Wang,1 Lesheng Teng1,3 1School of Life Sciences, Jilin University, Changchun, People’s Republic of China; 2Division of Pharmaceutics, College of Pharmacy, The Ohio State University, Columbus, OH, USA; 3State Key Laboratory of Long-acting and Targeting Drug Delivery System, Yantai, People’s Republic of China Abstract: Cabazitaxel-loaded human serum albumin nanoparticles (Cbz-NPs were synthesized to overcome vehicle-related toxicity of current clinical formulation of the drug based on Tween-80 (Cbz-Tween. A salting-out method was used for NP synthesis that avoids the use of chlorinated organic solvent and is simpler compared to the methods based on emulsion-solvent evaporation. Cbz-NPs had a narrow particle size distribution, suitable drug loading content (4.9%, and superior blood biocompatibility based on in vitro hemolysis assay. Blood circulation, tumor uptake, and antitumor activity of Cbz-NPs were assessed in prostatic cancer xenograft-bearing nude mice. Cbz-NPs exhibited prolonged blood circulation and greater accumulation of Cbz in tumors along with reduced toxicity compared to Cbz-Tween. Moreover, hematoxylin and eosin histopathological staining of organs revealed consistent results. The levels of blood urea nitrogen and serum creatinine in drug-treated mice showed that Cbz-NPs were less toxic than Cbz-Tween to the kidneys. In conclusion, Cbz-NPs provide a promising therapeutic for prostate cancer. Keywords: cabazitaxel, human serum albumin, nanoparticle, drug delivery, toxicity, pros­tate cancer

  12. INCREASED MATERNAL SERUM ALPHA-FETOPROTEIN AND HUMAN CHORIONIC-GONADOTROPIN IN COMPROMISED PREGNANCIES OTHER THAN FOR NEURAL-TUBE DEFECTS OR DOWN-SYNDROME

    NARCIS (Netherlands)

    BEEKHUIS, [No Value; VANLITH, JMM; DEWOLF, BTHM; MANTINGH, A

    Intrauterine fetal death occurred in four women who were 'screen-positive' in a screening programme for neural tube defects (NTDs) and Down syndrome (DS). These women had very high levels of maternal serum alpha-fetoprotein (MSAFP) and maternal serum human chorionic gonadotropin (MShCG). Therefore,

  13. A fast, sensitive and easy colorimetric assay for chitinase and cellulase activity detection.

    NARCIS (Netherlands)

    Ferrari, Alessandro; Gaber, Yasser; Fraaije, Marco

    2014-01-01

    BACKGROUND: Most of the current colorimetric methods for detection of chitinase or cellulase activities on the insoluble natural polymers chitin and cellulose depend on a chemical redox reaction. The reaction involves the reducing ends of the hydrolytic products. The Schales' procedure and the

  14. A rapid colorimetric assay for mold spore germination using XTT tetrazolium salt

    Science.gov (United States)

    Carol A. Clausen; Vina W. Yang

    2011-01-01

    Current laboratory test methods to measure efficacy of new mold inhibitors are time consuming, some require specialized test equipment and ratings are subjective. Rapid, simple quantitative assays to measure the efficacy of mold inhibitors are needed. A quantitative, colorimetric microassay was developed using XTT tetrazolium salt to metabolically assess mold spore...

  15. Colorimetric Recognition of Aldehydes and Ketones.

    Science.gov (United States)

    Li, Zheng; Fang, Ming; LaGasse, Maria K; Askim, Jon R; Suslick, Kenneth S

    2017-08-07

    A colorimetric sensor array has been designed for the identification of and discrimination among aldehydes and ketones in vapor phase. Due to rapid chemical reactions between the solid-state sensor elements and gaseous analytes, distinct color difference patterns were produced and digitally imaged for chemometric analysis. The sensor array was developed from classical spot tests using aniline and phenylhydrazine dyes that enable molecular recognition of a wide variety of aliphatic or aromatic aldehydes and ketones, as demonstrated by hierarchical cluster, principal component, and support vector machine analyses. The aldehyde/ketone-specific sensors were further employed for differentiation among and identification of ten liquor samples (whiskies, brandy, vodka) and ethanol controls, showing its potential applications in the beverage industry. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Discrimination of honeys using colorimetric sensor arrays, sensory analysis and gas chromatography techniques.

    Science.gov (United States)

    Tahir, Haroon Elrasheid; Xiaobo, Zou; Xiaowei, Huang; Jiyong, Shi; Mariod, Abdalbasit Adam

    2016-09-01

    Aroma profiles of six honey varieties of different botanical origins were investigated using colorimetric sensor array, gas chromatography-mass spectrometry (GC-MS) and descriptive sensory analysis. Fifty-eight aroma compounds were identified, including 2 norisoprenoids, 5 hydrocarbons, 4 terpenes, 6 phenols, 7 ketones, 9 acids, 12 aldehydes and 13 alcohols. Twenty abundant or active compounds were chosen as key compounds to characterize honey aroma. Discrimination of the honeys was subsequently implemented using multivariate analysis, including hierarchical clustering analysis (HCA) and principal component analysis (PCA). Honeys of the same botanical origin were grouped together in the PCA score plot and HCA dendrogram. SPME-GC/MS and colorimetric sensor array were able to discriminate the honeys effectively with the advantages of being rapid, simple and low-cost. Moreover, partial least squares regression (PLSR) was applied to indicate the relationship between sensory descriptors and aroma compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Measurements of vitamin B12 in human blood serum using resonance Raman spectroscopy

    Science.gov (United States)

    Tsiminis, G.; Schartner, E. P.; Brooks, J. L.; Hutchinson, M. R.

    2016-12-01

    Vitamin B12 (cobalamin and its derivatives) deficiency has been identified as a potential modifiable risk factor for dementia and Alzheimer's disease. Chronic deficiency of vitamin B12 has been significantly associated with an increased risk of cognitive decline. An effective and efficient method for measuring vitamin B12 concentration in human blood would enable ongoing tracking and assessment of this potential modifiable risk factor. In this work we present an optical sensor based on resonance Raman spectroscopy for rapid measurements of vitamin B12 in human blood serum. The measurement takes less than a minute and requires minimum preparation (centrifuging) of the collected blood samples.

  18. A rapid colorimetric screening method for vanillic acid and vanillin-producing bacterial strains.

    Science.gov (United States)

    Zamzuri, N A; Abd-Aziz, S; Rahim, R A; Phang, L Y; Alitheen, N B; Maeda, T

    2014-04-01

    To isolate a bacterial strain capable of biotransforming ferulic acid, a major component of lignin, into vanillin and vanillic acid by a rapid colorimetric screening method. For the production of vanillin, a natural aroma compound, we attempted to isolate a potential strain using a simple screening method based on pH change resulting from the degradation of ferulic acid. The strain Pseudomonas sp. AZ10 UPM exhibited a significant result because of colour changes observed on the assay plate on day 1 with a high intensity of yellow colour. The biotransformation of ferulic acid into vanillic acid by the AZ10 strain provided the yield (Yp/s ) and productivity (Pr ) of 1·08 mg mg(-1) and 53·1 mg L(-1) h(-1) , respectively. In fact, new investigations regarding lignin degradation revealed that the strain was not able to produce vanillin and vanillic acid directly from lignin; however, partially digested lignin by mixed enzymatic treatment allowed the strain to produce 30·7 mg l(-1) and 1·94 mg l(-1) of vanillic acid and biovanillin, respectively. (i) The rapid colorimetric screening method allowed the isolation of a biovanillin producer using ferulic acid as the sole carbon source. (ii) Enzymatic treatment partially digested lignin, which could then be utilized by the strain to produce biovanillin and vanillic acid. To the best of our knowledge, this is the first study reporting the use of a rapid colorimetric screening method for bacterial strains producing vanillin and vanillic acid from ferulic acid. © 2013 The Society for Applied Microbiology.

  19. Effect of continuous recombinant human endostatin pumping combined with TP chemotherapy on serum malignant molecules and angiogenesis molecules in patients with advanced ovarian cancer

    Directory of Open Access Journals (Sweden)

    Wei-Dong Chen

    2017-05-01

    Full Text Available Objective: To study the effect of continuous recombinant human endostatin pumping combined with TP chemotherapy on serum malignant molecules and angiogenesis molecules in patients with advanced ovarian cancer. Methods: 78 patients with advanced ovarian cancer who were treated in our hospital between July 2011 and December 2015 were selected and divided into observation group and control group (n=39 according to the single-blind randomized control method. Before treatment and after 4 cycles of treatment, electrochemical luminescence immunity analyzer was used to detect serum tumor marker levels; RIA method was used to determine serum apoptosis molecule levels; enzyme-linked immunosorbent assay (ELISA was used to detect the serum angiogenesis molecule levels. Results: Before treatment, differences in serum levels of tumor markers, apoptosis molecules and angiogenesis molecules were not statistically significant between two groups of patients (P>0.05. After 4 cycles of treatment, serum carbohydrate antigen 125 (CA125, carbohydrate antigen 153 (CA153, human epididymis protein 4 (HE4, carcinoembryonic antigen (CEA, human chorionic gonadotropin (β-HCG, Bcl-2, Survivin, Bag-1, angiogenin-2 (Ang-2, vascular endothelial growth factor (VEGF and basic fibroblast growth factor (bFGF levels of observation group were significantly lower than those of control group (P<0.05 while Bax level was significantly higher than that of control group (P<0.05. Conclusions: Continuous recombinant human endostatin pumping combined with TP chemotherapy can decrease the malignant degree of advanced ovarian cancer and inhibit angiogenesis.

  20. Bile acids induce arrhythmias in human atrial myocardium--implications for altered serum bile acid composition in patients with atrial fibrillation.

    Science.gov (United States)

    Rainer, Peter P; Primessnig, Uwe; Harenkamp, Sandra; Doleschal, Bernhard; Wallner, Markus; Fauler, Guenter; Stojakovic, Tatjana; Wachter, Rolf; Yates, Ameli; Groschner, Klaus; Trauner, Michael; Pieske, Burkert M; von Lewinski, Dirk

    2013-11-01

    High bile acid serum concentrations have been implicated in cardiac disease, particularly in arrhythmias. Most data originate from in vitro studies and animal models. We tested the hypotheses that (1) high bile acid concentrations are arrhythmogenic in adult human myocardium, (2) serum bile acid concentrations and composition are altered in patients with atrial fibrillation (AF) and (3) the therapeutically used ursodeoxycholic acid has different effects than other potentially toxic bile acids. Multicellular human atrial preparations ('trabeculae') were exposed to primary bile acids and the incidence of arrhythmic events was assessed. Bile acid concentrations were measured in serum samples from 250 patients and their association with AF and ECG parameters analysed. Additionally, we conducted electrophysiological studies in murine myocytes. Taurocholic acid (TCA) concentration-dependently induced arrhythmias in atrial trabeculae (14/28 at 300 µM TCA, pursodeoxycholic acid did not. Patients with AF had significantly decreased serum levels of ursodeoxycholic acid conjugates and increased levels of non-ursodeoxycholic bile acids. In isolated myocytes, TCA depolarised the resting membrane potential, enhanced Na(+)/Ca(2+) exchanger (NCX) tail current density and induced afterdepolarisations. Inhibition of NCX prevented arrhythmias in atrial trabeculae. High TCA concentrations induce arrhythmias in adult human atria while ursodeoxycholic acid does not. AF is associated with higher serum levels of non-ursodeoxycholic bile acid conjugates and low levels of ursodeoxycholic acid conjugates. These data suggest that higher levels of toxic (arrhythmogenic) and low levels of protective bile acids create a milieu with a decreased arrhythmic threshold and thus may facilitate arrhythmic events.

  1. Optical sensing of sulfate by polymethinium salt receptors: colorimetric sensor for heparin

    Czech Academy of Sciences Publication Activity Database

    Bříza, T.; Kejík, Z.; Císařová, I.; Králová, Jarmila; Martásek, P.; Král, V.

    2008-01-01

    Roč. 16, - (2008), s. 1901-1903 ISSN 1359-7345 R&D Projects: GA AV ČR KAN200200651; GA ČR(CZ) GA203/06/1038 Institutional research plan: CEZ:AV0Z50520514 Keywords : colorimetric sensor * heparin * polymethinium salt Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.340, year: 2008

  2. Serum 3,3'-L-diiodothyronine, a direct radioimmunoassay in human serum: method and clinical results

    International Nuclear Information System (INIS)

    Burger, A.; Sakoloff, C.

    1977-01-01

    A specific radioimmunoassay for 3,3'-diiodothyronine (T 2 ) is described which is capable of detecting as little as 1.3 ng/dl. The antiserum recognizes mainly T 2 ; biliary conjugates of T 2 bind slightly to the antibody. The intraassay and interassay coefficients of variation were, respectively, 5.7% and 13.1%. T 2 was detected in the serum of hypothyroid patients treated with triiodothyronine (T 3 ) and in euthyroid subjects treated with reverse triiodothyronine (rT 3 ). These results suggest that both T 3 and rT 3 are deiodinated to T 2 . Serum concentrations of T 2 in normal subjects decreased with age. Between 20 and 40 years the mean concentration was 4.3 +- 2.0 ng/dl (2 SD), between 41 and 60 years it varied from 1.9 to 5.8 ng/dl (3.8 +- 0.3 ng/dl, SE) and in elderly subjects have 60 years concentrations varied from unmeasurable to 4 ng/dl (2.9 +- 0.4 ng/dl, SE). Low serum T 2 concentrations were found in anorexia nervosa (2.5 +- 0.3 ng/dl, SE). In hypothyroidism the serum concentrations were low or unmeasurable. As most of the hypothyroid subjects were elderly their serum T 2 concentrations overlapped with the low values found in the elderly euthyroid subjects. In classical hyperthyroidism serum T 2 concentrations were greatly increased (3.3 to 31 ng/dl (11.8 +- 2.7 ng/dl, SE) but in ''T 3 toxicosis'' the concentrations were only modestly increased

  3. Ischemic stroke progress evaluation by {sup 31}P NMR-based metabonomic of human serum

    Energy Technology Data Exchange (ETDEWEB)

    Grandizoli, Caroline W.P.S.; Barison, Andersson, E-mail: andernmr@ufpr.br [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Departamento de Quimica. Centro de RMN; Lange, Marcos C.; Novak, Felipe T. M. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Hospital de Clínicas. Divisao de Neurologia; Campos, Francinete R. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Departmento de Farmacia

    2014-07-01

    In this work, chemometric analyses over {sup 31}P{"1"H} NMR (nuclear magnetic resonance) spectra of human blood serum permitted to discriminated ischemic stroke patients from health individuals due to changes in the chemical composition of phosphorus-containing compounds. These results indicate that {sup 31}P NMR-based metabonomic allowed insights over the mechanism triggered by ischemic stroke. (author)

  4. Multi-colorimetric sensor array for detection of illegal materials

    DEFF Research Database (Denmark)

    Kostesha, Natalie; Boisen, Anja; Jakobsen, Mogens Havsteen

    2012-01-01

    The detection of low pressure illegal compounds is an important analytical problem which requires reliable, selective and sensitive detection methods which provide the highest level of confidence in the result. Therefore, to contribute in the successful development of the recognition technology...... and signal processing enhancements to sensing methods, recognition ability, data acquisition time and data processing algorithms are necessary. In this research we work towards the development of a rapid, easy in use, highly sensitive, specific (minimal false positives) sensor based on a colorimetric sensing...

  5. On-site preparation of technetium-99m labeled human serum albumin for clinical application

    International Nuclear Information System (INIS)

    Wang Yuhfeng; Chuang Meihua; Cham Thauming; Chung Meiing; Chiu Jainnshiun

    2007-01-01

    Technetium-99m labeled human serum albumin (Tc-99m HSA) is an important radiopharmaceutical for clinical applications, such as cardiac function tests or protein-losing gastroenteropathy assessment. However, because of transfusion-induced infectious diseases, the safety of serum products is a serious concern. In this context, serum products acquired from patients themselves are the most ideal tracer. However, the development of rapid separation and easy clinical labeling methods is not yet well established. Under such situation, products from the same ethnic group or country are now recommended by the World Health Organization as an alternative preparation. This article describes the on-site preparation of Tc-99m HSA from locally supplied serum products. Different formulations were prepared and the labeling efficiency and stability were examined. Radio-labeling efficiencies were more than 90% in all preparation protocols, except for one that omitted the stannous solution. The most cost-effective protocol contained HSA 0.1 mg, treated with stannous fluoride 0.2 mg, and mixed with Tc-99m pertechnetate 30 mCi. A biodistribution study was performed in rats using a gamma camera immediately after intravenous administration of radiolabeled HSA. Tissue/organ uptake was obtained by measuring the radioactivity in organs after sacrificing the rats at timed intervals. The biologic half-life was about 32 min, determined from sequential venous blood collections. These data indicate that our preparation of Tc-99m HSA is useful and potentially applicable clinically. In addition, this on-site preparation provides the possibility of labeling a patient's own serum for subsequent clinical application. (author)

  6. Immunologic relationships of human serum albumin, macroaggregated albumin, and albumin microspheres

    International Nuclear Information System (INIS)

    Stang, P.C.; Roelands, J.F.; Cohen, P.

    1975-01-01

    Antigenic relationships of NSA (normal serum albumin), MAA (macroaggregated albumin), and HAM (human albumin microspheres) were determined in vivo in guinea pigs and in vitro in gel diffusion plates. Results showed that HAM could sensitize but seldom elicit anaphylaxis when used to challenge guinea pigs. In contrast, NSA and MAA were strong sensitizing antigens and inducers of anaphylaxis. The relative inability of HAM to induce anaphylaxis suggests that during production of the microspheres from soluble albumin, antigenic determinants of albumin may be altered or masked. Consequently, these determinants may be less available to react with antibody at the tissue sites

  7. Urinary Colorimetric Sensor Array and Algorithm to Distinguish Kawasaki Disease from Other Febrile Illnesses.

    Directory of Open Access Journals (Sweden)

    Zhen Li

    Full Text Available Kawasaki disease (KD is an acute pediatric vasculitis of infants and young children with unknown etiology and no specific laboratory-based test to identify. A specific molecular diagnostic test is urgently needed to support the clinical decision of proper medical intervention, preventing subsequent complications of coronary artery aneurysms. We used a simple and low-cost colorimetric sensor array to address the lack of a specific diagnostic test to differentiate KD from febrile control (FC patients with similar rash/fever illnesses.Demographic and clinical data were prospectively collected for subjects with KD and FCs under standard protocol. After screening using a genetic algorithm, eleven compounds including metalloporphyrins, pH indicators, redox indicators and solvatochromic dye categories, were selected from our chromatic compound library (n = 190 to construct a colorimetric sensor array for diagnosing KD. Quantitative color difference analysis led to a decision-tree-based KD diagnostic algorithm.This KD sensing array allowed the identification of 94% of KD subjects (receiver operating characteristic [ROC] area under the curve [AUC] 0.981 in the training set (33 KD, 33 FC and 94% of KD subjects (ROC AUC: 0.873 in the testing set (16 KD, 17 FC. Color difference maps reconstructed from the digital images of the sensing compounds demonstrated distinctive patterns differentiating KD from FC patients.The colorimetric sensor array, composed of common used chemical compounds, is an easily accessible, low-cost method to realize the discrimination of subjects with KD from other febrile illness.

  8. Comparative Serum Challenges Show Divergent Patterns of Gene Expression and Open Chromatin in Human and Chimpanzee.

    Science.gov (United States)

    Pizzollo, Jason; Nielsen, William J; Shibata, Yoichiro; Safi, Alexias; Crawford, Gregory E; Wray, Gregory A; Babbitt, Courtney C

    2018-03-01

    Humans experience higher rates of age-associated diseases than our closest living evolutionary relatives, chimpanzees. Environmental factors can explain many of these increases in disease risk, but species-specific genetic changes can also play a role. Alleles that confer increased disease susceptibility later in life can persist in a population in the absence of selective pressure if those changes confer positive adaptation early in life. One age-associated disease that disproportionately affects humans compared with chimpanzees is epithelial cancer. Here, we explored genetic differences between humans and chimpanzees in a well-defined experimental assay that mimics gene expression changes that happen during cancer progression: A fibroblast serum challenge. We used this assay with fibroblasts isolated from humans and chimpanzees to explore species-specific differences in gene expression and chromatin state with RNA-Seq and DNase-Seq. Our data reveal that human fibroblasts increase expression of genes associated with wound healing and cancer pathways; in contrast, chimpanzee gene expression changes are not concentrated around particular functional categories. Chromatin accessibility dramatically increases in human fibroblasts, yet decreases in chimpanzee cells during the serum response. Many regions of opening and closing chromatin are in close proximity to genes encoding transcription factors or genes involved in wound healing processes, further supporting the link between changes in activity of regulatory elements and changes in gene expression. Together, these expression and open chromatin data show that humans and chimpanzees have dramatically different responses to the same physiological stressor, and how a core physiological process can evolve quickly over relatively short evolutionary time scales.

  9. Molecular interaction of PCB153 to human serum albumin: Insights from spectroscopic and molecular modeling studies

    Energy Technology Data Exchange (ETDEWEB)

    Han, Chao; Fang, Senbiao; Cao, Huiming; Lu, Yan; Ma, Yaqiong [School of Pharmacy, Lanzhou University, Lanzhou 730000 (China); Wei, Dongfeng [Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing 100700 (China); Xie, Xiaoyun [College of Earth and Environmental Science, Lanzhou University, Lanzhou 730000 (China); Liu, Xiaohua [School of Pharmacy, Lanzhou University, Lanzhou 730000 (China); Li, Xin [College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471003 (China); Fei, Dongqing [School of Pharmacy, Lanzhou University, Lanzhou 730000 (China); Zhao, Chunyan, E-mail: zhaochy07@lzu.edu.cn [School of Pharmacy, Lanzhou University, Lanzhou 730000 (China)

    2013-03-15

    Highlights: ► We identify the binding mode of PCB153 to human serum albumin (HSA). ► Spectroscopic and molecular modeling results reveal that PCB153 binds at the site II. ► The interaction is mainly governed by hydrophobic and hydrogen bond forces. ► The work helps to probe transporting, distribution and toxicity effect of PCBs. -- Abstract: Polychlorinated biphenyls (PCBs) possessed much potential hazard to environment because of its chemical stability and biological toxicity. Here, we identified the binding mode of a representative compound, PCB153, to human serum albumin (HSA) using fluorescence and molecular dynamics simulation methods. The fluorescence study showed that the intrinsic fluorescence of HSA was quenched by addition of PCB153 through a static quenching mechanism. The thermodynamic analysis proved the binding behavior was mainly governed by hydrophobic force. Furthermore, as evidenced by site marker displacement experiments using two probe compounds, it revealed that PCB153 acted exactly on subdomain IIIA (site II) of HSA. On the other hand, the molecular dynamics studies as well as free energy calculations made another important contribution to understand the conformational changes of HSA and the stability of HSA-PCB153 system. Molecular docking revealed PCB153 can bind in a large hydrophobic activity of subdomain IIIA by the hydrophobic interaction and hydrogen bond interactions between chlorine atoms and residue ASN391. The present work provided reasonable models helping us further understand the transporting, distribution and toxicity effect of PCBs when it spread into human blood serum.

  10. Determining the binding affinity of therapeutic monoclonal antibodies towards their native unpurified antigens in human serum.

    Directory of Open Access Journals (Sweden)

    Christine Bee

    Full Text Available Monoclonal antibodies (mAbs are a growing segment of therapeutics, yet their in vitro characterization remains challenging. While it is essential that a therapeutic mAb recognizes the native, physiologically occurring epitope, the generation and selection of mAbs often rely on the use of purified recombinant versions of the antigen that may display non-native epitopes. Here, we present a method to measure both, the binding affinity of a therapeutic mAb towards its native unpurified antigen in human serum, and the antigen's endogenous concentration, by combining the kinetic exclusion assay and Biacore's calibration free concentration analysis. To illustrate the broad utility of our method, we studied a panel of mAbs raised against three disparate soluble antigens that are abundant in the serum of healthy donors: proprotein convertase subtilisin/kexin type 9 (PCSK9, progranulin (PGRN, and fatty acid binding protein (FABP4. We also determined the affinity of each mAb towards its purified recombinant antigen and assessed whether the interactions were pH-dependent. Of the six mAbs studied, three did not appear to discriminate between the serum and recombinant forms of the antigen; one mAb bound serum antigen with a higher affinity than recombinant antigen; and two mAbs displayed a different affinity for serum antigen that could be explained by a pH-dependent interaction. Our results highlight the importance of taking pH into account when measuring the affinities of mAbs towards their serum antigens, since the pH of serum samples becomes increasingly alkaline upon aerobic handling.

  11. Determination of colloidal and dissolved silver in water samples using colorimetric solid-phase extraction.

    Science.gov (United States)

    Hill, April A; Lipert, Robert J; Porter, Marc D

    2010-03-15

    The increase in bacterial resistance to antibiotics has led to resurgence in the use of silver as a biocidal agent in applications ranging from washing machine additives to the drinking water treatment system on the International Space Station (ISS). However, growing concerns about the possible toxicity of colloidal silver to bacteria, aquatic organisms and humans have led to recently issued regulations by the US EPA and FDA regarding the usage of silver. As part of an ongoing project, we have developed a rapid, simple method for determining total silver, both ionic (silver(I)) and colloidal, in 0.1-1mg/L aqueous samples, which spans the ISS potable water target of 0.3-0.5mg/L (total silver) and meets the US EPA limit of 0.1mg/L in drinking water. The method is based on colorimetric solid-phase extraction (C-SPE) and involves the extraction of silver(I) from water samples by passage through a solid-phase membrane impregnated with the colorimetric reagent DMABR (5-[4-(dimethylamino)benzylidene]rhodanine). Silver(I) exhaustively reacts with impregnated DMABR to form a colored compound, which is quantified using a handheld diffuse reflectance spectrophotometer. Total silver is determined by first passing the sample through a cartridge containing Oxone, which exhaustively oxidizes colloidal silver to dissolved silver(I). The method, which takes less than 2 min to complete and requires only approximately 1 mL of sample, has been validated through a series of tests, including a comparison with the ICP-MS analysis of a water sample from ISS that contained both silver(I) and colloidal silver. Potential earth-bound applications are also briefly discussed. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  12. BSA-stabilized Pt nanozyme for peroxidase mimetics and its application on colorimetric detection of mercury(II) ions.

    Science.gov (United States)

    Li, Wei; Chen, Bin; Zhang, Haixiang; Sun, Yanhua; Wang, Jun; Zhang, Jinli; Fu, Yan

    2015-04-15

    Bovine serum albumin (BSA) is chosen as the nucleation templates to synthesize Pt-based peroxidase nanomimetics with the average diameter of 2.0nm. The efficient Pt nanozymes consist of 57% Pt(0) and 43% Pt(2+), which possess highly peroxidase-like activity with the Km values of 0.119mM and 41.8mM toward 3,3',5,5'-tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2), respectively. Interestingly, Hg(2+) is able to down-regulate the enzymatic activity of Pt nanoparticles, mainly through the interactions between Hg(2+) and Pt(0). It is the first report to explore a colorimetric Hg(2+) sensing system on the basis of peroxidase mimicking activities of Pt nanoparticles. One of our most intriguing results is that BSA-stabilized Pt nanozymes demonstrate the ability to sense Hg(2+) ions in aqueous solution without significant interference from other metal ions. The Hg(2+) detection limit of 7.2nM is achieved with a linear response range of 0-120nM, and the developed sensing system is potentially applicable for quantitative determination of Hg(2+) in drinking water. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Colorimetric detection of Cd{sup 2+} using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Pengcheng; Liu, Bowen; Jin, Weiwei; Wu, Fangying, E-mail: fywu@ncu.edu.cn; Wan, Yiqun [Nanchang University, College of Chemistry (China)

    2016-11-15

    A colorimetric assay has been developed for facile, rapid, and sensitive detection of Cd{sup 2+} using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles (ANS-AgNPs). The presence of Cd{sup 2+} induces the aggregation of ANS-AgNPs through cooperative metal–ligand interaction. As a result, the characteristic surface plasmon resonance (SPR) peak of ANS-AgNPs at 390 nm was red-shifted to 580 nm, yielding a color change from bright yellow to reddish-brown. The color change is monitored by UV–Vis spectrometer and can be directly read out by the naked eye. Under the optimized conditions, a good linear relationship (correlation coefficient R = 0.997) was obtained between the ratio of the absorbance at 580 nm to that at 390 nm (A{sub 580nm}/A{sub 390nm}) and the concentration of Cd{sup 2+} over the range of 1.0–10 μM with detection limit of 87 nM. The proposed method is simple and efficient, which has been applied for determining Cd{sup 2+} in milk powder, serum, and lake water with satisfactory results.

  14. A duplex DNA-gold nanoparticle probe composed as a colorimetric biosensor for sequence-specific DNA-binding proteins.

    Science.gov (United States)

    Ahn, Junho; Choi, Yeonweon; Lee, Ae-Ree; Lee, Joon-Hwa; Jung, Jong Hwa

    2016-03-21

    Using duplex DNA-AuNP aggregates, a sequence-specific DNA-binding protein, SQUAMOSA Promoter-binding-Like protein 12 (SPL-12), was directly determined by SPL-12-duplex DNA interaction-based colorimetric actions of DNA-Au assemblies. In order to prepare duplex DNA-Au aggregates, thiol-modified DNA 1 and DNA 2 were attached onto the surface of AuNPs, respectively, by the salt-aging method and then the DNA-attached AuNPs were mixed. Duplex-DNA-Au aggregates having the average size of 160 nm diameter and the maximum absorption at 529 nm were able to recognize SPL-12 and reached the equivalent state by the addition of ∼30 equivalents of SPL-12 accompanying a color change from red to blue with a red shift of the maximum absorption at 570 nm. As a result, the aggregation size grew to about 247 nm. Also, at higher temperatures of the mixture of duplex-DNA-Au aggregate solution and SPL-12, the equivalent state was reached rapidly. On the contrary, in the control experiment using Bovine Serum Albumin (BSA), no absorption band shift of duplex-DNA-Au aggregates was observed.

  15. CCQM K6.2 determination of total cholesterol in human serum

    Science.gov (United States)

    Wise, Stephen A.; Phinney, Karen W.; Duewer, David L.; Sniegoski, Lorna T.; Welch, Michael J.; Pabello, Guiomar; Avila Caldero, Marco A.; Qinde, Liu; Kooi, Lee Tong; Rego, Eliane; Garrido, Bruno; Allegri, Gabriella; de La Cruz, Marcia; Barrabin, Juliana; Puglisi, Celia; Lopez, Eduardo; Lee, Hwashim; Kim, Byungjoo; Delatour, Vincent; Heuillet, Maud; Nammoonnoy, Jintana; Ceyhan Gören, Ahmet; Bilsel, Gokhan; Konopelko, L.; Krylov, A.; Lopushanskaya, E.

    2018-01-01

    Cholesterol is one of the most frequently measured substances in human blood/serum to assist in assessing the health status of individuals. Because of its clinical significance, CCQM-K6 determination of cholesterol in serum was completed in 2000 as one of the first key comparison (KC) studies performed within the Organic Analysis Working Group (OAWG). The first subsequent KC for cholesterol, CCQM-K6.1, was completed in 2001. Measurements for this second subsequent, CCQM-K6.2, were completed in 2012. These subsequent comparisons were conducted to enable CCQM members that had not participated in earlier studies to demonstrate their capabilities to measure a nonpolar (pKow mass (100 g/mol to 500 g/mol) metabolite in human serum at relatively high concentrations (1 mg/g to 3 mg/g) found in normal populations. Successful participation in CCQM-K6.2 demonstrated capabilities in analysis of complex biological matrices including sample preparation (extraction, derivatization), LC or GC separation, and quantification using an isotope dilution mass spectrometry approach. Normally in a subsequent KC, no key comparison reference value (KCRV) would be established and assessment of performance would be via the deviation of participants' results to the anchor institute's results, adjusted to account for the anchor's performance in the original comparison versus its KCRV. Due to the very long-time period since the original key comparison, the OAWG decided that this did not represent the best approach to assess performance in what is a relatively complex measurement. Given the excellent agreement between the anchor institute's results and robust consensus summary of the participants' values, the reference value for this study was taken as the anchor institute's result and treated as a 'KCRV'. Seven of the nine participants demonstrated agreement with the reference value. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears

  16. The establishment of a WHO Reference Reagent for anti-malaria (Plasmodium falciparum) human serum.

    Science.gov (United States)

    Bryan, Donna; Silva, Nilupa; Rigsby, Peter; Dougall, Thomas; Corran, Patrick; Bowyer, Paul W; Ho, Mei Mei

    2017-08-05

    At a World Health Organization (WHO) sponsored meeting it was concluded that there is an urgent need for a reference preparation that contains antibodies against malaria antigens in order to support serology studies and vaccine development. It was proposed that this reference would take the form of a lyophilized serum or plasma pool from a malaria-endemic area. In response, an immunoassay standard, comprising defibrinated human plasma has been prepared and evaluated in a collaborative study. A pool of human plasma from a malaria endemic region was collected from 140 single plasma donations selected for reactivity to Plasmodium falciparum apical membrane antigen-1 (AMA-1) and merozoite surface proteins (MSP-1 19 , MSP-1 42 , MSP-2 and MSP-3). This pool was defibrinated, filled and freeze dried into a single batch of ampoules to yield a stable source of naturally occurring antibodies to P. falciparum. The preparation was evaluated by an enzyme-linked immunosorbent assay (ELISA) in a collaborative study with sixteen participants from twelve different countries. This anti-malaria human serum preparation (NIBSC Code: 10/198) was adopted by the WHO Expert Committee on Biological Standardization (ECBS) in October 2014, as the first WHO reference reagent for anti-malaria (Plasmodium falciparum) human serum with an assigned arbitrary unitage of 100 units (U) per ampoule. Analysis of the reference reagent in a collaborative study has demonstrated the benefit of this preparation for the reduction in inter- and intra-laboratory variability in ELISA. Whilst locally sourced pools are regularly use for harmonization both within and between a few laboratories, the presence of a WHO-endorsed reference reagent should enable optimal harmonization of malaria serological assays either by direct use of the reference reagent or calibration of local standards against this WHO reference. The intended uses of this reference reagent, a multivalent preparation, are (1) to allow cross

  17. An effective colorimetric and ratiometric fluorescent probe for bisulfite in aqueous solution

    International Nuclear Information System (INIS)

    Dai, Xi; Zhang, Tao; Du, Zhi-Fang; Cao, Xiang-Jian; Chen, Ming-Yu; Hu, Sheng-Wen; Miao, Jun-Ying; Zhao, Bao-Xiang

    2015-01-01

    We have developed the first two-photon colorimetric and ratiometric fluorescent probe, BICO, for the detection of bisulfite (HSO 3 − ) in aqueous solution. The probe contains coumarin and benzimidazole moieties and can detect HSO 3 − based on the Michael addition reaction with a limit of detection 5.3 × 10 −8  M in phosphate-buffered saline solution. The probe was used to detect bisulfite in tap water, sugar and dry white wine. Moreover, test strips were made and used easily. We successfully applied the probe to image living cells, using one-photon fluorescence imaging. BICO overcomes the limitations in sensitivity of previously reported probes and the solvation effect of bisulfite, which demonstrates its excellent value in practical application. - Highlights: • A colorimetric and ratiometric fluorescent probe was developed. • The probe could detect bisulfite in PBS buffer solution and real samples. • Bisulfite test paper was made to naked-eye detect bisulfite. • This probe successfully used to living cell imaging in ratiometric manner

  18. An effective colorimetric and ratiometric fluorescent probe for bisulfite in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Xi [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zhang, Tao [Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Du, Zhi-Fang; Cao, Xiang-Jian; Chen, Ming-Yu [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Taishan College, Shandong University, Jinan 250100 (China); Hu, Sheng-Wen [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Miao, Jun-Ying, E-mail: miaojy@sdu.edu.cn [Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100 (China); Zhao, Bao-Xiang, E-mail: bxzhao@sdu.edu.cn [Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2015-08-12

    We have developed the first two-photon colorimetric and ratiometric fluorescent probe, BICO, for the detection of bisulfite (HSO{sub 3}{sup −}) in aqueous solution. The probe contains coumarin and benzimidazole moieties and can detect HSO{sub 3}{sup −} based on the Michael addition reaction with a limit of detection 5.3 × 10{sup −8} M in phosphate-buffered saline solution. The probe was used to detect bisulfite in tap water, sugar and dry white wine. Moreover, test strips were made and used easily. We successfully applied the probe to image living cells, using one-photon fluorescence imaging. BICO overcomes the limitations in sensitivity of previously reported probes and the solvation effect of bisulfite, which demonstrates its excellent value in practical application. - Highlights: • A colorimetric and ratiometric fluorescent probe was developed. • The probe could detect bisulfite in PBS buffer solution and real samples. • Bisulfite test paper was made to naked-eye detect bisulfite. • This probe successfully used to living cell imaging in ratiometric manner.

  19. Immunotoxicity assessment of rice-derived recombinant human serum albumin using human peripheral blood mononuclear cells.

    Directory of Open Access Journals (Sweden)

    Kai Fu

    Full Text Available Human serum albumin (HSA is extensively used in clinics to treat a variety of diseases, such as hypoproteinemia, hemorrhagic shock, serious burn injuries, cirrhotic ascites and fetal erythroblastosis. To address supply shortages and high safety risks from limited human donors, we recently developed recombinant technology to produce HSA from rice endosperm. To assess the risk potential of HSA derived from Oryza sativa (OsrHSA before a First-in-human (FIH trial, we compared OsrHSA and plasma-derived HSA (pHSA, evaluating the potential for an immune reaction and toxicity using human peripheral blood mononuclear cells (PBMCs. The results indicated that neither OsrHSA nor pHSA stimulated T cell proliferation at 1x and 5x dosages. We also found no significant differences in the profiles of the CD4(+ and CD8(+ T cell subsets between OsrHSA- and pHSA-treated cells. Furthermore, the results showed that there were no significant differences between OsrHSA and pHSA in the production of cytokines such as interferon-gamma (IFN-γ, tumor necrosis factor-alpha (TNF-α, interleukin (IL-10 and IL-4. Our results demonstrated that OsrHSA has equivalent immunotoxicity to pHSA when using the PBMC model. Moreover, this ex vivo system could provide an alternative approach to predict potential risks in novel biopharmaceutical development.

  20. Technetium-99m-Labeled Autologous Serum Albumin: A Personal-Exclusive Source of Serum Component

    OpenAIRE

    Wang, Yuh-Feng; Chen, Yi-Chun; Li, Dian-Kun; Chuang, Mei-Hua

    2011-01-01

    Technetium-99m human serum albumin (99mTc-HSA) is an important radiopharmaceutical required in nuclear medicine studies. However, the risk of transfusion-transmitted infection remains a major safety concern. Autopreparation of serum component acquired from patient provides a “personal-exclusive” source for radiolabeling. This paper is to evaluate the practicality of on-site elusion and subsequent radiolabeling efficacy for serum albumin. Results showed that the autologous elute contained more...

  1. Basic design principles of colorimetric vision systems

    Science.gov (United States)

    Mumzhiu, Alex M.

    1998-10-01

    Color measurement is an important part of overall production quality control in textile, coating, plastics, food, paper and other industries. The color measurement instruments such as colorimeters and spectrophotometers, used for production quality control have many limitations. In many applications they cannot be used for a variety of reasons and have to be replaced with human operators. Machine vision has great potential for color measurement. The components for color machine vision systems, such as broadcast quality 3-CCD cameras, fast and inexpensive PCI frame grabbers, and sophisticated image processing software packages are available. However the machine vision industry has only started to approach the color domain. The few color machine vision systems on the market, produced by the largest machine vision manufacturers have very limited capabilities. A lack of understanding that a vision based color measurement system could fail if it ignores the basic principles of colorimetry is the main reason for the slow progress of color vision systems. the purpose of this paper is to clarify how color measurement principles have to be applied to vision systems and how the electro-optical design features of colorimeters have to be modified in order to implement them for vision systems. The subject of this presentation far exceeds the limitations of a journal paper so only the most important aspects will be discussed. An overview of the major areas of applications for colorimetric vision system will be discussed. Finally, the reasons why some customers are happy with their vision systems and some are not will be analyzed.

  2. Colorimetric detection of riboflavin by silver nanoparticles capped with β-cyclodextrin-grafted citrate.

    Science.gov (United States)

    Ma, Qi; Song, Jinping; Zhang, Sufang; Wang, Meifang; Guo, Yong; Dong, Chuan

    2016-12-01

    β-Cyclodextrin-grafted citrate was used for the first time as a stabilizer and reducer to prepare silver nanoparticles (AgNPs). The as-synthesized AgNPs were further characterized by UV-vis absorption spectroscopy, powder X-ray diffraction spectroscopy, and transmission electron microscopy. The results show that the presence of riboflavin caused severe aggregation of the nanoparticles, thereby inducing a colour change from yellow to red. 1 H NMR further verified the formation of non-inclusion complexes between riboflavin and β-cyclodextrin-grafted citrate. Hydrogen bond was considered the main driving force of the interaction between the riboflavin and external rim of β-cyclodextrin. Based on these observations, the as-synthesized AgNPs were utilized to develop a novel colorimetric sensor for riboflavin detection. This colorimetric probe showed excellent selectivity and high sensitivity for riboflavin with a detection limit of 167nM. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Multi-colorimetric sensor array for detection of explosives in gas and liquid phase

    DEFF Research Database (Denmark)

    Kostesha, Natalie; Alstrøm, Tommy Sonne; Johnsen, C.

    2011-01-01

    In the framework of the research project "Xsense" at the Technical University of Denmark (DTU) we are developing a simple colorimetric sensor array which can be useful in detection of explosives like DNT, TATP, HMX, RDX and identification of reagents needed for making homemade explosives. The tec......In the framework of the research project "Xsense" at the Technical University of Denmark (DTU) we are developing a simple colorimetric sensor array which can be useful in detection of explosives like DNT, TATP, HMX, RDX and identification of reagents needed for making homemade explosives...... to the analytes creates a color difference map which gives a unique fingerprint for each explosive and VOCs. Such sensing technology can be used for screening relevant explosives in a complex background as well as to distinguish mixtures of volatile organic compounds distributed in gas and liquid phases....... This sensor array is inexpensive, and can potentially be produced as single use disposable....

  4. An imaging-based photometric and colorimetric measurement method for characterizing OLED panels for lighting applications

    Science.gov (United States)

    Zhu, Yiting; Narendran, Nadarajah; Tan, Jianchuan; Mou, Xi

    2014-09-01

    The organic light-emitting diode (OLED) has demonstrated its novelty in displays and certain lighting applications. Similar to white light-emitting diode (LED) technology, it also holds the promise of saving energy. Even though the luminous efficacy values of OLED products have been steadily growing, their longevity is still not well understood. Furthermore, currently there is no industry standard for photometric and colorimetric testing, short and long term, of OLEDs. Each OLED manufacturer tests its OLED panels under different electrical and thermal conditions using different measurement methods. In this study, an imaging-based photometric and colorimetric measurement method for OLED panels was investigated. Unlike an LED that can be considered as a point source, the OLED is a large form area source. Therefore, for an area source to satisfy lighting application needs, it is important that it maintains uniform light level and color properties across the emitting surface of the panel over a long period. This study intended to develop a measurement procedure that can be used to test long-term photometric and colorimetric properties of OLED panels. The objective was to better understand how test parameters such as drive current or luminance and temperature affect the degradation rate. In addition, this study investigated whether data interpolation could allow for determination of degradation and lifetime, L70, at application conditions based on the degradation rates measured at different operating conditions.

  5. Serum oxidized low density lipoprotein levels in preeclamptic and normotensive pregnants.

    Science.gov (United States)

    Kozan, A; Yildirmak, S Turkmen; Mihmanli, V; Ayabakan, H; Cicek, Y G; Kalaslioglu, V; Doean, S; Cebeci, H Cerci

    2015-01-01

    BACKGROUNDS/AIM: The aim of the study was to determine serum lipids and oxidized low density lipoprotein (ox-LDL) levels in preeclamptic pregnants and compare with those of normotensives. Ox-LDL levels were determined by enzyme linked immunosorbent assay (ELISA); total cholesterol, hight density lipoprotein (HDL)-cholesterol and triglyceride levels were measured by enzymatic colorimetric assay in 26 normotensive and 27 preeclamptic pregnants. LDL and very low density lipoprotein (VLDL) cholesterol was calculated by Friedwald formula. Serum levels of Ox-LDL (U/L), total-cholesterol (mg/dL), HDL-cholesterol (mg/dL), LDL-cholesterol (mg/dL), triglyceride (mg/dL), and VLDL-cholesterol (mg/dL) in normotensive and preeclamptic pregnants were found as 130±60 and 133±69; 248±49 and 248±81; 67±14 and 61±16; 147±61 and 135±59; 207±76 and 256±87; 41±15 and 50±17, respectively. Mean values of Ox-LDL and other lipid parameters were higher than the upper limits of their reference ranges in both of groups. However no significant differences were found in Ox-LDL, total, HDL and LDL-cholesterol levels between two groups. However, the levels of triglyceride and VLDL-cholesterol were significantly higher in preeclampsia group. The present results suggest that the levels of serum Ox-LDL and other lipid parameters rise as a result of pregnancy rather than as a result of preeclampsia.

  6. Commercial radioimmunoassay for beta subunit of human chorionic gonadotropin: falsely positive determinations due to elevated serum luteinizing hormone

    International Nuclear Information System (INIS)

    Fowler, J.E. Jr.; Platoff, G.E.; Kubrock, C.A.; Stuzman, R.E.

    1982-01-01

    Among 17 men who had received seemingly curative treatment for unilateral non-seminomatous germ cell tumors for the testis and who had consistently normal serum human chorionic gonadotropin (HCG) levels at a reference laboratory, 7 (41%) had at least one falsely positive commercial serum HCG determination. To investigate the cause of these falsely positive determinations the authors measured the cross reactivity of luteinizing hormone (LH) and follicle stimulating hormone (FSH) standards in the commercial HCG assay, and studied the relationships between commercial HCG levels and serum LH levels, serum FSH levels and gonadal status in men with and without normal gonadal function. The falsely positive HCG determinations appeared to be due to elevated serum LH levels and cross reactivity of LH in the commercial HCG assay because: 1) there was substantial cross reactivity of the LH standards in the commercial assay, 2) the serum LH was elevated in four of six men with solitary testes, 3) there was a striking correlation between elevated serum LH levels and falsely elevated commercial HCG levels in ten men with solitary or absent testes, and 4) there were no falsely positive HCG determinations in 13 normal men but there were falsely positive HCG determinations in seven of ten anorchid men

  7. A novel colorimetric method based on copper nanoclusters with intrinsic peroxidase-like for detecting xanthine in serum samples

    Science.gov (United States)

    Yan, Zhengyu; Niu, Qianqian; Mou, Mingyao; Wu, Yi; Liu, Xiaoxuan; Liao, Shenghua

    2017-07-01

    A facile strategy for detecting xanthine in serum samples by copper nanocluster (CuNCs) with high intrinsic peroxidase-like activity was reported. Firstly, a simple, mild and time-saving method for preparing CuNCs was developed, in which dithiothreitol (DTT) and bovine serum albumin (BSA) were used as reductant and stabilizer, respectively. The as-prepared CuNCs exhibited a fluorescence emission at 590 nm with a quantum yield (QY) of approximately 5.29%, the fluorescence intensity of the as-prepared CuNCs exhibited no considerable change when stored under ambient condition with the lifetime is 1.75 μs. Moreover, the as-prepared CuNCs exhibited high intrinsic peroxidase-like activity with lower K m ( K m = 8.90 × 10-6 mol L-1) for H2O2, which indicated that CuNCs have a higher affinity for H2O2. Compared with natural enzyme, the as-synthesized CuNCs are more catalytic stable over a wide range of pH (4.0 13.0) and temperature (4 80 °C). Finally, an indirect method for sensing xanthine was established because xanthine oxidase can catalyse the oxidation of xanthine to produce H2O2. Xanthine could be detected as low as 3.8 × 10-7 mol L-1 with a linear range from 5.0 × 10-7 to 1.0 × 10-4 mol L-1. These results proved that the proposed method is sensitive and accurate and could be successfully applied to the determination of xanthine in the serum sample with satisfaction.

  8. Palladium nanoparticles in electrochemical sensing of trace terazosin in human serum and pharmaceutical preparations

    Energy Technology Data Exchange (ETDEWEB)

    Sefid-sefidehkhan, Yasaman [Department of Chemistry, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of); Nekoueian, Khadijeh [Laboratory of Green Chemistry, Faculty of Technology, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Amiri, Mandana, E-mail: mandanaamiri@uma.ac.ir [Department of Chemistry, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of); Sillanpaa, Mika [Laboratory of Green Chemistry, Faculty of Technology, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Eskandari, Habibollah [Department of Chemistry, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of)

    2017-06-01

    In this approach, palladium nanoparticle film was simply fabricated on the surface of carbon paste electrode by electrochemical deposition method. The film was characterized using scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The prepared electrode exhibited an excellent electrocatalytic activity toward detection of trace amounts of terazosin, which is an antihypertensive drug. Under the optimum experimental conditions, a linear range of 1.0 × 10{sup −8}–1.0 × 10{sup −3} mol L{sup −1} with a detection limit of 1.9 × 10{sup −9} mol L{sup −1} was obtained for determination of terazosin using differential pulse voltammetry as a sensitive method. The efficiency of palladium nanoparticle film on the surface of carbon paste electrode successfully proved for determination of terazosin in pharmaceutical sample and human serum sample with promising recovery results. The effect of some foreign species has been studied. - Highlights: • PdNPs were simply fabricated by electrochemical deposition. • PdNPs exhibited an excellent electrocatalytic activity toward oxidation of terazosin. • Terazosin has been determined in pharmaceutical sample and human serum sample.

  9. Serum Metabolomics Investigation of Humanized Mouse Model of Dengue Virus Infection.

    Science.gov (United States)

    Cui, Liang; Hou, Jue; Fang, Jinling; Lee, Yie Hou; Costa, Vivian Vasconcelos; Wong, Lan Hiong; Chen, Qingfeng; Ooi, Eng Eong; Tannenbaum, Steven R; Chen, Jianzhu; Ong, Choon Nam

    2017-07-15

    Dengue is an acute febrile illness caused by dengue virus (DENV) and a major cause of morbidity and mortality in tropical and subtropical regions of the world. The lack of an appropriate small-animal model of dengue infection has greatly hindered the study of dengue pathogenesis and the development of therapeutics. In this study, we conducted mass spectrometry-based serum metabolic profiling from a model using humanized mice (humice) with DENV serotype 2 infection at 0, 3, 7, 14, and 28 days postinfection (dpi). Forty-eight differential metabolites were identified, including fatty acids, purines and pyrimidines, acylcarnitines, acylglycines, phospholipids, sphingolipids, amino acids and derivatives, free fatty acids, and bile acid. These metabolites showed a reversible-change trend-most were significantly perturbed at 3 or 7 dpi and returned to control levels at 14 or 28 dpi, indicating that the metabolites might serve as prognostic markers of the disease in humice. The major perturbed metabolic pathways included purine and pyrimidine metabolism, fatty acid β-oxidation, phospholipid catabolism, arachidonic acid and linoleic acid metabolism, sphingolipid metabolism, tryptophan metabolism, phenylalanine metabolism, lysine biosynthesis and degradation, and bile acid biosynthesis. Most of these disturbed pathways are similar to our previous metabolomics findings in a longitudinal cohort of adult human dengue patients across different infection stages. Our analyses revealed the commonalities of host responses to DENV infection between humice and humans and suggested that humice could be a useful small-animal model for the study of dengue pathogenesis and the development of dengue therapeutics. IMPORTANCE Dengue virus is the most widespread arbovirus, causing an estimated 390 million dengue infections worldwide every year. There is currently no effective treatment for the disease, and the lack of an appropriate small-animal model of dengue infection has greatly

  10. Levels of non-ortho- and mono-ortho-substituted polychlorinated biphenyls in human serum near to waste incinerator from Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.S.; Jong-Guk, K. [Dept. of Environmental Engineering, Chonbuk National Univ., Jeonju (Korea); Yeon-Je, K. [Doping Control Center, Korea Inst. of Science and Technology, Seoul (Korea)

    2004-09-15

    Dioxins and PCBs are the most important persistent organic compounds found in the environment, which are toxic to human and other living organisms. Now a days, environmental contamination by dioxin is mainly from the waste incinerator emissions and also from other sources. Hence, the control and monitoring of dioxins are having much important role in developed countries when the environmental management is concerned. These chemicals are ubiquitous in the environment and, therefore, it can be also found in adipose tissues, human milk, blood plasma, and serum of the human. The previous reports from USA and Europe showed that the milk and beef were of good indicators for the evaluation of the environmental impacts due to incinerators. In Japan, the shellfishes and fishes contaminated with PCDDs contribute significant amount to human. Though there are many studies related to human exposure, toxicity and health effects due to PCDD/Fs, there are only few reports available in Korea. In this study, we provide specific-congener data of Co-PCBs in serum of the residents living near to the waste incinerator.

  11. Magnetic relaxation switch and colorimetric detection of thrombin using aptamer-functionalized gold-coated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Liang Guohai; Cai Shaoyu; Zhang Peng [Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433 (China); Peng Youyuan [Department of Chemistry, Quanzhou Normal University, Quanzhou 362000 (China); Chen Hui; Zhang Song [Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433 (China); Kong Jilie, E-mail: jlkong@fudan.edu.cn [Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433 (China)

    2011-03-18

    We describe a sensitive biosensing system combining magnetic relaxation switch diagnosis and colorimetric detection of human {alpha}-thrombin, based on the aptamer-protein interaction induced aggregation of Fe{sub 3}O{sub 4}-Au nanoparticles. To demonstrate the concept, gold-coated iron oxide nanoparticle was synthesized by iterative reduction of HAuCl{sub 4} onto the dextran-coated Fe{sub 3}O{sub 4} nanoparticles. The resulting core-shell structure had a flowerlike shape with pretty narrow size distribution (referred to as 'nanorose'). The two aptamers corresponding to human {alpha}-thrombin were conjugated separately to two distinct nanorose populations. Once a solution containing human {alpha}-thrombin was introduced, the nanoroses switched from a well dispersed state to an aggregated one, leading to a change in the spin-spin relaxation time (T{sub 2}) as well as the UV-Vis absorption spectra of the solution. Thus the qualitative and quantitative detection method for human {alpha}-thrombin was established. The dual-mode detection is clearly advantageous in obtaining a more reliable result; the detection range is widened as well. By using the dual-mode detection method, a detectable T{sub 2} change is observed with 1.0 nM human {alpha}-thrombin, and the detection range is from 1.6 nM to 30.4 nM.

  12. Analysis of human serum by liquid chromatography-mass spectrometry: improved sample preparation and data analysis.

    Science.gov (United States)

    Govorukhina, N I; Reijmers, T H; Nyangoma, S O; van der Zee, A G J; Jansen, R C; Bischoff, R

    2006-07-07

    Discovery of biomarkers is a fast developing field in proteomics research. Liquid chromatography coupled on line to mass spectrometry (LC-MS) has become a powerful method for the sensitive detection, quantification and identification of proteins and peptides in biological fluids like serum. However, the presence of highly abundant proteins often masks those of lower abundance and thus generally prevents their detection and identification in proteomics studies. To perform future comparative analyses of samples from a serum bank of cervical cancer patients in a longitudinal and cross-sectional manner, methodology based on the depletion of high-abundance proteins followed by tryptic digestion and LC-MS has been developed. Two sample preparation methods were tested in terms of their efficiency to deplete high-abundance serum proteins and how they affect the repeatability of the LC-MS data sets. The first method comprised depletion of human serum albumin (HSA) on a dye ligand chromatographic and immunoglobulin G (IgG) on an immobilized Protein A support followed by tryptic digestion, fractionation by cation-exchange chromatography, trapping on a C18 column and reversed-phase LC-MS. The second method included depletion of the six most abundant serum proteins based on multiple immunoaffinity chromatography followed by tryptic digestion, trapping on a C18 column and reversed-phase LC-MS. Repeatability of the overall procedures was evaluated in terms of retention time and peak area for a selected number of endogenous peptides showing that the second method, besides being less time consuming, gave more repeatable results (retention time: <0.1% RSD; peak area: <30% RSD). Application of an LC-MS component detection algorithm followed by principal component analysis (PCA) enabled discrimination of serum samples that were spiked with horse heart cytochrome C from non-spiked serum and the detection of a concentration trend, which correlated to the amount of spiked horse heart

  13. Human serum albumin binding of certain antimalarials

    Science.gov (United States)

    Marković, Olivera S.; Cvijetić, Ilija N.; Zlatović, Mario V.; Opsenica, Igor M.; Konstantinović, Jelena M.; Terzić Jovanović, Nataša V.; Šolaja, Bogdan A.; Verbić, Tatjana Ž.

    2018-03-01

    Interactions between eight in-house synthesized aminoquinolines, along with well-known chloroquine, and human serum albumin (HSA) have been studied by fluorescence spectroscopy. The synthesized aminoquinolines, despite being structurally diverse, were found to be very potent antimalarials. Fluorescence measurements indicate that three compounds having additional thiophene or benzothiophene substructure bind more strongly to HSA than other studied compounds. Competitive binding experiments indicate that these three compounds bind significantly stronger to warfarin compared to diazepam binding site. Fluorescence quenching at three temperatures (20, 25, and 37 °C) was analyzed using classical Stern-Volmer equation, and a static quenching mechanism was proposed. The enthalpy and entropy changes upon sulphur-containing compound-HSA interactions were calculated using Van't Hoff equation. Positive values of enthalpy and entropy changes indicate that non-specific, hydrophobic interactions are the main contributors to HSA-compound interaction. Molecular docking and calculated lipophilicity descriptors indicate the same, pointing out that the increased lipophilicity of sulphur-containing compounds might be a reason for their better binding to HSA. Obtained results might contribute to design of novel derivatives with improved pharmacokinetic properties and drug efficacy.

  14. Fluorescent and Colorimetric Molecular Recognition Probe for Hydrogen Bond Acceptors

    OpenAIRE

    Pike, Sarah Jane; Hunter, Christopher Alexander

    2018-01-01

    The association constants for formation of 1 : 1 complexes between a H-bond donor, 1-naphthol, and a diverse range of charged and neutral H-bond acceptors have been measured using UV/vis absorption and fluorescence emission titrations. The performance of 1-naphthol as a dual colorimetric and fluorescent molecular recognition probe for determining the H-bond acceptor (HBA) parameters of charged and neutral solutes has been investigated in three solvents. The data were employed to establish sel...

  15. Purification of PON1 from human serum and assessment of enzyme kinetics against metal toxicity.

    Science.gov (United States)

    Ekinci, Deniz; Beydemir, Sükrü

    2010-06-01

    Paraoxonase-1 (PON1) is an organophosphate hydrolyser enzyme which has also antioxidant properties in metabolism. Due to its crucial functions, inhibition of the enzyme is undesirable and very dangerous. PON1 enzyme activity should not be altered in any case. Inhibitory investigations of this enzyme are therefore important and useful. Metal toxicology of enzymes has become popular in the recent years. Here, we report the in vitro inhibitory effects of some metal ions, including Pb(+2), Cr(+2), Fe(+2), and Zn(+2), on the activity of human serum PON1 (hPON1; EC 3.1.8.1.). For this purpose, we purified the enzyme from human serum and analyzed the alterations in the enzyme activity in the presence of metal ions. The results show that metal ions exhibit inhibitory effects on hPON1 at low concentrations with IC (50) values ranging from 0.838 to 7.410 mM. Metal ions showed different inhibition mechanisms: lead and iron were competitive, chrome was noncompetitive, and zinc was uncompetitive. Lead was determined to be the most effective inhibitor.

  16. A colorimetric sensor array for identification of toxic gases below permissible exposure limits†

    OpenAIRE

    Feng, Liang; Musto, Christopher J.; Kemling, Jonathan W.; Lim, Sung H.; Suslick, Kenneth S.

    2010-01-01

    A colorimetric sensor array has been developed for the rapid and sensitive detection of 20 toxic industrial chemicals (TICs) at their PELs (permissible exposure limits). The color changes in an array of chemically responsive nanoporous pigments provide facile identification of the TICs with an error rate below 0.7%.

  17. A note on the electrolytic preparation of sup(99m)Tc human serum albumin

    International Nuclear Information System (INIS)

    Ligny, C.L. de; Dekker, B.G.

    1978-01-01

    A note to the simple electrolytic preparations of Tc-99m human serum albumin using tin electrodes, elaborated by Narasimhan and Mani, is described. Narasimhan and Mani's procedure yields mainly hydrolysed reduced Tc. Gil et al described a modification of Narasimhan and Mani's procedure wherein about 60% Tc-HSA chelate can be obtained. Purity analysis was performed by paper chromatography with 85% methanol as eluent. (T.I.)

  18. STUDY OF SERUM HAPTOGLOBIN LEVEL AND ITS RELATION TO ERYTHROPOIETIC ACTIVITY IN BETA THALASSEMIA CHILDREN .

    Directory of Open Access Journals (Sweden)

    Seham Ragab

    2015-02-01

    Full Text Available Background  :Serum haptoglobin (Hp is a reliable marker for hemolysis regardless the inflammatory state.  Objective: We investigated the possible relation between Hp depletion and hemolysis severity, hepatitis C virus (HCV infection and iron load in β-thalassemia children. Methods: Twenty  two β-thalassemia major (TM ,20 β-thalassemia  intermedia (TI children with 20 age and sex matched healthy controls were involved. Pre-transfusion hemoglobin level was considered . Serum ferritin , Hp  and transferrin receptor  levels (sTfR  (by ELISA , alanine aminotransferase (ALT and  aspartate aminotransferase (AST  (by colorimetric method were assayed. Markers of hepatitis C virus  (HCV  were done by PCR. Results:  The mean Hp levels among the studied groups were as follows; 8.02 ± 0.93 (mg/dl , 8.6 ±0.72 (mg/dl  and 122  ± 18.5(mg/dl   for TM ,TI and the controls respectively . Both patient groups had significantly lower Hp level compared to the controls (P<0.0001  with significant lower level in TM compared to TI  children ( P= 0.034  .Significant inverse correlations were  found between serum Hp and sTfR levels in thalassemia children combined and in each group (TM and TI as well as among HCV infected children. STfR   was the only significant independent predictor for  serum Hp level (t= -5.585 , P<0.0001 . Among  HCV infected patients , no significant correlation was found between serum Hp and serum transaminases  .Conclusion:  Serum Hp depletion in thalassemia had significant relation to disease severity and correlated   well with their erythropoietic activity, as assessed by the measurement of  sTfR without significant relation  HCV infection . Large sample  multicenter studies are  recommended.

  19. Biophysical studies of interaction between hydrolysable tannins isolated from Oenothera gigas and Geranium sanguineum with human serum albumin.

    Science.gov (United States)

    Sekowski, Szymon; Ionov, Maksim; Kaszuba, Mateusz; Mavlyanov, Saidmukhtar; Bryszewska, Maria; Zamaraeva, Maria

    2014-11-01

    Tannins, secondary plant metabolites, possess diverse biological activities and can interact with biopolymers such as lipids or proteins. Interactions between tannins and proteins depend on the structures of both and can result in changes in protein structure and activity. Because human serum albumin is the most abundant protein in plasma and responsible for interactions with important biological compounds (e.g. bilirubin) and proper blood pressure, therefore, it is very important to investigate reactions between HSA and tannins. This paper describes the interaction between human serum albumin (HSA) and two tannins: bihexahydroxydiphenoyl-trigalloylglucose (BDTG) and 1-O-galloyl-4,6-hexahydroxydiphenoyl-β-d-glucose (OGβDG), isolated from Geranium sanguineum and Oenothera gigas leafs, respectively. Optical (spectrofluorimetric) and chiral optical (circular dichroism) methods were used in this study. Fluorescence analysis demonstrated that OGβDG quenched HSA fluorescence more strongly than BDTG. Both OGβDG and BDTG formed complexes with albumin and caused a red shift of the fluorescence spectra but did not significantly change the protein secondary structure. Our studies clearly demonstrate that the tested tannins interact very strongly with human serum albumin (quenching constant K=88,277.26±407.04 M(-1) and K=55,552.67±583.07 M(-1) respectively for OGβDG and BDTG) in a manner depending on their chemical structure. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Urinary estrogen excretion and concentration of serum human placental lactogen in pregnancies following legally induced abortion

    DEFF Research Database (Denmark)

    Obel, E B; Madsen, Mette

    1980-01-01

    Feto-placental function was assessed by 24-hour excretion of estrogen in urine and by the concentration of human Placental Lactogen (hPL) in serum in pregnant women whose previous pregnancy was terminated by legally induced abortion. The mean 24-hour excretion of estrogens in urine and the mean...... an increased frequency of dysfunction of the feto-placental unit during the last part of pregnancy in women with previous legally induced abortion. These findings indicate that legal abortion does not seem to increase the frequency of retarded intrauterine growth in a subsequent pregnancy....... concentration of hPL in serum were no lower in this group than in women without previous induced abortion. Neither was the frequency of a low 24-hour excretion of estrogens in urine or low concentration of hPL in serum (values less than mean - 1.96 s) found to be increased. This study could not demonstrate...

  1. Thin films of single-walled carbon nanotubes promote human osteoblastic cells (Saos-2) proliferation in low serum concentrations

    International Nuclear Information System (INIS)

    Akasaka, Tsukasa; Yokoyama, Atsuro; Matsuoka, Makoto; Hashimoto, Takeshi; Watari, Fumio

    2010-01-01

    One strategy used for the regeneration of bone is the development of cell culture substrates and scaffolds that can control osteoblast proliferation and differentiation. In recent investigations, carbon nanotubes (CNTs) have been utilized as scaffolds for osteoblastic cell cultures; however, there are only a few reports describing the proliferation of osteoblastic cells on thin CNT films; in particular, the effects of serum concentration on cell proliferation have not been studied. In the present study, we prepared culture dishes with homogeneous thin or thick films of non-modified CNTs and examined the effect of serum concentrations on human osteoblastic cells (Saos-2) proliferation in these culture dishes. We demonstrated that the ratio of cell proliferation was strongly affected by the concentration of serum. Interestingly, single-walled carbon nanotube (SWNT) thin films were found to be the most effective substrate for the proliferation of Saos-2 cells in low concentrations of serum. Thus, thin SWNT films may be used as an effective biomaterial for the culture of Saos-2 cells in low serum concentrations.

  2. Is DTPA a good competing chelating agent for Th(IV) in human serum and suitable in targeted alpha therapy?

    Science.gov (United States)

    Le Du, Alicia; Sabatié-Gogova, Andrea; Morgenstern, Alfred; Montavon, Gilles

    2012-04-01

    The interaction between thorium and human serum components was studied using difference ultraviolet spectroscopy (DUS), ultrafiltration and high-pressure-anion exchange chromatography (HPAEC) with external inductively conducted plasma mass spectrometry (ICP-MS) analysis. Experimental data are compared with modelling results based on the law of mass action. Human serum transferrin (HSTF) interacts strongly with Th(IV), forming a ternary complex including two synergistic carbonate anions. This complex governs Th(IV) speciation under blood serum conditions. Considering the generally used Langmuir-type model, values of 10(33.5) and 10(32.5) were obtained for strong and weak sites, respectively. We showed that trace amounts of diethylene triamine pentaacetic acid (DTPA) cannot complex Th(IV) in the blood serum at equilibrium. Unexpectedly this effect is not related to the competition with HSTF but is due to the strong competition with major divalent metal ions for DTPA. However, Th-DTPA complex was shown to be stable for a few hours when it is formed before addition in the biological medium; this is related to the high kinetic stability of the complex. This makes DTPA a potential chelating agent for synthesis of (226)Th-labelled biomolecules for application in targeted alpha therapy. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. On the variability of the salting-out curves of proteins of normal human plasma and serum

    NARCIS (Netherlands)

    Steyn-Parvé, Elizabeth P.; Hout, A.J. van den

    1953-01-01

    Salting-out curves of proteins of normal human plasma reflect the influence of a number of other factors besides the protein composition: the manner of obtaining the blood, the nature of the anti-coagulant used, the non-protein components of the plasma. Diagrams of serum and plasma obtained from

  4. Colorimetric microwell plate reverse-hybridization assay for Mycobacterium tuberculosis detection

    Directory of Open Access Journals (Sweden)

    Candice Tosi Michelon

    2011-03-01

    Full Text Available Direct smear examination using Ziehl-Neelsen staining for pulmonary tuberculosis (PTB diagnosis is inexpensive and easy to use, but has the major limitation of low sensitivity. Rapid molecular methods are becoming more widely available in centralized laboratories, but they depend on timely reporting of results and strict quality assurance obtainable only from costly commercial kits available in high burden nations. This study describes a pre-commercial colorimetric method, Detect-TB, for detecting Mycobacterium tuberculosis DNA in which an oligonucleotide probe is fixed onto wells of microwell plates and hybridized with biotinylated polymerase chain reaction amplification products derived from clinical samples. The probe is capable of hybridising with the IS6110 insertion element and was used to specifically recognise the M. tuberculosis complex. When combined with an improved silica-based DNA extraction method, the sensitivity of the test was 50 colony-forming units of the M. tuberculosis reference strain H37Rv. The results that were in agreement with reference detection methods were observed in 95.2% (453/476 of samples included in the analysis. Sensitivity and specificity for 301 induced sputum samples and 175 spontaneous sputum samples were 85% and 98%, and 94% and 100%, respectively. This colorimetric method showed similar specificity to that described for commercially available kits and may provide an important contribution for PTB diagnosis.

  5. Human Umbilical Cord Blood Serum Has Higher Potential in Inducing Proliferation of Fibroblast than Fetal Bovine Serum

    Directory of Open Access Journals (Sweden)

    Ferry Sandra

    2017-09-01

    Full Text Available Background: Cytokines and growth factors were reported to play an important role in stimulating fibroblast proliferation. In vitro culture, fibroblast is mostly culture in medium containing fetal bovine serum (FBS.  Human umbilical cord blood (hUCB has been reported to have low immunogenic property and potential in wound healing, so therefore hUCB serum (hUCBS could be potential and were investigated in current study. Materials and Methods: Five hUCBs were collected from healthy volunteers with normal delivering procedure. hUCB was ex utero immediately collected from umbilical vein in vacutainers and processed. NIH3T3 cells were cultured in DMEM with 10% FBS or 5-20% hUCBS for 48 hours. Cells were then quantified using MTT assay. Protein concentration of FBS and hUCBS were quantified using Bradford assay. Results: NIH3T3 cells density grown in DMEM with 10% FBS was the lowest. NIH3T3 cells densities were increased along with the increment of hUCBS concentrations. MTT results showed that average number of NIH3T3 cells grown in DMEM with 10% FBS was 6,185±1,243. Meanwhile average numbers of NIH3T3 cells grown in DMEM with 5%, 10% and 20% hUCBS were 8,126±628, 9,685±313 and 12,200±304, respectively. Average numbers of NIH3T3 cells grown in DMEM with 5% hUCBS were significantly higher than the ones with 10% FBS (p=0.000. Bradford results showed that concentration of hUCBS was significantly higher than the one of FBS (p=0.000. Conclusion: hUCBS could induce higher proliferation rate of NIH3T3 cells than FBS. Hence hUCBS could be suggested as an alternate of FBS in inducing fibroblast. Keywords: NIH3T3, fibroblast, UCB, serum, FBS, proliferation

  6. Assessment of the colorimetric and fluorometric assays for alkaline phosphatase activity in cow's, goat's, and sheep's milk.

    Science.gov (United States)

    Klotz, V; Hill, Art; Warriner, K; Griffiths, M; Odumeru, J

    2008-09-01

    Raw milk is a well-established vehicle for the carriage of human pathogens, and many regulatory bodies have consequently mandated compulsory pasteurization as a food safety intervention. The residual activity of alkaline phosphatase (ALP) has historically been used to verify the adequacy of pasteurization of cow's milk. However, there is uncertainty on how the current ALP standards and methods of analysis can be applied to sheep's and goat's milk, which naturally contain different levels of the enzyme than that found in cow's milk. The official ALP methods applied in Canada (colorimetric assay; MFO-3) and in the United States (Fluorophos) were assessed for their ability to detect enzyme activity in raw and pasteurized milk derived from cows, sheep, and goats. The detection limit and the limit of quantitation were 0.8 and 2.02 microg/ml phenol, respectively, for the MFO-3 method and 43 and 85 mU/liter, respectively, for the Fluorophos method. The average ALP levels in raw goat's, cow's, and sheep's milk were 165, 1,562, and 3,512 microg/ml phenol, respectively. Raw milk detection limits, which correspond to raw milk phosphatase levels, were 0.051, 0.485, and 0.023% in cow's, goat's, and sheep's milk, respectively, for the MFO-3 method and 0.007, 0.070, and 0.004%, respectively, for the Fluorophos method. Although both methods can be used for ALP determination in cow's, goat's, and sheep's milk, the Fluorophos assay was superior to the colorimetric MFO-3 method based on sensitivity and time required to complete the analysis.

  7. Activation of the human complement system by cholesterol-rich and pegylated liposomes - Modulation of cholesterol-rich liposome-mediated complement activation by elevated serum LDL and HDL levels

    DEFF Research Database (Denmark)

    Moghimi, S.M.; Hamad, I.; Bunger, R.

    2006-01-01

    level of S-protein-bound form of the terminal complex (SC5b-9). However, liposome-induced rise of SC5b-9 was significantly suppressed when serum HDL cholesterol levels increased by 30%. Increase of serum LDL to levels similar to that observed in heterozygous familial hypercholesterolemia also suppressed......Intravenously infused liposomes may induce cardiopulmonary distress in some human subjects, which is a manifestation of "complement activation-related pseudoallergy." We have now examined liposome-mediated complement activation in human sera with elevated lipoprotein (LDL and HDL) levels, since...... abnormal or racial differences in serum lipid profiles seem to modulate the extent of complement activation and associated adverse responses. In accordance with our earlier observations, cholesterol-rich (45 mol% cholesterol) liposomes activated human complement, as reflected by a significant rise in serum...

  8. Facile LC-UV methods for simultaneous monitoring of ciprofloxacin and rosuvastatin in API, formulations and human serum.

    Science.gov (United States)

    Arayne, M Saeed; Sultana, Najma; Tabassum, Arman

    2015-02-01

    An efficient, selective and cost-effective liquid chromatographic assay was developed and validated for the simultaneous quantification of ciprofloxacin and rosuvastatin in Active Pharmaceutical Ingredients (API), pharmaceutical formulations and in human serum. The chromatographic system consisted of mobile phase methanol-water, 90:10 v/v at pH 3.0 adjusted with o-phosphoric acid, pumped at 1.0 mL/min through a prepacked Purospher Star C18 (5 µm, 25 × 0.46 cm) column and effluent was monitored at the isosbestic point (255 nm) as well as at the λmax of individual drugs (243 and 271 nm). The method was validated over a linear concentration range of 0.25-15 µg/mL for ciprofloxacin and 0.33-20 µg/mL for rosuvastatin (r(2)  ≥ 0.999). The ranges of reliable response (limits of detection and quantitation) for ciprofloxacin were 3-15 and 9-45 ng/mL and 17-29 and 52-88 ng/mL, respectively, for rosuvastatin in all API, pharmaceutical formulations and human serum. Analytical recovery from human serum was >98% and relative standard deviation (RSD) was <2. The accuracies were 97.13-102.55 and 97.41-101.31% and precisions in RSD were 0.04-1.90 and 0.02-1.23% for ciprofloxacin and rosuvastatin, respectively. No matrix interferences, ion suppression/enhancement and carry-over were detected. The total assay run time was less than 5 min. In another study, for optimum performance the detector was programmed for multiwavelength scanning at the absorption maxima of each component. Consequently, the linearity range was improved and limit of detection and quantitation values were down to 1-4 and 4-12 ng/mL for ciprofloxacin and 3-5 and 9-15 ng/mL for rosuvastatin, respectively. The validation parameters fitted ICH guidelines through the isosbestic and individual λmax approach. The small sample volume and simplicity of preparation make this method suitable for use in human serum samples, pharmaceutical formulations, quality control, drug

  9. Towards A Colorimetric Digital Image Archive For The Visual Arts

    Science.gov (United States)

    Martinez, Kirk; Hamber, Anthony

    1989-04-01

    The aim of this project is to produce a high-resolution, colorimetric and permanent digital archive of images taken directly from works of art. The proposed system is designed for use in education, research, galleries and museums. Tentative user requirements are examined with particular reference to resolution, image access and colorimetry. Existing technology and projects are considered. Some 3000x3000 pel images of paintings are used to illustrate the interrelationship between dimensions of the original, its inherent detail, scan resolution and display.

  10. Serum Cytokine Responses over the Entire Clinical-Immunological Spectrum of Human Leishmania (L. infantum chagasi Infection

    Directory of Open Access Journals (Sweden)

    Patrícia Karla Ramos

    2016-01-01

    Full Text Available The clinical-immunological spectrum of human Leishmania (L. infantum chagasi infection in Amazonian Brazil was recently reviewed based on clinical, DTH, and IFAT (IgG evaluations that identified five profiles: three asymptomatic (asymptomatic infection, AI; subclinical resistant infection, SRI; and indeterminate initial infection, III and two symptomatic (symptomatic infection, SI; American visceral leishmaniasis, AVL; and subclinical oligosymptomatic infection, SOI. TNF-α, IL-4, IL-6, and IL-10 serum cytokines were analyzed using multiplexed Cytometric Bead Array in 161 samples from endemic areas in the Brazilian Amazon: SI [AVL] (21 cases, III (49, SRI (19, SOI (12, AI (36, and a control group [CG] (24. The highest IL-6 serum levels were observed in the SI profile (AVL; higher IL-10 serum levels were observed in SI than in SOI or CG and in AI and III than in SOI; higher TNF-α serum levels were seen in SI than in CG. Positive correlations were found between IL-6 and IL-10 serum levels in the SI and III profiles and between IL-6 and TNF-α and between IL-4 and TNF-α in the III profile. These results provide strong evidence for associating IL-6 and IL-10 with the immunopathogenesis of AVL and help clarify the role of these cytokines in the infection spectrum.

  11. Aggregation of Individual Sensing Units for Signal Accumulation: Conversion of Liquid-Phase Colorimetric Assay into Enhanced Surface-Tethered Electrochemical Analysis.

    Science.gov (United States)

    Wei, Tianxiang; Dong, Tingting; Wang, Zhaoyin; Bao, Jianchun; Tu, Wenwen; Dai, Zhihui

    2015-07-22

    A novel concept is proposed for converting liquid-phase colorimetric assay into enhanced surface-tethered electrochemical analysis, which is based on the analyte-induced formation of a network architecture of metal nanoparticles (MNs). In a proof-of-concept trial, thymine-functionalized silver nanoparticle (Ag-T) is designed as the sensing unit for Hg(2+) determination. Through a specific T-Hg(2+)-T coordination, the validation system based on functionalized sensing units not only can perform well in a colorimetric Hg(2+) assay, but also can be developed into a more sensitive and stable electrochemical Hg(2+) sensor. In electrochemical analysis, the simple principle of analyte-induced aggregation of MNs can be used as a dual signal amplification strategy for significantly improving the detection sensitivity. More importantly, those numerous and diverse colorimetric assays that rely on the target-induced aggregation of MNs can be augmented to satisfy the ambitious demands of sensitive analysis by converting them into electrochemical assays via this approach.

  12. Association of thyroid function with human serum ghrelin and leptin levels

    International Nuclear Information System (INIS)

    Wang Jinping; Xu Hao; Wu Qiulian

    2008-01-01

    Objective: To investigate the effect of different status of thyroid function (hypothyroidism and hyperthyroidism as well as euthyroid status) on serum ghrelin and leptin levels. Methods: The levels of serum ghrelin and leptin were determined by radio immunoassay in 46 untreated subjects with hyperthyroidism, 15 hyperthyroid patients achieved a euthyroid status after radioiodine 131 I therapy, 21 cases of hypothyroidism and 18 cases of normal controls, respectively. Meanwhile, the serum levels of free triiodothyronine (FT 3 ), free thyroxine (FT 4 ) and thyroid-stimulating hormone (TSH) were measured by chemiluminescence immune assay. Results: (1) The levels of serum ghrelin in untreated hyperthyroidism were significantly lower than those in hyperthyroid patients achieved a euthyroid status (t=3.21, P 3 (r=-0.29, P 4 (r=-0.26, P< 0.05), positively correlated with serum TSH (r=0.36, P<0.05); serum leptin levels did not correlate with thyroid hormone. Conclusion: The levels of serum ghrelin were differently under different thyroid functional status and correlated with thyroid hormone, while serum leptin were not. (authors)

  13. Simple colorimetric assay for dehalogenation reactivity of nanoscale zero-valent iron using 4-chlorophenol

    DEFF Research Database (Denmark)

    Hwang, Yuhoon; Mines, Paul D.; Jakobsen, Mogens Havsteen

    2015-01-01

    Despite the wide application of nanoscale zero valent iron (nZVI) for the treatment of a plethora of pollutants through reductive reactions, reactivity evaluation of nZVI towards dehalogenation has not been standardized. In this light, it was desired to develop a simple colorimetric assay...

  14. Development of a high-throughput colorimetric Zika virus infection assay.

    Science.gov (United States)

    Müller, Janis A; Harms, Mirja; Schubert, Axel; Mayer, Benjamin; Jansen, Stephanie; Herbeuval, Jean-Philippe; Michel, Detlef; Mertens, Thomas; Vapalahti, Olli; Schmidt-Chanasit, Jonas; Münch, Jan

    2017-04-01

    Zika virus (ZIKV) is an emerging pathogen that causes congenital infections which may result in birth defects, such as microcephaly. Currently, no approved treatment or vaccination is available. ZIKV can be readily detected in cell culture where virally infected cells are normally stained by specific antibodies. As ZIKV regularly causes a cytopathic effect, we were wondering whether this viral property can be used to quantitatively determine viral infectivity. We here describe the use of an 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazolium bromide-(MTT)-based cell viability assay that allows to determine ZIKV-induced cell death. We show that this colorimetric assay quantifies ZIKV infection over a broad range of viral dilutions in both monkey and human cells. It allows to determine inhibitory activities of antivirals that block ZIKV or to define the neutralizing antibody titers of ZIKV antisera. This MTT-based ZIKV detection assay can be evaluated by naked eye or computational tools, has a broad linear range, does not require large equipment or costly reagents, and thus represents a promising alternative to antibody-based assays, in particular in resource-poor settings. We propose to use this simple, fast, and cheap method for quantification of ZIKV neutralizing antibodies and testing of antiviral compounds.

  15. Active Immunization and Evaluation Against Luteinizing Hormone for Radioimmunoassay Technique in Human Serum

    International Nuclear Information System (INIS)

    Ebeid, N.H.; Shafik, H.M.; Ayoub, S.M.; Mehany, N.L.

    2014-01-01

    This study evaluated the antigenicity of luteinizing hormone conjugate with Bovine Serum Albumin (LH-BSA). The conjugation of LH- BSA was carried out by 1-Ethyl-3-(3-Dimethylaminopropyl) Carbodiimide HCl (ECDI). Three rabbits were immunized against LH-BSA. Two rabbits were immunized against nonconjugated LH and two rabbits against BSA only. Immunization was carried out through primary injection and 4 boosters. The preparation of the radioiodinated 125 I-LH was carried out using N- Bromo-Succinimide as oxidizing agent. The preparation of LH standards was carried out. The obtained LH antisera were characterized of titer, immuno response and displacement profile formulation, optimization and validation of the local liquid phase LH- Radioimmunoassay (RIA) system was carried out. The results provide a highly sensitive and accurate RIA system of LH-BSA. This technique could be used in measuring LH in human serum to investigate fertility especially disorders of the hypothalamic / pituitary / gonadal axis

  16. Human serum paraoxonase-1 (hPON1): in vitro inhibition effects of moxifloxacin hydrochloride, levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium.

    Science.gov (United States)

    Türkeş, Cüneyt; Söyüt, Hakan; Beydemir, Şükrü

    2015-01-01

    In this study, we investigated the effects of antibacterial drugs (moxifloxacin hydrochloride, levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium) on human serum paraoxonase-1 (hPON1) enzyme activity from human serum in vitro conditions. For this purpose, hPON1 enzyme was purified from human serum using simple chromatographic methods. The antibacterial drugs exhibited inhibitory effects on hPON1 at low concentrations. Ki constants were calculated to be 2.641 ± 0.040 mM, 5.525 ± 0.817 mM, 35.092 ± 1.093 mM, 252.762 ± 5.749 mM and 499.244 ± 10.149 mM, respectively. The inhibition mechanism of moxifloxacin hydrochloride was competitive, whereas levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium were noncompetitive inhibitors.

  17. Improved method and its clinical application of a radioimmunoassay of arginine vasopressin in human serum

    International Nuclear Information System (INIS)

    Wagner, H.; Maier, V.; Franz, H.W.; Ulm Univ.; Ulm Univ.

    1977-01-01

    A sensitive and specific double-antibody radioimmunoassay for measuring circulating levels of arginine vasopressin in human serum is described. It is possible to detect arginine vasopressin levels of 1 μU/ml serum without extraction procedure. Normal subjects were found to have 5.7 +- 4.4 μU/ml after a dehydration period of 12 hours. Water loading diminished arginine vasopressin concentrations while dehydration incrased it. Application of furosemide over a period of 14 days brought forth constant but not significant decreases. Subjects suffering from psychogenic polydipsia showed normal levels in spite of drinking 8-12 liters of water per day. Patients suffering from liver cirrhosis with ascites showed significantly higher arginine vasopressin levels, approaching normal values when ascites was under control. (orig.) [de

  18. Improved method and its clinical application of a radioimmunoassay of arginine vasopressin in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, H; Maier, V; Franz, H W [Ulm Univ. (Germany, F.R.). Abt. Endokrinologie und Stoffwechsel; Ulm Univ. (Germany, F.R.). Zentrum fuer Innere Medizin und Kinderheilkunde; Ulm Univ. (Germany, F.R.). Sektion Nephrologie)

    1977-05-01

    A sensitive and specific double-antibody radioimmunoassay for measuring circulating levels of arginine vasopressin in human serum is described. It is possible to detect arginine vasopressin levels of 1 ..mu..U/ml serum without extraction procedure. Normal subjects were found to have 5.7 +- 4.4 ..mu..U/ml after a dehydration period of 12 hours. Water loading diminished arginine vasopressin concentrations while dehydration incrased it. Application of furosemide over a period of 14 days brought forth constant but not significant decreases. Subjects suffering from psychogenic polydipsia showed normal levels in spite of drinking 8-12 liters of water per day. Patients suffering from liver cirrhosis with ascites showed significantly higher arginine vasopressin levels, approaching normal values when ascites was under control.

  19. Effects of Krill Oil on serum lipids of hyperlipidemic rats and human SW480 cells

    Directory of Open Access Journals (Sweden)

    Qian Wen-Bin

    2008-08-01

    Full Text Available Abstract Background Cardiovascular disease (CVD and colon cancer incidence are known to be closely related to dietary factors. This article evaluated effects of krill oil (KO on serum lipids of hyperlipidemia rats and human colon cancer cells (SW480. Serum lipids of rats fed with high fat diet (HFD and different doses of KO were measured by automatic analyzer. Effect of KO on viability of cells was determined by methyl thiazolyl tetrazolium (MTT assay. Results Except for higher dose group, body weights decreased significantly. Total cholesterol (TC, LDL-cholesterol (LDL-C of all dose groups, Triglycerides (TG of low and mid dose groups descended significantly, while there were no significant differences of HDL-cholesterol (HDL-C, compared with control group. Treatment of colon cancer cells with KO also resulted in time-dependent inhibition of cell growth. Conclusion Our findings indicated that the consumption of KO may provide benefits to control serum lipid levels in certain diseases and inhibit growth of colon cancer cells. Therefore, KO may be a good candidate for development as a functional food and nutraceutical.

  20. Interactions of Poly(amidoamine) Dendrimers with Human Serum Albumin: Binding Constants and Mechanisms

    OpenAIRE

    Giri, Jyotsnendu; Diallo, Mamadou S.; Simpson, André J.; Liu, Yi; Goddard, William A., III; Kumar, Rajeev; Woods, Gwen C.

    2011-01-01

    The interactions of nanomaterials with plasma proteins have a significant impact on their in vivo transport and fate in biological fluids. This article discusses the binding of human serum albumin (HSA) to poly(amidoamine) [PAMAM] dendrimers. We use protein-coated silica particles to measure the HSA binding constants (K_b) of a homologous series of 19 PAMAM dendrimers in aqueous solutions at physiological pH (7.4) as a function of dendrimer generation, terminal group, and core chemistry. To g...

  1. Serum urea and creatinine levels in Nigerian human malaria patients

    African Journals Online (AJOL)

    Serum urea and creatinine levels were determined in malaria patients infected with P. falciparum. Serum urea levels decreased significantly (P<0.05) in both mild (4.10 ±1.10 mmol/L) and moderate (4.40 ±1.40 mmol/L) parasitaemia when compared to control subjects (5.50 ±1.40 mmol/L). On the other hand, serum ...

  2. Normal human serum (HS) prevents oxidant-induced lysis of cultured endothelial cells (ECs)

    International Nuclear Information System (INIS)

    Callahan, K.S.; Harlan, J.M.

    1986-01-01

    Most studies demonstrating oxidant lysis of cultured ECs are performed in serum-free media or media containing low concentrations of bovine serum. The authors found that HS protects human and bovine ECs from lysis caused by reagent H 2 O 2 or glucose/glucose oxidase (GO)-generated H 2 O 2 . EC injury was assessed by 51 Cr release, cell detachment, or trypan blue dye exclusion. Protective HS activity was dose-dependent with concentrations greater than or equal to 25% preventing lethal injury. Cytotoxicity at 24 hrs, induced by 20 mU/ml GO, was 90.1 +/- 5.2% without HS vs 1.7 +/- 4.6% with 25% HS present (20 exp). Similar protection was observed with heparinized plasma. Of note, comparable concentrations of bovine serum were devoid of protective activity. Addition of fatty acid-free albumin to the media was also without protective effect. Preliminary characterization showed HS activity was stable to 60 0 C for 30 min, non-dialyzable at 25,000 MW cutoff, and retained in delipidated serum. The HS protection was not merely due to scavenging of exogenous H 2 O 2 as A23187-induced EC lysis was also prevented by HS. Protective activity was not reproduced by purified cerruloplasmin or transferrin. In conclusion, unidentified factor(s) present in HS protect cultured ECs from oxidant-induced lysis. Since endothelium is normally exposed to 100% plasma, the authors suggest that in vitro studies of oxidant-mediated injury be performed in the presence of HS. Factor(s) in HS may play an important role in modulating oxidant-induced vascular injury in vivo

  3. Trace analysis of icariin in human serum with dansyl chloride derivatization after oral administration of Epimedium decoction by liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Gong, Yinhan; Yip, See Chung; Thamarai, Sennappan Kanagamani; Zhang, Jie; Lee, Hian Kee; Yong, E L

    2007-12-15

    Epimedium herbs are a type of complex traditional Chinese medicine (TCM) with high estrogenic bioactivity. The Epimedium herbal decoction mixture contains many compounds including icariin that can exert potent effects on numerous physiological processes related to human health. An ultrasensitive liquid chromatography tandem mass spectrometric (LC-MS/MS) method has been developed to determine trace levels of icariin in human serum with dansyl chloride derivatization after oral administration of the Epimedium herbal decoctions. The dansyl-icariin showed an intense protonated molecular ion at m/z 910. The collision-induced dissociation of this ion formed a distinctive product at m/z 764, corresponding to a characteristic removal of a rhamnose sugar moiety of icariin. The selected reaction monitoring, based on the m/z 910-->764 transition, was highly specific and ultrasenstive for icariin in human serum samples. The lower limit of quantitation was 10 pg/mL icariin spiked into blank serum. The ranges of coefficients of variation for interday assays and intraday assays were 0-15.0% and 1.1-17.5%, respectively, for a wide linear range from 10 pg/mL to 4 ng/mL. This method was successfully applied to measure trace levels of icariin in a human serum after oral administration of Epimedium decoction within 48 h for the first time.

  4. The validation of the Z-Scan technique for the determination of plasma glucose

    Science.gov (United States)

    Alves, Sarah I.; Silva, Elaine A. O.; Costa, Simone S.; Sonego, Denise R. N.; Hallack, Maira L.; Coppini, Ornela L.; Rowies, Fernanda; Azzalis, Ligia A.; Junqueira, Virginia B. C.; Pereira, Edimar C.; Rocha, Katya C.; Fonseca, Fernando L. A.

    2013-11-01

    Glucose is the main energy source for the human body. The concentration of blood glucose is regulated by several hormones including both antagonists: insulin and glucagon. The quantification of glucose in the blood is used for diagnosing metabolic disorders of carbohydrates, such as diabetes, idiopathic hypoglycemia and pancreatic diseases. Currently, the methodology used for this determination is the enzymatic colorimetric with spectrophotometric. This study aimed to validate the use of measurements of nonlinear optical properties of plasma glucose via the Z-Scan technique. For this we used samples of calibrator patterns that simulate commercial samples of patients (ELITech ©). Besides calibrators, serum glucose levels within acceptable reference values (normal control serum - Brazilian Society of Clinical Pathology and Laboratory Medicine) and also overestimated (pathological control serum - Brazilian Society of Clinical Pathology and Laboratory Medicine) were used in the methodology proposal. Calibrator dilutions were performed and determined by the Z-Scan technique for the preparation of calibration curve. In conclusion, Z-Scan method can be used to determinate glucose levels in biological samples with enzymatic colorimetric reaction and also to apply the same quality control parameters used in biochemistry clinical.

  5. Osteocalcin as a negative regulator of serum leptin concentration in humans: insight from triathlon competitions.

    Science.gov (United States)

    Guadalupe-Grau, Amelia; Ara, Ignacio; Dorado, Cecilia; Vicente-Rodríguez, German; Perez-Gomez, Jorge; Cabrero, Javier Chavarren; Serrano-Sanchez, José A; Santana, Alfredo; Calbet, Jose A L

    2010-10-01

    Osteocalcin is a hormone produced by osteoblasts which acts as a negative regulator of fat mass, protecting against diet induced obesity and insulin resistance in rodents. To determine if an acute increase in osteocalcin concentration is associated with opposed changes in circulating leptin levels and insulin resistance we studied 15 middle and long distance male triathletes, (age 32.1 ± 6.9 years), before and 48 h after an Olympic (OT) or an Ironman (IT) triathlon competition. Muscle power, anaerobic capacity, body composition (dual-energy X-ray absorptiometry), and serum concentrations of testosterone, dihydrotestosterone, osteocalcin, leptin, glucose, insulin and insulin resistance (HOMA) were determined pre- and post-race. Pre- and 48 h post-race total and regional lean body mass was not altered, but fat mass was similarly increased (~250 g) 48 h after the competitions. This elicited an increase in plasma leptin of 33% after the IT while it remained unchanged after the OT, likely due to a 25% increase in plasma osteocalcin which occurred only after the OT (all p < 0.05). Post-race HOMA remained unchanged in OT and IT. Performance was normalized 48 h after the competitions, with the exception of a slightly lower jumping capacity after the IT. Serum testosterone concentration tended to decrease by 10% after the IT whilst dihydrotestosterone was reduced by 24% after the IT. In conclusion, an acute increase in serum osteocalcin concentration blunts the expected increase of serum leptin concentration that should occur with fat mass gain. This study provides evidence for osteocalcin as a negative regulator of serum leptin in humans.

  6. Ionization of tyrosine residues in human serum albumin and in its complexes with bilirubin and laurate

    DEFF Research Database (Denmark)

    Honoré, B; Brodersen, R

    1992-01-01

    Spectrophotometric titration of human serum albumin indicates that ionization of the 18 tyrosine residues takes place between pH 9 and 12.7. A Hill plot indicates that protons dissociate co-operatively from tyrosine residues, in pure albumin between pH 11.0 and 11.4 with a Hill coefficient 1.7, a...

  7. Human Serum Protein-Bound iodine and Protein Fractions at ...

    African Journals Online (AJOL)

    Iodine profile of Nigerians at different ages in both sexes and in pregnant women, and under narcotic influence, such as alcoholism, cigarette smoking and marijuana addiction were studied. Their serum total protein, albumin and globulin concentrations were also determined. Results of the study showed that serum protein ...

  8. Recombinant human serum albumin hydrogel as a novel drug delivery vehicle

    International Nuclear Information System (INIS)

    Hirose, Masaaki; Tachibana, Akira; Tanabe, Toshizumi

    2010-01-01

    Serum albumin acts as a physiological carrier for various compounds including drugs. A hydrogel consisting of recombinant human serum albumin (rHSA) was prepared to take advantage of drug binding ability of albumin for a sustained drug release carrier. The hydrogel was prepared by mixing rHSA and dithiothreitol and casted to a polystyrene mold. Hydrogel formation was thought to occur through the intermolecular interaction of the hydrophobic groups by protein denaturation. The release of sodium benzoate and salicylic acid from the hydrogel completed in 2 h, while warfarin release continued for 24 h. The total amounts of the drugs released from 100 mg of 15 and 5% rHSA hydrogel were 2.3 and 1.4 μmol for warfarin, 1.4 and 1.1 μmol for salicylic acid and 0.9 and 0.9 μmol for sodium benzoate. These results reflected the order of the binding ability of drugs for intact albumin indicating that the drug binding ability of HSA still remained after the hydrogel formation. However, fibroblast cells attached and proliferated well on the hydrogel, indicating that denaturation of rHSA proceeded to the extent to allow the cell attachment. The present rHSA hydrogel might be suitable for a sustained release carrier of drugs having affinity for albumin.

  9. Recombinant human serum albumin hydrogel as a novel drug delivery vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, Masaaki, E-mail: Hirose.Masaaki@mh.mt-pharma.co.jp [Advanced Medical Research Laboratory, Research Division, Mitsubishi Tanabe Pharma Corporation, 3-16-89 Kashima, Yodogawa-ku, Osaka 532-8505 (Japan); Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Tachibana, Akira; Tanabe, Toshizumi [Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan)

    2010-06-15

    Serum albumin acts as a physiological carrier for various compounds including drugs. A hydrogel consisting of recombinant human serum albumin (rHSA) was prepared to take advantage of drug binding ability of albumin for a sustained drug release carrier. The hydrogel was prepared by mixing rHSA and dithiothreitol and casted to a polystyrene mold. Hydrogel formation was thought to occur through the intermolecular interaction of the hydrophobic groups by protein denaturation. The release of sodium benzoate and salicylic acid from the hydrogel completed in 2 h, while warfarin release continued for 24 h. The total amounts of the drugs released from 100 mg of 15 and 5% rHSA hydrogel were 2.3 and 1.4 {mu}mol for warfarin, 1.4 and 1.1 {mu}mol for salicylic acid and 0.9 and 0.9 {mu}mol for sodium benzoate. These results reflected the order of the binding ability of drugs for intact albumin indicating that the drug binding ability of HSA still remained after the hydrogel formation. However, fibroblast cells attached and proliferated well on the hydrogel, indicating that denaturation of rHSA proceeded to the extent to allow the cell attachment. The present rHSA hydrogel might be suitable for a sustained release carrier of drugs having affinity for albumin.

  10. [Study on the interaction of doxycycline with human serum albumin].

    Science.gov (United States)

    Hu, Tao-Ying; Chen, Lin; Liu, Ying

    2014-05-01

    The present study was designed to investigate the interaction of doxycycline (DC) with human serum albumin (HSA) by the inner filter effects, displacement experiments and molecular docking methods, based on classic multi-spectroscopy. With fluorescence quenching method at 298 and 310 K, the binding constants Ka, were determined to be 2. 73 X 10(5) and 0. 74X 10(5) L mol-1, respectively, and there was one binding site between DC and HSA, indicating that the binding of DC to HSA was strong, and the quenching mechanism was a static quenching. The thermodynamic parameters (enthalpy change, AH and enthropy change, delta S) were calculated to be -83. 55 kJ mol-1 and -176. 31 J mol-1 K-1 via the Vant' Hoff equation, which indicated that the interaction of DC with HSA was driven mainly by hydrogen bonding and van der Waals forces. Based on the Föster's theory of non-radiation energy transfer, the specific binding distance between Trp-214 (acceptor) and DC (donor) was 4. 98 nm, which was similar to the result confirmed by molecular docking. Through displacement experiments, sub-domain IIA of HSA was assigned to possess the high-affinity binding site of DC. Three-dimensional fluorescence spectra indicated that the binding of DC to HSA induced the conformation change of HSA and increased the disclosure of some part of hydrophobic regions that had been buried before. The results of FTIR spectroscopy showed that DC bound to HSA led to the slight unfolding of the polypeptide chain of HSA. Furthermore, the binding details between DC and HSA were further confirmed by molecular docking methods, which revealed that DC was bound at sub-domain IIA through multiple interactions, such as hydrophobic effect, polar forces and pi-pi interactions. The experimental results provide theoretical basis and reliable data for the study of the interaction between small drug molecule and human serum albumin

  11. Aptamer-mediated colorimetric method for rapid and sensitive detection of chloramphenicol in food.

    Science.gov (United States)

    Yan, Chao; Zhang, Jing; Yao, Li; Xue, Feng; Lu, Jianfeng; Li, Baoguang; Chen, Wei

    2018-09-15

    We report an aptamer-mediated colorimetric method for sensitive detection of chloramphenicol (CAP). The aptamer of CAP is immobilized by the hybridization with pre-immobilized capture probe in the microtiter plate. The horseradish peroxidase (HRP) is covalently attached to the aptamer by the biotin-streptavidin system for signal production. CAP will preferably bind with aptamer due to the high binding affinity, which attributes to the release of aptamer and HRP and thus, affects the optical signal intensity. Quantitative determination of CAP is successfully achieved in the wide range from 0.001 to 1000 ng/mL with detection limit of 0.0031 ng/mL, which is more sensitive than traditional immunoassays. This method is further validated by measuring the recovery of CAP spiked in two different food matrices (honey and fish). The aptamer-mediated colorimetric method can be a useful protocol for rapid and sensitive screening of CAP, and may be used as an alternative means for traditional immunoassays. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Beetroot-pigment-derived colorimetric sensor for detection of calcium dipicolinate in bacterial spores.

    Directory of Open Access Journals (Sweden)

    Letícia Christina Pires Gonçalves

    Full Text Available In this proof-of-concept study, we describe the use of the main red beet pigment betanin for the quantification of calcium dipicolinate in bacterial spores, including Bacillus anthracis. In the presence of europium(III ions, betanin is converted to a water-soluble, non-luminescent orange 1∶1 complex with a stability constant of 1.4 × 10(5 L mol(-1. The addition of calcium dipicolinate, largely found in bacterial spores, changes the color of the aqueous solution of [Eu(Bn(+] from orange to magenta. The limit of detection (LOD of calcium dipicolinate is around 2.0 × 10(-6 mol L(-1 and the LOD determined for both spores, B. cereus and B. anthracis, is (1.1 ± 0.3× 10(6 spores mL(-1. This simple, green, fast and low cost colorimetric assay was selective for calcium dipicolinate when compared to several analogous compounds. The importance of this work relies on the potential use of betalains, raw natural pigments, as colorimetric sensors for biological applications.

  13. Pharmacokinetics and effects on serum cholinesterase activities of organophosphorus pesticides acephate and chlorpyrifos in chimeric mice transplanted with human hepatocytes.

    Science.gov (United States)

    Suemizu, Hiroshi; Sota, Shigeto; Kuronuma, Miyuki; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-11-01

    Organophosphorus pesticides acephate and chlorpyrifos in foods have potential to impact human health. The aim of the current study was to investigate the pharmacokinetics of acephate and chlorpyrifos orally administered at lowest-observed-adverse-effect-level doses in chimeric mice transplanted with human hepatocytes. Absorbed acephate and its metabolite methamidophos were detected in serum from wild type mice and chimeric mice orally administered 150mg/kg. Approximately 70% inhibition of cholinesterase was evident in plasma of chimeric mice with humanized liver (which have higher serum cholinesterase activities than wild type mice) 1day after oral administrations of acephate. Adjusted animal biomonitoring equivalents from chimeric mice studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and in vitro metabolic clearance data with a simple physiologically based pharmacokinetic (PBPK) model. Estimated plasma concentrations of acephate and chlorpyrifos in humans were consistent with reported concentrations. Acephate cleared similarly in humans and chimeric mice but accidental/incidental overdose levels of chlorpyrifos cleared (dependent on liver metabolism) more slowly from plasma in humans than it did in mice. The data presented here illustrate how chimeric mice transplanted with human hepatocytes in combination with a simple PBPK model can assist evaluations of toxicological potential of organophosphorus pesticides. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Structural analogs of human insulin-like growth factor I with reduced affinity for serum binding proteins and the type 2 insulin-like growth factor receptor

    International Nuclear Information System (INIS)

    Bayne, M.L.; Applebaum, J.; Chicchi, G.G.; Hayes, N.S.; Green, B.G.; Cascieri, M.A.

    1988-01-01

    Four structural analogs of human insulin-like growth factor I (hIGF-I) have been prepared by site-directed mutagenesis of a synthetic IGF-I gene and subsequent expression and purification of the mutant protein from the conditioned media of transformed yeast. [Phe -1 , Val 1 , Asn 2 , Gln 3 , His 4 , Ser 8 , His 9 , Glu 12 , Tyr 15 , Leu 16 ]IGF-I (B-chain mutant), in which the first 16 amino acids of hIGF-I were replaced with the first 17 amino acids of the B-chain of insulin, has >1000-, 100-, and 2-fold reduced potency for human serum binding proteins, the rat liver type 2 IGF receptor, and the human placental type 1 IGF receptor, respectively. The B-chain mutant also has 4-fold increased affinity for the human placental insulin receptor. [Gln 3 , Ala 4 ] IGF-I has 4-fold reduced affinity for human serum binding proteins, but is equipotent to hIGF-I at the types 1 and 2 IGF and insulin receptors. [Tyr 15 , Leu 16 ] IGH-I has 4-fold reduced affinity for human serum binding proteins and 10-fold increased affinity for the insulin receptor. The peptide in which these four-point mutations are combined, [Gln 3 , Ala 4 , Tyr 15 ,Leu 16 ]IGF-I, has 600-fold reduced affinity for the serum binding proteins. All four of these mutants stimulate DNA synthesis in the rat vascular smooth muscle cell line A10 with potencies reflecting their potency at the type 1 IGF receptor. These studies identify some of the domains of hIGF-I which are responsible for maintaining high affinity binding with the serum binding protein and the type 2 IGF receptor. In addition, These peptides will be useful in defining the role of the type 2 IGF receptor and serum binding proteins in the physiological actions of hIGF-I

  15. Determination Total Phosphour of Maize Plant Samples by Continuous Flow Analyzer in Comparison with Vanadium Molybdate Yellow Colorimetric Method

    Directory of Open Access Journals (Sweden)

    LIU Yun-xia

    2015-12-01

    Full Text Available The vanadium molybdate yellow colorimetric method(VMYC method is regarded as one of conventional methods for determining total phosphorus(P in plants, but it is time consuming procedure. Continuous flow analyzer(CFA is a fluid stream segmentation technique with air segments. It is used to measure P concentration based on the molybdate-antimony-ascorbic acid method of Murphy and Riley. Sixty nine of maize plant samples were selected and digested with H2SO4-H2O2. P concentrations in the digests were determined by CFA and VMYC method, respectively. The t test found that there was no any significant difference of the plant P contents measured by the CFA and the VMYC method. A linear equation could best describe their relationship: Y(CFA-P=0.927X(VMYC-P-0.002. The Pearson's correlation coefficient was 0.985 with a significance level(n=69, P<0.01. The CFA method for plant P measurement had a high precision with relative standard deviation(RSD less than 1.5%. It is suggested that the CFA based on Murphy and Riley colorimetric detection can be used to determinate total plant P in the digests solutions with H2SO4-H2O2. The CFA method is labor saving and can handle large numbers of samples. The human error in mixing with other operations is reduced to a great extent.

  16. Direct quantification of carotenoids in low fat babyfoods via laser photoacoustics and colorimetric index a

    NARCIS (Netherlands)

    Doka, O.; Ajtony, Z.; Bicanic, D.D.; Valinger, D.; Vegvari, G.

    2014-01-01

    Carotenoids are important antioxidants found in various foods including those for nutrition of infants. In this investigation, the total carotenoid content (TCC) of nine different commercially available baby foods was quantified using colorimetric index a * obtained via reflectance colorimetry (RC)

  17. Effect of Human and Bovine Serum Albumin on kinetic Chemiluminescence of Mn (III-Tetrakis (4-Sulfonatophenyl Porphyrin-Luminol-Hydrogen Peroxide System

    Directory of Open Access Journals (Sweden)

    Sayed Yahya Kazemi

    2012-01-01

    Full Text Available The present work deals with an attempt to study the effect of human and bovine serum albumin on kinetic parameters of chemiluminescence of luminol-hydrogen peroxide system catalyzed by manganese tetrasulfonatophenyl porphyrin (MnTSPP. The investigated parameters involved pseudo-first-order rise and fall rate constant for the chemiluminescence burst, maximum level intensity, time to reach maximum intensity, total light yield, and values of the intensity at maximum CL which were evaluated by nonlinear least square program KINFIT. Because of interaction of metalloporphyrin with proteins, the CL parameters are drastically affected. The systems resulted in Stern-Volmer plots with values of 3.17×105 and 3.7×105M−1 in the quencher concentration range of 1.5×10−6 to 1.5×10−5 M for human serum albumin (HSA and bovine serum albumin (BSA, respectively.

  18. Evaluation of serum lipids and lipoproteins as prognosticators in leukoplakia.

    Science.gov (United States)

    Ganavi, B S; Patil, Shankargouda; Rao, Roopa S

    2014-05-01

    Oral cancer is the 8th most common cancer worldwide. Squamous cell carcinomas constitute 94% of all oral malignancies and are often preceded by leukoplakia. Despite many adjunctive techniques to monitor transformation of leukoplakia to oral squamous cell carcinoma (OSCC), the mortality rate is on the rise. Incidentally, patients diagnosed with oral potentially malignant disorders (OPMDs) and oral cancers manifest with low choles-terol levels. Given a thought, hypolipidemia may be a useful adjunctive tool as it reflects the initial changes within the neo-plastic cells, thus giving a red alert in malignant transformation of leukoplakia at the earlier stage. To evaluate the feasibility of serum lipid profile as an adjunct early marker for malignant transformation of leukoplakia to OSCC. To estimate the serum cholesterol, triglycerides and lipoprotein (HDL, LDL, VLDL) levels in patients with leukoplakia, OSCC and age matched healthy control group. To compare the serum cholesterol, triglycerides and lipoprotein levels between patients of leukoplakia, OSCC and age matched healthy control group. The study group comprised of selected 30 individuals which included 10 each of histopathologically confirmed OSCC, leukoplakia and healthy controls. A written consent was taken from all of them, and a thorough case history was recorded and then venous blood was collected 12 hours post fasting and centrifuged. The serum cholesterol, triglycerides and HDL were estimated by enzymatic and colorimetric methods using commercially available kits--Roche/ Hitachi cobas systems. Chemistry assay QC procured from Bio-Rad was used as control. VLDL and LDL were derived from these values. Results were statistically analyzed using ANOVA and post hoc Tukey Test. Oral squamous cell carcinoma patients demonstrated significantly lower mean serum cholesterol level (151.60 mg/dl) than the control group (183.70 mg/dl). The mean cholesterol level in leukoplakia patients (173.90 mg/dl) was lower than that

  19. Microcontroller-based system for estimate of calcium in serum samples.

    Science.gov (United States)

    Neelamegam, Periyaswmy; Jamaludeen, Abdul Sheriff; Ragendran, Annamalai; Murugrananthan, Krishanamoorthy

    2010-01-01

    In this study, a microcontroller-based control unit was designed and constructed for the estimation of serum calcium in blood samples. The proposed optoelectronic instrument used a red light emitting diode (LED) as a light source and photodiode as a sensor. The performance of the system was compared with that of a commercial instrument in measuring calcium ion. The quantitative analysis of calcium in a catalyst using arsenazo III as colorimetric reagent was used to test the device. The calibration curve for calcium binding with arsenazo III was drawn to check the range of linearity, which was between 0.1 to 4.5 mM L⁻¹. The limit of detection (LOD) is 0.05 mM L⁻¹. Absorbance changes over the pH range of 2-12 were determined to optimize the assay, with maximum absorption at pH 9.0. Interferences in absorbance from monovalent (K+ and Na+) and divalent (Mg²+) cations were also studied. The results show that the system works successfully.

  20. Competitive binding of Chlorin p6 and Dansyl-L-Proline to Sudlow's site II of human serum albumin

    Science.gov (United States)

    Patel, Sunita; Sharma, Kaushal Kishor; Datta, Anindya

    2015-03-01

    The binding of chlorin p6, a model photosensitizer for photodynamic therapy (PDT), to the Sudlow's site II of Human Serum Albumin (HSA) has been monitored by different spectroscopic methods. Displacement of Dansyl-L-Proline (DP) from its conjugate with HSA is manifested in the spectral shift and decrease in its fluorescence intensity as well as the emergence of component with lifetime of 2-3 ns, which is characteristic of free DP. As DP is known to bind specifically to the Sudlow's site II of human serum albumin, its displacement by chlorin p6 indicates the residence of the photosensitizer in the same site, in addition to Sudlow's site I. The binding constants for Sudlow's site II, determined by the stopped-flow technique, are found to be two orders of magnitude smaller than that for Sudlow's site I.

  1. The development of a radioimmunoassay for reverse triiodothyronine sulfate in human serum and amniotic fluid

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Sing-Yung (Veterans Administration Medical Center, Long Beach, CA (United States)); Huang, Wen-Sheng; Chen, Wei-Lian (Tri-Service General Hospital, Taipei (Taiwan, Province of China)); Polk, D.; Reviczky, A.; Williams, J. III; Chopra, I.J.; Fisher, D.A. (Univ. of California, Los Angeles (United States))

    1993-06-01

    Sulfated iodothyronines including T[sub 4]-sulfate (T[sub 4]S) and T[sub 3]-sulfate (T[sub 3]S) have been identified in human serum and amniotic fluid. Little is know, however, about the existence of sulfate conjugation of reverse T[sub 3] (rT[sub 3]S) in man. In this report, the authors employed a novel, sensitive, and specific rT[sub 3]S RIA to address this question. The rabbit antiserum to rT[sub 3]S was highly specific; T[sub 4], T[sub 3], rT[sub 3], and 3,3'-T[sub 2] showed less than 0.002% cross-reaction with the antiserum. Only T[sub 4]S and T[sub 3]S cross-reacted significantly (0.3% and 0.01%, respectively); other analogs cross-reacted less than 0.0001%. The detection threshold of the RIA was 14 pmol/L (1.0 ng/dL). The mean serum rT[sub 3]S concentration (pmol/L) was 40 in euthyroid subjects. Values were similar in hypothyroid patients (38) and pregnant women (52) but significantly (P < 0.01) elevated to 176 in hyperthyroid patient, 74 in patients with nonthyroid illnesses, and 684 in cord sera of newborns. Serum rT[sub 3]S increased significantly in hyperthyroid patients 1 day after administration of 1 g sodium ipodate orally. Reverse T[sub 3]S was detected consistently in amniotic fluid at 14 to 22 weeks of gestation and showed a marked rise 1-3 weeks after intraamniotic administration of 500-1000 [mu]g T[sub 4]. The various data suggest that : (1) rT[sub 3]S is a normal component of human serum and amniotic fluid; (2) it is derived from metabolism of T[sub 4] or rT[sub 3]; (3) circulating rT[sub 3]S increases in hyperthyroidism and in circumstances where type I 5'-monodeiodinating activity is low, e.g. nonthyroid illnesses, fetal life, and after administration of ipodate. 20 refs., 4 figs.

  2. Density profile and cholesterol concentration of serum lipoproteins in experimental animals and human subjects on hypercholesterolaemic diets

    NARCIS (Netherlands)

    Beynen, A.C.; Terpstra, A.H.M.

    1984-01-01

    1. 1. The density profile of Sudan black stained serum lipoproteins was studied in human subjects and various animal species on diets supplemented with cholesterol. 2. 2. In the animals studied (rabbits, calves, mice, chickens, rats and guinea-pigs), the feeding of cholesterol resulted in an

  3. Preparation of rT3 in human serum ria kit

    International Nuclear Information System (INIS)

    Zhang Peixuan; Han Shiquan; Zhang Liling

    1991-02-01

    A method for the measurement of rT 3 in serum by radioimmunoassay is presented. The double antibody plus polyethylene glycol was used as separating reagent. The method is simple, precise and sensitive. Serum rT 3 values of normal (n = 61) were 47.7 ± 11.34 x 10 -8 g/L (X-bar ± SD). Patients with hyperthyroidism (n = 8) serum rT 3 values were 272.2 ± 91.1 x 10 -8 g/L (X-bar ± SD) and patients with hypothyroidism (n = 2) serum rT 3 values were 11.4 ± 8.3 x 10 -8 g/L (X-bar ± SD). It appears to be a useful diagnostic procedure for thyroid diseases

  4. Direct extraction of lead (II) from untreated human blood serum using restricted access carbon nanotubes and its determination by atomic absorption spectrometry.

    Science.gov (United States)

    Barbosa, Valéria Maria Pereira; Barbosa, Adriano Francisco; Bettini, Jefferson; Luccas, Pedro Orival; Figueiredo, Eduardo Costa

    2016-01-15

    Oxidized carbon nanotubes were covered with layers of bovine serum albumin to result in so-called restricted-access carbon nanotubes (RACNTs). This material can extract Pb(2+) ions directly from untreated human blood serum while excluding all the serum proteins. The RACNTs have a protein exclusion capacity of almost 100% and a maximum Pb(2+) adsorption capacity of 34.5mg g(-1). High resolution transmission electron microscopy, scanning transmission electron microscopy and energy dispersive spectroscopy were used to confirm the BSA layer and Pb(2+) adsorption sites. A mini-column filled with RACNTs was used in an on-line solid phase extraction system coupled to a thermospray flame furnace atomic absorption spectrometry. At optimized experimental conditions, the method has a detection limit as low as 2.1µg L(-1), an enrichment factor of 5.5, and inter- and intra-day precisions (expressed as relative standard deviation) of <8.1%. Recoveries of the Pb(2+) spiked samples ranged from 89.4% to 107.3% for the extraction from untreated human blood serum. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Use of magnesium silicate as a selective absorbent in radioimmunological method of determination of insulin level in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Bogoniowska, Z; Stelmasiak, T [Wojskowy Instytut Higieny i Epidemiologii, Warsaw (Poland)

    1974-01-01

    The authors present a radioimmunological method for determination of insulin (IRI) level in the human serum using magnesium silicate (talc) as adsorbent. The method is based on the phenomenon of selective adsorption of the free radioactive hormone. The optimal parameters for the method were determined. The serum level of IRI in clinically healthy subjects after oral glucose loading was established. The obtained results were compared with the results obtained by the radioimmunological method of double antibodies in stochastically grouped samples.

  6. Silver nanoplates-based colorimetric iodide recognition and sensing using sodium thiosulfate as a sensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xinyan; Chen, Shu, E-mail: chenshumail@gmail.com; Tang, Jian; Xiong, Yuan; Long, Yunfei, E-mail: l_yunfei927@163.com

    2014-05-01

    Highlights: • A new colorimetric iodide detection strategy based on triangular Ag nanoplate. • Sodium thiosulfate performed as a sensitizer. • Formation of insoluble AgI on the surface of Ag nanoplate. • This method has the advantages of good selectivity and high sensitivity. Abstract: A colorimetric method for the recognition and sensing of iodide ions (I⁻) has been developed by utilizing the reactions between triangular silver nanoplates (TAg-NPs) and I⁻ in the presence of sodium thiosulfate (Na₂S₂O₃). Specifically, I⁻ together with Na₂S₂O₃ can induce protection of TAg-NPs owing to the formation of insoluble AgI, as confirmed by the high-resolution transmission electron microscopy (HRTEM). In the absence of Na₂S₂O₃, the etching reactions on TAg-NPs were observed not only by I⁻ but also other halides ions. The Na₂S₂O₃ plays as a sensitizer in this system, which improved the selectivity and sensitivity. The desired colorimetric detection can be achieved by measuring the change of the absorption peak wavelength corresponding to localized surface plasmon resonance (LSPR) with UV–vis spectrophotometer or recognized by naked eye observation. The results show that the shift of the maximum absorption wavelength (Δλ) of the TAg-NPs/Na₂S₂O₃/I⁻ mixture was proportional to the concentration of I⁻ in the range 1.0 × 10⁻⁹–1.0 × 10⁻⁶ mol L⁻¹. Moreover, no other ions besides I⁻ can induce an eye discernible color change as low as 1.0 × 10⁻⁷ mol L⁻¹. Finally, this method was successfully applied for I⁻ determination in kelp samples.

  7. Determination of crenolanib in human serum and cerebrospinal fluid by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS).

    Science.gov (United States)

    Roberts, Michael S; Turner, David C; Owens, Thandranese S; Ramachandran, Abhijit; Wetmore, Cynthia; Throm, Stacy L; Stewart, Clinton F

    2013-06-15

    A LC-ESI-MS/MS method for the determination of crenolanib (CP-868,596) in human serum was developed and validated employing d4-CP-868,596 as an internal standard (ISTD). In addition to human serum, the method was also partially validated for crenolanib determination in human cerebrospinal fluid (CSF) samples. Sample aliquots (50μl of serum or CSF) were prepared for analysis using liquid-liquid extraction (LLE) with tert-butyl methyl ether. Chromatography was performed using a phenomenex Gemini C18 column (3μm, 100mm×4.6mm I.D.) in a column heater set at 50°C and an isocratic mobile phase (methanol/water/formic acid at a volume ratio of 25/25/0.15, v/v/v). The flow rate was 0.45mL/min, and the retention time for both analyte and ISTD was less than 3.5min. Samples were analyzed with an API-5500 LC-MS/MS system (ESI) in positive ionization mode coupled to a Shimadzu HPLC system. The ion transitions monitored were m/z 444.4→373.1 and m/z 448.2→374.2 for crenolanib and ISTD, respectively. The method was linear over the range of 5-1000ng/mL for serum and 0.5-1000ng/mL for CSF. For human serum, both intra-day and inter-day precision were <4%, while intra-day and inter-day accuracy were within 8% of nominal values. Recovery was greater than 50% for both the analyte and ISTD. For CSF samples, both intra-day and inter-day precision were <9% except at the lower limit of quantification (LLOQ) which was <17%. The intra-day and inter-day accuracy were within 11% of the nominal CSF concentrations. After validation, this method was successfully applied to the analysis of serial pharmacokinetic samples obtained from a child treated with oral crenolanib. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Radioimmunoassay of human calcitonin in serum and tissue from healthy individuals and patients with medullary carcinoma of the thyroid gland

    International Nuclear Information System (INIS)

    Gautvik, K.M.; Normann, T.; Teig, V.; Wille, S.Oe.; Brennhovd, I.O.; Christensen, I.

    1976-01-01

    A specific radioimmunological method for measurement of immunoreactive calcitonin (iCT) in human serum and tissue is described. Of healthy individuals of both sexes, 85 % had measurable iCT in serum (mean, 0.23 ng/ml). Of 29 patients who had received treatment for medullary carcinoma of the thyroid gland (MCT), 19 had increased serum iCT (0-60 ng/ml to205 ng/ml). Elevated serum iCT was also found preoperatively in 2 MCT patients. Eleven of the patients with abnormal elevations of serum iCT were alive 4 to 13 years after the operation. Concentration of iCT in extracts from MCT varied from 0.5 to 540 ng/ml wet weight. The diagnostic value of this method and its importance for pre- and post-operative evaluation of these patients are improved by the use of selective venous catheterization in basal state and during stimulation of CT secretion. (Auth.)

  9. HPLC-MS/MS method optimisation for matrix metalloproteinase 3 and matrix metalloproteinase 9 determination in human blood serum using target analysis.

    Science.gov (United States)

    Kotnik, Petra; Krajnc, Metka Koren; Pahor, Artur; Finšgar, Matjaž; Knez, Željko

    2018-02-20

    A quantitative analysis of zinc endopeptidases matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase 3 (MMP3) from human blood serum are presented. Both matrix metalloproteinases (MMP) are present in human blood serum and can be used as biomarkers for different diseases. The analysis was performed using LC-MS/MS with a triple quadrupole mass spectrometer, based on two specific peptides of each MMP in comparison with an enzyme-linked immunosorbent assay (ELISA). While the conditions for the LC-MS/MS analysis of MMP9 peptides were previously reported for bronchoalveolar lavage fluid, the analysis of MMP3 peptides was newly quantified for human blood serum herein for the first time. For MMP3, the linear behaviour was determined in the concentration range from 1.0-200.0ng/mL (R 2 =0.997) with an LLOD of 0.5ng/mL. For MMP9, linearity was determined in the concentration range from 6.5-65.0ng/mL (R 2 =0.995) with an LLOD of 2.0ng/mL. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Stereoselective Binding of Flurbiprofen Enantiomers and their Methyl Esters to Human Serum Albumin Studied by Time-Resolved Phosphorescence

    NARCIS (Netherlands)

    mr. Lammers, I.; Lhiaubet-Vallet, V.; Jimenez, M.C.; Ariese, F.; Miranda, M.A.; Gooijer, C.

    2012-01-01

    The interaction of the nonsteroidal anti-inflammatory drug flurbiprofen (FBP) with human serum albumin (HSA) hardly influences the fluorescence of the protein's single tryptophan (Trp). Therefore, in addition to fluorescence, heavy atom-induced room-temperature phosphorescence is used to study the

  11. Colorimetric Solid Phase Extraction (CSPE): Using Color to Monitor Spacecraft Water Quality

    Science.gov (United States)

    Gazda, Daniel B.; Nolan, Daniel J.; Rutz, Jeffrey A.; Schultz, John R.; Siperko, Lorraine M.; Porter, Marc D.; Lipert, Robert J.; Flint, Stephanie M.; McCoy, J. Torin

    2010-01-01

    In August 2009, an experimental water quality monitoring kit based on Colorimetric Solid Phase Extraction (CSPE) technology was delivered to the International Space Station (ISS). The kit, called the Colorimetric Water Quality Monitoring Kit (CWQMK), was launched as a Station Development Test Objective (SDTO) experiment to evaluate the suitability of CSPE technology for routine use monitoring water quality on the ISS. CSPE is a sorption-spectrophotometric technique that combines colorimetric reagents, solid-phase extraction, and diffuse reflectance spectroscopy to quantify trace analytes in water samples. In CSPE, a known volume of sample is metered through a membrane disk that has been impregnated with an analyte-specific colorimetric reagent and any additives required to optimize the formation of the analyte-reagent complex. As the sample flows through the membrane disk, the target analyte is selectively extracted, concentrated, and complexed. Formation of the analyte-reagent complex causes a detectable change in the color of the membrane disk that is proportional to the amount of analyte present in the sample. The analyte is then quantified by measuring the color of the membrane disk surface using a hand-held diffuse reflectance spectrophotometer (DRS). The CWQMK provides the capability to measure the ionic silver (Ag +) and molecular iodine (I2) in water samples on-orbit. These analytes were selected for the evaluation of CSPE technology because they are the biocides used in the potable water storage and distribution systems on the ISS. Biocides are added to the potable water systems on spacecraft to inhibit microbial growth. On the United States (US) segment of the ISS molecular iodine serves as the biocide, while the Russian space agency utilizes silver as a biocide in their systems. In both cases, the biocides must be maintained at a level sufficient to control bacterial growth, but low enough to avoid any negative effects on crew health. For example, the

  12. Serum albumin--a non-saturable carrier

    DEFF Research Database (Denmark)

    Brodersen, R; Honoré, B; Larsen, F G

    1984-01-01

    The shape of binding isotherms for sixteen ligands to human serum albumin showed no signs of approaching saturation at high ligand concentrations. It is suggested that ligand binding to serum albumin is essentially different from saturable binding of substrates to enzymes, of oxygen to haemoglobi...

  13. Molecular sex differences in human serum.

    Directory of Open Access Journals (Sweden)

    Jordan M Ramsey

    Full Text Available Sex is an important factor in the prevalence, incidence, progression, and response to treatment of many medical conditions, including autoimmune and cardiovascular diseases and psychiatric conditions. Identification of molecular differences between typical males and females can provide a valuable basis for exploring conditions differentially affected by sex.Using multiplexed immunoassays, we analyzed 174 serum molecules in 9 independent cohorts of typical individuals, comprising 196 males and 196 females. Sex differences in analyte levels were quantified using a meta-analysis approach and put into biological context using k-means to generate clusters of analytes with distinct biological functions. Natural sex differences were established in these analyte groups and these were applied to illustrate sexually dimorphic analyte expression in a cohort of 22 males and 22 females with Asperger syndrome. Reproducible sex differences were found in the levels of 77 analytes in serum of typical controls, and these comprised clusters of molecules enriched with distinct biological functions. Analytes involved in fatty acid oxidation/hormone regulation, immune cell growth and activation, and cell death were found at higher levels in females, and analytes involved in immune cell chemotaxis and other indistinct functions were higher in males. Comparison of these naturally occurring sex differences against a cohort of people with Asperger syndrome indicated that a cluster of analytes that had functions related to fatty acid oxidation/hormone regulation was associated with sex and the occurrence of this condition.Sex-specific molecular differences were detected in serum of typical controls and these were reproducible across independent cohorts. This study extends current knowledge of sex differences in biological functions involved in metabolism and immune function. Deviations from typical sex differences were found in a cluster of molecules in Asperger syndrome

  14. Bio-functionalized silver nanoparticles for selective colorimetric sensing of toxic metal ions and antimicrobial studies

    Science.gov (United States)

    Vinod Kumar, V.; Anbarasan, S.; Christena, Lawrence Rene; SaiSubramanian, Nagarajan; Philip Anthony, Savarimuthu

    2014-08-01

    Hibiscus Sabdariffa (Gongura) plant extracts (leaves (HL) and stem (HS) were used for the first time in the green synthesis of bio-functionalized silver nanoparticles (AgNPs). The bio-functionality of AgNPs has been successfully utilized for selective colorimetric sensing of potentially health and environmentally hazardous Hg2+, Cd2+ and Pb2+ metal ions at ppm level in aqueous solution. Importantly, clearly distinguishable colour for all three metal ions was observed. The influence of extract preparation condition and pH were also explored on the formation of AgNPs. Both selectivity and sensitivity differed for AgNPs synthesized from different parts of the plant. Direct correlation between the stability of green synthesized AgNPs at different pH and its antibacterial effects has been established. The selective colorimetric sensing of toxic metal ions and antimicrobial effect of green synthesized AgNPs demonstrated the multifunctional applications of green nanotechnology.

  15. Colorimetric detection of trace copper ions based on catalytic leaching of silver-coated gold nanoparticles.

    Science.gov (United States)

    Lou, Tingting; Chen, Lingxin; Chen, Zhaopeng; Wang, Yunqing; Chen, Ling; Li, Jinhua

    2011-11-01

    A colorimetric, label-free, and nonaggregation-based silver coated gold nanoparticles (Ag/Au NPs) probe has been developed for detection of trace Cu(2+) in aqueous solution, based on the fact that Cu(2+) can accelerate the leaching rate of Ag/Au NPs by thiosulfate (S(2)O(3)(2-)). The leaching of Ag/Au NPs would lead to dramatic decrease in the surface plasmon resonance (SPR) absorption as the size of Ag/Au NPs decreased. This colorimetric strategy based on size-dependence of nanoparticles during their leaching process provided a highly sensitive (1.0 nM) and selective detection toward Cu(2+), with a wide linear detection range (5-800 nM) over nearly 3 orders of magnitude. The cost-effective probe allows rapid and sensitive detection of trace Cu(2+) ions in water samples, indicating its potential applicability for the determination of copper in real samples.

  16. DNA-mediated strand displacement facilitates sensitive electronic detection of antibodies in human serums.

    Science.gov (United States)

    Dou, Baoting; Yang, Jianmei; Shi, Kai; Yuan, Ruo; Xiang, Yun

    2016-09-15

    We describe here the development of a sensitive and convenient electronic sensor for the detection of antibodies in human serums. The sensor is constructed by self-assembly formation of a mixed monolayer containing the small molecule epitope conjugated double stranded DNA probes on gold electrode. The target antibody binds the epitope on the dsDNA probe and lowers the melting temperature of the duplex, which facilitates the displacement of the antibody-linked strand of the duplex probe by an invading methylene blue-tagged single stranded DNA (MB-ssDNA) through the strand displacement reaction and leads to the capture of many MB-ssDNA on the sensor surface. Subsequent electrochemical oxidation of the methylene blue labels results in amplified current response for sensitive monitoring of the antibodies. The antibody assay conditions are optimized and the sensor exhibits a linear range between 1.0 and 25.0nM with a detection limit of 0.67nM for the target antibody. The sensor is also selective and can be employed to detect the target antibodies in human serum samples. With the advantages of using small molecule epitope as the antibody recognition element over traditional antigen, the versatile manipulability of the DNA probes and the unique properties of the electrochemical transduction technique, the developed sensor thus hold great potential for simple and sensitive detection of different antibodies and other proteins in real samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Human Epididymis Protein 4: A Novel Serum Inflammatory Biomarker in Cystic Fibrosis.

    Science.gov (United States)

    Nagy, Béla; Nagy, Béla; Fila, Libor; Clarke, Luka A; Gönczy, Ferenc; Bede, Olga; Nagy, Dóra; Újhelyi, Rita; Szabó, Ágnes; Anghelyi, Andrea; Major, Miklós; Bene, Zsolt; Fejes, Zsolt; Antal-Szalmás, Péter; Bhattoa, Harjit Pal; Balla, György; Kappelmayer, János; Amaral, Margarida D; Macek, Milan; Balogh, István

    2016-09-01

    Increased expression of the human epididymis protein 4 (HE4) was previously described in lung biopsy samples from patients with cystic fibrosis (CF). It remains unknown, however, whether serum HE4 concentrations are elevated in CF. Seventy-seven children with CF from six Hungarian CF centers and 57 adult patients with CF from a Czech center were enrolled. In addition, 94 individuals with non-CF lung diseases and 117 normal control subjects with no pulmonary disorders were analyzed. Serum HE4 levels were measured by using an immunoassay, and their expression was further investigated via the quantification of HE4 messenger RNA by using quantitative reverse transcription polymerase chain reaction in CF vs non-CF respiratory epithelium biopsy specimens. The expression of the potential regulator miR-140-5p was analyzed by using an UPL-based quantitative reverse transcription polymerase chain reaction assay. HE4 was measured in the supernatants from unpolarized and polarized cystic fibrosis bronchial epithelial cells expressing wild-type or F508del-CFTR. Median serum HE4 levels were significantly elevated in children with CF (99.5 [73.1-128.9] pmol/L) compared with control subjects (36.3 [31.1-43.4] pmol/L; P vs non-CF airway biopsy specimens. Twofold higher HE4 concentrations were recorded in the supernatant of polarized F508del-CF transmembrane conductance regulator/bronchial epithelial cells compared with wild-type cells. HE4 serum levels positively correlate with the overall severity of CF and the degree of pulmonary dysfunction. HE4 may thus be used as a novel inflammatory biomarker and possibly also as a measure of treatment efficacy in CF lung disease. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  18. Method for estimating effects of unknown correlations in spectral irradiance data on uncertainties of spectrally integrated colorimetric quantities

    Science.gov (United States)

    Kärhä, Petri; Vaskuri, Anna; Mäntynen, Henrik; Mikkonen, Nikke; Ikonen, Erkki

    2017-08-01

    Spectral irradiance data are often used to calculate colorimetric properties, such as color coordinates and color temperatures of light sources by integration. The spectral data may contain unknown correlations that should be accounted for in the uncertainty estimation. We propose a new method for estimating uncertainties in such cases. The method goes through all possible scenarios of deviations using Monte Carlo analysis. Varying spectral error functions are produced by combining spectral base functions, and the distorted spectra are used to calculate the colorimetric quantities. Standard deviations of the colorimetric quantities at different scenarios give uncertainties assuming no correlations, uncertainties assuming full correlation, and uncertainties for an unfavorable case of unknown correlations, which turn out to be a significant source of uncertainty. With 1% standard uncertainty in spectral irradiance, the expanded uncertainty of the correlated color temperature of a source corresponding to the CIE Standard Illuminant A may reach as high as 37.2 K in unfavorable conditions, when calculations assuming full correlation give zero uncertainty, and calculations assuming no correlations yield the expanded uncertainties of 5.6 K and 12.1 K, with wavelength steps of 1 nm and 5 nm used in spectral integrations, respectively. We also show that there is an absolute limit of 60.2 K in the error of the correlated color temperature for Standard Illuminant A when assuming 1% standard uncertainty in the spectral irradiance. A comparison of our uncorrelated uncertainties with those obtained using analytical methods by other research groups shows good agreement. We re-estimated the uncertainties for the colorimetric properties of our 1 kW photometric standard lamps using the new method. The revised uncertainty of color temperature is a factor of 2.5 higher than the uncertainty assuming no correlations.

  19. Experimental Germ Tube Induction in Candida albicans: An Evaluation of the Effect of Sodium Bicarbonate on Morphogenesis and Comparison with Pooled Human Serum

    Directory of Open Access Journals (Sweden)

    Tapiwa Matare

    2017-01-01

    Full Text Available Objective. The potential of NaHCO3 versus human serum to induce germ tube formation in Candida albicans was investigated. Specimens. A total of 100 isolates were obtained from oral swabs of patients presenting with thrush. Approval for the study was granted by the Joint Research Ethics Committee (JREC/23/08. Method. Confirmed C. albicans isolates by routine methods were tested for germ tube induction using 5 different concentrations of Tris-maleate buffered NaHCO3 and Tris-maleate buffer control. Standard control strains included were C. albicans (ATCC 10231 and C. krusei (ATCC 6258. Microculture was done in 20 μL inoculums on microscope slides for 3 hours at 37°C. The rate of germ tube formation at 10-minute intervals was determined on 100 isolates using the optimum 20 mM Tris-maleate buffered NaHCO3 concentration. Parallel germ tube formation using human serum was done in test tubes. Results. The optimum concentration of NaHCO3 in Tris-maleate buffer for germ tube induction was 20 mM for 67% of isolates. Only 21% of isolates formed germ tubes in Tris-maleate buffer control. There was no significant difference in induction between human serum and Tris-maleate buffered NaHCO3. Conclusion. Tris-maleate buffered NaHCO3 induced germ tube formation in C. albicans isolates at rates similar to human serum.

  20. Determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of water-soluble tetrazolium salts.

    Science.gov (United States)

    Tsukatani, Tadayuki; Suenaga, Hikaru; Ishiyama, Munetaka; Ezoe, Takatoshi; Matsumoto, Kiyoshi

    2011-07-15

    A method for the determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of the tetrazolium salt {2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8)} via 2-methyl-1,4-napthoquinone (NQ) was developed. Measurement conditions were optimized for the microbiological determination of water-soluble vitamins, such as vitamin B(6), biotin, folic acid, niacin, and pantothenic acid, using microorganisms that have a water-soluble vitamin requirement. A linear relationship between absorbance and water-soluble vitamin concentration was obtained. The proposed method was applied to determine the concentration of vitamin B(6) in various foodstuffs. There was good agreement between vitamin B(6) concentrations determined after 24h using the WST-8 colorimetric method and those obtained after 48h using a conventional method. The results suggest that the WST-8 colorimetric assay is a useful method for the rapid determination of water-soluble vitamins in a 96-well microtiter plate. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. A meta-analysis of the association of serum ischaemia-modified albumin levels with human hypothyroidism and hyperthyroidism.

    Science.gov (United States)

    Reddy, Varikasuvu Seshadri; Bukke, Suman; Mahato, Khageshwar; Kumar, Vinod; Reddy, Netala Vasudeva; Munikumar, Manne; Vodelu, Bramahanapally

    2017-02-28

    Serum levels of ischaemia-modified albumin (IMA) have been studied as a novel and simple measure of oxidative stress (OXS) in different thyroid pathologies. However, results of available studies in the literature were not consistent. This meta-analysis was attempted to quantify the overall effect size for serum IMA levels in human hypothyroidism (HT) and hyperthyroidism (HYT) and to study its associations with the thyroid profile. Databases of PubMed/Medline, EMBASE, Google Scholar, Web of Science and Science Direct were searched for articles. Data on serum IMA levels in HT, HYT patients and euthyroid controls were extracted to compute standardized mean differences (SMD) by the random-effects model. The associations between IMA and thyroid profile were computed by the meta-analysis of correlation coefficients. IMA levels in HT patients (SMD=1.12; Z=2.76; P=0.006) and HYT patients (SMD=1.64; Z=2.57; P=0.01) were significantly higher than in euthyroid controls and the thyroid treatment showed a favourble effect on serum IMA levels. There were strong and significant correlations between IMA and hormonal status in HT and HYT groups. This meta-analysis showing increased IMA level in both HT and HYT patients and its association with thyroid profile suggests that serum IMA could be used as a simple measure of increased OXS in thyroid dysfunction. © 2017 The Author(s).

  2. Human serum-derived protein removes the need for coating in defined human pluripotent stem cell culture

    Science.gov (United States)

    Pijuan-Galitó, Sara; Tamm, Christoffer; Schuster, Jens; Sobol, Maria; Forsberg, Lars; Merry, Catherine L. R.; Annerén, Cecilia

    2016-01-01

    Reliable, scalable and time-efficient culture methods are required to fully realize the clinical and industrial applications of human pluripotent stem (hPS) cells. Here we present a completely defined, xeno-free medium that supports long-term propagation of hPS cells on uncoated tissue culture plastic. The medium consists of the Essential 8 (E8) formulation supplemented with inter-α-inhibitor (IαI), a human serum-derived protein, recently demonstrated to activate key pluripotency pathways in mouse PS cells. IαI efficiently induces attachment and long-term growth of both embryonic and induced hPS cell lines when added as a soluble protein to the medium at seeding. IαI supplementation efficiently supports adaptation of feeder-dependent hPS cells to xeno-free conditions, clonal growth as well as single-cell survival in the absence of Rho-associated kinase inhibitor (ROCKi). This time-efficient and simplified culture method paves the way for large-scale, high-throughput hPS cell culture, and will be valuable for both basic research and commercial applications. PMID:27405751

  3. Serum homocysteine, folate, vitamin B12 and total antioxidant status in vegetarian children.

    Science.gov (United States)

    Ambroszkiewicz, J; Klemarczyk, W; Chełchowska, M; Gajewska, J; Laskowska-Klita, T

    2006-01-01

    The results of several studies point to the positive role of vegetarian diets in reducing the risk of diabetes, some cancers and cardiovascular diseases. However, exclusion of animal products in vegetarian diets may affect the cobalamin status and cause an elevation of the plasma homocysteine level. The aim of this study was to assess the effect of vegetarian diets on serum concentrations of homocysteine, folate, vitamin B12 and total antioxidant status (TAS) in children. The study included 32 vegetarians (including 5 vegans), age 2-10 years. Dietary constituents were analyzed using a local nutritional programme. Serum homocysteine, folate and vitamin B12 were determined with fluorescence and chemiluminescence immunoassays. The concentration of TAS was measured by a colorimetric method. Average daily energy intake and the percentage of energy from protein, fat and carbohydrates in the diets of the studied children were just above or similar to the recommended amounts. It could be shown that vegetarian diets contain high concentrations of folate. In vegan diets it even exceeds the recommended dietary allowance. Mean daily intake of vitamin B12 in the studied diets was adequate but in vegans was below the recommended range. The serum concentrations of homocysteine, folate, vitamin B12 and TAS in vegetarian children remained within the physiological range. The presented data indicate that vegetarian children, contrary to adults, have enough vitamin B12 in their diet (excluding vegans) and normal serum concentrations of homocysteine, folate and vitamin B12. Therefore, in order to prevent deficiencies in the future, close monitoring of vegetarian children (especially on a vegan diet) is important to make sure that they receive adequate quantities of nutrients needed for healthy growth.

  4. Measurement of tamsulosin in human serum by liquid chromatography–tandem mass spectrometry☆

    Science.gov (United States)

    Upreti, Rita; Homer, Natalie Z.M.; Naredo, Gregorio; Cobice, Diego F.; Hughes, Katherine A.; Stewart, Laurence H.; Walker, Brian R.; Andrew, Ruth

    2013-01-01

    A simple, sensitive and robust method to extract tamsulosin from human serum, and quantify by liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed and validated and is applicable as a measure of compliance in clinical research. Tamsulosin was extracted from human serum (100 μL) via liquid–liquid extraction with methyl tert-butyl ether (2 mL) following dilution with 0.1 M ammonium hydroxide (100 μL), achieving 99.9% analyte recovery. Internal standard, d9-finasteride, was synthesised in-house. Analyte and internal standard were separated on an Ascentis® Express C18 (100 mm × 3 mm, 2.7 μm) column using a gradient elution with mobile phases methanol and 2 mM aqueous ammonium acetate (5:95, v/v). Total run-time was 6 min. Tamsulosin was quantified using a triple quadrupole mass spectrometer operated in multi-reaction-monitoring (MRM) mode using positive electrospray ionisation. Mass transitions monitored for quantitation were: tamsulosin m/z 409 → 228 and d9-finasteride m/z 382 → 318, with the structural formulae of ions confirmed by Fourier transform ion cyclotron resonance mass spectrometry (within 10 ppm). The limit of quantitation was 0.2 ng/mL, and the method was validated in the linear range 0.2–50 ng/mL with acceptable inter- and intra-assay precision and accuracy and stability suitable for routine laboratory practice. The method was successfully applied to samples taken from research volunteers in a clinical study of benign prostatic hyperplasia. PMID:23743242

  5. Colorimetric assay of copper ions based on the inhibition of peroxidase-like activity of MoS2 nanosheets

    Science.gov (United States)

    Chen, Huan; Li, Zhihong; Liu, Xueting; Zhong, Jianhai; Lin, Tianran; Guo, Liangqia; Fu, Fengfu

    2017-10-01

    The peroxidase-like catalytic activity of MoS2 nanomaterials has been utilized for colorimetric bioassays and medical diagnostics. However, the application of peroxidase-like catalytic activity of MoS2 nanomaterials in environmental analysis was seldom explored. Herein, copper ions were found to inhibit the peroxidase-like catalytic activity of MoS2 nanosheets, which can catalyze the oxidation of 3, 3‧, 5, 5‧-tetramethylbenzidine by H2O2 to produce a colorimetric product. Based on this finding, a simple sensitive colorimetric method for the detection of copper ions was developed. In the presence of copper ions, the absorbance and color of the solution decreased with the increasing concentration of copper ions. The color of the solution can be used to semi-quantitative on-site assay of copper ions by naked eyes. A linear relationship between the absorbance and the concentration of copper ions was observed in the range of 0.4-4.0 μmol L- 1 with a detection limit of 92 nmol L- 1, which was much lower than the maximum contaminant level of copper in drinking water legislated by the Environmental Protection Agency of USA and the World Health Organization. The method was applied to detect copper ions in environmental water samples with satisfactory results.

  6. Prognostic significance of serum antibodies to human papillomavirus-16 E4 and E7 peptides in cervical cancer

    NARCIS (Netherlands)

    Gaarenstroom, K. N.; Kenter, G. G.; Bonfrer, J. M.; Korse, C. M.; Gallee, M. P.; Hart, A. A.; Müller, M.; Trimbos, J. B.; Helmerhorst, T. J.

    1994-01-01

    BACKGROUND: The objective of this study was to investigate the prognostic significance of serum antibodies to human papillomavirus (HPV)-16 peptides in patients with squamous cell cervical cancer. METHODS: Pretreatment sera from 78 patients and 198 control women were tested by an enzyme-linked

  7. Serum protein inhibition of thyrotropin binding to human thyroid tissue

    International Nuclear Information System (INIS)

    Beall, G.N.; Chopra, I.J.; Solomon, D.H.; Kruger, S.R.

    1978-01-01

    We used a modificaton of the TSH radioreceptor assay to detect TSH-binding inhibition (TBI) activity in serum and serum fractions from normal subjects and patients with Graves' disease. TBI activity is present in normal IgG prepared by DEAE-Sephadex chromatography and in normal globulins prepared by precipitation at 1.6 M ammonium sulfate. Other normal serum proteins also had TBI activity when large concentrations were tested. Gel filtration chromatography and powder block electrophoresis were used to prepare fractions of normal and Graves' disease sera. In these fractions from normal serum, TBI activity was found in both γ-globulin and α-globulin-albumin fractions electrophoretically and in both 7S and 4S peaks from gel filtration. TBI activity from Graves' disease patients' sera was similarly distributed, but relatively more TBI accompanied the electrophoretic γ-globulins. Sepharose Protein-A and anti-IgG were used as immunoabsorbents to isolate and purify IgG from normal and Graves' disease sera. TBI activity in IgG was proportional to the IgG concentration, indicating that the TBI which migrates as a γ-globulin electrophoretically is an IgG and thus may possibly be an antibody. Inhibitory activity found in normal serum globulins and in the non-IgG fractions of both normal and abnormal sera seriously interferes with attempts to use the TSH radioreceptor assay to study the hypothesized anti-TSH receptor antibody in the serum of patients with Graves' disease

  8. Biotransformation of endorphins by a synaptosomal plasma membrane preparation of rat brain and by human serum

    NARCIS (Netherlands)

    Burbach, J.P.H.; Loeber, J.G.; Verhoef, J.; Kloet, E.R. de; Wied, D. de

    1979-01-01

    β-Endorphin (β-LPH 61–91), γ-endorphin (61–77), des-tyrosine-γ-endorphin (62–77), α-endorphin (61–76), and β-LPH 61–69 either labeled with [125I] at the N-terminal 61-tyrosine residue or unlabeled were incubated with a crude synaptosomal plasma membrane fraction of rat brain or in human serum. At

  9. A Rapid Colorimetric Method Reveals Fraudulent Substitutions in Sea Urchin Roe Marketed in Sardinia (Italy).

    Science.gov (United States)

    Meloni, Domenico; Spina, Antonio; Satta, Gianluca; Chessa, Vittorio

    2016-06-25

    In recent years, besides the consumption of fresh sea urchin specimens, the demand of minimally-processed roe has grown considerably. This product has made frequent consumption in restaurants possible and frauds are becoming widespread with the partial replacement of sea urchin roe with surrogates that are similar in colour. One of the main factors that determines the quality of the roe is its colour and small differences in colour scale cannot be easily discerned by the consumers. In this study we have applied a rapid colorimetric method for reveal the fraudulent partial substitution of semi-solid sea urchin roe with liquid egg yolk. Objective assessment of whiteness (L*), redness (a*), yellowness (b*), hue (h*), and chroma (C*) was carried out with a digital spectrophotometer using the CIE L*a*b* colour measurement system. The colorimetric method highlighted statistically significant differences among sea urchin roe and liquid egg yolk that could be easily discerned quantitatively.

  10. A high-throughput colorimetric assay for glucose detection based on glucose oxidase-catalyzed enlargement of gold nanoparticles

    Science.gov (United States)

    Xiong, Yanmei; Zhang, Yuyan; Rong, Pengfei; Yang, Jie; Wang, Wei; Liu, Dingbin

    2015-09-01

    We developed a simple high-throughput colorimetric assay to detect glucose based on the glucose oxidase (GOx)-catalysed enlargement of gold nanoparticles (AuNPs). Compared with the currently available glucose kit method, the AuNP-based assay provides higher clinical sensitivity at lower cost, indicating its great potential to be a powerful tool for clinical screening of glucose.We developed a simple high-throughput colorimetric assay to detect glucose based on the glucose oxidase (GOx)-catalysed enlargement of gold nanoparticles (AuNPs). Compared with the currently available glucose kit method, the AuNP-based assay provides higher clinical sensitivity at lower cost, indicating its great potential to be a powerful tool for clinical screening of glucose. Electronic supplementary information (ESI) available: Experimental section and additional figures. See DOI: 10.1039/c5nr03758a

  11. Renal targeted delivery of triptolide by conjugation to the fragment peptide of human serum albumin.

    Science.gov (United States)

    Yuan, Zhi-xiang; Wu, Xiao-juan; Mo, Jingxin; Wang, Yan-li; Xu, Chao-qun; Lim, Lee Yong

    2015-08-01

    We have previously demonstrated that peptide fragments (PFs) of the human serum albumin could be developed as potential renal targeting carriers, in particular, the peptide fragment, PF-A299-585 (A299-585 representing the amino acid sequence of the human serum albumin). In this paper, we conjugated triptolide (TP), the anti-inflammatory Chinese traditional medicine, to PF-A299-585 via a succinic acid spacer to give TPS-PF-A299-585 (TP loading 2.2% w/w). Compared with the free TP, TPS-PF-A299-585 exhibited comparable anti-inflammatory activity in the lipopolysaccharide stimulated MDCK cells, but was significantly less cytotoxic than the free drug. Accumulation of TPS-PF-A299-585 in the MDCK cells in vitro and in rodent kidneys in vivo was demonstrated using FITC-labeled TPS-PF-A299-585. Renal targeting was confirmed in vivo in a membranous nephropathic (MN) rodent model, where optical imaging and analyses of biochemical markers were combined to show that TPS-PF-A299-585 was capable of alleviating the characteristic symptoms of MN. The collective data affirm PF-A299-585 to be a useful carrier for targeting TP to the kidney. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. [Determination of ferulic acid absorbed into human serum from oral decoction of rhizoma chuanxiong and pharmacokinetic study of ferulic acid].

    Science.gov (United States)

    Sun, S; Huang, X; Zhang, L; Ren, P; Chang, Z

    2001-10-01

    To improve the HPLC method for determining ferulic acid(FA) in the human serum and to research FA clinical pharmacokinetics. Serum concentrations of FA were determined by HPLC using methanol-water-acetic acid (40:59.7:0.3, v/v) as the mobile phase and the column packed with ODS (150 mm x 4.6 mm, 5 microns) as a fixed phase and the flow rate was 1.0 ml/min. FA was detected at 320 nm wave length. The internal standard was coumarin. The serum samples were treated by the water-boiling method. Peak of FA in serum was recognized by photodiode-array detection. FA and internal standard were separated completely under the condition described as above. FA was linear in the range of (40.16-8032 ng/ml) (r = 0.9975). The CV was less than 10%, the average recovery was 100.3%, and the limit concentration in serum was 25.1 ng/ml. PK was in accordance with open bicameral model. This method can be applied to clinical pharmacokinetic study of FA.

  13. Concentrations of arsenic in brackish lake water : Application of tristimulus colorimetric determination

    OpenAIRE

    Rahman, Md. Mustafizur; Seike, Yasushi; Okumura, Minoru

    2006-01-01

    The evaluation of a simple and rapid tristimulus colorimetric method for the determination of arsenic in brackish waters and its application to brackish water samples taken from brackish Lake Nakaumi are described. The determinations of arsenic in brackish water samples were made satisfactorily independent of sample salinity. By applying this method to lake water samples, the distributions and behaviors of arsenic in the lake and their controlling factors were clarified, such as seasonal vari...

  14. Colorimetric Analysis on Flocculation of Bioinspired Au Self-Assembly for Biophotonic Application

    Directory of Open Access Journals (Sweden)

    Wan-Joong Kim

    2009-01-01

    Full Text Available Gold nanoparticles exhibited strong surface plasmon absorption and couplings between neighboring particles within bioactivated self-assembly modified their optical properties. Colorimetric analysis on the optical modification of surface plasmon resoanance (SPR shift and flocculation parameter functionalized bioinspired gold assembly for biophotonic application. The physical origin of bioinspired gold aggregation-induced shifting, decreasing, or broadening of the plasmon absorption spectra could be explained in terms of dynamic depolarization, collisional damping, and shadowing effects.

  15. HPMA-based drug delivery system and its interactions of human serum albumin: SAXS, ITC, and NMR study

    Czech Academy of Sciences Publication Activity Database

    Filippov, Sergey K.; Kaberov, Leonid; Zhang, X.; Niebuur, B.-J.; Chytil, Petr; Etrych, Tomáš; Wieland, F.; Velychkivska, Nadiia; Starovoytova, Larisa; Svergun, D.; Papadakis, C.

    2017-01-01

    Roč. 254, 20 August (2017), s. 455 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] R&D Projects: GA ČR(CZ) GC15-10527J Institutional support: RVO:61389013 Keywords : HPMA * human serum albumin * SAXS Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry

  16. Ternary mixed-mode silica sorbent of solid-phase extraction for determination of basic, neutral and acidic drugs in human serum.

    Science.gov (United States)

    Jin, Shupei; Qiao, Yinghua; Xing, Jun

    2018-06-01

    In this study, a ternary mixed-mode silica sorbent (TMSS) with octamethylene, carboxyl, and amino groups was prepared via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction and a subsequent reduction of azide to primary amine. While used in solid-phase extraction (SPE), the retention behavior of TMSS towards a total of nine kinds of basic, neutral, and acidic drugs was investigated in detail. The results revealed that hydrophobic, ion-exchange interaction, and electrostatic repulsion between TMSS and the analytes were closely related to the retention behavior of TMSS. Besides, the log K ow value of the analyte was also a factor influencing the retention behavior of analytes on TMSS. The nine analytes could be retained by TMSS simultaneously and then, were eluted into two fractions according to the acid-base property of the analytes for further determinations. The acidic and neutral analytes were in one fraction, and the basic ones in the other fraction. When used to treat the human serum spiked with the nine drugs, TMSS offered higher recoveries than BakerBond CBA and comparable recoveries to Oasis WCX. It should be noted TMSS had better purifying capability for human serum than Oasis WCX. Under the optimized SPE conditions, a method of SPE hyphenated to high-performance liquid chromatography-ultraviolet detection (HPLC-UV) for determination of the basic, neutral, and acidic drugs spiked in human serum was established. For the nine drugs, the linear ranges were all between 5.0 and 1000 μg L -1 with correlation coefficients (R 2 ) above 0.9990, and the limits of detection (LODs) were in the range of 0.8-2.3 μg L -1 . The intra-day and inter-day relative standard deviations (RSDs) were less than 5.3 and 8.8%, respectively. Graphical abstract Treating drugs in human serum by SPE with ternary mixed-mode silica sorbent.

  17. A one-step separation of human serum high density lipoproteins 2 and 3 by rate-zonal density gradient ultracentrifugation in a swinging bucket rotor

    NARCIS (Netherlands)

    Groot, P.H.E.; Scheek, L.M.; Havekes, L.; Noort, W.L. van; Hooft, F.M. van 't

    1982-01-01

    A method was developed for the separation of the high density lipoprotein subclasses HDL2 and HDL3 from human serum. Six serum samples are fractionated in a single-step ultracentrifugal procedure using the Beckman (SW-40) swinging bucket rotor. The method is based on a difference in flotation rate

  18. Selective Distance-Based K+ Quantification on Paper-Based Microfluidics.

    Science.gov (United States)

    Gerold, Chase T; Bakker, Eric; Henry, Charles S

    2018-04-03

    In this study, paper-based microfluidic devices (μPADs) capable of K + quantification in aqueous samples, as well as in human serum, using both colorimetric and distance-based methods are described. A lipophilic phase containing potassium ionophore I (valinomycin) was utilized to achieve highly selective quantification of K + in the presence of Na + , Li + , and Mg 2+ ions. Successful addition of a suspended lipophilic phase to a wax printed paper-based device is described and offers a solution to current approaches that rely on organic solvents, which damage wax barriers. The approach provides an avenue for future alkali/alkaline quantification utilizing μPADs. Colorimetric spot tests allowed for K + quantification from 0.1-5.0 mM using only 3.00 μL of sample solution. Selective distance-based quantification required small sample volumes (6.00 μL) and gave responses sensitive enough to distinguish between 1.0 and 2.5 mM of sample K + . μPADs using distance-based methods were also capable of differentiating between 4.3 and 6.9 mM K + in human serum samples. Distance-based methods required no digital analysis, electronic hardware, or pumps; any steps required for quantification could be carried out using the naked eye.

  19. Polycaprolactone-Polydiacetylene Electrospun Fibers for Colorimetric Detection of Fake Gasoline

    Directory of Open Access Journals (Sweden)

    Shamshad Ali

    2016-04-01

    Full Text Available PCDA (Pentacosadiynoic Acid monomers were successfully embedded in PCL (Poly ?-Caprolactone polymer matrix by electrospinning process for the first time. The resultant EFM (Electrospun Fibers Mat was photo-polymerized under 254 nm UV light that enables colorimetric detection of fake gasoline. Results revealed that the fake gasoline develops a red color mat within 5 sec. FE-SEM images showed that the fake gasoline treatment dissolved the PCL EFM that give access to interact with PDA polymer. The proposed litmus-type sensor based on PCL-PDA EFM is highly sensitive to fake gasoline and can be fabricated easily

  20. The development of a radioimmunoassay for reverse triiodothyronine sulfate in human serum and amniotic fluid

    International Nuclear Information System (INIS)

    Wu, Sing-Yung; Huang, Wen-Sheng; Chen, Wei-Lian; Polk, D.; Reviczky, A.; Williams, J. III; Chopra, I.J.; Fisher, D.A.

    1993-01-01

    Sulfated iodothyronines including T 4 -sulfate (T 4 S) and T 3 -sulfate (T 3 S) have been identified in human serum and amniotic fluid. Little is know, however, about the existence of sulfate conjugation of reverse T 3 (rT 3 S) in man. In this report, the authors employed a novel, sensitive, and specific rT 3 S RIA to address this question. The rabbit antiserum to rT 3 S was highly specific; T 4 , T 3 , rT 3 , and 3,3'-T 2 showed less than 0.002% cross-reaction with the antiserum. Only T 4 S and T 3 S cross-reacted significantly (0.3% and 0.01%, respectively); other analogs cross-reacted less than 0.0001%. The detection threshold of the RIA was 14 pmol/L (1.0 ng/dL). The mean serum rT 3 S concentration (pmol/L) was 40 in euthyroid subjects. Values were similar in hypothyroid patients (38) and pregnant women (52) but significantly (P 3 S increased significantly in hyperthyroid patients 1 day after administration of 1 g sodium ipodate orally. Reverse T 3 S was detected consistently in amniotic fluid at 14 to 22 weeks of gestation and showed a marked rise 1-3 weeks after intraamniotic administration of 500-1000 μg T 4 . The various data suggest that : (1) rT 3 S is a normal component of human serum and amniotic fluid; (2) it is derived from metabolism of T 4 or rT 3 ; (3) circulating rT 3 S increases in hyperthyroidism and in circumstances where type I 5'-monodeiodinating activity is low, e.g. nonthyroid illnesses, fetal life, and after administration of ipodate. 20 refs., 4 figs