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Sample records for preparative scale hplc

  1. HPLC-DAD and HPLC-ESI-MS analyses of Tiliae flos and its preparations.

    Science.gov (United States)

    Karioti, A; Chiarabini, L; Alachkar, A; Fawaz Chehna, M; Vincieri, F F; Bilia, A R

    2014-11-01

    In the present study extensive HPLC-DAD, HPLC-ESI-MS and NMR analyses were undertaken in the aqueous preparations (decoctions, infusions) and tinctures of Tilia platyphyllos Scop inflorescences. The aim of this work was to examine in depth the qualitative and quantitative profile of the investigated preparations, which find until today wide applications in pharmaceutical and cosmetic industry, and to propose a validated method for their quality control. An HPLC-DAD-ESI-MS method was developed and optimised for the quantitative determination of the constituents. Marker constituents of Tiliae flos are the flavonoids, while the volatile content is also used for the quality control. However, the analyses of the non-volatile fraction gave complex chromatographic fingerprints containing simple phenolics and low molecular weight procyanidins. The use of different HPLC columns permitted a good separation of the constituents and enabled their quantitation, while HPLC-MS analyses permitted the detection of procyanidin oligomers. Overall, 31 constituents were detected and identified. Extensive preparative chromatographic investigations and 2D-NMR analyses allowed the characterisation of procyanidins as epicatechin derivatives. Finally, the HPLC method was validated and complied with ICH guidelines. This is the first report of detailed analysis of the chemical composition of Tiliae flos.

  2. HPLC evaluation of diclofenac in transdermal therapeutic preparations.

    Science.gov (United States)

    Klimes, J; Sochor, J; Dolezal, P; Körner, J

    2001-04-17

    High-performance liquid chromatography (HPLC) was selected for analytical evaluation of sodium diclofenac in original transdermal therapeutic preparations containing adjuvant substances (capsaicin, hyoscyamine). After isolation from laminated adhesive patches, diclofenac was analysed on columns with reversed phase, using the mobile phase ethanol and phosphate buffer (pH 6.5) with an addition of tetrabutylammonium iodide and detection at 284 nm. Not only the total amount of diclofenac in the patch was evaluated, but HPLC methodology was also employed to select a suitable acceptor medium for permeation experiments. In patches manufactured in the tested series, HPLC was also employed to examine the release of diclofenac and its in vitro permeation through the human skin.

  3. Preparative RP-HPLC purification and scale-up of crude orlistat%高纯度奥利司他的制备与放大

    Institute of Scientific and Technical Information of China (English)

    李小兵; 李思琦; 焦彦凯; 赵廷彬; 马双新; 解晓兰

    2014-01-01

    目的 对纯度98.0%左右(HPLC)的市场产品奥利司他进行分离纯化,制备纯度99.50%以上、单一杂质在0.10%以下的高纯度奥利司他.方法 采用反相制备高效液相色谱技术,选择C18填料,以甲醇-水(85:15,v/v)为流动相,收集的目标组分经浓缩、结晶得到高纯度的奥利司他.结果 小试和放大制备的奥利司他,纯度达99.50%以上、单一杂质控制在0.10%以下.放大制备了10kg以上的高纯产品,并解决了放大过程中配套设备和产品稳定性等实际问题.结论 常规分离技术难以去除的奥利司他原料药中的杂质,采用反相制备高效液相色谱技术可有效去除,此技术适合生产制备高质量高附加值的药物.

  4. [Preparation of ferulic acid, senkyunolide I and senkyunolide H from Ligusticum chuanxiong by preparative HPLC].

    Science.gov (United States)

    Xiong, Yao-Kun; Liang, Shuang; Hong, Yan-Long; Yang, Xiu-Juan; Shen, Lan; Du, Yan; Feng, Yi

    2013-06-01

    Preparative HPLC was used to prepare ferulic acid, senkyunolide I and senkyunolide H from Ligusticum chuanxiong. The separation was conducted on a Shim-Pack Prep-ODS (20.0 mm x 250 mm, 5 microm) column with the mobile phase of methanol-0.2% glacial acetic acid (50:50)at the flow rate of 5 mL x min(-1). The detection wavelength was 278 nm, and the purity of each compound was detected by HPLC analysis. Spectral data analyses including UV, ESI-MS and NMR were used to identify their structures. This method is simple, fast, which is suitable for preparation of standard reference of ferulic acid, senkyunolide I and senkyunolide H from L. chuanxiong and can meet the requirement of new drug research and development.

  5. Preparative chromatographic resolution of racemates using HPLC and SFC in a pharmaceutical discovery environment.

    Science.gov (United States)

    Miller, Larry; Potter, Matt

    2008-11-01

    The preparative chromatographic resolution of racemates has become a standard approach for the generation of enantiomers in pharmaceutical discovery laboratories. This paper will discuss the use of preparative HPLC and SFC to generate individual enantiomers for discovery activities. Analytical HPLC and SFC method development to rapidly screen chiral stationary phases and solvent combinations will be presented. The usefulness of preparative chromatographic resolution of racemates will be demonstrated through the presentation of numerous non-routine case studies from the laboratories at Amgen.

  6. Comparison of preparative HPLC/MS and preparative SFC techniques for the high-throughput purification of compound libraries.

    Science.gov (United States)

    Searle, Philip A; Glass, Keithney A; Hochlowski, Jill E

    2004-01-01

    A diverse set of 16 high-throughput organic synthesis libraries, consisting of 48 samples per library, has been purified by both preparative supercritical fluid chromatography (SFC) and preparative high-performance liquid chromatography (HPLC). This paper details the relative effectiveness of these two purification techniques in terms of success, yield, and purity of final product.

  7. Extraction and Purification of Glucoraphanin by Preparative High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Lee, Iris; Boyce, Mary C.

    2011-01-01

    A student activity that focuses on the isolation of glucoraphanin from broccoli using preparative high-performance liquid chromatography (HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts are known to possess anticancer properties. It is present naturally at high levels in broccoli and other "Brassica" vegetables. This…

  8. Extraction and Purification of Glucoraphanin by Preparative High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Lee, Iris; Boyce, Mary C.

    2011-01-01

    A student activity that focuses on the isolation of glucoraphanin from broccoli using preparative high-performance liquid chromatography (HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts are known to possess anticancer properties. It is present naturally at high levels in broccoli and other "Brassica" vegetables. This…

  9. Determination of active substances in multicomponent veterinary preparations of antiparasitic action by HPLC method.

    Science.gov (United States)

    Białecka, Wanda; Kulik, Anna

    2010-01-01

    The study aimed at the development of an HPLC method enabling the identification and determination of the content of selected compounds occurring in multicomponent veterinary preparations used in parasitic diseases. The studied compounds included: pyrantel embonate, fenbendazole, praziquantel, epsiprantel and febantel. Using the developed HPLC method, a good separation of the above compounds was achieved. The regression analysis has shown linearity of the method in the required concentration range. The determination of the compounds mentioned and statistical evaluation of the results have demonstrated that the method is characterized by a good selectivity and high precision.

  10. PREPARATIVE ISOLATION AND PURIFICATION OF CHEMICAL CONSTITUENTS OF BELAMCANDA BY MPLC, HSCCC AND PREP-HPLC

    Science.gov (United States)

    Wang, Xiaohong; Liang, Yong; Peng, Cuilin; Xie, Huichun; Pan, Man; Zhang, Tianyou; Ito, Yoichiro

    2010-01-01

    Combined with medium-pressure liquid chromatography (MPLC) and preparative high-pressure liquid chromatography (Prep-HPLC), high-speed countercurrent chromatography (HSCCC) was successfully applied for separation and purification of isoflavonoids from the extract of belamcanda. HSCCC separation was performed on a two-phase solvent system composed of methyl tert-butyl ether -ethyl acetate - n-butyl alcohol – acetonitrile −0.1% aqueous trifluoroacetic acid at a volume radio of 1:2:1:1:5. Semi-purified peak fractions from HSCCC separation were further purified by Prep-HPLC. Nine well-separated fractions were analyzed by HPLC-UV absorption spectrometry to determine their purities and characterized with ESI-MSn. Except for peaksland VII (unknown) seven compounds were identified as apocynin (peak II), mangiferin (peak III), 7-O-methylmangiferin (peak IV), hispidulin (peak V), 3′-hydroxyltectoridin (peak VI), iristectorin B (peak VII), isoiridin (peak IX). PMID:21552369

  11. Separation of cordycepin from Cordyceps militaris fermentation supernatant using preparative HPLC and evaluation of its antibacterial activity as an NAD(+)-dependent DNA ligase inhibitor.

    Science.gov (United States)

    Zhou, Xiaofeng; Cai, Guoqiang; He, Yi; Tong, Guotong

    2016-09-01

    Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and is a significant focus of research. However, the preparation of high-purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. In the present study, cordycepin was prepared by preparative high-performance liquid chromatography (prep-HPLC) and the purity obtained was 99.6%, indicating that this technique may be useful for the large-scale isolation of cordycepin in the future. The results of computational molecular docking analysis indicated that the interaction energy between cordycepin and NAD+-dependent DNA ligase (LigA) was lower than that between cordycepin and other common antibacterial targets. The highly pure cordycepin obtained by prep-HPLC demonstrated inhibitory activity against LigA from various bacteria in vitro. In conclusion, cordycepin may be useful as a broad-spectrum antibiotic targeting LigA in various bacteria.

  12. Chemical fingerprinting and quantitative analysis of a Panax notoginseng preparation using HPLC-UV and HPLC-MS

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    Shao Qing

    2011-02-01

    Full Text Available Abstract Background Xuesaitong (XST injection, consisting of total saponins from Panax notoginseng, was widely used for the treatment of cardio- and cerebro-vascular diseases in China. This study develops a simple and global quality evaluation method for the quality control of XST. Methods High performance liquid chromatography-ultraviolet detection (HPLC-UV was used to identify and quantify the chromatographic fingerprints of the XST injection. Characteristic common peaks were identified using HPLC with photo diode array detection/electrospray ionization tandem mass spectrometry (HPLC-PDA/ESI-MSn. Results Representative fingerprints from ten batches of samples showed 27 'common saponins' all of which were identified and quantified using ten reference saponins. Conclusion Chemical fingerprinting and quantitative analysis identified most of the common saponins for the quality control of P. notoginseng products such as the XST injection.

  13. Semi-preparative HPLC preparation and HPTLC quantification of tetrahydroamentoflavone as marker in Semecarpus anacardium and its polyherbal formulations.

    Science.gov (United States)

    Aravind, S G; Arimboor, Ranjith; Rangan, Meena; Madhavan, Soumya N; Arumughan, C

    2008-11-04

    Application of modern scientific knowledge coupled with sensitive analytical technique is important for the quality evaluation and standardization of polyherbal formulations. Semecarpus anacardium, an important medicinal plant with wide medicinal properties, is frequently used in a large number of traditional herbal preparations. Tetrahydroamentoflavone (THA), a major bioactive biflavonoid was selected as a chemical marker of S. anacardium and RP-semi-preparative HPLC conditions were optimized for the isolation of tetrahydroamentoflavone. HPTLC analytical method was developed for the fingerprinting of S. anacardium flavonoids and quantification of tetrahydroamentoflavone. The method was validated in terms of their linearity, LOD, LOQ, precision and accuracy and compared with RP-HPLC-DAD method. The methods were demonstrated for the chemical fingerprinting of S. anacardium plant parts and some commercial polyherbal formulations and the amount of tetrahydroamentoflavone was quantified. HPTLC analysis showed that S. anacardium seed contained approximately 10 g kg(-1) of tetrahydroamentoflavone. The methods were able to identify and quantify tetrahydroamentoflavone from complex mixtures of phytochemicals and could be extended to the marker-based standardization of polyherbal formulations, containing S. anacardium.

  14. HPLC analysis of oxindole alkaloids in Uncaria tomentosa: sample preparation and analysis optimisation by factorial design.

    Science.gov (United States)

    Bertol, Gustavo; Franco, Luzia; Oliveira, Brás Heleno de

    2012-01-01

    Uncaria tomentosa ("cat's claw") is widely used for the treatment of some infectious and inflammatory diseases. Oxindole alkaloids are regarded as the most important components responsible for the biological activities attributed to the plant. Their analysis require efficient sample preparation and suitable reference standards but few are commercially available. To develop and validate a HPLC analytical method for oxindole alkaloids in Uncaria tomentosa with emphasis on sample preparation. Factorial experimental designs were used for the optimisation of both sample preparation and chromatographic separation. The optimised sample preparation involved extraction with aqueous ethanol, and the granulometry of the powdered plant material significantly influenced extraction yields. Mitraphylline was used as a calibration reference for the determination of total alkaloids. The method was fully validated and showed good selectivity, linearity (r²  ≥ 0.9996), accuracy (≥ 96%) and precision (RSD < 2.4%). Detection and quantification limits for mitraphylline were 0.8 and 2.4 ppm, respectively. The optimised chromatographic method, using organic buffer in the mobile phase, provided baseline separation of tetracyclic and pentacyclic alkaloids in the samples. Calibration using mitraphylline provided more accurate estimates of total alkaloid content when compared to other available reference alkaloids. Copyright © 2011 John Wiley & Sons, Ltd.

  15. Novel HPLC Analysis of Hydrocortisone in Conventional and Controlled-Release Pharmaceutical Preparations

    Science.gov (United States)

    Oppong Bekoe, Samuel; Appiah, Enoch; Peprah, Paul

    2017-01-01

    An isocratic sensitive and precise reverse phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the determination and quantification of hydrocortisone in controlled-release and conventional (tablets and injections) pharmaceutical preparations. Chromatographic separation was achieved on an ODS (C18), 5 μm, 4.6 × 150 mm, with an isocratic elution using a freshly prepared mobile phase of composition methanol : water : acetic acid (60 : 30 : 10, v/v/v) at a flow rate of 1.0 ml/min. The detection of the drug was successfully achieved at a wavelength of 254 nm. The retention time obtained for the drug was 2.26 min. The proposed method produced linear detectable responses in the concentration range of 0.02 to 0.4 mg/ml of hydrocortisone. High recoveries of 98–101% were attained at concentration levels of 80%, 100%, and 120%. The intraday and interday precision (RSD) were 0.19–0.55% and 0.33–0.71%, respectively. A comparison of hydrocortisone analyses data from the developed method and the official USP method showed no significant difference (p > 0.05) at a 95% confidence interval. The method was successfully applied to the determination and quantification of hydrocortisone in six controlled-release and fifteen conventional release pharmaceutical preparations. PMID:28660092

  16. An automated on-line multidimensional HPLC system for protein and peptide mapping with integrated sample preparation

    NARCIS (Netherlands)

    Wagner, K.; Miliotis, T.; Marko-Varga, G; Bischoff, Rainer; Unger, K.K.

    2002-01-01

    A comprehensive on-line two-dimensional 2D-HPLC system with integrated sample preparation was developed for the analysis of proteins and peptides with a molecular weight below 20 kDa. The system setup provided fast separations and high resolving power and is considered to be a complementary techniqu

  17. A rapid and efficient preparation of [{sup 123}I]radiopharmaceuticals using a small HPLC Rocket[reg] column

    Energy Technology Data Exchange (ETDEWEB)

    Katsifis, Andrew [Radiopharmaceuticals Division R and D, Australian Nuclear Science and Technology, Organisation, Menai, NSW 2234, Sydney (Australia)]. E-mail: akx@ansto.gov.au; Papazian, Vahan [Radiopharmaceuticals Division R and D, Australian Nuclear Science and Technology, Organisation, Menai, NSW 2234, Sydney (Australia); Jackson, Timothy [Radiopharmaceuticals Division R and D, Australian Nuclear Science and Technology, Organisation, Menai, NSW 2234, Sydney (Australia); Loc' h, Christian [Radiopharmaceuticals Division R and D, Australian Nuclear Science and Technology, Organisation, Menai, NSW 2234, Sydney (Australia)

    2006-01-01

    A simplified method for the rapid and efficient preparation of [{sup 123}I]radiopharmaceuticals is described. Three radiopharmaceuticals, [{sup 123}I]{beta}-CIT, [{sup 123}I]MIBG and [{sup 123}I]clioquinol, were synthesised and purified as model compounds. The radiotracers were labelled with iodine-123 using electrophilic oxidative conditions and purified by a compact semi-preparative reverse phase column (C-18, 3 {mu}m, 7x53 mm, Alltima Rocket[reg, Alltech] using aqueous-ethanol as HPLC solvents that were directly used for radiopharmaceutical formulation. The radiochemical purity of the radioiodinated tracers as assessed by analytical HPLC was higher than 99% with specific activity higher than 3 GBq/nmol. The total preparation time of a radiotracer ranged from 40 to 60 min and, starting from 3.7 GBq of iodine-123, more than 2.5 GBq of formulated radiopharmaceuticals were available for clinical investigations.

  18. Comparison of preparative reversed phase liquid chromatography and countercurrent chromatography for the kilogram scale purification of crude spinetoram insecticide.

    Science.gov (United States)

    DeAmicis, Carl; Edwards, Neil A; Giles, Michael B; Harris, Guy H; Hewitson, Peter; Janaway, Lee; Ignatova, Svetlana

    2011-09-09

    Reversed phase HPLC (RP-HPLC) and high performance countercurrent chromatography (HPCCC) were compared for the pilot scale purification of two semi-synthetic spinosyns, spinetoram-J and spinetoram-L, the major components of the commercial insecticide spinetoram. Two, independently performed, 1 kg, purification campaigns were compared. Each method resulted in the isolation of both components at a purity of >97% and yields for spinetoram-J and spinetoram-L of >93% and ≥ 63% of theoretical, respectively. The HPCCC process produced a 2-fold higher throughput and consumed approximately 70% less solvent than preparative scale RP-HPLC, the volume of product containing fractions from HPCCC amounted to 7% of that produced by HPLC and so required much less post-run processing.

  19. Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jialian; Zhang, Yongqing, E-mail: fleiv@163.com [College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, Shandong (China); Lin, Yunliang; Wang, Xiao; Fang, Lei; Geng, Yanling [Shandong Analysis and Test Center, Shandong Academy of Sciences, Jinan, Shandong (China); Zhang, Qinde [Shandong College of Traditional Chinese Medicine, Laiyang, Shandong (China)

    2013-09-01

    Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC) combined with preparative HPLC (prep-HPLC). First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether-ethyl acetate-methanol-water (4:6:4:6, 4:6:5:5, v/v) was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further separated by prepHPLC, respectively, and another four bufadienolides were recovered. Their structures were confirmed by ESI-MS and {sup 1}H-NMR spectra. (author)

  20. Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

    Directory of Open Access Journals (Sweden)

    Jialian Li

    2013-01-01

    Full Text Available Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC combined with preparative HPLC (prep-HPLC. First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether - ethyl acetate - methanol - water (4:6:4:6, 4:6:5:5, v/v was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further separated by prep-HPLC, respectively, and another four bufadienolides were recovered. Their structures were confirmed by ESI-MS and ¹H-NMR spectra.

  1. Separation of cordycepin from Cordyceps militaris fermentation supernatant using preparative HPLC and evaluation of its antibacterial activity as an NAD+-dependent DNA ligase inhibitor

    Science.gov (United States)

    Zhou, Xiaofeng; Cai, Guoqiang; He, Yi; Tong, Guotong

    2016-01-01

    Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and is a significant focus of research. However, the preparation of high-purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. In the present study, cordycepin was prepared by preparative high-performance liquid chromatography (prep-HPLC) and the purity obtained was 99.6%, indicating that this technique may be useful for the large-scale isolation of cordycepin in the future. The results of computational molecular docking analysis indicated that the interaction energy between cordycepin and NAD+-dependent DNA ligase (LigA) was lower than that between cordycepin and other common antibacterial targets. The highly pure cordycepin obtained by prep-HPLC demonstrated inhibitory activity against LigA from various bacteria in vitro. In conclusion, cordycepin may be useful as a broad-spectrum antibiotic targeting LigA in various bacteria. PMID:27588098

  2. Preparative Isolation of Polar Antioxidant Constituents from Abies koreana Using Centrifugal Partition Chromatography Guided by DPPH center dot-HPLC Experiment

    NARCIS (Netherlands)

    Jeon, Je-Seung; Kim, Ji Hoon; Park, Chae Lee; Kim, Chul Young

    2015-01-01

    Preparative separation of antioxidant constituents from the leaves of Abies koreana Wilson (Pinaceae) was performed by centrifugal partition chromatography (CPC) with a two-phase solvent system of ethyl acetate-isopropanol-water (9:1:10, v/v) target-guided by DPPH•-HPLC experiment. In DPPH•-HPLC exp

  3. Chromatographic fingerprint analysis and simultaneous determination of eight lignans in Justicia procumbens and its compound preparation by HPLC-DAD.

    Science.gov (United States)

    Wang, Linan; Pan, Jianyu; Yang, Meihua; Wu, Jun; Yang, Junshan

    2011-03-01

    HPLC fingerprints were developed for the quality evaluation of Justicia procumbens and its compound preparation, Jian-er syrup, together with the simultaneous quantification of eight arylnaphthalide lignans (6'-hydroxy justicidin B, 6'-hydroxy justicidin A, 6'-hydroxy justicidin C, justicidin B, chinensinaphthol methyl ether, justicidin C, taiwanin C, and neojusticin A). Samples were separated with a Shiseido Capcell Pak C(18) reversed-phase column (250×4.6 mm id, 5 μm) using acetonitrile and water as the mobile phase. The column temperature was maintained at 35°C and the wavelength of detector was set at 256 nm. For fingerprint analysis, 17 peaks were selected as the characteristic peaks for the evaluation of the similarities among different J. procumbens samples collected in different places. The structures of lignans were confirmed by diagnostic fragments in the positive ESI-MS(n) . The new method was successfully applied for the chromatographic fingerprint analysis and simultaneous determination of eight lignans in its compound preparation, Jian-er syrup. All the results indicated that HPLC fingerprint assay in combination with multi-marker determination afforded a useful method for the quality control of J. procumbens and its compound preparation, Jian-er syrup.

  4. Enantioselective semi-preparative HPLC separation of PCB metabolites and their absolute structures determined by electronic and vibrational circular dichroism

    Energy Technology Data Exchange (ETDEWEB)

    Tuan, H.P.; Larsson, C.; Huehnerfuss, H. [Hamburg Univ. (Germany). Inst. fuer Organische Chemie; Hoffmann, F.; Froeba, M. [Giessen Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Bergmann, Aa. [Stockholm Univ. (Sweden). Dept. of Environmental Chemistry

    2004-09-15

    The present paper represents a first result of an ongoing systematic study of atropisomeric methylsulfonyl, methylthionyl, hydroxy, and methoxy metabolites of environmentally most relevant PCBs. This involves semi-preparative enantioselective HPLC separation to obtain pure atropisomers from synthesized PCB metabolite standards, their configuration estimation using the electronic circular dichroism (UV-CD) method and the determination / confirmation of these absolute configurations applying the combined vibrational circular dichroism (VCD) / ab initio approach. The following substances have been investigated: 4-HO-, 4-MeO-, 4-MeS-, 4-MeSO2-, 3-MeS- and 3-MeSO{sub 2}-CB149.

  5. DEVELOPMENT AND VALIDATION OF HPLC METHOD FOR SOME AZOLES IN PHARMACEUTICAL PREPARATION

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    Wael Abu Dayyih et al

    2012-10-01

    Full Text Available A new, simple and rapid reversed-phase high-performance liquid chromatography (HPLC method was developed and validated for the determination of some azoles drug (Ketoconazole, Isoconazole and Miconazole in pharmaceutical dosage forms in Jordan market. The HPLC separation was achieved on a C18 BDS column (100 mm × 4.6 mm using a mobile phase of acetonitrile and 0.05 M Ammonium Acetate buffer (70:30, v/v that adjusted to pH 6 using phosphoric acid at a flow rate of 1 mL min−1 and using UV absorbance detection at 254 nm. The method was validated for specificity, linearity, precision, accuracy, robustness. The separation was completed within 11.77 minutes and the assay was linear over the concentration range of 50% to 150% (r2 = 0.9999, the percent recovery for test and reference formulation was (98.14%-101.12%.

  6. Determination of umckalin in commercial tincture and phytopreparations containing Pelargonium sidoides by HPLC: comparison of sample preparation procedures.

    Science.gov (United States)

    Franco, L; de Oliveira, B H

    2010-06-15

    Roots of Pelargonium sidoides D.C. are used for the production of phytomedicines. Current quality control of phytopreparations containing P. sidoides extracts has been made in terms of total phenolics content. In this work we describe the development and validation of an HPLC method for the analysis of P. sidoides tincture and commercial syrup phytopreparations using umckalin (7-hydroxy-5,6-dimethoxycoumarin) as chemical marker. Two sample preparation procedures, liquid-liquid extraction (LLE) and solid-phase extraction (SPE) were also developed and compared. The samples were analyzed by RP-HPLC and the two methods were then validated and compared. The repeatability of the two procedures showed coefficients of variation (CV) of 1.2% for SPE procedure, and 1.3% for LLE. Recovery for both methods was higher than 95.2%. The linearity showed correlation coefficients better than 0.999 for both methods. The detection and quantification limit were 0.0098 and 0.0298microgmL(-1), respectively. The validated procedure was then used for the analysis of tincture and five batches of two commercial phytopreparations containing P. sidoides tincture.

  7. Sample preparation followed by HPLC under harmless 100% aqueous conditions for determination of oxytetracycline in milk and eggs.

    Science.gov (United States)

    Furusawa, Naoto

    2004-05-01

    A simple and hazardous chemical-free method for the high-performance liquid chromatographic determination of oxytetracycline (OTC) residues in milk and eggs has been developed. Sample preparation consists in homogenization with an aqueous solution by means of a handheld ultrasonic homogenizer followed by centrifugal ultrafiltration. HPLC is performed with an isocratic aqueous mobile phase and a photodiode array detector. Average recoveries of OTC (0.05, 0.1, and 0.2 microg mL(-1) for milk; 0.1, 0.2, and 0.4 microg mL(-1) for eggs) were > or =84% with relative standard deviations of < or =2.3%. The total time required for the analysis of one sample and LOQs were <30 min and <0.1 microg mL(-1), respectively. In all the processes, no organic solvents or hazardous reagents were used.

  8. Validated microbiological and HPLC methods for the determination of moxifloxacin in pharmaceutical preparations and human plasma

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    Ahmed A. Abdelaziz

    2012-12-01

    Full Text Available The article presents a comparison between microbiological and high performance liquid chromatographic (HPLC assays for quantification of moxifloxacin in tablets, ophthalmic solutions and human plasma. The microbiological method employed a cylinder-plate agar diffusion assay using a strain of Esherichia coli ATCC 25922 as the test organism and phosphate buffer (pH8 as the diluent. The calibration curves were linear (R²> 0.98 over a concentration range of 0.125 to 16 µgml-1. The within day and between days precisions were 0.999 over the range of 0.125 to 16 µg ml-1. The within day and between days precisions were < 4.07% and < 5.09% respectively. Recovery values were between 97.7 and 107.6%. Similar potencies were obtained after the analysis of moxifloxacin tablets and ophthalmic solutions by both methods. Also pharmacokinetic parameters were calculated after the analysis of plasma samples of six male healthhy volunteers by both validated methods.

  9. Stability-indicating HPLC method for the determination of the stability of oxytocin parenteral solutions prepared in polyolefin bags.

    Science.gov (United States)

    Kaushal, G; Sayre, B E; Prettyman, T

    2012-02-01

    Oxytocin is very commonly used in clinical settings and is a nonapeptide hormone that stimulates the contraction of uterine smooth muscles. In this study the stability of extemporaneously compounded oxytocin solutions was investigated in polyolefin bags. The sterile preparations of oxytocin were compounded to the strength of 0.02 U/mL in accordance with United States Pharmacopeia (USP) standards. In order to carry out the stability testing of these parenteral products, the solutions were stored under three different temperature conditions of -20°C (frozen), 2-6°C (refrigerated), and 22-25°C (room temperature). Three solutions from each temperature were withdrawn and were assessed for stability on days 0, 7, 15, 21, and 30 as per the USP guidelines. The assay of oxytocin was examined by an HPLC method at each time point. No precipitation, cloudiness or color change was observed during this study at all temperatures. The assay content by HPLC revealed that oxytocin retains greater than at least 90% of the initial concentrations for 21 days. There was no significant change in pH and absorbance values for 21 days under all the conditions of storage. Oxytocin parenteral solutions in the final concentration of 0.02 U/mL and diluted in normal saline are stable for at least 30 days under frozen and refrigerated conditions for 30 days. At the room temperature, the oxytocin solutions were stable for at least 21 days. The stability analysis results show that the shelf-life of 21 days observed in this study was far better than their recommended expiration dates.

  10. HPLC/DAD determination of rosmarinic acid in Salvia officinalis: sample preparation optimization by factorial design

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Karina B. de [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Farmacia; Oliveira, Bras H. de, E-mail: bho@ufpr.br [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica

    2013-01-15

    Sage (Salvia officinalis) contains high amounts of the biologically active rosmarinic acid (RA) and other polyphenolic compounds. RA is easily oxidized, and may undergo degradation during sample preparation for analysis. The objective of this work was to develop and validate an analytical procedure for determination of RA in sage, using factorial design of experiments for optimizing sample preparation. The statistically significant variables for improving RA extraction yield were determined initially and then used in the optimization step, using central composite design (CCD). The analytical method was then fully validated, and used for the analysis of commercial samples of sage. The optimized procedure involved extraction with aqueous methanol (40%) containing an antioxidant mixture (ascorbic acid and ethylenediaminetetraacetic acid (EDTA)), with sonication at 45 deg C for 20 min. The samples were then injected in a system containing a C{sub 18} column, using methanol (A) and 0.1% phosphoric acid in water (B) in step gradient mode (45A:55B, 0-5 min; 80A:20B, 5-10 min) with flow rate of 1.0 mL min-1 and detection at 330 nm. Using this conditions, RA concentrations were 50% higher when compared to extractions without antioxidants (98.94 {+-} 1.07% recovery). Auto-oxidation of RA during sample extraction was prevented by the use of antioxidants resulting in more reliable analytical results. The method was then used for the analysis of commercial samples of sage. (author)

  11. Comparison of two sample preparation procedures for HPLC determination of ochratoxin A

    Directory of Open Access Journals (Sweden)

    Vuković Gorica L.

    2009-01-01

    Full Text Available In preparation of samples for chromatographic determination of ochratoxin A, two types of columns were used for sample cleanup (SPE and immunoaffinity columns. The first method consisted of liquid-liquid extraction with a mixture of chloroform and phosphoric acid, followed by ion-exchange cleanup on Waters Oasis MAX columns. The sec­ond method consisted of extraction with a mixture of water and methanol, followed by LCTech OtaCLEAN immunoaf­finity column cleanup. Recoveries of the methods were determined at three levels in three repetitions for maize flour, and they were 84% (%RSD = 19.2 for the first method of sample preparation and 101% (%RSD = 2.2 for the second method. Values of LOQ for OTA were 0.25 and 1.00 μg/kg for the IAC and SPE clean-up procedures, respectively. Both methods comply with present regulations, but the MAX sample clean-up procedure should be used as an alternative, since the immunoaffinity column clean-up procedure is characterized by better reproducibility, accuracy, and efficiency.

  12. Comparison of alkylamide yield in ethanolic extracts prepared from fresh versus dry Echinacea purpurea utilizing HPLC-ESI-MS.

    Science.gov (United States)

    Spelman, Kevin; Wetschler, Matthew H; Cech, Nadja B

    2009-07-12

    Echinacea purpurea (L.) Moench, a top selling botanical medicine, is currently of considerable interest due to immunomodulatory, anti-inflammatory, antiviral and cannabinoid receptor 2 (CB2) binding activities of its alkylamide constituents. The purpose of these studies was to comprehensively profile the alkylamide (alkamide) content of E. purpurea root, and to compare yields of alkylamide constituents resulting from various ethanolic extraction procedures commonly employed by the dietary supplements industry. To accomplish this goal, a high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) method was validated for quantitative analysis of several E. purpurea alkylamides. Using this method, at least 15 alkylamides were identified and it was shown that fresh and dry E. purpurea extracts prepared from equivalent amounts (dry weight) of roots, with exceptions, exhibited similar yield of specific alkylamides. However, the amount of total dissolved solids in the dry extract was higher (by 38%) than the fresh extract. Two extracts prepared from dried roots at different ratios of root:solvent (1:5, w:v and 1:11, w:v) were similar in yield of total dissolved solids, but, there were differences in quantities of specific alkylamides extracted using these two root:solvent ratios. In addition, the important bioactive dodecatetraenoic acid isobutylamides are fully extracted from dry E. purpurea root in 2 days, suggesting that the manufacturing practice of macerating Echinacea extracts for weeks may be unnecessary for optimal alkylamide extraction. Finally, the identification of a new alkylamide has been proposed. These results demonstrate the differences of the described extractions and utility of the analytical methods used to determine the wide-ranging individual alkylamide content of commonly consumed Echinacea extracts.

  13. Goethite Bench-scale and Large-scale Preparation Tests

    Energy Technology Data Exchange (ETDEWEB)

    Josephson, Gary B.; Westsik, Joseph H.

    2011-10-23

    The Hanford Waste Treatment and Immobilization Plant (WTP) is the keystone for cleanup of high-level radioactive waste from our nation's nuclear defense program. The WTP will process high-level waste from the Hanford tanks and produce immobilized high-level waste glass for disposal at a national repository, low activity waste (LAW) glass, and liquid effluent from the vitrification off-gas scrubbers. The liquid effluent will be stabilized into a secondary waste form (e.g. grout-like material) and disposed on the Hanford site in the Integrated Disposal Facility (IDF) along with the low-activity waste glass. The major long-term environmental impact at Hanford results from technetium that volatilizes from the WTP melters and finally resides in the secondary waste. Laboratory studies have indicated that pertechnetate ({sup 99}TcO{sub 4}{sup -}) can be reduced and captured into a solid solution of {alpha}-FeOOH, goethite (Um 2010). Goethite is a stable mineral and can significantly retard the release of technetium to the environment from the IDF. The laboratory studies were conducted using reaction times of many days, which is typical of environmental subsurface reactions that were the genesis of this new process. This study was the first step in considering adaptation of the slow laboratory steps to a larger-scale and faster process that could be conducted either within the WTP or within the effluent treatment facility (ETF). Two levels of scale-up tests were conducted (25x and 400x). The largest scale-up produced slurries of Fe-rich precipitates that contained rhenium as a nonradioactive surrogate for {sup 99}Tc. The slurries were used in melter tests at Vitreous State Laboratory (VSL) to determine whether captured rhenium was less volatile in the vitrification process than rhenium in an unmodified feed. A critical step in the technetium immobilization process is to chemically reduce Tc(VII) in the pertechnetate (TcO{sub 4}{sup -}) to Tc(Iv)by reaction with the

  14. A rapid HPLC column switching method for sample preparation and determination of β-carotene in food supplements.

    Science.gov (United States)

    Brabcová, Ivana; Hlaváčková, Markéta; Satínský, Dalibor; Solich, Petr

    2013-11-15

    A simple and automated HPLC column-switching method with rapid sample pretreatment has been developed for quantitative determination of β-carotene in food supplements. Commercially samples of food supplements were dissolved in chloroform with help of saponification with 1M solution of sodium hydroxide in ultrasound bath. A 20-min sample dissolution/extraction step was necessary before chromatography analysis to transfer β-carotene from solid state of food supplements preparations (capsules,tablets) to chloroform solution. Sample volume - 3μL of chloroform phase was directly injected into the HPLC system. Next on-line sample clean-up was achieved on the pretreatment precolumn Chromolith Guard Cartridge RP-18e (Merck), 10×4.6mm, with a washing mobile phase (methanol:water, 92:8, (v/v)) at a flow rate of 1.5mL/min. Valve switch to analytical column was set at 2.5min in a back-flush mode. After column switching to the analytical column Ascentis Express C-18, 30×4.6mm, particle size 2.7μm (Sigma Aldrich), the separation and determination of β-carotene in food supplements was performed using a mobile phase consisting of 100% methanol, column temperature at 60°C and flow rate 1.5mL/min. The detector was set at 450nm. Under the optimum chromatographic conditions standard calibration curve was measured with good linearity - correlation coefficient for β-carotene (r(2)=0.999014; n=6) between the peak areas and concentration of β-carotene 20-200μg/mL. Accuracy of the method defined as a mean recovery was in the range 96.66-102.40%. The intraday method precision was satisfactory at three concentration levels 20, 125 and 200μg/mL and relative standard deviations were in the range 0.90-1.02%. The chromatography method has shown high sample throughput during column-switching pretreatment process and analysis in one step in short time (6min) of the whole chromatographic analysis.

  15. Simultaneous Determination of Eight Phenolic Acids, Five Saponins and Four Tanshinones for Quality Control of Compound Preparations Containing Danshen-Sanqi Herb-pair by HPLC-DAD.

    Science.gov (United States)

    Yao, Hong; Huang, Xiaomei; Li, Shaoguang; Wu, Youjia; Lin, Xinhua; Shi, Peiying

    2017-01-01

    The herb-pair, Salviaemiltiorrhizae (Danshen, DS) and Panaxnotoginseng (Sanqi,SQ), often occurs in traditional Chinese medicine prescriptions used for the treatment of cardiovascular diseases in clinics in Asian areas. Many commercial preparations containing the DS-SQ herb-pair were produced by various manufactures with the different production process. The raw materials were from different sources, which raised a challenge to control the quality of the herb-pair medicines. In this paper, a high-performance liquid chromatography (HPLC) method was developed to simultaneously determine seventeen bioactive components, including 8 phenolic acids, 4 tanshinones, and 5 saponins, for quality control of compound preparations containing DS-SQ herb-pair. The chromatographic separation was studied on an Ultimate™ XB-C18 column (150 mm × 4.6 mmi.d., 3.5 μm) with a mobile phase composed of 0.5% aqueous acetic acid and acetonitrile using a gradient elution in 70 min. The optimum detection wavelength was set at 288 nm for phenolic acids and tanshinones, and 203 nm for saponins. The method was validated sufficiently by examining the precision, recoveries, linearity, range, LOD and LOQ, and was successfully applied to quantify the seventeen compounds in five commercial preparations containing DS-SQ herb-pair. It is the first time to report the rapid and simultaneous analysis of the seventeen compounds with the base-line separation of peaks for ginsenoside Rg1 and Re in 70 min by routine HPLC. This HPLC method could be considered as good quality criteria to control the quality of preparations containing DS-SQ herb-pair. An HPLC method was originally developed to simultaneously quantify 8 phenolic acids, 4 tanshinones and 5 saponins in DS-SQ herb-pair preparations.The rapid and simultaneous analysis of the 17 compounds with the base-line separation of peaks for ginsenoside Rg1 and Re within 70 min was achieved for the first time by routine HPLC.The presented method was

  16. Simultaneous Determination of Eight Phenolic Acids, Five Saponins and Four Tanshinones for Quality Control of Compound Preparations Containing Danshen-Sanqi Herb-pair by HPLC-DAD

    Science.gov (United States)

    Yao, Hong; Huang, Xiaomei; Li, Shaoguang; Wu, Youjia; Lin, Xinhua; Shi, Peiying

    2017-01-01

    Background: The herb-pair, Salviaemiltiorrhizae (Danshen, DS) and Panaxnotoginseng (Sanqi,SQ), often occurs in traditional Chinese medicine prescriptions used for the treatment of cardiovascular diseases in clinics in Asian areas. Many commercial preparations containing the DS-SQ herb-pair were produced by various manufactures with the different production process. The raw materials were from different sources, which raised a challenge to control the quality of the herb-pair medicines. Objective: In this paper, a high-performance liquid chromatography (HPLC) method was developed to simultaneously determine seventeen bioactive components, including 8 phenolic acids, 4 tanshinones, and 5 saponins, for quality control of compound preparations containing DS-SQ herb-pair. The chromatographic separation was studied on an Ultimate™ XB-C18 column (150 mm × 4.6 mmi.d., 3.5 μm) with a mobile phase composed of 0.5% aqueous acetic acid and acetonitrile using a gradient elution in 70 min. Results: The optimum detection wavelength was set at 288 nm for phenolic acids and tanshinones, and 203 nm for saponins. The method was validated sufficiently by examining the precision, recoveries, linearity, range, LOD and LOQ, and was successfully applied to quantify the seventeen compounds in five commercial preparations containing DS-SQ herb-pair. Conclusions: It is the first time to report the rapid and simultaneous analysis of the seventeen compounds with the base-line separation of peaks for ginsenoside Rg1 and Re in 70 min by routine HPLC. This HPLC method could be considered as good quality criteria to control the quality of preparations containing DS-SQ herb-pair. SUMMARY An HPLC method was originally developed to simultaneously quantify 8 phenolic acids, 4 tanshinones and 5 saponins in DS-SQ herb-pair preparations.The rapid and simultaneous analysis of the 17 compounds with the base-line separation of peaks for ginsenoside Rg1 and Re within 70 min was achieved for the first

  17. Semi-preparative HPLC purification of δ-tocotrienol (δ-T3) from Elaeis guineensis Jacq. and Bixa orellana L. and evaluation of its in vitro anticancer activity in human A375 melanoma cells.

    Science.gov (United States)

    Beretta, Giangiacomo; Gelmini, Fabrizio; Fontana, Fabrizio; Moretti, Roberta Manuela; Montagnani Marelli, Marina; Limonta, Patrizia

    2017-04-24

    In this work, we report a rapid and convenient HPLC-UV-DAD method for the isolation of δ-T3 on semi-preparative scale from two different vitamin E rich processed, commercially available products obtained from the fruits of Elaeis guineensis Jacq. (oil palm) and from the seeds of Bixa orellana L. (achiote tree). Chromatography was run using reverse phase (RP) C-18 columns and HPLC-grade acetonitrile as mobile phase. The purity of the isolated δ-T3, assessed by GC-MS and (1)H NMR was above 98%. The δ-T3 cytotoxic activity found in vitro against the proliferation of human A375 melanoma cells compared to that of the other δ-T3 free tocols mixture suggest its primary role in the experimental anticancer activity observed for palm oil derived products. Taken altogether, the results of this study highlight the importance of the application of suitable purification systems for the preparations of tocotrienols prior to their experimental or clinical testing.

  18. Preparation and Characterization of a Polymeric Monolithic Column for Use in High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Bindis, Michael P.; Bretz, Stacey Lowery; Danielson, Neil D.

    2011-01-01

    The high-performance liquid chromatography (HPLC) experiment, most often done in the undergraduate analytical instrumentation laboratory course, generally illustrates reversed-phase chromatography using a commercial C[subscript]18 silica column. To avoid the expense of periodic column replacement and introduce a choice of columns with different…

  19. Preparation and Characterization of a Polymeric Monolithic Column for Use in High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Bindis, Michael P.; Bretz, Stacey Lowery; Danielson, Neil D.

    2011-01-01

    The high-performance liquid chromatography (HPLC) experiment, most often done in the undergraduate analytical instrumentation laboratory course, generally illustrates reversed-phase chromatography using a commercial C[subscript]18 silica column. To avoid the expense of periodic column replacement and introduce a choice of columns with different…

  20. HPLC Fingerprint with Multi-components Analysis for Quality Consistency Evaluation of Traditional Chinese Medicine Si-Mo-Tang Oral Liquid Preparation

    Institute of Scientific and Technical Information of China (English)

    YI Yue-neng; CHENG Xue-mei; LIU Ling-an; HU Gao-yun; CAI Guang-xian; DENG Yi-de; HUANG Ke-long; WANG Chang-hong

    2011-01-01

    Si-Mo-Tang(SMT) oral liquid preparation,a traditional Chinese medicine,was prepared from four crude herbal drugs,Fructus Aurantii Submaturus,Radix Aucklandiae,Semen Arecae and Radix Linderae Aggregatae.A combinative method using HPLC fingerprint and quantitative analysis was developed and validated for quality consistency evaluation of SMT.Individual HPLC chromatograms were evaluated against the mean chromatogram generated via a similarity evaluation computer program.Data from chromatographic fingerprints were also processed with principal component analysis(PCA) and hierarchical cluster analysis(HCA).Additionally,six components (naringin,isonaringin,hesperidin,neohesperidin,norisoboldine and potassium sorbate) in SMT were simultaneously determined to interpret the quality consistency.For fingerprint analysis,20 peaks were selected as the characteristic peaks to evaluate the similarities of 26 SMT collected from different manufacturers.Among the 20 characteristic peaks,10 peaks were assigned to be naringin,hesperidin,neohesperidin,isonaringin,neoeriocitrin,tangeretin,nobiletin,norisoboldine,5-(ethoxymethyl)furan-2-carbaldehyde and potassium sorbate,respectively.The results of similarity analysis,PCA and HCA,indicate that the samples from different manufacturers were consistent with each other in composition.The results from the quantitative data show that the contents of six compounds were significantly different in SMT oral liquid preparations from different manufacturers.The combinative method of chromatographic fingerprint with quantitative analysis developed here offered an efficient way for the quality consistency evaluation of the traditional Chinese medicine SMT.

  1. Preparation and characterization of a laboratory scale selenomethionine-enriched bread. Selenium bioaccessibility.

    Science.gov (United States)

    Sánchez-Martínez, María; Pérez-Corona, Teresa; Caímara, Carmen; Madrid, Yolanda

    2015-01-14

    This study focuses on the preparation at lab scale of selenomethionine-enriched white and wholemeal bread. Selenium was supplemented either by adding selenite directly to the dough or by using lab-made selenium-enriched yeast. The best results were obtained when using fresh selenium-enriched yeast. The optimum incubation time for selenomethionine-enriched yeast preparation, while keeping formation of selenium byproducts to a minimum, was 96 h. Selenium content measured by isotope dilution analysis (IDA)-ICP-MS in Se-white and Se-wholemeal bread was 1.28 ± 0.02 μg g–1 and 1.16 ± 0.02 μg g–1 (expressed as mean ± SE, 3 replicates), respectively. HPLC postcolumn IDA-ICP-MS measurements revealed that selenomethionine was the main Se species found in Se-enriched bread, which accounted for ca. 80% of total selenium. In vitro gastrointestinal digestion assay provided selenium bioaccessibility values of 100 ± 3% and 40 ± 1% for white and wholemeal Se-enriched bread, respectively, being selenomethionine the main bioaccessible Se species in white bread, while in wholemeal bread this compound was undetectable.

  2. Validated HPLC method for simultaneous estimation of khellol glucoside, khellin and visnagin in Ammi visnaga L. fruits and pharmaceutical preparations.

    Science.gov (United States)

    Badr, Jihan M; Hadad, Ghada M; Nahriry, Khaled; Hassanean, Hashem A

    2015-01-01

    Tea bags including fruits of Ammi visnaga L. are used in Egypt as remedy for the treatment of kidney stones. Our study focuses on developing simple and rapid method utilising HPLC for quantitative estimation of khellol glucoside (KG), khellin (KH) and visnagin (VS) simultaneously. Their concentrations were determined in A. visnaga L. fruits at different developmental stages and in pharmaceutical formulations together with following up them during shelf life. Separation was accomplished using HPLC. Perfect resolution between KG, KH and VS was possible through using a mobile phase consisting of water:methanol:tetrahydrofuran (50:45:5, v/v/v). Peaks were detected at 245 nm. The suggested method for the determination of KG, KH and VS was successful in determining the analytes of interest without any interference of other compounds and matrix. All validation parameters were satisfactory and the procedure was relatively easy and fast as extracts are evaluated without previous steps of purification.

  3. Development of a Gradient HPLC Method for the Simultaneous Determination of Sotalol and Sorbate in Oral Liquid Preparations Using Solid Core Stationary Phase

    Directory of Open Access Journals (Sweden)

    Ludmila Matysova

    2015-01-01

    Full Text Available A selective and sensitive gradient HPLC-UV method for quantification of sotalol hydrochloride and potassium sorbate in five types of oral liquid preparations was developed and fully validated. The separation of an active substance sotalol hydrochloride, potassium sorbate (antimicrobial agent, and other substances (for taste and smell correction, etc. was performed using an Ascentis Express C18 (100 × 4.6 mm, particles 2.7 μm solid core HPLC column. Linear gradient elution mode with a flow rate of 1.3 mL min−1 was used, and the injection volume was 5 µL. The UV/Vis absorbance detector was set to a wavelength of 237 nm, and the column oven was conditioned at 25°C. A sodium dihydrogen phosphate dihydrate solution (pH 2.5; 17.7 mM was used as the mobile phase buffer. The total analysis time was 4.5 min (+2.5 min for reequilibration. The method was successfully employed in a stability evaluation of the developed formulations, which are now already being used in the therapy of arrhythmias in pediatric patients; the method is also suitable for general quality control, that is, not only just for extemporaneous preparations containing the mentioned substances.

  4. Validation of a RP-HPLC-DAD Method for Chamomile (Matricaria recutita Preparations and Assessment of the Marker, Apigenin-7-glucoside, Safety and Anti-Inflammatory Effect

    Directory of Open Access Journals (Sweden)

    Felipe Galeti Miguel

    2015-01-01

    Full Text Available Chamomile is a medicinal plant, which presents several biological effects, especially the anti-inflammatory effect. One of the compounds related to this effect is apigenin, a flavonoid that is mostly found in its glycosylated form, apigenin-7-glucoside (APG, in natural sources. However, the affectivity and safety of this glycoside have not been well explored for topical application. In this context, the aim of this work was to develop and validate a reversed-phase high-performance liquid chromatography (RP-HPLC-DAD method to quantify APG in chamomile preparations. Additionally, the safety and the anti-inflammatory potential of this flavonoid were verified. The RP-HPLC-DAD method was developed and validated with linearity at 24.0–36.0 μg/mL range (r=0.9994. Intra- and interday precision (RSD were 0.27–2.66% and accuracy was 98.27–101.21%. The validated method was applied in the analysis of chamomile flower heads, glycolic extract, and Kamillen cream, supporting the method application in the quality control of chamomile preparations. Furthermore, the APG safety was assessed by MTT cytotoxicity assay and mutagenic protocols and the anti-inflammatory activity was confirmed by a diminished TNF-α production showed by mice macrophages treated with APG following LPS treatment.

  5. Preparative separation and identification of derivatized beta-methylphenylalanine enantiomers by chiral SFC, HPLC and NMR for development of new peptide ligand mimetics in drug discovery.

    Science.gov (United States)

    Nogle, Lisa M; Mann, Charles W; Watts, William L; Zhang, Yingru

    2006-03-03

    A direct preparative purification of all four isomers of the unnatural amino acid beta-methylphenylalanine was achieved using supercritical fluid chromatography (SFC) with stacked-injection. Final purification of the Cbz-methyl ester derived isomers was performed on a Daicel Chiralpak AD-H column (20 mm x 250 mm), using 50:50 methanol/ethanol as the organic modifier and resulted in purification of over 3.4 g of material in 6.25 h with >90% total recovery. The absolute stereochemical assignment of the purified amino acids was determined through a combination of chiral HPLC, NMR and optical rotation studies. To our knowledge, this is the first reported preparative approach that has yielded all four compounds in a single chromatographic run.

  6. Cytotoxics compounded sterile preparation control by HPLC during a 16-month assessment in a French university hospital: importance of the mixing bags step.

    Science.gov (United States)

    Castagne, Vincent; Habert, Hélène; Abbara, Chadi; Rudant, Eric; Bonhomme-Faivre, Laurence

    2011-09-01

    The Centralized Chemotherapy Reconstitution Unit (CCRU) of Paul Brousse Hospital Pharmacy Department assessed the reliability of its Cytotoxics Compounded Sterile Products (CCSP) preparation method in order to improve its CCSP quality assurance system. Five cytotoxic drugs - gemcitabine, 5-fluorouracil, docetaxel, paclitaxel, and oxaliplatin - were assayed by high performance liquid chromatography (HPLC) to determine CCSP concentration. During the observation period, 23,892 CCSP were prepared. Overall, 12,964 preparations contained one of the five analyzed drugs; 7382 (56.9%) out of 12,964 CCSP were analyzed by HPLC; 646 (8.8%) out of 7382 concentrations were outside ± 20% of the prescribed dose; 544 (84.2%) out of 646 were post-administration results and could not be verified. Out of 102 (15.8%) pre-administration results that were re-tested after re-shaking, 94 (92.2%) were found to be acceptable upon re-testing, and 8 (7.8%) were confirmed to be unacceptable and needed to be re-compounded. The 8.8% of tested CCSP were outside ± 20% of the prescribed dose, but extrapolating the results on re-tested CCSP, we can say that our CCSP preparation is reliable with an estimation of only 0.7% of 7382 CCSP analyzed, confirmed as being ± 20% outside the prescribed dose. Nevertheless, this ± 20% magnitude of error should be reduced. Based on pre-administration results, the primary cause of concentration errors appeared to be insufficient mixing of the finished product. Most CCSP dosages occurred after it had been administered, the organization should, therefore, be improved to include testing all CCSP prior to administration. Pharmaceutical companies should endeavor to manufacture compounded injectible drugs in a 'ready to use' form and provide vehicles in accurate volumes in order to improve compounding precision.

  7. Preparing soft-bodied arthropods for arthropods for microscope examination: Armored Scales (Insects: Hemiptera: Diaspididae)

    Science.gov (United States)

    Proper identification of armored scales (Hemiptera: Diaspididae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare armored scales specimens on microscope slides for examination and identification. Steps ranging from collect...

  8. Study and development of reversed-phase HPLC systems for the determination of 2-imidazolines in the presence of preservatives in pharmaceutical preparations.

    Science.gov (United States)

    Antoniou, Constantinos G; Markopoulou, Catherine K; Kouskoura, Maria G; Koundourellis, John E

    2011-01-01

    Different HPLC chromatographic systems were investigated on a C18 ACE 5 pm, 150 x 4.6 mm id column for the determination of tymazoline, tramazoline, and antazoline, with either naphazoline or xylometazoline, in commercial preparations. For the development and optimization of the systems, a Response Surface Method (r=0.925-0.980) was used to illustrate the changes in k as a function of pH values and different salt concentrations. The simultaneous separation of 2-imidazolines was accomplished at 40 degrees C with 0.01 M ammonium acetate-methanol (50+50, v/v, pH 6.0) mobile phase at a flow rate of 1.2 mL/min. In order to deal with the usual coexistence of 2-imidazolines with benzethonium and benzalkonium chloride preservatives, it was necessary to use another chromatographic system, 0.01 M ammonium acetate-methanol (50+50, v/v) mobile phase on a cyano ACE 5 pm, 150 x 4.6 mm id column. As part of a more thorough theoretical investigation, a partial least-squares (PLS) technique was used for modeling the RP-HPLC retention data. The model was based on molecular structure descriptors of the analytes' X variables and on their retention time (Log K) Y. The goodness of fit was estimated by the PLS correlation coefficient (r2) and root mean square error of estimation values, which were 0.994 and 0.0479, respectively.

  9. Routine sample preparation and HPLC analysis for ascorbic acid (vitamin C) determination in wheat plants and Arabidopsis leaf tissues.

    Science.gov (United States)

    Szalai, Gabriella; Janda, T; Pál, Magda

    2014-06-01

    Plants have developed various mechanisms to protect themselves against oxidative stress. One of the most important non-enzymatic antioxidants is ascorbic acid. There is thus a need for a rapid, sensitive method for the analysis of the reduced and oxidised forms of ascorbic acid in crop plants. In this paper a simple, economic, selective, precise and stable HPLC method is presented for the detection of ascorbate in plant tissue. The sensitivity, the short retention time and the simple isocratic elution mean that the method is suitable for the routine quantification of ascorbate in a high daily sample number. The method has been found to be better than previously reported methods, because of the use of an economical, readily available mobile phase, UV detection and the lack of complicated extraction procedures. The method has been tested on Arabidopsis plants with different ascorbate levels and on wheat plants during Cd stress.

  10. Determination of flavonoids, phenolic acid and polyalcohol in Butea monosperma and Hedychium coronarium by semi-preparative HPLC Photo Diode Array (PDA Detector

    Directory of Open Access Journals (Sweden)

    Jignasu P. Mehta

    2014-12-01

    Full Text Available The semi preparative HPLC method with PDA Detector was proposed for the determination of one phenolic acid, three flavonoids and one polyalcohol from Butea monosperma and Hedychium coronarium in gradient elution system. The influence of composition of the mobile phase concentration of the mix modifier and temperature on the separation of gallic acid, quercetin, iso-butrin, butrin and eugenol for 90 min was studied. Two different gradient programmes were used to separate these components. The lower limit of quantification of phenolic acid, flavonoids and eugenol is 0.050–0.150 μg/mL and was determined by the least square method and a good correlation was obtained for all separated components.

  11. A rapid, one step preparation for measuring selected free plus SO2-bound wine carbonyls by HPLC-DAD/MS.

    Science.gov (United States)

    Han, Guomin; Wang, Hua; Webb, Michael R; Waterhouse, Andrew L

    2015-03-01

    Carbonyl compounds are produced during fermentation and chemical oxidation during wine making and aging, and they are important to wine flavor and color stability. Since wine also contains these compounds as α-hydroxysulfonates as a result of their reaction with sulfur dioxide, an alkaline pre-treatment requiring oxygen exclusion has been used to release these bound carbonyls for analysis. By modifying the method to hydrolyze the hydroxysulfonates with heating and acid in the presence of 2,4-dinitrophenylhydrazine (DNPH), the carbonyl compounds are simultaneously and quickly released and derivatized, resulting in a simpler and more rapid method. In addition, the method avoids air exclusion complications during hydrolysis by the addition of sulfur dioxide. The method was optimized for temperature, reaction time, and the concentrations of DNPH, sulfur dioxide and acid. The hydrazones were shown to be stable for 10 h, adequate time for chromatographic analysis by HPLC-DAD/MS. This method is demonstrated for 2-ketoglutaric acid, pyruvic acid, acetoin and acetaldehyde, wine carbonyls of very different reactivities, and it offers good specificity, high recovery and low limits of detection. This new rapid, simple method is demonstrated for the measurement of carbonyl compounds in a range of wines of different ages and grape varieties. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Sample Preparation and Extraction in Small Sample Volumes Suitable for Pediatric Clinical Studies: Challenges, Advances, and Experiences of a Bioanalytical HPLC-MS/MS Method Validation Using Enalapril and Enalaprilat

    Directory of Open Access Journals (Sweden)

    Bjoern B. Burckhardt

    2015-01-01

    Full Text Available In USA and Europe, medicines agencies force the development of child-appropriate medications and intend to increase the availability of information on the pediatric use. This asks for bioanalytical methods which are able to deal with small sample volumes as the trial-related blood lost is very restricted in children. Broadly used HPLC-MS/MS, being able to cope with small volumes, is susceptible to matrix effects. The latter restrains the precise drug quantification through, for example, causing signal suppression. Sophisticated sample preparation and purification utilizing solid-phase extraction was applied to reduce and control matrix effects. A scale-up from vacuum manifold to positive pressure manifold was conducted to meet the demands of high-throughput within a clinical setting. Faced challenges, advances, and experiences in solid-phase extraction are exemplarily presented on the basis of the bioanalytical method development and validation of low-volume samples (50 μL serum. Enalapril, enalaprilat, and benazepril served as sample drugs. The applied sample preparation and extraction successfully reduced the absolute and relative matrix effect to comply with international guidelines. Recoveries ranged from 77 to 104% for enalapril and from 93 to 118% for enalaprilat. The bioanalytical method comprising sample extraction by solid-phase extraction was fully validated according to FDA and EMA bioanalytical guidelines and was used in a Phase I study in 24 volunteers.

  13. Application of spectrophotometric, densitometric, and HPLC techniques as stability indicating methods for determination of Zaleplon in pharmaceutical preparations

    Science.gov (United States)

    Metwally, Fadia H.; Abdelkawy, M.; Abdelwahab, Nada S.

    2007-12-01

    Spectrophotometric, spectrodensitometric and HPLC are stability indicating methods described for determination of Zaleplon in pure and dosage forms. As Zaleplon is easily degradable, the proposed techniques in this manuscript are adopted for its determination in presence of its alkaline degradation product, namely N-[4-(3-cyano-pyrazolo[1,5a]pyridin-7-yl)-phenyl]- N-ethyl-acetamide. These approaches are successfully applied to quantify Zaleplon using the information included in the absorption spectra of appropriate solutions. The second derivative (D 2) spectrophotometric method, allows determination of Zaleplon without interference of its degradate at 235.2 nm using 0.01N HCl as a solvent with obedience to Beer's law over a concentration range of 1-10 μg ml -1 with mean percentage recovery 100.24 ± 0.86%. The first derivative of the ratio spectra ( 1DD) based on the simultaneous use of ( 1DD) and measurement at 241.8 nm using the same solvent and over the same concentration range as (D 2) spectrophotometric method, with mean percentage recovery 99.9 ± 1.07%. The spectrodensitometric analysis allows the separation and quantitation of Zaleplon from its degradate on silica gel plates using chloroform:acetone:ammonia solution (9:1:0.2 by volume) as a mobile phase. This method depends on quantitave densitometric evaluation of thin layer chromatogram of Zaleplon at 338 nm over a concentration range of 0.2-1 μg band -1, with mean percentage recovery 99.73 ± 1.35. Also a reversed-phase liquid chromatographic method using 5-C8 (22 cm × 4.6 mm i.d. 5 μm particle size) column was described and validated for quantitation of Zaleplon using acetonitrile:deionised water (35:65, v/v) as a mobile phase using Paracetamol as internal standard and a flow rate of 1.5 ml min -1 with UV detection of the effluent at 232 nm at ambient temperature over a concentration range of 2-20 μg ml -1 with mean percentage recovery 100.19 ± 1.15%. The insignificance difference of the proposed

  14. Simultaneous determination of five anthraquinones in a Chinese traditional preparation by RP-HPLC using an improved extraction procedure

    Institute of Scientific and Technical Information of China (English)

    Yan-bin Shi; Hui-li Li; Hai-qin Wang; Yan-biao Yang; Xiao-yun Zhang; Hui Wang; Zong-jie Zhu; Zhi-ye Zhang; Cheng-an Zhang

    2014-01-01

    OBJECTIVE:The stable quality of Chinese herbal medicines is a critical factor for their reliable clinical efficiency. An improved liquid-liquid extraction procedure and a liquid chromatographic method were developed to simultaneously analyze five anthraquinones (aloe-emodin, rhein, emodin, chrysophanol and physcion) in a Chinese traditional hospital preparation, Fuyankang mixture, in order to quantitatively control its quality in a more effective way. METHODS: A more economical and repeatable extraction procedure based on conventional liquid-liquid extraction technique was developed and used to extract ifve marker components in Fuyankang mixture. These anthraquinones were separated in less than 20 min on a C18 column with methanol and 0.1%phosphoric acid (88:12, v/v) as mobile phase. The method was validated for speciifcity, precision, spiked recovery and stability. RESULTS: Compared to conventional liquid-liquid extraction, the improved liquid-liquid extraction was found to be more effective for simultaneous extraction of anthraquinones from an aqueous Chinese herbal preparation, especially for hydrophobic compounds. The improved extraction method was successful y applied to determine the content of ifve marker components in Fuyankang mixture by the means of reverse phase high-performance liquid chromatography. CONCLUSION:The improved extraction procedure may be suitable for routine quality control of Fuyankang mixture and other traditional preparations at city-level hospitals in China.

  15. An Efficient Method for the Preparative Isolation and Purification of Flavonoid Glycosides and Caffeoylquinic Acid Derivatives from Leaves of Lonicera japonica Thunb. Using High Speed Counter-Current Chromatography (HSCCC and Prep-HPLC Guided by DPPH-HPLC Experiments

    Directory of Open Access Journals (Sweden)

    Daijie Wang

    2017-02-01

    Full Text Available In this work, the n-butanol extract from leaves of Lonicera japonica Thunb. (L. japonica was reacted with DPPH and subjected to a HPLC analysis for the guided screening antioxidants (DPPH-HPLC experiments. Then, nine antioxidants, including flavonoid glycosides and caffeoylquinic acid derivatives, were isolated and purified from leaves of L. japonica using high speed counter-current chromatography (HSCCC and prep-HPLC. The n-butanol extract was firstly isolated by HSCCC using methyl tert-butyl ether/n-butanol/acetonitrile/water (0.5% acetic acid (2:2:1:5, v/v, yielding five fractions F1, F2 (rhoifolin, F3 (luteoloside, F4 and F5 (collected from the column after the separation. The sub-fractions F1, F4 and F5 were successfully separated by prep-HPLC. Finally, nine compounds, including chlorogenic acid (1, lonicerin (2, rutin (3, rhoifolin (4, luteoloside (5, 3,4-Odicaffeoylquinic acid (6, hyperoside (7, 3,5-O-dicaffeoylquinic acid (8, and 4,5-O-dicaffeoylquinic acid (9 were obtained, respectively, with the purities over 94% as determined by HPLC. The structures were identified by electrospray ionization mass spectrometry (ESI-MS, 1H- and 13C-NMR. Antioxidant activities were tested, and the isolated compounds showed strong antioxidant activities.

  16. An automatic refolding apparatus for preparative-scale protein production.

    Directory of Open Access Journals (Sweden)

    Yanye Feng

    flexible strategy may provide a powerful tool for preparative scale protein production.

  17. Development and Validation of RP-HPLC Method for Simultaneous Estimation of Ramipril, Aspirin and Atorvastatin in Pharmaceutical Preparations

    Directory of Open Access Journals (Sweden)

    Rajesh Sharma

    2012-01-01

    Full Text Available A simple, sensitive, accurate and rapid reverse phase high performance liquid chromatographic method is developed for the simultaneous estimation of ramipril, aspirin and atorvastatin in pharmaceutical preparations. Chromatography was performed on a 25cm×4.6 mm i.d, 5µm particle, C18 column with Mixture of (A acetonitrile methanol (65:35 and (B 10 mM sodium dihydrogen phosphate monohydrate (NaH2PO4.H2O buffer and mixture of A:B (60:40 v/v adjusted to pH 3.0 with o-phosphoric acid (5%v/v was used as a mobile phase at a flow rate of 1.5 ml min-1. UV detection was performed at 230 nm. Total run time was less then 12 min; retention time for Ramipril, aspirin and Atorvastatin were 3.620, 4.920 min and 11.710 min respectively. The method was validated for accuracy, precision, linearity, specificity and sensitivity in accordance with ICH guidelines. Validation revealed that the method is specific, rapid, accurate, precise, reliable, and reproducible. Calibration plots were linear over the concentration ranges 05-50 µg mL-1 for Ramipril, 05-100 µgmL-1 for aspirin and 02-20 µg mL-1 for atorvastatin. Limits of detection were 0.014, 0.10 and 0.0095 ng mL-1 limits of quantification were 0.043, 0.329 and 0.029 ng mL-1 for ramipril aspirin and atorvastatin respectively. The high recovery and low coefficients of variation confirm the suitability of the method for simultaneous analysis of the all three drugs in the dosage forms. The validated method was successfully used for quantitative analysis of marketed pharmaceutical preparations.

  18. HPLC检测止咳中药制剂中的沙丁胺醇%Detection of Salbutamol in some Cough Preparations of Traditional Chinese Medicine by HPLC

    Institute of Scientific and Technical Information of China (English)

    程齐来; 李洪亮; 张道英

    2011-01-01

    Objective:To develop a quantification method for the detection of salbutamol, a cough medicine,adulterated illegally in some cough preparations of traditional Chinese medicine.Method:Salbutamol was detected by HPLC on an Agilent Eclipse XDB-C18 column(4.6 mm × 150 mm, 5 μm) with methanol-potassium dihydrogen phosphate ( adjust pH to 7.0 with phosphoric acid) (5:95 ) as a mobile phase.According to the detected compound retention time,compared with the reference substance,the chemical drug salbutamol that was adulterated illegally into TCM preparations could be identified.Result: The conditions developed in this study could entirely separate from the cough medicine salbutamol added into TCM preparations.Using this method to detect 20 kinds of preparations and compared with the corresponding standard substances, salbutamol was not detected in 20 kinds of samples.Conclusion :The method is selective,sensitive and can be used as an effective means to detect illegal TCM preparation.%目的:建立检测止咳中药制剂中非法掺入的化学止咳平喘药物沙丁胺醇方法.方法:选用Agilent C18(4.6 mm×150 mm,5 μm),以甲醇-磷酸二氢钾溶液(用磷酸调节pH 3.0)5:95为流动相.根据所检测到化合物的色谱保留时间,并与对照品比较,鉴别中药制剂中非法掺入的沙丁胺醇.结果:本实验建立的条件能够把中药制剂中添加的化学药物(沙丁胺醇)完全分离开来;对20个制剂样品用建立的分析技术进行了检测,经与相应的对照品比较,20个样品均未检测到沙丁胺醇.结论:该方法选择性强,灵敏度高,町作为中药制剂中非法加人掺入化学药物成分沙丁胺醇的有效检测手段.

  19. Preparation of polydopamine-coated magnetic nanoparticles for dispersive solid-phase extraction of water-soluble synthetic colorants in beverage samples with HPLC analysis.

    Science.gov (United States)

    Chai, Weibo; Wang, Huijuan; Zhang, Ying; Ding, Guosheng

    2016-01-01

    A facile and sensitive dispersive solid-phase extraction (D-SPE) method for the extraction and enrichment of four representative synthetic colorants prior to high performance liquid chromatography analysis was introduced. As highly efficient adsorbents, polydopamine-coated Fe3O4 nanoparticles (Fe3O4@PDA NPs) were prepared by a simple and green procedure. Several factors affecting the extraction efficiency, mainly including the polymerization time of dopamine, pH of the sample solution, the amount of adsorbent, extraction time and the desorption conditions, were systematically studied. Under the optimized conditions, the enrichment factors for the four colorants were both higher than 176. The limits of detection (LODs) for the established d-SPE-HPLC method were found to be 0.20-0.25μgL(-1), which were lower than most chromatographic methods previously reported for synthetic colorant analysis. When used for quantitative analysis, wide linearity ranges (1-500μgL(-1) for amaranth and Ponceau 4R, and 0.80-500μgL(-1) for sunset yellow and allure red) were achieved with good correlation (R(2)≥0.9995). The developed method was also successfully applied to the analysis of colorants in beverage samples with satisfactory results, demonstrating its reliability and feasibility in real sample analysis.

  20. Liquid Chromatographic-Chemometric Techniques for the Simultaneous HPLC Determination of Lansoprazole, Amoxicillin and Clarithromycin in Commercial Preparation.

    Science.gov (United States)

    Aktas, A Hakan; Saridag, Ayse Mine

    2017-09-01

    Two multivariate calibration-prediction techniques, principal component regression (PCR) and partial least-squares regression (PLSR) were applied to the chromatographic multicomponent analysis of the drug containing lansoprazole (LAN), clarithromycin (CLA) and amoxicillin (AMO). Optimum chromatographic separation of LAN, CLA and AMO with atorvastatin as the internal standard (IS) was obtained by using Xterra® RP18 column 5 μm 4.6 × 250 mm2, and 25 mM ammonium chloride buffer prepared ammonium chloride, acetonitrile and bidistilled water (45:45:10 v/v) as the mobile phase at flow rate 1.0 mL/min. The high pressure liquid chromatography data sets consisting of the ratios of analyte peak areas to the IS peak area were obtained by using diode array detector detection at five wavelengths (205, 210, 215, 220 and 225 nm). LC-chemometric calibration for LAN, CLA and AMO were separately constructed by using the relationship between the peak-area ratio and training sets for each analyte. A series of synthetic solutions containing different concentrations of LAN, CLA and AMO were used to check the prediction ability of the PCR and PLS. Both of the two-chemometric methods in this study can be satisfactorily used for the quantitative analysis and for dissolutions tests of multicomponent commercial drug. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. A Novel Route to Prepare Nanocomposites in Larger Scale

    Institute of Scientific and Technical Information of China (English)

    Wei WU; Lailong LUO; Guangwen CHU; Shengjun BAI; Haikui ZOU; Jianfeng CHEN

    2007-01-01

    A novel route to prepare nanocomposites was illustrated through preparing overbased calcium petroleum sulfonate lubricating oil detergent, where the rotating packed bed (RPB) was used as reactor in place of conventional reaction vessel. The results showed that the carbonation efficiency is improved, the raw materials consumption is reduced, and the dispersibilities, sizes and morphologies of nano-sized CaCO3 particles in overbased detergent are enhanced. It is deduced reasonably that this route can be extensively applied to nanocomposites preparation in appropriate conditions and would be a platform technology in this field.

  2. Preparing Students with Learning Disabilities for Large-Scale Writing Assessments

    Science.gov (United States)

    Olinghouse, Natalie G.; Colwell, Ryan P.

    2013-01-01

    This article provides recommendations for teachers to better prepare 3rd through 12th grade students with learning disabilities for large-scale writing assessments. The variation across large-scale writing assessments and the multiple needs of struggling writers indicate the need for test preparation to be embedded within a comprehensive,…

  3. Preparing soft-bodied arthropods for microscope examination: Soft Scales (Insecta: Hemiptera: Coccidae)

    Science.gov (United States)

    Proper identification of soft scales (Hemiptera:Coccidae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare soft scale specimens on microscope slides for examination and identification. Steps ranging from collection, speci...

  4. Preparation of vitamin E loaded nanocapsules by the nanoprecipitation method: from laboratory scale to large scale using a membrane contactor.

    Science.gov (United States)

    Khayata, N; Abdelwahed, W; Chehna, M F; Charcosset, C; Fessi, H

    2012-02-28

    Vitamin E or α-tocopherol is widely used as a strong antioxidant in many medical and cosmetic applications, but is rapidly degraded, because of its light, heat and oxygen sensitivity. In this study, we applied the nanoprecipitation method to prepare vitamin E-loaded nanocapsules, at laboratory-scale and pilot-scale. We scaled-up the preparation of nanocapsule with the membrane contactor technique. The effect of several formulation variables on the vitamin E-loaded nanocapsules properties (mean diameter, zeta potential, and drug entrapment efficiency) was investigated. The optimized formulation at laboratory-scale and pilot-scale lead to the preparation of vitamin E-loaded nanocapsules with mean diameter of 165 and 172 nm, respectively, and a high encapsulation efficiency (98% and 97%, respectively).

  5. Application of an efficient strategy based on liquid-liquid extraction, high-speed counter-current chromatography, and preparative HPLC for the rapid enrichment, separation, and purification of four anthraquinones from Rheum tanguticum.

    Science.gov (United States)

    Chen, Tao; Liu, Yongling; Zou, Denglang; Chen, Chen; You, Jinmao; Zhou, Guoying; Sun, Jing; Li, Yulin

    2014-01-01

    This study presents an efficient strategy based on liquid-liquid extraction, high-speed counter-current chromatography, and preparative HPLC for the rapid enrichment, separation, and purification of four anthraquinones from Rheum tanguticum. A new solvent system composed of petroleum ether/ethyl acetate/water (4:2:1, v/v/v) was developed for the liquid-liquid extraction of the crude extract from R. tanguticum. As a result, emodin, aloe-emodin, physcion, and chrysophanol were greatly enriched in the organic layer. In addition, an efficient method was successfully established to separate and purify the above anthraquinones by high-speed counter-current chromatography and preparative HPLC. This study supplies a new alternative method for the rapid enrichment, separation, and purification of emodin, aloe-emodin, physcione, and chrysophanol. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Development of an HPLC-UV Method for the Analysis of Drugs Used for Combined Hypertension Therapy in Pharmaceutical Preparations and Human Plasma

    Directory of Open Access Journals (Sweden)

    Serife Evrim Kepekci Tekkeli

    2013-01-01

    Full Text Available A simple, rapid, and selective HPLC-UV method was developed for the determination of antihypertensive drug substances: amlodipine besilat (AML, olmesartan medoxomil (OLM, valsartan (VAL, and hydrochlorothiazide (HCT in pharmaceuticals and plasma. These substances are mostly used as combinations. The combinations are found in various forms, especially in current pharmaceuticals as threesome components: OLM, AML, and HCT (combination I and AML, VAL, and HCT (combination II. The separation was achieved by using an RP-CN column, and acetonitrile-methanol-10 mmol orthophosphoric acid pH 2.5 (7 : 13 : 80, v/v/v was used as a mobile phase; the detector wavelength was set at 235 nm. The linear ranges were found as 0.1–18.5 μg/mL, 0.4–25.6 μg/mL, 0.3–15.5 μg/mL, and 0.3–22 μg/mL for AML, OLM, VAL, and HCT, respectively. In order to check the selectivity of the method for pharmaceutical preparations, forced degradation studies were carried out. According to the validation studies, the developed method was found to be reproducible and accurate as shown by RSD ≤6.1%, 5.7%, 6.9%, and 4.6% and relative mean error (RME ≤10.6%, 5.8%, 6.5%, and 6.8% for AML, OLM, VAL, and HCT, respectively. Consequently, the method was applied to the analysis of tablets and plasma of the patients using drugs including those substances.

  7. Development of an HPLC-UV Method for the Analysis of Drugs Used for Combined Hypertension Therapy in Pharmaceutical Preparations and Human Plasma.

    Science.gov (United States)

    Kepekci Tekkeli, Serife Evrim

    2013-01-01

    A simple, rapid, and selective HPLC-UV method was developed for the determination of antihypertensive drug substances: amlodipine besilat (AML), olmesartan medoxomil (OLM), valsartan (VAL), and hydrochlorothiazide (HCT) in pharmaceuticals and plasma. These substances are mostly used as combinations. The combinations are found in various forms, especially in current pharmaceuticals as threesome components: OLM, AML, and HCT (combination I) and AML, VAL, and HCT (combination II). The separation was achieved by using an RP-CN column, and acetonitrile-methanol-10 mmol orthophosphoric acid pH 2.5 (7 : 13 : 80, v/v/v) was used as a mobile phase; the detector wavelength was set at 235 nm. The linear ranges were found as 0.1-18.5  μ g/mL, 0.4-25.6  μ g/mL, 0.3-15.5  μ g/mL, and 0.3-22  μ g/mL for AML, OLM, VAL, and HCT, respectively. In order to check the selectivity of the method for pharmaceutical preparations, forced degradation studies were carried out. According to the validation studies, the developed method was found to be reproducible and accurate as shown by RSD ≤6.1%, 5.7%, 6.9%, and 4.6% and relative mean error (RME) ≤10.6%, 5.8%, 6.5%, and 6.8% for AML, OLM, VAL, and HCT, respectively. Consequently, the method was applied to the analysis of tablets and plasma of the patients using drugs including those substances.

  8. Preparing Attitude Scale to Define Students' Attitudes about Environment, Recycling, Plastic and Plastic Waste

    Science.gov (United States)

    Avan, Cagri; Aydinli, Bahattin; Bakar, Fatma; Alboga, Yunus

    2011-01-01

    The aim of this study is to introduce an attitude scale in order to define students? attitudes about environment, recycling, plastics, plastic waste. In this study, 80 attitude sentences according to 5-point Likert-type scale were prepared and applied to 492 students of 6th grade in the Kastamonu city center of Turkey. The scale consists of…

  9. Fast centrifugal partition chromatography as a preparative-scale separation technique for citrus flavones

    Science.gov (United States)

    Fast centrifugal partition chromatography (FCPC) is a preparative-scale separations methodology based on the principles of counter current chromatography. Separations by FCPC are typically achieved with higher recoveries and with lower solvent use compared to conventional column chromatography. HSCP...

  10. Simultaneous determination of eight phenolic acids, five saponins and four tanshinones for quality control of compound preparations containing Danshen-Sanqi herb-pair by HPLC-DAD

    Directory of Open Access Journals (Sweden)

    Hong Yao

    2017-01-01

    Abbreviations used: DS: Salviae miltiorrhizae; SQ: Panaxnotoginseng; HPLC: high-performance liquid chromatography; DAD: diode array detector; LOD: limit of detection; LOQ: limit of quantification; TCMs: Traditional Chinese medicines; GDDP: Guanxin Danshen dripping pills; FDDP: Fufang Danshen dripping pills; FDT: Fufang Danshen tablets; FDC: Fufang Danshen capsules; GP: Guanxin pills

  11. GC-FID and HPLC-DAD Methods for the Determination of Menadione Sodium Bisulphite Directly and by Converting Menadione Sodium Bisulphite to Menadione in Pharmaceutical Preparation.

    Science.gov (United States)

    Demirkaya-Miloglu, Fatma; Kadioglu, Yucel; Senol, Onur

    2014-01-01

    was performed in both direct analysis of MSB and analysis of MN by converting MSB to MN with sodium carbonate. GC-FID method was carried out on the HP-5 capillary column GC-FID and HPLC-DAD methods were developed for determination of menadione (MN) and menadione sodium bisulphite (MSB). By means of each method, quantitative analysis of MSB in commercial pharmaceutical using nitrogen gas. HPLC-DAD method was achieved on the reversed phase C8 column by using a mobile phase consisting methanol and water. The calibration curves of GC-FID and HPLC-DAD for both analytes were linear in the same concentration range (0.5-20 μg/mL). Both methods were validated in terms of precision, accuracy, recovery and limits of detection (LOD) and quantitation (LOQ). Although LOD values of HPLC-DAD method (0.010 μg/mL for MN and 0.005 μg/mL for MSB) is lower than obtained values with GC-FID method (0.04 μg/mL for MN and 0.06 μg/mL for MSB), both methods gave similar and favorable results in terms of precision and accuracy. The Student's t-test was applied to investigate the significant of the different between the results of MSB determination with direct analysis of MSB and analysis of MN by converting MSB to MN by means of GC-FID and HPLC-DAD method in dosage form.

  12. An Efficient Method for the Preparative Isolation and Purification of Flavonoids from Leaves of Crataegus pinnatifida by HSCCC and Pre-HPLC

    Directory of Open Access Journals (Sweden)

    Lei Wen

    2017-05-01

    Full Text Available In this work, flavonoid fraction from the leaves of Crataegus pinnatifida was separated into its seven main constituents using a combination of HSCCC coupled with pre-HPLC. In the first step, the total flavonoid extract was subjected to HSCCC with a two-solvent system of chloroform/methanol/water/n-butanol (4:3:2:1.5, v/v, yielding four pure compounds, namely (–-epicatechin (1, quercetin-3-O-(2,6-di-α-l-rhamnopyranosyl-β-d-galactopyranoside (2, 4′′-O-glucosylvitexin (3 and 2′′-O-rhamnosylvitexin (4 as well as a mixture of three further flavonoids. An extrusion mode was used to rapidly separate quercetin-3-O-(2,6-di-α-l-rhamnopyranosyl-β-d-galactopyranoside with a big KD-value. In the second step, the mixture that resulted from HSCCC was separated by pre-HPLC, resulting in three pure compounds including: vitexin (5, hyperoside (6 and isoquercitrin (7. The purities of the isolated compounds were established to be over 98%, as determined by HPLC. The structures of these seven flavonoids were elucidated by ESI-MS and NMR spectroscopic analyses.

  13. An Efficient Method for the Preparative Isolation and Purification of Flavonoids from Leaves of Crataegus pinnatifida by HSCCC and Pre-HPLC.

    Science.gov (United States)

    Wen, Lei; Lin, Yunliang; Lv, Ruimin; Yan, Huijiao; Yu, Jinqian; Zhao, Hengqiang; Wang, Xiao; Wang, Daijie

    2017-05-09

    In this work, flavonoid fraction from the leaves of Crataegus pinnatifida was separated into its seven main constituents using a combination of HSCCC coupled with pre-HPLC. In the first step, the total flavonoid extract was subjected to HSCCC with a two-solvent system of chloroform/methanol/water/n-butanol (4:3:2:1.5, v/v), yielding four pure compounds, namely (-)-epicatechin (1), quercetin-3-O-(2,6-di-α-l-rhamnopyranosyl)-β-d-galactopyranoside (2), 4''-O-glucosylvitexin (3) and 2''-O-rhamnosylvitexin (4) as well as a mixture of three further flavonoids. An extrusion mode was used to rapidly separate quercetin-3-O-(2,6-di-α-l-rhamnopyranosyl)-β-d-galactopyranoside with a big KD-value. In the second step, the mixture that resulted from HSCCC was separated by pre-HPLC, resulting in three pure compounds including: vitexin (5), hyperoside (6) and isoquercitrin (7). The purities of the isolated compounds were established to be over 98%, as determined by HPLC. The structures of these seven flavonoids were elucidated by ESI-MS and NMR spectroscopic analyses.

  14. Simultaneous Determination of 5 Flavonoids and 7 Saponins for Quality Control of Traditional Chinese Medicine Preparation Xinnaoshutong Capsule Using HPLC-VWD-ELSD

    Science.gov (United States)

    Li, Jin; Bai, Yang; Zhang, Peng; An, Mingrui; Hu, Li-min

    2017-01-01

    Xinnaoshutong capsule (XC) is a traditional Chinese prescription derived from the ripe fruit of Tribulus terrestris L. (TT). Although XC has long been considered as an important herbal medicine, no analytical method of marker compounds for quality assessment is registered in the Chinese Pharmacopoeia. A simple analytical method of twelve marker components was developed and validated by HPLC-VWD-ELSD method. Chromatographic separation by HPLC was carried out on a Hedera ODS 2 column (4.6 × 250 mm, 5 μm) by gradient elution with acetonitrile-water (0.1% formic acid) as the mobile phase. Various extraction conditions were optimized to achieve twelve marker compounds with faster extraction and higher recovery. The analytical condition was then validated in terms of the linearity, accuracy and precision, repeatability, and stability. The twelve markers were successfully quantified in 30 batches of commercial samples. The developed HPLC-VWD-ELSD could be used as a rapid and reliable way in the assessment and quality control of XC and TT. PMID:28191359

  15. Simultaneous Determination of 5 Flavonoids and 7 Saponins for Quality Control of Traditional Chinese Medicine Preparation Xinnaoshutong Capsule Using HPLC-VWD-ELSD

    Directory of Open Access Journals (Sweden)

    Jin Li

    2017-01-01

    Full Text Available Xinnaoshutong capsule (XC is a traditional Chinese prescription derived from the ripe fruit of Tribulus terrestris L. (TT. Although XC has long been considered as an important herbal medicine, no analytical method of marker compounds for quality assessment is registered in the Chinese Pharmacopoeia. A simple analytical method of twelve marker components was developed and validated by HPLC-VWD-ELSD method. Chromatographic separation by HPLC was carried out on a Hedera ODS 2 column (4.6 × 250 mm, 5 μm by gradient elution with acetonitrile-water (0.1% formic acid as the mobile phase. Various extraction conditions were optimized to achieve twelve marker compounds with faster extraction and higher recovery. The analytical condition was then validated in terms of the linearity, accuracy and precision, repeatability, and stability. The twelve markers were successfully quantified in 30 batches of commercial samples. The developed HPLC-VWD-ELSD could be used as a rapid and reliable way in the assessment and quality control of XC and TT.

  16. HPLC profiling of Phellinus linteus.

    Science.gov (United States)

    Kojima, Kazuo; Ogihara, Yukio; Sakai, Yoshimichi; Mizukami, Hajime; Nagatsu, Akito

    2008-10-01

    HPLC chromatograms of MeOH extracts from a fruit body of the wild-grown P. linteus (natural fruit body), from cultivated fungus (cultivated fruit body), and from the cultured mycelia were compared. The extract prepared from the natural fruit bodies revealed a typical HPLC profile referred to as type 1 with a major peak corresponding to meshimakobnol A (1) together with two minor peaks of hypholomine B (3) and inoscavin A (4); the cultivated fruit bodies exhibited a profile referred to as type 2 with major peaks corresponding to 3 and 4 and a minor peak of 1, and the cultured mycelia showed a profile referred to as type 3 without any of these peaks. We also analyzed HPLC chromatograms of commercial products of P. linteus obtained in the markets. Most of the products claimed to be natural fruit bodies exhibited type 1 profiles, except for one product having an intermediate HPLC profile between type 1 and type 2. The products claimed to be cultivated fruit bodies and cultured mycelia revealed type 2 and type 3 profiles, respectively. The present results indicate that the HPLC chromatogram of the methanol extract of P. linteus can be used as a fingerprint to identify whether the product is from natural fruit bodies, cultivated fruit bodies, or cultured mycelia.

  17. Evaluation of scale-up from analytical to preparative supercritical fluid chromatography.

    Science.gov (United States)

    Enmark, Martin; Åsberg, Dennis; Leek, Hanna; Öhlén, Kristina; Klarqvist, Magnus; Samuelsson, Jörgen; Fornstedt, Torgny

    2015-12-18

    An approach for reliable transfer from analytical to preparative scale supercritical fluid chromatography was evaluated. Here, we accounted for the conditions inside the columns as well as to the fact that most analytical instruments are volume-controlled while most preparative scale units are mass-controlled. The latter is a particular problem when performing pilot scale experiments and optimizations prior to scaling up to production scale. This was solved by measuring the mass flow, the pressure and the temperature on the analytical unit using external sensors. Thereafter, it was revealed with a design of experiments approach that the methanol fraction and the pressure are the two most important parameters to control for preserved retention throughout the scale-up; for preserved selectivity the temperature was most important in this particular system. Using this approach, the resulting chromatograms from the preparative unit agreed well with those from the analytical unit while keeping the same column length and particles size. A brief investigation on how the solute elution volume varies with the volumetric flow rate revealed a complex dependency on pressure, density and apparent methanol content. Since the methanol content is a parameter of great importance to control during the scale up, we must be careful when changing operational and column design conditions which generates deviations in pressure, density and methanol content between different columns. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Fishing and knockout of bioactive compounds using a combination of high-speed counter-current chromatography (HSCCC) and preparative HPLC for evaluating the holistic efficacy and interaction of the components of Herba Epimedii.

    Science.gov (United States)

    Jin, Jing; Li, Yubo; Kipletting Tanui, Emmanuel; Han, Liwen; Jia, Yuan; Zhang, Lu; Wang, Yuming; Zhang, Xiuxiu; Zhang, Yanjun

    2013-05-20

    Due to the complex chemical compositions and pharmacological effects of traditional Chinese medicines, we developed a strategy based on fishing and knockout of bioactive compounds using a combination of high-speed counter-current chromatography (HSCCC) and preparative HPLC for evaluating the holistic activity and interaction of the components of Herba Epimedii. First, osteoblast target cell extraction was used for preliminary screening of the potential bioactive compounds of Herba Epimedii. Second, the bioactive compounds identified (epimedin A, epimedin B, epimedin C and icariin) were fished and knocked out using high-speed counter-current chromatography and preparative HPLC. Third, the bioactivity of resulting fractions was assessed by determining their influence on cell proliferation and differentiation, thereby allowing for an evaluation of their interaction.The pharmacodynamic contribution ratio of each bioactive compound to the efficacy of the herbal medicine could then be comprehensively and intuitively determined based on the spectra-activity correlations (VIP values) of the tested compositions using partial least-squares regression (PLS-R), through which the reliability of the screening and isolation of bioactive compounds by the target cell extraction technique were verified. The proposed strategy is a useful approach with potential application in other traditional Chinese medicines.

  19. HPLC-MS/MS Analysis of Poly phenols in Different Fermented Type Tea Products Prepared from Camellia sinensis'Baiye Dancong'%白叶单枞不同发酵茶中多酚类成分的HPLC-MS/MS分析

    Institute of Scientific and Technical Information of China (English)

    苗爱清; 程悦; 梁祈; 赵超艺; 凌彩金; 庞式; 王冬梅

    2011-01-01

    Chemical compositions of broken black tea, oolong tea and dark tea prepared from Camellia sinensis ‘Baiye Dancong’ were analyzed by HPLC-MS/MS method.Comparing the UV absorption spectra and mass spectra of the peaks in the obtained HPLC chromatograms with those of the authentic standards and related literatures, 32, 30 and 14 compounds were identified from broken black tea, oolong tea and dark tea respectively.These compounds included catechins, alkaloids.Some non-catechin polyphenol compounds such as flavonol glycosides with kaempferol, quercetin and myricitin as aglycones, and catechin polymers such as theasinensins were also identified.%采用HPLC-MS/MS对以白叶单枞茶为原料生产的红碎茶、乌龙茶、黑茶进行分析,通过对紫外吸收光谱以及质谱信息进行分析,并参考相关文献,推定出白叶单枞红茶中32个化合物,乌龙茶中30个化合物,黑茶中14个化合物.这些化合物中包括常见的儿茶素类化合物、生物碱.此外还检测到多种以山奈酚、槲皮素、杨梅素为苷元的黄酮醇苷等非儿茶素类茶多酚和茶双没食子儿茶素等儿茶素聚合物.

  20. Conditions for sample preparation and quantitative HPLC/MS-MS analysis of bulky adducts to serum albumin with diolepoxides of polycyclic aromatic hydrocarbons as models.

    Science.gov (United States)

    Westberg, Emelie; Hedebrant, Ulla; Haglund, Johanna; Alsberg, Tomas; Eriksson, Johan; Seidel, Albrecht; Törnqvist, Margareta

    2014-02-01

    Stable adducts to serum albumin (SA) from electrophilic and genotoxic compounds/metabolites can be used as biomarkers for quantification of the corresponding in vivo dose. In the present study, conditions for specific analysis of stable adducts to SA formed from carcinogenic polycyclic aromatic hydrocarbons (PAH) were evaluated in order to achieve a sensitive and reproducible quantitative method. Bulky adducts from diolepoxides (DE) of PAH, primarily DE of benzo[a]pyrene (BPDE) and also DE of dibenzo[a,l]pyrene (DBPDE) and dibenzo[a,h]anthracene (DBADE), were used as model compounds. The alkylated peptides obtained after enzymatic hydrolysis of human SA modified with the different PAHDE were principally PAHDE-His-Pro, PAHDE-His-Pro-Tyr and PAHDE-Lys. Alkaline hydrolysis under optimised conditions gave the BPDE-His as the single analyte of alkylated His, but also indicated degradation of this adduct. It was not possible to obtain the BPDE-His as one analyte from BPDE-alkylated SA through modifications of the enzymatic hydrolysis. The BPDE-His adduct was shown to be stable during the weak acidic conditions used in the isolation of SA. Enrichment by HPLC or SPE, but not butanol extraction, gave good recovery, using Protein LoBind tubes. A simple internal standard (IS) approach using SA modified with other PAHDE as IS was shown to be applicable. A robust analytical procedure based on digestion with pronase, enrichment by HPLC or SPE, and analysis with HPLC/MS-MS electrospray ionisation was achieved. A good reproducibility (coefficient of variation (CV) 11 %) was obtained, and the achieved limit of detection for the studied PAHDE, using standard instrumentation, was approximately 1 fmol adduct/mg SA analysing extract from 5 mg SA.

  1. Preparation of MCM-41 in Industrial Scale and Its Application in Heavy Oil Processing

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A series of MCM-41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM-41 product have been studied by using X-ray diffraction(XRD), thermogravimetric(TG) and electron microscopy (TEM). It is shown that the pH values have a significant effect on the crystallinity of the synthesized product. Under proper conditions, the MCM-41 prepared on an industrial scale has the same performance as the samples prepared on an Lab-scale. The prepared MCM-41 was used as a modifier of zeolite Y for fluid catalytic cracking (FCC) of residual oil. It is shown that the addition of the MCM-41 in the zeolite Y catalyst increases the pore size, and surface area of the catalysts, which helps to increase the yield of gasoline and diesel and decrease the production of gaseous product and carbon deposition in the catalyst. The better performance of the MCM-41 modified zeolite Y catalyst is believed to be due to its adjustment on the acidity and increase of the pore size.

  2. Preparative isolation and purification of seven main antioxidants from Eucommia ulmoides Oliv. (Du-zhong) leaves using HSCCC guided by DPPH-HPLC experiment.

    Science.gov (United States)

    Dai, Xingping; Huang, Qiong; Zhou, Boting; Gong, Zhicheng; Liu, Zhaoqian; Shi, Shuyun

    2013-08-15

    Seven antioxidants were purified from Eucommia ulmoides Oliv. leaves using HSCCC guided by DPPH-HPLC experiment. HSCCC was successfully used to separate target antioxidants by three runs with different solvent systems after D101 column chromatography fractionation. Ethyl acetate-n-butanol-water (1:2:3, v/v/v) was selected as the optimum solvent system to purify geniposidic acid. Ethyl acetate-ethanol-water (4:1:5, v/v/v) was used to isolate caffeic acid, chlorogenic acid and ferulic acid. While three flavonoids, quercetin-3-O-sambubioside, rutin and isoquercitrin were purified by petroleum ether-ethyl acetate-methanol-water (1:5:1:5, v/v/v/v). The structures were identified by MS and NMR. Antioxidant activities were assessed, and compounds 2-7 showed strong antioxidant activities. This is the first report about separation of antioxidants from E. ulmoides leaves by HSCCC. The results indicated that the combinative methods using DPPH-HPLC and HSCCC could be widely applied for screening and isolation of antioxidants from complex extracts. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Preparing Attitude Scale to Define Students‟ Attitudes about Environment, Recycling, Plastic andPlastic Waste

    Directory of Open Access Journals (Sweden)

    Cagri AVAN

    2011-01-01

    Full Text Available The aim of this study is to introduce an attitude scale in order to define students‟ attitudes about environment, recycling, plastics, plastic waste. In this study, 80 attitude sentences according to 5-point Likert-type scale were prepared and applied to 492 students of 6th grade in the Kastamonu city center of Turkey. The scale consists of cognitive, affective, and psychomotor skills domains. After the factor analysis it was found that they have 3, 4 and 5 factors accordingly. After the reliability analysis the alpha values for cognitive, affective and psychomotor scales are .854, .871 and .826 respectively. As a result, it is found that the scale can be used to define cognitive, affective and psychomotor attitudes.

  4. Preparation of liposomes: a novel application of microengineered membranes--from laboratory scale to large scale.

    Science.gov (United States)

    Laouini, A; Charcosset, C; Fessi, H; Holdich, R G; Vladisavljević, G T

    2013-12-01

    A novel ethanol injection method using microengineered nickel membrane was employed to produce POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) and Lipoid(®) E80 liposomes at different production scales. A stirred cell device was used to produce 73ml of the liposomal suspension and the product volume was then increased by a factor of 8 at the same transmembrane flux (140lm(-2)h(-1)), volume ratio of the aqueous to organic phase (4.5) and peak shear stress on the membrane surface (2.7Pa). Two different strategies for shear control on the membrane surface have been used in the scaled-up versions of the process: a cross flow recirculation of the aqueous phase across the membrane surface and low frequency oscillation of the membrane surface (∼40Hz) in a direction normal to the flow of the injected organic phase. Using the same membrane with a pore size of 5μm and pore spacing of 200μm in all devices, the size of the POPC liposomes produced in all three membrane systems was highly consistent (80-86nm) and the coefficient of variation ranged between 26 and 36%. The smallest and most uniform liposomal nanoparticles were produced in a novel oscillating membrane system. The mean vesicle size increased with increasing the pore size of the membrane and the injection time. An increase in the vesicle size over time was caused by deposition of newly formed phospholipid fragments onto the surface of the vesicles already formed in the suspension and this increase was most pronounced for the cross flow system, due to long recirculation time. The final vesicle size in all membrane systems was suitable for their use as drug carriers in pharmaceutical formulations.

  5. 1H NMR-based metabolomics combined with HPLC-PDA-MS-SPE-NMR for investigation of standardized Ginkgo biloba preparations

    OpenAIRE

    Agnolet, Sara; Jaroszewski, Jerzy W.; Verpoorte, Robert; Staerk, Dan

    2010-01-01

    Commercial preparations of Ginkgo biloba are very complex mixtures prepared from raw leaf extracts by a series of extraction and prepurification steps. The pharmacological activity is attributed to a number of flavonoid glycosides and unique terpene trilactones (TTLs), with largely uncharacterized pharmacological profiles on targets involved in neurological disorders. It is therefore important to complement existing targeted analytical methods for analysis of Ginkgo biloba preparations with a...

  6. Preparation, characterization and scale-up of sesamol loaded solid lipid nanoparticles

    Directory of Open Access Journals (Sweden)

    Vandita Kakkar

    2012-01-01

    Full Text Available Sesamol loaded solid lipid nanoparticles (SSLNs were prepared with the aim of minimizing its distribution to tissues and achieving its targeting to the brain. Three scale-up batches (100x1 L of S-SLNs were prepared using a microemulsification technique and all parameters were statistically compared with the small batch (1x;10 mL. S-SLNs with a particle size of less than 106 nm with a spherical shape (transmission electron microscopy were successfully prepared with a total drug content and entrapment efficiency of 94.26±2.71% and 72.57±5.20%, respectively. Differential scanning calorimetry and infrared spectroscopy confirmed the formation of lipidic nanoparticles while powder X-ray diffraction revealed their amorphous profile. S-SLNs were found to be stable for three months at 5±3°C in accordance with International Conference on Harmonisation guidelines. The SLN preparation process was successfully scaled-up to a 100x batch on a laboratory scale. The procedure was easy to perform and allowed reproducible SLN dispersions to be obtained.

  7. Application of a microplate scale fluorochrome staining assay for the assessment of viability of probiotic preparations.

    Science.gov (United States)

    Alakomi, H-L; Mättö, J; Virkajärvi, I; Saarela, M

    2005-07-01

    Cell viability in probiotic preparations is traditionally assessed by the plate count technique. Additionally, fluorescent staining combined with epifluorescence microscopy or flow cytometry has been developed for the viability assessment, but the currently available assays are either laborious or require highly sophisticated equipment. The aim of this study was to investigate the applicability of a microplate scale fluorochrome assay for predicting the cell state of freeze-dried Lactobacillus rhamnosus and Bifidobacterium animalis subsp. lactis preparations. In addition to viability assessment with LIVE/DEAD BacLight Bacterial Viability Kit, DiBAC(4)3 stain was used for the kinetic measurement of changes in bifidobacterial cell membrane functions during exposure to low pH. The microplate scale fluorochrome assay results on the viability and cell numbers of probiotic preparations correlated well with the results obtained with the culture-based technique and (with few exceptions) with epifluorescence microscopy. The assay was applicable also for the viability assessment of stressed (acid-treated) cells provided that the cell density in treatments was adjusted to the optimal measurement level of the fluorometer. The microplate scale fluorochrome assay offers a rapid and robust tool for the viability assessment of probiotic preparations, and enables also kinetic measurements.

  8. Preparation of a novel ionic hybrid stationary phase by non-covalent functionalization of single-walled carbon nanotubes with amino-derivatized silica gel for fast HPLC separation of aromatic compounds.

    Science.gov (United States)

    Aral, Hayriye; Çelik, K Serdar; Aral, Tarık; Topal, Giray

    2016-03-01

    Single-walled carbon nanotubes (SWCNTs) were immobilized on spherical silica gel with a 4-μm average particle size and a 60-Å average pore size. The amino-derivatized silica gel was non-covalently coated with carboxylated SWCNTs to preserve the structure of the nanotubes and their physico-chemical properties. The novel ionic hybrid stationary phase was characterized by scanning electron microscopy (SEM), infra-red (IR) spectroscopy and elemental analysis, and then, it was used to fill an empty 150×4.6mm(2) high-performance liquid chromatography (HPLC) column. Chromatographic parameters, such as the theoretical plate number, retention factor and peak asymmetry factor, and analytical parameters, such as the limit of detection (LOD), limit of quantification (LOQ), linear range, calibration equation, and R(2) value, and quantitative analysis parameters were calculated for all of the analytes. Using different mobile phases, five different classes of aromatic hydrocarbons were separated in a very short analysis time of 4-8min. Furthermore, a high theoretical plate number (up to 25000) and an excellent peak asymmetry factor (1.0) were obtained. The results showed that the surface of the SWNTs had very strong interactions with aromatic groups, therefore providing high selectivity for the separation of different classes of aromatic compounds. This study indicates that SWCNTs enable the extension of the application range of the newly prepared stationary phases for the fast separation of aromatic compounds by HPLC.

  9. Liposome and niosome preparation using a membrane contactor for scale-up.

    Science.gov (United States)

    Pham, Thi Thuy; Jaafar-Maalej, Chiraz; Charcosset, Catherine; Fessi, Hatem

    2012-06-01

    The scaling-up ability of liposome and niosome production, from laboratory scale using a syringe-pump device to a pilot scale using the membrane contactor module, was investigated. For this aim, an ethanol injection-based method was applied for liposome and niosome preparation. The syringe-pump device was used for laboratory scale batches production (30 ml for liposomes, 20 ml for niosomes) then a pilot scale (750 ml for liposomes, 1000 ml for niosomes) were obtained using the SPG membrane contactor. Resulted nanovesicles were characterized in terms of mean vesicles size, polydispersity index (PdI) and zeta potential. The drug encapsulation efficiency (E.E.%) was evaluated using two drug-models: caffeine and spironolactone, a hydrophilic and a lipophilic molecule, respectively. As results, nanovectors mean size using the syringe-pump device was comprised between 82 nm and 95 nm for liposomes and between 83 nm and 127 nm for niosomes. The optimal E.E. of caffeine within niosomes, was found around 9.7% whereas the spironolactone E.E. reached 95.6% which may be attributed to its lipophilic properties. For liposomes these values were about 9.7% and 86.4%, respectively. It can be clearly seen that the spironolactone E.E. was slightly higher within niosomes than liposomes. Optimized formulations, which offered smaller size and higher E.E., were selected for pilot scale production using the SPG membrane. It has been found that vesicles characteristics (size and E.E.%) were reproducible using the membrane contactor module. Thus, the current study demonstrated the usefulness of the membrane contactor as a device for scaling-up both liposome and niosome preparations with small mean sizes.

  10. Simultaneous Estimation of Phenylephrine HCl, Doxylamine Succinate and Dextromethorphan HBr in Soft Gelatin Capsule (Cough and Cold Preparation by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Mo.Salauddin A Shaikh

    2014-05-01

    Full Text Available A RP-HPLC methods were developed and validated for simultaneous estimation of Phenylephrine HCl (PE, Doxylamine Succinate (DOX and Dextromethorphan HBr (DEX. The separation was achieved on a Princestone ODS C18 (250mm X 4.6 mm i.d., 10 μm particle size with an Isocratic system of Phosphate Buffer (10 mM : Methanol : Acetonitrile (pH 4 in the ratio of 70:25:5 v/v/v. The retention time for PE, DOX and DEX was obtained as 5.125 min, 10.419 min and 2.661 min respectively with a flow rate of 1.0 ml/min at detection wavelength 215 nm. The linearity of the proposed method was investigated in the range of 25 -125 μg/ml, 31.25 - 156.25 μg/ml and 50 - 250 μg/ml for PE, DOX and DEX respectively. The developed method was validated as per ICH guideline and found to be satisfactory.

  11. Preparation of Dry Extract of Mikania glomerata Sprengel (Guaco and Determination of Its Coumarin Levels by Spectrophotometry and HPLC-UV

    Directory of Open Access Journals (Sweden)

    Maria da Penha Henriques do Amaral

    2012-08-01

    Full Text Available Guaco (Mikania glomerata Sprengel syrup is one of the most popular herbal medicines used to treat the symptoms of asthmatic bronchitis, cough and hoarseness. The coumarin 2H-1-benzopyran-2-one, is one of the major constituents of Guaco and contributes to its pharmacological effects. The pharmaceutical capsule form of dry extract of Guaco is recommended by the Brazilian Program of Medicinal Plants and Herbal Medicines and used in primary health care. In order to identify a new protocol to obtain the raw material for Guaco capsule production we evaluated two methods, including a freeze-drying process (lyophilization and the spray-dryer technique, as well as the use of two adjuvants, Maltodextrins and Aerosil®, in different concentrations. The coumarin levels of the dried extracts were analyzed by UV-spectrophotometry and HPLC-UV/DAD. The adjuvant Aerosil® 8% showed better dry powder physical appearance. Lyophilization was observed to be the best process to obtain the dry extract of Guaco based on the measured coumarin levels.

  12. Orthogonality of SFC versus HPLC for small molecule library separation.

    Science.gov (United States)

    Weller, Harold N; Ebinger, Katalin; Bullock, William; Edinger, Kurt J; Hermsmeier, Mark A; Hoffman, Steven L; Nirschl, David S; Swann, Thomas; Zhao, Jiang; Kiplinger, Jeffrey; Lefebvre, Paul

    2010-11-08

    Preparative HPLC and HPLC-MS are well established as the methods of choice for purification of pharmaceutical library compounds. Recent advances in supercritical fluid chromatography (SFC) have now made SFC a viable alternative to HPLC for this application. One of the potential arguments for using SFC in place of, or in addition to, HPLC is that it may offer different selectivity and thus has the potential for improved separation success rates. In this paper, we examine relative success rates for SFC and HPLC in obtaining adequate selectivity for successful separation. Our results suggest that use of SFC in addition to HPLC may result in a slight (1-2%) improvement in success rate compared to use of HPLC alone.

  13. [Study on preparation of composite nano-scale Fe3O4 for phosphorus control].

    Science.gov (United States)

    Li, Lei; Pan, Gang; Chen, Hao

    2010-03-01

    Composite nano-scale Fe3O4 particles were prepared in sodium carboxymethyl cellulose (CMC) solution by the oxidation deposition method. The adsorptions of phosphorus by micro-scale Fe3O4 and composite nano-scale Fe3O4 were investigated in water and soil, and the role of cellulase in the adsorption of composite nano-scale Fe3O4 was studied. Kinetic tests indicated that the equilibrium adsorption capacity of phosphorous on the composite nano-scale Fe3O4 (2.1 mg/g) was less than that of micro-scale Fe3O4 (3.2 mg/g). When cellulase was added to the solution of composite nano-scale Fe3O4 to degrade CMC, the removal rate of P by the nanoparticles (86%) was enhanced to the same level as the microparticles (90%). In the column tests, when the composite nano-scale Fe3O4 suspension was introduced in the downflow mode through the soil column, 72% of Fe3O4 penetrated through the soil bed under gravity. In contrast, the micro-scale Fe3O4 failed to pass through the soil column. The retention rate of P was 45% in the soil column when treated by the CMC-stabilized nanoparticles, in comparison with only 30% for the untreated soil column, however it could be improved to 74% in the soil column when treated by both the CMC-stabilized nanoparticles and cellulase, which degraded CMC after the nanoparticles were delivered into the soil.

  14. Preparative-scale enzymic synthesis of D-[14C]ribulose 1,5-bisphosphate.

    Science.gov (United States)

    Kuehn, G D; Hsu, T C

    1978-01-01

    A procedure is described to prepare uniformly labelled D-[14C]ribulose 1,5-bisphosphate enzymically from uniformly labelled D-[14C]glucose through the coupled reactions catalysed by hexokinase (EC 2.7.1.1), glucose 6-phosphate dehydrogenase (EC 1.1.1.49), 6-phosphogluconate dehydrogenase (EC 1.1.1.44) and 5-phosphoribulokinase (EC 2.7.1.19). All reagents utilized in the method are commercially available. The procedure is a reliable preparative-scale method for synthesizing the dibarium salt of D-[14C]ribulose 1,5-biphosphate with a specific radioactivity up to 7 mCi/mmol and a purity near 90%. The final product was free of other 14C-labelled sugars, sugar phosphate esters, Pi and nucleotides. PMID:217356

  15. Hanford Waste Vitrification Plant full-scale feed preparation testing with water and process simulant slurries

    Energy Technology Data Exchange (ETDEWEB)

    Gaskill, J.R.; Larson, D.E.; Abrigo, G.P. [and others

    1996-03-01

    The Hanford Waste Vitrification Plant was intended to convert selected, pretreated defense high-level waste and transuranic waste from the Hanford Site into a borosilicate glass. A full-scale testing program was conducted with nonradioactive waste simulants to develop information for process and equipment design of the feed-preparation system. The equipment systems tested included the Slurry Receipt and Adjustment Tank, Slurry Mix Evaporator, and Melter-Feed Tank. The areas of data generation included heat transfer (boiling, heating, and cooling), slurry mixing, slurry pumping and transport, slurry sampling, and process chemistry. 13 refs., 129 figs., 68 tabs.

  16. Preparation for Scaling Studies of Ice-Crystal Icing at the NRC Research Altitude Test Facility

    Science.gov (United States)

    Struk, Peter M.; Bencic, Timothy J.; Tsao, Jen-Ching; Fuleki, Dan; Knezevici, Daniel C.

    2013-01-01

    This paper describes experiments conducted at the National Research Council (NRC) of Canadas Research Altitiude Test Facility between March 26 and April 11, 2012. The tests, conducted collaboratively between NASA and NRC, focus on three key aspects in preparation for later scaling work to be conducted with a NACA 0012 airfoil model in the NRC Cascade rig: (1) cloud characterization, (2) scaling model development, and (3) ice-shape profile measurements. Regarding cloud characterization, the experiments focus on particle spectra measurements using two shadowgraphy methods, cloud uniformity via particle scattering from a laser sheet, and characterization of the SEA Multi-Element probe. Overviews of each aspect as well as detailed information on the diagnostic method are presented. Select results from the measurements and interpretation are presented which will help guide future work.

  17. 氨基柱HPLC法测定盐酸氨基葡萄糖及其制剂的含量%Content Determination of Glucosamine Hydrochloride and its Preparations by HPLC

    Institute of Scientific and Technical Information of China (English)

    罗立; 但汉雄

    2016-01-01

    目的::建立盐酸氨基葡萄糖及其制剂的 HPLC 含量测定方法。方法:采用 Phenomenex Luna NH2柱(150 mm ×4.6 mm,5 mm);流动相:磷酸盐缓冲液(取磷酸氢二钾3.5 g,加水1000 ml使溶解,加入0.25 ml氨水,用磷酸调节pH至7.5)-乙腈(25∶75);流速:1.5 ml·min-1;检测波长:195 nm;柱温:35℃;进样量20μl。结果:盐酸氨基葡萄糖在1.6~16.0 mg· ml-1浓度范围线性关系良好(r=0.9999),片剂及胶囊的平均回收率分别为99.3%和99.5%,RSD均为0.3%(n=9)。结论:该方法简便、准确,专属性强,适合于盐酸氨基葡萄糖及其制剂的质量控制。%Objective: To establish an HPLC method for determining the content of glucosamine hydrochloride and its prepara-tions. Methods:A Phenomenex Luna NH2 column was used, and the mobile phase was ammonium phosphate buffer (dissolving 3. 5 g dipotassium phosphate and 0. 25 ml ammonium hydroxide into 1 000 ml water, adjusting pH to 7. 5 with phosphoric acid) – acetoni-trile (25 ∶75). The flow rate was 1. 5 ml·min-1 and detection wavelength was 195 nm. The column temperature was 35℃ and the injection volume was 20 μl. Results:The linear range of glucosamine hydrochloride was 1. 6-16. 0 mg·ml-1(r=0. 999 9). The av-erage recovery of glucosamine hydrochloride tablets and capsules was 99. 3% and 99. 5%, respectively, and RSDs were 0. 3% ( n=9). Conclusion:The method is simple, accurate and reliable, and suitable for the quality control of glucosamine hydrochloride and its preparations.

  18. Preparing for the ingestion of SWOT data into continental-scale river models

    Science.gov (United States)

    David, Cédric; Andreadis, Konstantinos; Beighley, Edward; Famiglietti, James; Boone, Aaron; Yamazaki, Dai; Kim, Hyungjun; Gaborit, Etienne

    2016-04-01

    The Surface Water and Ocean Topography (SWOT) mission is currently scheduled to launch at the end of this decade. SWOT should retrieve unprecedented measurements of water extent, elevation, and slope in the largest terrestrial water bodies. Such potential transformative information motivates the investigation of our ability to ingest the associated data into continental-scale models of terrestrial hydrology. In preparation for the expected SWOT observations, an inter-comparison of continental-scale river models is being designed. This comparison experiment focuses on four of the world's largest river basins: the Amazon, the Mississippi, the Niger, and the Saint-Lawrence. This ongoing project focuses on two main research questions: 1) How can we best prepare for the expected SWOT continental to global measurements before SWOT even flies?, and 2) What is the added value of including SWOT terrestrial measurements into global hydro models for enhancing our understanding of the terrestrial water cycle and the climate system? We present here the preliminary architecture of the inter-comparison in hope to motivate community feedback and involvement.

  19. Application of a Stir Bar Sorptive Extraction sample preparation method with HPLC for soil fungal biomass determination in soils from a detrital manipulation study.

    Science.gov (United States)

    Beni, Áron; Lajtha, Kate; Kozma, János; Fekete, István

    2017-05-01

    Ergosterol is a sterol found ubiquitously in cell membranes of filamentous fungi. Although concentrations in different fungal species span the range of 2.6 to 42μg/mL of dry mass, many studies have shown a strong correlation between soil ergosterol content and fungal biomass. The analysis of ergosterol in soil therefore could be an effective tool for monitoring changes in fungal biomass under different environmental conditions. Stir Bar Sorptive Extraction (SBSE) is a new sample preparation method to extract and concentrate organic analytes from liquid samples. SBSE was here demonstrated to be a simple, fast, and cost effective method for the quantitative analysis of ergosterol from field-collected soils. Using this method we observed that soil ergosterol as a measure of fungal biomass proved to be a sensitive indicator of soil microbial dynamics that were altered by changes in plant detrital inputs to soils in a long-term field experiment.

  20. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

  1. 奥利司他的制备液相色谱纯化及其UPLC法测定%Purification of Orlistat by Preparative HPLC and Its Determination by UPLC

    Institute of Scientific and Technical Information of China (English)

    许勇煌; 彭韪; 唐彬喜; 王德刚; 刘德富

    2012-01-01

    A preparative HPLC method was established for the purification of orlistat. 3% Orlistat solution was loaded on the column. It was isocratic eluted with 89% acetonitrile solution and detected at 195 nm. The eluent was collected segmentally. An UPLC method was established for the determination of orlistat in the eluent. An Acquity BEH C18 column was used with the mobile phase of 81 % acetonitrile solution at the detection wavelength of 195 nm. The calibration curve was linear in the range of 0.2 - 1 mg/ml. The recovery was 98.8%, with RSD of 0.16%.%建立了制备液相色谱法纯化奥利司他粗品.取3%奥利司他粗品溶液上样,以89%乙腈溶液为流动相进行洗脱,检测波长195 nm,分段收集洗脱液.采用UPLC法测定洗脱液中的奥利司他,使用Acquity BEH C18色谱柱,流动相为81%乙腈溶液,检测波长195 nm.奥利司他在0.2~1 mg/ml范围内线性关系良好,回收率为98.8%,RSD为0.16%.

  2. Development of an HPLC method to analyze and prepare elsinochrome C and hypocrellin A in the submerged fermentation broth of Shiria sp. SUPER-H168.

    Science.gov (United States)

    Hu, Mingming; Cai, Yujie; Liao, Xiangru; Hao, Zhikui; Liu, Jiayang

    2012-06-01

    A rapid and sensitive analytical method based on reverse-phase high-performance liquid chromatography was first developed to simultaneously determine elsinochrome C (EC) and hypocrellin A (HA) in the submerged fermentation. The mobile phase consisted of acetonitrile-water 60:40 (v/v) with a flow-rate of 1 mL/min. The calibration curves were as follows: y = 37,625x + 249,775 for EC, y = 30,813x + 556,409 for HA and linear at the investigated concentration. The correlation coefficients (R(2) ) were 0.9989 and 0.9998 respectively for EC and HA. The limits of detection and quantification were 175 and 585 µg/L for EC and 205 and 610 µg/L for HA. The precisions of concentration and retention times were less than 2.5 and 0.3%. The recovery of the method was greater than 95.0%. The methodology was applied to analyze simultaneously EC and HA concentrations in a submerged fermentation, and was adequate for analysis of biosynthesis of perylenequinones. The method was also amplified to separate and purify EC and HA using a semi-preparative C(18) column. In addition, elsinochrome C was first identified in the submerged fermentation broth of Shiraia sp. SUPER-H168. Copyright © 2011 John Wiley & Sons, Ltd.

  3. Simultaneous quantitative determination of six active components in traditional Chinese medicinal preparation Cerebralcare Granule® by RP-HPLC coupled with diode array detection for quality control.

    Science.gov (United States)

    Wang, Xiang-yang; Ma, Xiao-hui; Li, Wei; Chu, Yang; Guo, Jia-hua; Zhou, Shui-ping; Zhu, Yong-hong

    2014-09-01

    A simple, accurate and reliable method for the simultaneous separation and determination of six active components (protocatechuic acid, chlorogenic acid, caffeic acid, paeoniflorin, ferulic acid and rosmarinic acid) in traditional Chinese medicinal preparation Cerebralcare Granule(®) (CG) was developed using reverse-phase high-performance liquid chromatography coupled with diode array detector detection. The chromatographic separation was performed on a Hypersil GOLD C18 column with aqueous formic acid (0.1%, v/v) and acetonitrile as mobile phase at a flow rate of 0.2 ml/min at 30 °C. Because of the different UV characteristics of these components, change detection wavelength method was used for quantitative analysis. All of the analytes showed good linearity (r > 0.9992). The established method showed good precision and relative standard deviations (%) for intra-day and inter-day variations of 0.15-1.81 and 0.11-1.98%, respectively. The validated method was successfully applied to the simultaneously determination of six active components in CG from different batches.

  4. Developing a "Self-Directed Learning Preparation Skills Scale for Primary School Students": Validity and Reliability Analyses

    Science.gov (United States)

    Gündüz, Gülten Feryal; Selvi, Kiymet

    2016-01-01

    The purpose of this study is to develop "Self-Directed Learning Preparation Skills Scale" for primary school students. Data were gathered according to the principles of descriptive research method. In order to develop this scale, draft items were developed through review of literature, interviews done with teachers, parents and students…

  5. Determination of surface-adsorbed excipients of various types on drug particles prepared by antisolvent precipitation using HPLC with evaporative light scattering detection.

    Science.gov (United States)

    Zimmermann, Anne; Elema, Michiel Ringkjøbing; Hansen, Tue; Müllertz, Anette; Hovgaard, Lars

    2007-08-15

    A common challenge in the development of new drug substances is poor dissolution characteristics related to low aqueous solubility. One approach to overcome this problem is antisolvent precipitation in the presence of polymers or surfactants, which may enhance the dissolution rate through reduced particle size and increased wettability. In this study, a simple method based on size exclusion chromatography (SEC) with evaporative light scattering detection (ELSD) was developed for the determination of polymers and surfactants adsorbed to drug particles prepared by antisolvent precipitation of the poorly water-soluble model drug Lu 28-179. Detection of many polymeric excipients and surfactants is problematic due to the lack of UV-absorbing chromophores, but ELSD proved successful for the direct determination of the investigated compounds. A mixed mode column was used to effectively separate each of the excipient structures from the drug. The mobile phase comprised acetonitrile-ammonium formate (20mM; pH 6.5) (50:50, v/v) at a flow-rate of 0.6 ml/min. Qualification studies showed that the method was adequately sensitive and precise with limits of detection between 0.72 and 4.32 microg/ml. Linearity of the calibration curves was achieved by log-log modelling. The method was applied for determination of nine polymeric excipients and surfactants adsorbed to particles of the model drug. The extent of excipient adsorption varied between 0.07 and 1.39% (w/w) of the total particle weight.

  6. HPLC法测定乌拉地尔不同制剂中的有关物质%Analysis of the related substances in different urapidil preparations by HPLC

    Institute of Scientific and Technical Information of China (English)

    王嫦鹤; 焦艳; 杜珊; 王莉

    2013-01-01

    目的 建立乌拉地尔注射液、缓释片、缓释胶囊中有关物质测定的HPLC分析方法.方法 采用HPLC-UV法.C18色谱柱(250 mm×4.6 mm,5 μm);以乙腈-0.05 mol·L-1磷酸二氢铵(20∶80)为流动相;检测波长268 nm;流速1.0 mL·min-1;进样体积20 μL.采用乌拉地尔杂质A并制备各种降解产物进行分离度分析.结果 各制剂中,乌拉地尔主峰与杂质峰、辅料峰均有较好的分离度,且重复性较好,可用于乌拉地尔各制剂有关物质的分离与分析.结论 该法简单、准确、专属性强,可用于乌拉地尔不同制剂中有关物质的分析测定.%Objective To establish the determination methods of related substances in urapidil injections,sustained-release tablets,and sustained-release capsules by HPLC-UV. Method The chromatography conditions were as follows :Kromasil C18 column (250 mm ×4. 6 mm, 5μm) ,acetonitrile-0. 05 mol · L-1 ammonium dihydrogen phosphate (20 : 80) as mobile phase, UV detection wave-length 268 nm,flow rate 1. 0 mL · min-1 ,injection volume 20 μL. The resolutions were analyzed by using urapidil impurities A and the degradation products of urapidil. Results The main peak and impurity peaks had good resolution and repeatability for the separation and analysis of related substances. Conclusion The method is simple,accurate and specific,and can be used to analyze the related substances in different urapidil preparations.

  7. A multi-scale controlled tissue engineering scaffold prepared by 3D printing and NFES technology

    Directory of Open Access Journals (Sweden)

    Feifei Yan

    2014-03-01

    Full Text Available The current focus in the field of life science is the use of tissue engineering scaffolds to repair human organs, which has shown great potential in clinical applications. Extracellular matrix morphology and the performance and internal structure of natural organs are required to meet certain requirements. Therefore, integrating multiple processes can effectively overcome the limitations of the individual processes and can take into account the needs of scaffolds for the material, structure, mechanical properties and many other aspects. This study combined the biological 3D printing technology and the near-field electro-spinning (NFES process to prepare a multi-scale controlled tissue engineering scaffold. While using 3D printing technology to directly prepare the macro-scaffold, the compositing NFES process to build tissue micro-morphology ultimately formed a tissue engineering scaffold which has the specific extracellular matrix structure. This scaffold not only takes into account the material, structure, performance and many other requirements, but also focuses on resolving the controllability problems in macro- and micro-forming which further aim to induce cell directed differentiation, reproduction and, ultimately, the formation of target tissue organs. It has in-depth immeasurable significance to build ideal scaffolds and further promote the application of tissue engineering.

  8. Biomimetic preparation and multi-scale microstructures of nano-silica/polyurethane elastomeric fibers

    Institute of Scientific and Technical Information of China (English)

    Quanyong Liu; Li Gao; Lei Jiang

    2013-01-01

    Bioinspired by the spinning of spider silks, the biomimetic preparation of nano-silica/polyurethane (nano-SiO2/TPU) elastomeric fibers with distinctive multi-scale microstructures was successfully implemented. The formation mechanism of the nano-SiO2/TPU fibers was considered as the integrated mechanism of diffusion, coagulation, self-assembly, and microphase separation, same as that of the native spider silks. The mass ratio of nano-SiO2 to TPU greatly influenced the external and inner microstructures of the nano-SiO2/TPU fibers. The formation process of the nano-SiO2/TPU fibers was simply described as three main stages, and the second stage, such as the adding of the ethanol solvents and nano-SiO2 in different diameters, was thought to be very crucial for the final external and inner microstructures of the prepared fibers. For example, the adding of the ethanol and the nano-SiO2 spheres in diameter of 10 nm resulted in the existence of many TPU-self-assembled microspheres mostly spaced apart by the nano-SiO2 aggregates in the nano-SiO2/TPU fibers, while the adding of the ethanol and the nano-SiO2 spheres in diameter of 100 nm resulted in the existence of the nano-SiO2 spheres, instead of the TPU-self-assembled microspheres, distributed in the nano-SiO2/TPU fibers.

  9. A multi-scale controlled tissue engineering scaffold prepared by 3D printing and NFES technology

    Science.gov (United States)

    Yan, Feifei; Liu, Yuanyuan; Chen, Haiping; Zhang, Fuhua; Zheng, Lulu; Hu, Qingxi

    2014-03-01

    The current focus in the field of life science is the use of tissue engineering scaffolds to repair human organs, which has shown great potential in clinical applications. Extracellular matrix morphology and the performance and internal structure of natural organs are required to meet certain requirements. Therefore, integrating multiple processes can effectively overcome the limitations of the individual processes and can take into account the needs of scaffolds for the material, structure, mechanical properties and many other aspects. This study combined the biological 3D printing technology and the near-field electro-spinning (NFES) process to prepare a multi-scale controlled tissue engineering scaffold. While using 3D printing technology to directly prepare the macro-scaffold, the compositing NFES process to build tissue micro-morphology ultimately formed a tissue engineering scaffold which has the specific extracellular matrix structure. This scaffold not only takes into account the material, structure, performance and many other requirements, but also focuses on resolving the controllability problems in macro- and micro-forming which further aim to induce cell directed differentiation, reproduction and, ultimately, the formation of target tissue organs. It has in-depth immeasurable significance to build ideal scaffolds and further promote the application of tissue engineering.

  10. Content Determination of Gallic Acid in Different Preparation Parts of Phyllanthus emblica by HPLC%HPLC法测定余甘子不同提取部位中没食子酸的含量

    Institute of Scientific and Technical Information of China (English)

    轩辕欢; 魏敏; 田红林; 成杰

    2015-01-01

    目的:建立测定余甘子不同提取部位中没食子酸含量的方法.方法:采用高效液相色谱法.色谱柱为ZORBAX Extend C18,流动相为甲醇~0.1%磷酸(10:90,V/V),流速为1.0 ml/min,检测波长为270 nm,柱温为30℃,进样量为10μl.结果:没食子酸检测质量浓度线性范围为0.042 5~0.212 5 mg/ml;精密度、稳定性、重复性试验的RSD<3.0%;加样回收率为99.38%~102.14%(RSD=1.045,n=6).余甘子中没食子酸为1.82%,各不同制备部位没食子酸含量为0.70%~2.38%.结论:该方法操作简便、重复性好,可用于余甘子不同提取部位中没食子酸含量的测定.%OBJECTIVE:To establish a method for the content determination of gallic acid in different preparation parts of Phyl-lanthus emblica. METHODS:HPLC was performed on the column of ZORBAX Extend C18 with mobile phase of methanol-0.1%phosphoric acid (10:90,V/V) at flow rate of 1.0 ml/min,detection wavelength was 270 nm,column temperature was 30 ℃ and the volume injection was 10 μl. RESULTS:The linear range of gallic acid was 0.042 5-0.212 5 mg/ml;RSDs of precision,accura-cy and stability tests were lower than 3.0%;recovery was 99.38%-102.14%(RSD=1.045,n=6). The mass fraction of gallic acid in P. emblica was 1.80%,and the content of gallic acid in different preparation parts was 0.70%-2.38%. CONCLUSIONS:The method is simple,reproducibility,and can be used for the content determination of gallic acid in different preparation parts of P. em-blica.

  11. 反相制备液相色谱同时分离制备独一味中4种环烯醚萜苷类化合物%Simultaneous isolation and preparation of four iridoid glycosides from Lamiophlomis rotata by preparative RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    樊鹏程; 马慧萍; 景临林; 李茂星; 何希瑞; 贾正平

    2012-01-01

    目的 建立独一味中环烯醚萜苷类化合物山栀苷甲酯、螃蟹甲苷Ⅱ、番木鳖苷和8-O-乙酰山栀苷甲酯的快速制备色谱方法.方法 独一味水提物经聚酰胺色谱柱和大孔吸附树脂柱分离后,进行快速制备液相色谱分离,根据制备色谱图收集流出液,采用HPLC和质谱定性定量分析.结果 质谱法确定实验所得4种单体分别为山栀苷甲酯、螃蟹甲苷Ⅱ、番木鳖苷和8-O-乙酰山栀苷甲酯,RP-HPLC法分析质量分数分别为95.7%、94.8%、96.3%、98.2%.结论 该分离方法中各组分分离效果较好,可用于独一味中4种环烯醚萜苷类化合物的分离制备.%Objective To establish a gradient preparative chromatography, RP-HPLC, and mass spectrometry (MS) method for the preparation and identification of four iridoid glycosides from Tibetan medicinal herb Lamiophlomis rotata. Methods After the plant was extracted with water, the crude extract was purified by polyamide column and macroporous adsorptive resins column. Then preparative liquid chromatography was used to isolate shanzhiside methylester, phloyoside II, loganin, and 8-O-acetyl-shanzhiside methylester. The samples were identified by HPLC and MS. Results MS determination indicated that the four monomers were identical to be shanzhiside methylester, phloyoside II, loganin, and 8-O-acetyl-shanzhiside methylester. The results showed that purities of the products were 95.7% (shanzhiside methylester), 94.8% (phloyoside II), 96.3% (loganin), and 98.2% (8-O-acetyl-shanzhiside methylester), respectively. Conclusion The method has good separative effect. It is suitable to be used for the prepared separation of four iridoid glycosides from L. Rotata.

  12. Resin-based preparation of HTGR fuels: operation of an engineering-scale uranium loading system

    Energy Technology Data Exchange (ETDEWEB)

    Haas, P.A.

    1977-10-01

    The fuel particles for recycle of /sup 233/U to High-Temperature Gas-Cooled Reactors are prepared from uranium-loaded carboxylic acid ion exchange resins which are subsequently carbonized, converted, and refabricated. The development and operation of individual items of equipment and of an integrated system are described for the resin-loading part of the process. This engineering-scale system was full scale with respect to a hot demonstration facility, but was operated with natural uranium. The feed uranium, which consisted of uranyl nitrate solution containing excess nitric acid, was loaded by exchange with resin in the hydrogen form. In order to obtain high loadings, the uranyl nitrate must be acid deficient; therefore, nitric acid was extracted by a liquid organic amine which was regenerated to discharge a NaNO/sub 3/ or NH/sub 4/NO/sub 3/ solution waste. Water was removed from the uranyl nitrate solution by an evaporator that yielded condensate containing less than 0.5 ppM of uranium. The uranium-loaded resin was washed with condensate and dried to a controlled water content via microwave heating. The loading process was controlled via in-line measurements of the pH and density of the uranyl nitrate. The demonstrated capacity was 1 kg of uranium per hour for either batch loading contractors or a continuous column as the resin loading contractor. Fifty-four batch loading runs were made without a single failure of the process outlined in the chemical flowsheet or any evidence of inability to control the conditions dictated by the flowsheet.

  13. Standardized laboratory-scale preparation of mayonnaise containing low levels of Salmonella enterica serovar Enteritidis.

    Science.gov (United States)

    Leuschner, R G; Boughtflower, M P

    2001-05-01

    Salmonella enterica serovar Enteritidis PT4 and PT6 are associated with food poisoning outbreaks and are often found in food only in low concentrations. In this study a reproducible laboratory-scale procedure for preparation of mayonnaise is presented. The mayonnaise that simulates a naturally low-level contaminated product can be used for validation of new methods and is also suitable to study the behavior of low numbers of food pathogenic spoilage microorganisms in a food environment. During processing, liquid egg was artificially contaminated with low levels of S. enterica serovar Enteritidis that resulted in levels of 1 to 3 log10 CFU/g in the final mayonnaise. Cells of S. enterica serovar Enteritidis had increased stability in the mayonnaise when they were subjected to low pH in two stages, first to pH 5.8 and afterward to pH 4.5 before addition to the mayonnaise. The pH of the mayonnaise was between 4.2 to 4.5 and remained stable over the storage period. Low-level S. enterica serovar Enteritidis remained stable in artificially contaminated mayonnaise for 4 weeks at 4 degrees C.

  14. Ultrafast and large scale preparation of superior catalyst for oxygen evolution reaction

    Science.gov (United States)

    Tian, Xianqing; Liu, Yunhua; Xiao, Dan; Sun, Jie

    2017-10-01

    The development of efficient and earth abundant catalyst for the oxygen evolution reaction (OER) is a key challenge for the renewable energy research community. Here, we report a facile and ultrafast route to immobilize nickel-iron layered double hydroxide (NiFe-LDH) nanoparticles on nickel foam (NF) via soaking the direct electroless deposited prussian blue analogue (PBA) on NF in 1 M KOH. This NiFe-LDH/NF electrode can be prepared in a few seconds without further treatments. It has three-dimensional interpenetrating network originated from its PBA precursor which facilitate the diffusion and ad/desorption of the reactants and producing for OER. And further characterization of the Faradaic efficiency and forced convection tests show direct evidence to demonstrate the formation of free intermediate(s) in the OER process. This electrode (typically NiFe-LDH-20s/NF) exhibits outstanding electrocatalytic activity with low overpotential of ∼0.240 V at 10 mA cm-2, low Tafel slope of 38 mV dec-1, and great stability. This feasible strategy affords a new strategy for the large scale manufacture of low-cost, effective and robust OER electrodes.

  15. Preparation of a new chiral stationary phase for HPLC based on the (R)- 1-phenyl-2-(4-methylphenyl)ethylamine amide derivative of (S)-valine and 2-chloro-3,5-dinitrobenzoic acid: enantioseparation of amino acid derivatives and pyrethroid insecticides.

    Science.gov (United States)

    Tan, Xulin; Hou, Shicong; Jiang, Jingli; Wang, Min

    2007-08-01

    A novel chiral stationary phase (CSP) for HPLC was prepared by bonding (R)-1-phenyl-2-(4-methylphenyl)ethylamine amide derivative of (S)-valine to aminopropyl silica gel through a 2-amino-3,5-dinitro-1-carboxamido-benzene unit. The CSP was used for the separation of some amino acid derivatives and pyrethroid insecticides by chiral HPLC. Satisfactory baseline separation required optimization of the variables of mobile phase composition. Use of dichloromethane as modifier in the mobile phase gave baseline separations of amino acid derivatives. The two enantiomers of fenpropathrin and four stereoisomers of fenvalerate were baseline separated using hexane-dichloromethane-ethanol as mobile phase. The results show that the enantioselectivity of the new CSP is better than Pirkle type 1-A column for these compounds. Only partial separations were observed for the stereoisomers of cypermethrin and cyfluthrin, which gave even and eight peaks, respectively.

  16. Two-dimensional preparative liquid chromatography system for preparative separation of minor amount components from complicated natural products

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Ying-Kun, E-mail: qyk@xmu.edu.cn; Chen, Fang-Fang; Zhang, Ling-Ling; Yan, Xia; Chen, Lin; Fang, Mei-Juan; Wu, Zhen, E-mail: wuzhen@xmu.edu.cn

    2014-04-01

    Highlights: • Preparative MDLC system was developed for separation of complicated natural products. • Medium-pressure LC and preparative HPLC were connected by interface of SPE. • Automated multi-step preparative separation of 25 compounds was achieved by using this system. - Abstract: An on-line comprehensive two-dimensional preparative liquid chromatography system was developed for preparative separation of minor amount components from complicated natural products. Medium-pressure liquid chromatograph (MPLC) was applied as the first dimension and preparative HPLC as the second one, in conjunction with trapping column and makeup pump. The performance of the trapping column was evaluated, in terms of column size, dilution ratio and diameter-height ratio, as well as system pressure from the view of medium pressure liquid chromatograph. Satisfactory trapping efficiency can be achieved using a commercially available 15 mm × 30 mm i.d. ODS pre-column. The instrument operation and the performance of this MPLC × preparative HPLC system were illustrated by gram-scale isolation of crude macro-porous resin enriched water extract of Rheum hotaoense. Automated multi-step preparative separation of 25 compounds, whose structures were identified by MS, {sup 1}H NMR and even by less-sensitive {sup 13}C NMR, could be achieved in a short period of time using this system, exhibiting great advantages in analytical efficiency and sample treatment capacity compared with conventional methods.

  17. 液-质联用测定克拉维酸钾及其制剂的含量%HPLC-MS determination of the contents of clavulanate potassium preparations

    Institute of Scientific and Technical Information of China (English)

    孙倩; 张兰桐; 王永利; 刘桂军; 康辉

    2011-01-01

    OBJECTIVE To establish an HPLC-MS method for the determination of the contents of clavulanate potassium preparations.METHODS The Restek C18 column was used, and the mobile phase was 5 mmol· L-1 amine acetate buffer-acetonitrile (90∶ 10) at a flow rate of 0.7 mL·min-1.Column temperature was 25 ℃.The analysis was detected by a negative electrospray ionization(ESI) method under multiple reaction monitoring(MRM) mode.RESULTS The linear range of clavulanate potassium was 1 0.33-1033 μg· L-1 (r = 0.9989), the average recovery of amoxicillin-clavulanate potassium(7∶1 ) dispersible tablet was 98.4% with RSD of 0.97%(n = 9), that of amoxicillin-clavulanate potassium(4∶1 ) suspension was 98.9% with RSD of 1.1% (n = 9) , the LOD was 1.033 μg· L 1.CONCLUSION The method is rapid and accurate, it may provide a new reliable means for the quality control of clavulanate potassium preparations.%目的:建立液-质联用法测定克拉维酸钾及其制剂的含量.方法:采用Restek C18色谱柱,流动相为5 mmol·L-1醋酸铵溶液-乙腈(90:10),流速0.7 mL·min1,柱温25℃;采用ESI离子源,多反应监测(MRM)扫描方式,负离子模式.结果:克拉维酸钾在10.33~1033μg·L1范围内线性关系良好,相关系数为0.9989.阿莫西林克拉维酸钾(7:1)分散片的平均回收率(n=9)为98.4%,RSD为0.97%;阿莫西林克拉维酸钾(4:1)干混悬剂的平均回收率(n=9)为98.9%.RSD为1.1%;最低检测限为1.033/μg·L-1.结论:本方法准确、快速,为克拉维酸钾及其制剂生产中的质量控制提供新的分析手段.

  18. Detection of Illegal Added Acetaminophen in Yinqiao Jiedu Preparation by HPLC%HPLC法检测银翘解毒制剂中非法添加的对乙酰氨基酚

    Institute of Scientific and Technical Information of China (English)

    邱国俊; 许亚玲; 田静; 何咏梅

    2013-01-01

    OBJECTIVE:To establish a method for determining whether there are illegal added acetaminophen in Yinqiao jiedu preparation.METHODS:HPLC method was adopted.The determination was performed on Waters C18(250 min×5.0 mm,4.6 μm)column with mobile phase consisted of methanol-glacial acetic acid (2∶98,V/V) at the flow rate of 1 ml/min.The detection wavelength was set at 249 nm,and column temperature was set at 30 ℃.The sample size was 5 μl.205 batches of samples from 73 factories were determined under the same condition.A positive control was made by adding appropriate amount of reference substance into samples in which acetaminophen was not detected.RESULTS:The linear range of acetaminophen was 0.050 7-1.010 4 μg(r=0.9999).The examination limits was 0.4 ng.Average recoveries of Yinqiao jiedu preparations (tablets,pills,particles) were 99.9%(RSD=0.7%,n=6),96.9% (RSD=0.6%,n=6) and 97.6% (RSD=0.4%,n=6),respectively.Acetaminophen were detected in positive reference substance and not detected in 205 batches of samples.CONCLUSIONS:The method is specific,sensitive and simple,and can be used to detect illegal added acetaminophen in Chinese patent medicine.%目的:建立检测银翘解毒制剂中是否非法添加解热镇痛药对乙酰氨基酚的方法.方法:采用高效液相色谱法.色谱柱为Waters C18(250 mm×5.0 mm,4.6μm),流动相为甲醇-0.5%冰醋酸溶液(2∶98,V/V),检测波长为249nm,柱温为30℃,流速为1 ml/min,进样量为5μl.在此条件下检测了73个厂家205批样品,并在未检出对乙酰氨基酚的样品中添加适量对照品作为阳性参比对照进行检测.结果:对乙酰氨基酚的进样量在0.0507~1.0104μg范围内与其峰面积积分值呈良好的线性关系(r=0.9999);检出限为0.4 ng.银翘解毒片、丸、颗粒的平均加样回收率分别为99.9%(RSD=0.7%,n=6)、96.9%(RSD=0.6%,n=6)、97.6%(RSD=0.4%,n=6).阳性参比对照均检出对乙酰氨基酚,205批样品均未检出.结论

  19. Prepare dispersed CIS nano-scale particles and spray coating CIS absorber layers using nano-scale precursors.

    Science.gov (United States)

    Liou, Jian-Chiun; Diao, Chien-Chen; Lin, Jing-Jenn; Chen, Yen-Lin; Yang, Cheng-Fu

    2014-01-01

    In this study, the Mo-electrode thin films were deposited by a two-stepped process, and the high-purity copper indium selenide-based powder (CuInSe2, CIS) was fabricated by hydrothermal process by Nanowin Technology Co. Ltd. From the X-ray pattern of the CIS precursor, the mainly crystalline phase was CIS, and the almost undetectable CuSe phase was observed. Because the CIS powder was aggregated into micro-scale particles and the average particle sizes were approximately 3 to 8 μm, the CIS power was ground into nano-scale particles, then the 6 wt.% CIS particles were dispersed into isopropyl alcohol to get the solution for spray coating method. Then, 0.1 ml CIS solution was sprayed on the 20 mm × 10 mm Mo/glass substrates, and the heat treatment for the nano-scale CIS solution under various parameters was carried out in a selenization furnace. The annealing temperature was set at 550°C, and the annealing time was changed from 5 to 30 min, without extra Se content was added in the furnace. The influences of annealing time on the densification, crystallization, resistivity (ρ), hall mobility (μ), and carrier concentration of the CIS absorber layers were well investigated in this study.

  20. Evaluation of extraction methods for preparative scale obtention of mangiferin and lupeol from mango peels (Mangifera indica L.).

    Science.gov (United States)

    Ruiz-Montañez, G; Ragazzo-Sánchez, J A; Calderón-Santoyo, M; Velázquez-de la Cruz, G; de León, J A Ramírez; Navarro-Ocaña, A

    2014-09-15

    Bioactive compounds have become very important in the food and pharmaceutical markets leading research interests seeking efficient methods for extracting these bioactive substances. The objective of this research is to implement preparative scale obtention of mangiferin and lupeol from mango fruit (Mangifera indica L.) of autochthonous and Ataulfo varieties grown in Nayarit, using emerging extraction techniques. Five extraction techniques were evaluated: maceration, Soxhlet, sonication (UAE), microwave (MAE) and high hydrostatic pressures (HHP). Two maturity stages (physiological and consumption) as well as peel and fruit pulp were evaluated for preparative scale implementation. Peels from Ataulfo mango at consumption maturity stage can be considered as a source of mangiferin and lupeol using the UEA method as it improves extraction efficiency by increasing yield and shortening time. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Electrochemical performance of nano-scale β-Ni(OH)2 prepared at different transformations of pH value

    Institute of Scientific and Technical Information of China (English)

    ZHAO Li; ZHANG Li-jun; HAN Xi-jiang; ZHANG Cui-fen

    2008-01-01

    The influence of transforming pH values on the electrochemical performance of nano-scale Ni(OH)2was analyzed. The measurement results of XRD indicate that the nano-scale Ni (OH)2 prepared at different transformations of pH value is β( Ⅱ )-phase with different crystal lattice parameters. Cyclic voltammograms (CV) and electrochemical impedance spectroscopy(EIS) measurement results show that transformations of pH value affect the proton diffusion coefficient (D) and charge-transfer resistance (Rct) of the material. The simu-lation of cell experiment shows that the sample prepared at a pH of 10. 1 exhibits the maximum specific capacity(327. 8 mAh/g) and higher discharge platform, the discharge performance of electrodes depends on both D and Rct, so the kinetics characteristics that electrodes reaction is controlled by both mass-transfer step and charge-transfer step are put forward.

  2. Preparation of Bovine Serum Albumin (BSA) nanoparticles by desolvation using a membrane contactor: a new tool for large scale production.

    Science.gov (United States)

    Yedomon, B; Fessi, H; Charcosset, C

    2013-11-01

    Albumin nanoparticles are attractive drug delivery systems as they can be prepared under soft conditions and incorporate several kinds of molecules. The aim of this study was to upscale the desolvation process for preparing Bovine Serum Albumin (BSA) nanoparticles using a membrane contactor. At a first step, the BSA nanoparticles were prepared at small scale using a syringe pump. BSA nanoparticles of 139 nm in size, with a polydispersity index of 0.046, were obtained at the optimal conditions: pH 8.2, 100 mg mL(-1) BSA albumin solution (2 mL), and 1 mL min(-1) flow rate of ethanol addition (8 mL). The upscaling with a membrane contactor was achieved by permeating ethanol through the pores of a Shirasu Porous Glass (SPG Technology Co., Japan) membrane and circulating the aqueous phase tangentially to the membrane surface. By increasing the pressure of the ethanol from 1 to 2.7 bars, a progressive decrease in nanoparticle size was obtained with a high nanoparticles yield (around 94-96%). In addition, the flow rate of the circulating phase did not affect the BSA nanoparticle characteristics. At the optimal conditions (pH 8.2, 100 mg mL(-1) BSA albumin solution, pressure of ethanol 2.7 bars, flow rate of the circulating phase 30.7 mL s(-1)), the BSA nanoparticles showed similar characteristics to those obtained with the syringe pump. Large batches of BSA nanoparticles were prepared up to 10 g BSA. The BSA nanoparticles were stable at least during 2 months at 4 °C, and their characteristics were reproducible. It was then concluded that the membrane contactor technique could be a suitable method for the preparation of albumin nanoparticles at large scale with properties similar to that obtained at small scale.

  3. A simple enzymic method for the synthesis of adenosine 5'-[alpha-32P]triphosphate on a preparative scale.

    Science.gov (United States)

    Martin, B R; Voorheis, H P

    1977-03-01

    A simple, rapid and inexpensive method is described for the enzymic synthesis of [alpha-32P]ATP from [32P]Pi on a preparative scale with an overall yield of 53%. The final product contained all of the detectable radioactivity (less than 99.9%) in the alpha position and has been shown to behave identically with commerically availabe [alpha-32P]ATP during the synthesis of 3':5'-cyclic AMP in the reaction catalysed by adenylate cyclase.

  4. Comparison of preparative method during determination of tartrazine and sunset yellow water-solubility colour by HPLC in drinks%HPLC法测定饮料中色素柠檬黄、日落黄前处理方法的比较

    Institute of Scientific and Technical Information of China (English)

    蔡增轩; 黄百芬; 王天娇; 冯靓; 任一平

    2011-01-01

    Objective: Comparison of two preparative method during determination of tartrazine and sunset yellow water - solubility colour by HPLC in drinks. Methods: Preparation samples with two method respectively, and test the result with F - test and t - test after separation with HPLC. Rsesults: F - test were performed on the results of two methods, Fc < Ft. t - test were performed on the result after adjustment with recovery, tc < tt. Conclusion: There were no significant difference between two preparative methods.%目的:对HPLC法测定饮料中人工合成色素柠檬黄、日落黄时两种前处理方法进行比较.方法:分别以稀释和聚酰胺吸附处理样品,经色谱分离后对计算结果进行统计处理,对结果进行F检验和t检验.结果:经对两种前处理方法的结果进行F检验,F.经对回收率校正后的结果进行t检验,t.结论:两种前处理方法的精密度和平均值无显著性差异.

  5. Study of Large-Scale Aluminium-Doped Zinc Oxide Ceramic Targets Prepared by Slip Casting

    Directory of Open Access Journals (Sweden)

    Ling-yun Han

    2016-01-01

    Full Text Available Aluminium-doped zinc oxide (AZO ceramic green compacts at a size of 170 × 340 × 17 mm have been prepared by slip casting. An AZO slurry with good fluidity and viscosity was obtained when 1.2 wt% of dispersant was added, which indicates that the slurry prepared with micrometre particles is more suitable for slip casting. The densification and electrical properties of the AZO targets prepared by particles with different sizes were investigated after sintering from 1380 to 1460°C. The results showed that the relative density of the AZO target prepared with 45 nm particles could reach nearly 98% at 1380°C; the resistivity of the AZO target prepared with nanometre particles could be as low as 1.6 × 10−3 Ω·cm at 1400°C; and the average transmittance of the AZO film prepared with nanometre particles could reach a maximum value of 93.73% in the visible region at 250 W. In this study, the correlation between the density, resistivity, and grain growth of AZO ceramic green compacts was studied.

  6. Compounds and structure identiifcation in extracts from Camellia oleifera leaves by HPLC preparation%液相制备油茶叶提取物组分及其结构鉴定

    Institute of Scientific and Technical Information of China (English)

    曹清明; 钟海雁; 邬靖宇; 包莉圆; 孙亚娟

    2015-01-01

    In order to comprehensively develop and utilize Camellia oleifera resources, compounds in extracts from C. oleifera leaves were separated and identified. Three extracted parts of II, III and VIII from C. oleifera leaves were separated, purified and collected by using macroporous resin and column chromatography, and eight high-purity compounds were achieved by HPLC preparation. Four compounds were identified by methods of TLC colouring, high resolution LC-MS, and NMR, including dihydroresveratrol (1), quercetin (3), quercetin 3-O-β-D-rhamnoside (6) and 1-(3′, 5′-dimethoxy) phenyl-2-[4″-O-β-D-glucopyranosyl (6→1)-O-α-L-rhamnopyranosyl] phenylethane (8). Among the four compounds, the compounds 3 and 6 were very popular flavonoids in C. oleifera, and this was the second time that the compounds 8 was reported, but the extraction rate was higher than that in the first report. This was the first time that dihydroresveratrol was reported in Camellia.%为了综合开发利用油茶资源,对油茶叶提取物的组分进行了制备和鉴定。将经过大孔树脂和柱分离纯化收集的组分II、III和VIII等油茶叶提取物3个组分进行了HPLC制备,得到了8个纯度较高的化合物,通过薄层显色、高清晰质谱和NMR,鉴定了其中4个化合物为:二氢白藜芦醇(1)、槲皮素(3)、槲皮素-3-鼠李糖苷(6)、1-(3′,5′-二甲氧基)苯基2-[4″-O-β-D-吡喃葡萄糖基(6→1)-O-α-L-吡喃鼠李糖基]苯乙烷(8),其中槲皮素和槲皮素-3-鼠李糖苷是油茶中最常见的2个黄酮类物质,1-(3′,5′-二甲氧基)苯基2-[4′-O-β-D-吡喃葡萄糖基(6→1)-O-α-L-吡喃鼠李糖基]苯乙烷为第2次报道,但提取率远高于首次报道,二氢白藜芦醇在山茶属植物中属首次报道。

  7. Measuring Parent Time Scarcity and Fatigue as Barriers to Meal Planning and Preparation: Quantitative Scale Development

    Science.gov (United States)

    Storfer-Isser, Amy; Musher-Eizenman, Dara

    2013-01-01

    Objective: To examine the psychometric properties of 9 quantitative items that assess time scarcity and fatigue as parent barriers to planning and preparing meals for their children. Methods: A convenience sample of 342 parents of children aged 2-6 years completed a 20-minute online survey. Exploratory factor analysis was used to examine the…

  8. HPLC: Early and Recent Perspectives.

    Science.gov (United States)

    Karger, Barry L.

    1997-01-01

    Provides a perspective on what it was like in the early days of high-performance liquid chromatography (HPLC) and several of the key developments. Focuses on the advances in HPLC generally, and more specifically for the biological sciences, that were necessary for the method to reach the preeminent stage of today. Contains 20 references. (JRH)

  9. HPLC: Early and Recent Perspectives.

    Science.gov (United States)

    Karger, Barry L.

    1997-01-01

    Provides a perspective on what it was like in the early days of high-performance liquid chromatography (HPLC) and several of the key developments. Focuses on the advances in HPLC generally, and more specifically for the biological sciences, that were necessary for the method to reach the preeminent stage of today. Contains 20 references. (JRH)

  10. Preparative Scale Resolution of Enantiomers Enables Accelerated Drug Discovery and Development.

    Science.gov (United States)

    Leek, Hanna; Andersson, Shalini

    2017-01-18

    The provision of pure enantiomers is of increasing importance not only for the pharmaceutical industry but also for agro-chemistry and biotechnology. In drug discovery and development, the enantiomers of a chiral drug depict unique chemical and pharmacological behaviors in a chiral environment, such as the human body, in which the stereochemistry of the chiral drugs determines their pharmacokinetic, pharmacodynamic and toxicological properties. We present a number of challenging case studies of up-to-kilogram separations of racemic or enriched isomer mixtures using preparative liquid chromatography and super critical fluid chromatography to generate individual enantiomers that have enabled the development of new candidate drugs within AstraZeneca. The combination of chromatography and racemization as well as strategies on when to apply preparative chiral chromatography of enantiomers in a multi-step synthesis of a drug compound can further facilitate accelerated drug discovery and the early clinical evaluation of the drug candidates.

  11. Preparative Scale Resolution of Enantiomers Enables Accelerated Drug Discovery and Development

    Directory of Open Access Journals (Sweden)

    Hanna Leek

    2017-01-01

    Full Text Available The provision of pure enantiomers is of increasing importance not only for the pharmaceutical industry but also for agro-chemistry and biotechnology. In drug discovery and development, the enantiomers of a chiral drug depict unique chemical and pharmacological behaviors in a chiral environment, such as the human body, in which the stereochemistry of the chiral drugs determines their pharmacokinetic, pharmacodynamic and toxicological properties. We present a number of challenging case studies of up-to-kilogram separations of racemic or enriched isomer mixtures using preparative liquid chromatography and super critical fluid chromatography to generate individual enantiomers that have enabled the development of new candidate drugs within AstraZeneca. The combination of chromatography and racemization as well as strategies on when to apply preparative chiral chromatography of enantiomers in a multi-step synthesis of a drug compound can further facilitate accelerated drug discovery and the early clinical evaluation of the drug candidates.

  12. Multi-Scale Microstructural Thermoelectric Materials: Transport Behavior, Non-Equilibrium Preparation, and Applications.

    Science.gov (United States)

    Su, Xianli; Wei, Ping; Li, Han; Liu, Wei; Yan, Yonggao; Li, Peng; Su, Chuqi; Xie, Changjun; Zhao, Wenyu; Zhai, Pengcheng; Zhang, Qingjie; Tang, Xinfeng; Uher, Ctirad

    2017-01-23

    Considering only about one third of the world's energy consumption is effectively utilized for functional uses, and the remaining is dissipated as waste heat, thermoelectric (TE) materials, which offer a direct and clean thermal-to-electric conversion pathway, have generated a tremendous worldwide interest. The last two decades have witnessed a remarkable development in TE materials. This Review summarizes the efforts devoted to the study of non-equilibrium synthesis of TE materials with multi-scale structures, their transport behavior, and areas of applications. Studies that work towards the ultimate goal of developing highly efficient TE materials possessing multi-scale architectures are highlighted, encompassing the optimization of TE performance via engineering the structures with different dimensional aspects spanning from the atomic and molecular scales, to nanometer sizes, and to the mesoscale. In consideration of the practical applications of high-performance TE materials, the non-equilibrium approaches offer a fast and controllable fabrication of multi-scale microstructures, and their scale up to industrial-size manufacturing is emphasized here. Finally, the design of two integrated power generating TE systems are described-a solar thermoelectric-photovoltaic hybrid system and a vehicle waste heat harvesting system-that represent perhaps the most important applications of thermoelectricity in the energy conversion area.

  13. Preparation and scale up of extended-release tablets of bromopride

    Directory of Open Access Journals (Sweden)

    Guilherme Neves Ferreira

    2014-04-01

    Full Text Available Reproducibility of the tablet manufacturing process and control of its pharmaceutics properties depends on the optimization of formulation aspects and process parameters. Computer simulation such as Design of Experiments (DOE can be used to scale up the production of this formulation, in particular for obtaining sustained-release tablets. Bromopride formulations are marketed in the form of extended-release pellets, which makes the product more expensive and difficult to manufacture. The aim of this study was to formulate new bromopride sustained release formulations as tablets, and to develop mathematical models to standardize the scale up of this formulation, controlling weight and hardness of the tablets during manufacture according to the USP 34th edition. DOE studies were conducted using Minitab(tm software. Different excipient combinations were evaluated in order to produce bromopride sustained-release matrix tablets. In the scale-up study, data were collected and variations in tableting machine parameters were measured. Data were processed by Minitab(tm software, generating mathematical equations used for prediction of powder compaction behavior, according to the settings of the tableting machine suitable for scale-up purposes. Bromopride matrix tablets with appropriate characteristics for sustained release were developed. The scale-up of the formulation with the most suitable sustained release profile was established by using mathematical models, indicating that the formulation can be a substitute for the pellets currently marketed.

  14. Low pressure hand made PVD system for high crystalline metal thin film preparation in micro-nanometer scale

    Energy Technology Data Exchange (ETDEWEB)

    Rosikhin, Ahmad, E-mail: a.rosikhin86@yahoo.co.id; Hidayat, Aulia Fikri; Marimpul, Rinaldo; Syuhada, Ibnu; Winata, Toto, E-mail: toto@fi.itb.ac.id [Department of physics, physics of electronic materials research division Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jl. Ganesha 10, Bandung 40132, Jawa Barat – Indonesia (Indonesia)

    2016-02-08

    High crystalline metal thin film preparation in application both for catalyst substrate or electrode in any electronic devices always to be considered in material functional material research and development. As a substrate catalyst, this metal take a role as guidance for material growth in order to resulted in proper surface structure although at the end it will be removed via etching process. Meanwhile as electrodes, it will dragging charges to be collected inside. This brief discussion will elaborate general fundamental principle of physical vapor deposition (PVD) system for metal thin film preparation in micro-nanometer scale. The influence of thermodynamic parameters and metal characteristic such as melting point and particle size will be elucidated. Physical description of deposition process in the chamber can be simplified by schematic evaporation phenomena which is supported by experimental measurement such as SEM and XRD.

  15. Nanogram-scale preparation and NMR analysis for mass-limited small volatile compounds.

    Directory of Open Access Journals (Sweden)

    Satoshi Nojima

    Full Text Available Semiochemicals are often produced in infinitesimally small quantities, so their isolation requires large amounts of starting material, not only requiring significant effort in sample preparation, but also resulting in a complex mixture of compounds from which the bioactive compound needs to be purified and identified. Often, compounds cannot be unambiguously identified by their mass spectra alone, and NMR analysis is required for absolute chemical identification, further exacerbating the situation because NMR is relatively insensitive and requires large amounts of pure analyte, generally more than several micrograms. We developed an integrated approach for purification and NMR analysis of <1 µg of material. Collections from high performance preparative gas-chromatography are directly eluted with minimal NMR solvent into capillary NMR tubes. With this technique, (1H-NMR spectra were obtained on 50 ng of geranyl acetate, which served as a model compound, and reasonable H-H COSY NMR spectra were obtained from 250 ng of geranyl acetate. This simple off-line integration of preparative GC and NMR will facilitate the purification and chemical identification of novel volatile compounds, such as insect pheromones and other semiochemicals, which occur in minute (sub-nanogram, and often limited, quantities.

  16. Synthesis of oligodeoxyribonucleotides by solid phase phosphotriester method on a reduced scale; preparation of oligonucleotides for improved promoter sequence.

    Science.gov (United States)

    Naruto, M

    1982-01-01

    A small reaction vessel, composed of a balled sintered glass filter and a test tube with a stopcock, was designed for the solid phase phosphotriester synthesis of oligodeoxyribonucleotide. Operation of small scale synthesis (nucleoside on resin: 3-6 mumol, activated diester of dimer: 20-30 mumol) was performed under the atmosphere of argon. The yield of each coupling reaction was 60-100%. Twelve short oligonucleotides (6-16mer) were obtained in 19-78% overall yield by this method. These oligomers were prepared as a part of the control region of gene to increase the translation efficiency.

  17. The Forel-Ule Scale Revisited Spectrally: Preparation Protocol, Transmission Measurements and Chromaticity

    Science.gov (United States)

    Novoa, S.; Wernand, M. R.; van der Woerd, H. J.

    2013-08-01

    The Forel-Ule colour comparator scale has been applied globally and intensively by oceanographers and limnologists since the 19th century,providing one of the oldest oceanographic data sets. Present and future Forel-Ule classifications of global oceanic, coastal and continentalwaters can facilitate the interpretation of these long-term ocean colour data series and provide a connection between the present and thepast that will be valuable for climate-related studies. Within the EC-funded project CITLOPS (Citizens' Observatory for Coast and Ocean Optical Monitoring), with its main goal to empower endusers,willing to employ community-based environmental monitoring, our aim is to digitalize the colours of the Forel-Ule scale to establishthe colour of natural waters through smartphone imaging. The objective of this study was to reproduce the Forel-Ule scale following theoriginal recipes, measure the transmission of the solutions and calculate the chromaticity coordinates of the scale as Wernand and Vander Woerd did in 2010, for the future development of a smartphone application. Some difficulties were encountered when producing thescale, so a protocol for its consistent reproduction was developed and is described in this study. Recalculated chromaticity coordinates arepresented and compared to measurements conducted by former scientists. An error analysis of the spectral and colourimetric informationshows negligible experimental errors.

  18. LATTICE DEFORMATION AND PHASE TRANSFORMATION FROM NANO-SCALE ANATASE TO NANO-SCALE RUTILE TiO2 PREPARED BY A SOL-GEL TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    Yanqun Shao; Dian Tang; Jinghua Sun; Yekun Lee; Weihao Xiong

    2004-01-01

    Nano-scale rutile phase was transformed from nano-scale anatase upon heating, which was prepared by a sol-gel technique. The XRD data corresponding to the anatase and rutile phases were analyzed and the grain sizes of as-derived phases were calculated by Sherrer equation. The lattice parameters of the as-derived anatase and rutile unit cells were calculated and compared with those of standard lattice parameters on PDF cards. It was shown that the smaller the grain sizes, the larger the lattice deformation. The lattice parameter a has the negative deviation from the standard and the lattice parameter c has the positive deviation for both phases. The particles sizes had preferential influence on the longer parameter between the lattice parameters of a and c. With increasing temperatures, the lattice parameters of a and c in both phases approached to the equilibrium state. The larger lattice deformation facilitated the nucleation process, which lowered the transformation temperature. During the transformation from nano-scale anatase to rutile, besides the mechanism involving retention of the {112} pseudo-close-packed planes of oxygen in anatase as the{100} pseudo-close-packed planes in rutile, the new phase occurred by relaxation of lattice deformation and adjustment of the atomic sites in parent phase. The orientation relationships were suggested to be anatase {101}//rutile {101} and anatase //rutile, and the habit plane was anatase (101),

  19. Indomethacin nanocrystals prepared by different laboratory scale methods: effect on crystalline form and dissolution behavior

    Energy Technology Data Exchange (ETDEWEB)

    Martena, Valentina; Censi, Roberta [University of Camerino, School of Pharmacy (Italy); Hoti, Ela; Malaj, Ledjan [University of Tirana, Department of Pharmacy (Albania); Di Martino, Piera, E-mail: piera.dimartino@unicam.it [University of Camerino, School of Pharmacy (Italy)

    2012-12-15

    The objective of this study is to select very simple and well-known laboratory scale methods able to reduce particle size of indomethacin until the nanometric scale. The effect on the crystalline form and the dissolution behavior of the different samples was deliberately evaluated in absence of any surfactants as stabilizers. Nanocrystals of indomethacin (native crystals are in the {gamma} form) (IDM) were obtained by three laboratory scale methods: A (Batch A: crystallization by solvent evaporation in a nano-spray dryer), B (Batch B-15 and B-30: wet milling and lyophilization), and C (Batch C-20-N and C-40-N: Cryo-milling in the presence of liquid nitrogen). Nanocrystals obtained by the method A (Batch A) crystallized into a mixture of {alpha} and {gamma} polymorphic forms. IDM obtained by the two other methods remained in the {gamma} form and a different attitude to the crystallinity decrease were observed, with a more considerable decrease in crystalline degree for IDM milled for 40 min in the presence of liquid nitrogen. The intrinsic dissolution rate (IDR) revealed a higher dissolution rate for Batches A and C-40-N, due to the higher IDR of {alpha} form than {gamma} form for the Batch A, and the lower crystallinity degree for both the Batches A and C-40-N. These factors, as well as the decrease in particle size, influenced the IDM dissolution rate from the particle samples. Modifications in the solid physical state that may occur using different particle size reduction treatments have to be taken into consideration during the scale up and industrial development of new solid dosage forms.

  20. Indomethacin nanocrystals prepared by different laboratory scale methods: effect on crystalline form and dissolution behavior

    Science.gov (United States)

    Martena, Valentina; Censi, Roberta; Hoti, Ela; Malaj, Ledjan; Di Martino, Piera

    2012-12-01

    The objective of this study is to select very simple and well-known laboratory scale methods able to reduce particle size of indomethacin until the nanometric scale. The effect on the crystalline form and the dissolution behavior of the different samples was deliberately evaluated in absence of any surfactants as stabilizers. Nanocrystals of indomethacin (native crystals are in the γ form) (IDM) were obtained by three laboratory scale methods: A (Batch A: crystallization by solvent evaporation in a nano-spray dryer), B (Batch B-15 and B-30: wet milling and lyophilization), and C (Batch C-20-N and C-40-N: Cryo-milling in the presence of liquid nitrogen). Nanocrystals obtained by the method A (Batch A) crystallized into a mixture of α and γ polymorphic forms. IDM obtained by the two other methods remained in the γ form and a different attitude to the crystallinity decrease were observed, with a more considerable decrease in crystalline degree for IDM milled for 40 min in the presence of liquid nitrogen. The intrinsic dissolution rate (IDR) revealed a higher dissolution rate for Batches A and C-40-N, due to the higher IDR of α form than γ form for the Batch A, and the lower crystallinity degree for both the Batches A and C-40-N. These factors, as well as the decrease in particle size, influenced the IDM dissolution rate from the particle samples. Modifications in the solid physical state that may occur using different particle size reduction treatments have to be taken into consideration during the scale up and industrial development of new solid dosage forms.

  1. Preparing laboratory and real-world EEG data for large-scale analysis: A containerized approach

    Directory of Open Access Journals (Sweden)

    Nima eBigdely-Shamlo

    2016-03-01

    Full Text Available Large-scale analysis of EEG and other physiological measures promises new insights into brain processes and more accurate and robust brain-computer interface (BCI models.. However, the absence of standard-ized vocabularies for annotating events in a machine understandable manner, the welter of collection-specific data organizations, the diffi-culty in moving data across processing platforms, and the unavailability of agreed-upon standards for preprocessing have prevented large-scale analyses of EEG. Here we describe a containerized approach and freely available tools we have developed to facilitate the process of an-notating, packaging, and preprocessing EEG data collections to enable data sharing, archiving, large-scale machine learning/data mining and (meta-analysis. The EEG Study Schema (ESS comprises three data Levels, each with its own XML-document schema and file/folder convention, plus a standardized (PREP pipeline to move raw (Data Level 1 data to a basic preprocessed state (Data Level 2 suitable for application of a large class of EEG analysis methods. Researchers can ship a study as a single unit and operate on its data using a standardized interface. ESS does not require a central database and provides all the metadata data necessary to execute a wide variety of EEG processing pipelines. The primary focus of ESS is automated in-depth analysis and meta-analysis EEG studies. However, ESS can also encapsulate meta-information for the other modalities such as eye tracking, that are in-creasingly used in both laboratory and real-world neuroimaging. ESS schema and tools are freely available at eegstudy.org, and a central cata-log of over 850 GB of existing data in ESS format is available at study-catalog.org. These tools and resources are part of a larger effort to ena-ble data sharing at sufficient scale for researchers to engage in truly large-scale EEG analysis and data mining (BigEEG.org.

  2. Use of large-scale chromatography in the preparation of armodafinil.

    Science.gov (United States)

    Hauck, Willy; Adam, Philippe; Bobier, Christelle; Landmesser, Nelson

    2008-08-01

    Armodafinil, the (R)-enantiomer of modafinil, is a medication used to treat the excessive sleepiness associated with narcolepsy, obstructive sleep apnea/hypopnea syndrome, and shift work sleep disorder. We report here the chemical development of armodafinil and the investigations that led to a commercial route to prepare this pure enantiomer. Three synthetic approaches were used to provide the chiral sulfoxide. Resolution via preferential crystallization was used for phase I clinical trials and was subsequently replaced by chiral chromatography, enabling us to pursue a rapid filing and registration of the API. Finally, the commercial route was developed and employed asymmetric oxidation catalyzed by a titanium(IV) isopropoxide and diethyl tartrate system. The advantages of choosing a chromatographic development pathway to expedite registration while concurrently developing an economical chiral synthesis route is discussed in the context of armodafinil development.

  3. Preparative Scale MS-Guided Isolation of Bioactive Compounds Using High-Resolution Flash Chromatography: Antifungals from Chiloscyphus polyanthos as a Case Study.

    Science.gov (United States)

    Azzollini, Antonio; Favre-Godal, Quentin; Zhang, Jiaozhen; Marcourt, Laurence; Ebrahimi, Samad Nejad; Wang, Shuqi; Fan, Peihong; Lou, Hongxiang; Guillarme, Davy; Queiroz, Emerson Ferreira; Wolfender, Jean-Luc

    2016-07-01

    In natural product research, the efficient purification of molecules from large amounts of complex extracts is a key element. In this regard, an integrative strategy for efficient MS-guided isolation of antifungal compounds has been developed. First, off-line HPLC antifungal activity-based profiling and HPLC-PDA-MS profiling were used to localize the compounds of interest on the analytical scale. Then, the analytical gradient was geometrically transferred to the flash chromatographic level. Finally, an MS-triggered isolation of the localized bioactive molecules was realized using high-resolution flash chromatographic columns (15 µm spherical particles) coupled to a single quadrupole mass spectrometer via a splitter system. This isolation strategy was applied for the MS-targeted purification of antifungal principles from the liverwort Chiloscyphus polyanthos. This rational methodology has high potential for the targeted large-scale purification of bioactive compounds, avoiding the need to repeat a given bioassay at each isolation step. Seven sesquiterpene lactones were isolated, of which five were found to be bioactive and one was reported as a new compound. The absolute configuration of some compounds was established for the first time by electronic circular dichroism spectroscopy.

  4. Preparation of glibenclamide nanocrystals by a simple laboratory scale ultra cryo-milling

    Energy Technology Data Exchange (ETDEWEB)

    Martena, Valentina; Censi, Roberta [University of Camerino, School of Pharmacy (Italy); Hoti, Ela; Malaj, Ledjan [University of Tirana, Department of Pharmacy (Albania); Martino, Piera Di, E-mail: piera.dimartino@unicam.it [University of Camerino, School of Pharmacy (Italy)

    2013-06-15

    The objective of this study is to evaluate the ability to reduce the particle size of glibenclamide (GBC) to the nanometric scale through a very simple and well-known laboratory scale method, the laboratory scale ultra cryo-milling. The effect of milling on GBC crystalline properties and dissolution behaviour was deliberately evaluated in the absence of any surfactants as stabilizers. The milling procedure consisted in adding particles to liquid nitrogen and milling them by hand in a mortar with a pestle for different time intervals (15, 30, 40 min). For comparison, the same milling procedure was also applied without liquid nitrogen. The particle size reduction was evaluated for the coarsest samples (>3 {mu}m) by measuring the particle Ferret's diameter through scanning electron microscopy, while for the smallest one (<3 {mu}m) by dynamic light scattering. A time grinding of 40 min in the presence of liquid nitrogen was revealed highly efficacious to obtain particles of nanodimensions, with a geometric mean particle size of 0.55 {+-} 0.23 {mu}m and more than the 80 % of particles lower than 1,000 nm. Interestingly, non-agglomerated particles were obtained. Differential scanning calorimetry and X-ray powder diffractometry allowed to assess that under mechanical treatment no polymorphic transitions were observed, while a decrease in crystallinity degree occurred depending on the milling procedure (presence or absence of liquid nitrogen) and the milling time (crystallinity decreases at increasing milling time from 15 to 40 min). A comparison of the intrinsic dissolution rate and the dissolution from particles revealed an interesting improvement of particle dissolution particularly for particles milled in the presence of liquid nitrogen due to an increase in particle surface area and concentration gradient, according to the Noyes-Whitney equation.

  5. Rapid and Small Scale Isolation of the Toxins from Guangxi King Cobra (Ophiophagus hannah) Venom Using Ion-Exchange HPLC%普通离子交换剂用于HPLC柱层析法快速分离眼镜王蛇毒

    Institute of Scientific and Technical Information of China (English)

    李其斌; 莫武宁; 黄光武; 金城记代彦; 中村真理子; 小杉忠诚

    2002-01-01

    For rapid isolation and analysis of the toxic factors in the venom of king cobra (Ophiophagus hannah, Oh ) We used the technique of high pressure liquid chromatography (HPLC) with an ion-exchange column of TSKgel SP-Toyopearl 650 Superfine (4 × 150 mm) The better isolating conditions of absorbence, elution buffer (pH, solute ionic strength), gradient schedule and flow rate were examined and determined. The absorbence at wavelength of 230 nm was the best condition for determine the concentration proteins of Oh. venom in ammonium acetate buffer. On ion-exch age HPLC, proteins in Oh. venom were separated in a gradient manner from 20 mM to 0. 2 M (and pH, from 5.8 to 8.0) at a flow rate of 0. 3 ml/min at room temperature (25℃) . After the crude venom was injected to HPLC, 16 peaks of proteins were obtained. On the analysis of the separated peak using reverse-phase HPLC on a Cosmosil 5C4-AR-300 (4.6 mm × 150 mm) column, 5 peaks among them were shown as a single peak. Gel permeation HPLC on a TSKgel Toyopearl HW-40 Fine column was used for further purification of the fractions which had not shown as a single peak on reverse-phage HPLC, and another five fractions of a single protein were obtained. The results showed this ion-exchange column could be valuable for rapid fractionation of Oh. venom, especially in a small scale. The gel permeation HPLC also could be useful for further purifying the complex fractions which could not be separated by ion-exchange HPLC.%目的为了经济快速分离眼镜王蛇(Ophiophagus hannah,Oh)蛇毒中的毒素成分.方法用普通离子交换剂于高效液相色谱柱(HPLC)TSKgel SP-Toyopearl 650 SF(4×150mm)层析法,实验取得最佳分离条件后,将蛇毒样品上柱后进行梯度洗脱,各洗脱峰收集后在Cosmosil 5C4-AR-300柱(4.6×150mm)上进行逆相HPLC分析.非单峰组分再进行HPLC凝胶过滤柱TSKgelToyopearl HW-40 Fine(4×250mm)层析,层析峰组分再进行HPLC逆相分析.结果眼镜王蛇毒经HPLC

  6. Preparation of biomimetic nano-structured films with multi-scale roughness

    Science.gov (United States)

    Shelemin, A.; Nikitin, D.; Choukourov, A.; Kylián, O.; Kousal, J.; Khalakhan, I.; Melnichuk, I.; Slavínská, D.; Biederman, H.

    2016-06-01

    Biomimetic nano-structured films are valuable materials in various applications. In this study we introduce a fully vacuum-based approach for fabrication of such films. The method combines deposition of nanoparticles (NPs) by gas aggregation source and deposition of overcoat thin film that fixes the nanoparticles on a surface. This leads to the formation of nanorough surfaces which, depending on the chemical nature of the overcoat, may range from superhydrophilic to superhydrophobic. In addition, it is shown that by proper adjustment of the amount of NPs it is possible to tailor adhesive force on superhydrophobic surfaces. Finally, the possibility to produce NPs in a wide range of their size (45-240 nm in this study) makes it possible to produce surfaces not only with single scale roughness, but also with bi-modal or even multi-modal character. Such surfaces were found to be superhydrophobic with negligible water contact angle hysteresis and hence truly slippery.

  7. 磷酸可待因与布洛芬的分离与检测%RP-HPLC DETERMINATION FOR PAIN RELEASE COMPOUND PREPARATION OF CODEINE PHOSPHATE AND IBUPROFEN TABLET

    Institute of Scientific and Technical Information of China (English)

    南楠; 杨信群; 朱霁虹

    1998-01-01

    本文介绍了一种用高效液相色谱法(HPLC)检测复方制剂中磷酸可待因和布洛芬含量的方法.该方法用C18ODS为固定相,甲醇-0.05 mol·L-1KH2PO4(用三乙胺调pH=6)-THF(V/V=160:100:10)为流动相.UV检测波长254 nm.该方法不需经提取分离,溶解后直接进样.简便快速,结果可靠.

  8. Isolation of Components with Anti-angiogenesis Activity from Albizia julibrissin by Solid Phase Extraction Coupled with Preparative HPLC%SPE-HPLC法分离合欢皮中抗血管新生的活性组分

    Institute of Scientific and Technical Information of China (English)

    蔡维维; 施建军; 冯磊; 杜斌; 邱丽颖

    2014-01-01

    应用固相萃取-高效液相色谱法(SPE-HPLC),从合欢皮乙醇提取物-正丁醇相中分离得到若干个组分,再用HMEC-1细胞活性检测以及HPLC分析鉴定,筛选得到具有较高抑制新生血管活性的组分Ⅱ-4(IC50=1.45+0.11 μg/mL),且组成较简单.本法简单快速,可以为中药材有效组分的快速分离提供新的方法,也为后续进一步分离得到细胞活性有效单体化合物提供组成比较简单的合欢皮活性组分提取物.

  9. Simple and large scale refluxing method for preparation of Ce-doped ZnO nanostructures as highly efficient photocatalyst

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, M. [Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil (Iran, Islamic Republic of); Habibi-Yangjeh, A., E-mail: ahabibi@uma.ac.ir [Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil (Iran, Islamic Republic of)

    2013-01-15

    Graphical abstract: A simple method was applied for the preparation of Ce-doped ZnO nanostructures (mole fractions of Ce{sup 4+} ions are 0, 0.025, 0.05, 0.075 and 0.10) in water by refluxing for 3 h about at 90 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer A simple refluxing method was applied for preparation of Ce-doped ZnO nanostructures. Black-Right-Pointing-Pointer The XRD patterns demonstrate that loading of Ce{sup 4+} ions does not change the structure of ZnO. Black-Right-Pointing-Pointer The results indicate that the nanostructures with 0.05 mole fraction of Ce{sup 4+} ions exhibit highest photocatalytic activity. Black-Right-Pointing-Pointer The nanostructures have highest photocatalytic activity at solutions with pH between 5.4 and 9. - Abstract: A simple method was applied for preparation of Ce-doped ZnO nanostructures (mole fractions of Ce{sup 4+} ions are 0, 0.025, 0.05, 0.075 and 0.10) in water by refluxing for 3 h about at 90 Degree-Sign C. This method is large scale, mild and involve no templates, surfactants or additives. The prepared nanostructures were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-vis diffuse reflectance spectroscopy (DRS) techniques. The XRD patterns demonstrate that the nanostructures have the same crystal structure, and loading of Ce{sup 4+} ions does not change the structure of ZnO. The SEM images show that with increasing mole fraction of Ce{sup 4+} ions, morphology of the nanostructures changes from nanoplates to nanospheres. Photocatalytic activity of the nanostructures toward photodegradation of methylene blue (MB) was evaluated under UV irradiation. The results indicate that the nanostructures with 0.05 mole fraction of Ce{sup 4+} ions exhibit highest photocatalytic activity among the prepared samples. The influence of various operational parameters such as refluxing time, catalyst weight, calcinations temperature and pH of solution on the photodegradation reaction

  10. Calibration and scaling of GRACE, GOCO03S and classical hydrosphere models for further model combination preparation

    Science.gov (United States)

    Birylo, Monika; Kuczynska-Siehien, Joanna

    2014-05-01

    Equivalent water thickness (EWT) observation is a crucial part of a water cycle monitoring. A phenomenon which is going to be analyzed is an elementary natural issue. Monitoring and understanding of the water cycle phenomenon is an important part of economy, can provide a possibility of drought and flood prediction, atmosphere monitoring, river state, storage of drink water. Evaluating a method of a modern, effective and accurate water cycle monitoring will give an opportunity to prevent many disasters. Authors will test a new hydrosphere model that will be a combination of gradiometric and classical hydrosphere models. A sample area will be a territory of Poland, but an idea is to evaluate a method that can be used globally. Two satellite models will give a modern, almost in real-time presentation, while classical models will give details. The aim of the paper is to calibrate and scale to the same level all mentioned models as a basis for further model combination preparation.

  11. Large-scale preparation of active caspase-3 in E. coli by designing its thrombin-activatable precursors

    Directory of Open Access Journals (Sweden)

    Park Sung

    2008-12-01

    Full Text Available Abstract Background Caspase-3, a principal apoptotic effector that cleaves the majority of cellular substrates, is an important medicinal target for the treatment of cancers and neurodegenerative diseases. Large amounts of the protein are required for drug discovery research. However, previous efforts to express the full-length caspase-3 gene in E. coli have been unsuccessful. Results Overproducers of thrombin-activatable full-length caspase-3 precursors were prepared by engineering the auto-activation sites of caspase-3 precursor into a sequence susceptible to thrombin hydrolysis. The engineered precursors were highly expressed as soluble proteins in E. coli and easily purified by affinity chromatography, to levels of 10–15 mg from 1 L of E. coli culture, and readily activated by thrombin digestion. Kinetic evaluation disclosed that thrombin digestion enhanced catalytic activity (kcat/KM of the precursor proteins by two orders of magnitude. Conclusion A novel method for a large-scale preparation of active caspase-3 was developed by a strategic engineering to lack auto-activation during expression with amino acid sequences susceptible to thrombin, facilitating high-level expression in E. coli. The precursor protein was easily purified and activated through specific cleavage at the engineered sites by thrombin, generating active caspase-3 in high yields.

  12. HPLC determination of substance and related substances for the preparation of ibuprofen%HPLC法测定布洛芬原料及制剂的有关物质

    Institute of Scientific and Technical Information of China (English)

    刘芳; 柳小秦; 徐长根; 孟新芳

    2011-01-01

    Objective : To perfect the determination method of the related substances in ibuprofen, for its adaptability to our country. Methods: Three related substances of' ibuprofen are determinated by HPLC. Waters Symmetry ShieldTM C18 (4. 6 mm × 250 mm,5 μm) was used with mobile phase consisted of acetonitrile - water ( adjusted pH to 3. 0 with phosphoric acid) (1: 1). The detective wavelength was set at 254 nm. Results : In the determination of related substances by HPLC,the linearity were good within the range 2 - 50 μg · mL -1 , and the regression coefficient were 0. 9999 , 1. 0000 ,0. 9999 , respectively , while the recoveries were 99. 7% ,99. 5 % , 100. 1% , respectively.Conclusion: This method is operated easily, and it can be used to accurately determinate the related substances contend in ibuprofen.%目的:为了完善布洛芬的有关物质检查方法,使其更适用于中国的实际生产情况.方法:采用高效液相色谱法,紫外检测器,十八烷基硅烷键合硅胶柱,固定相:phenomenex C18(4.6mmx250mm,5μm),流动相:乙腈-水(用磷酸调节pH为3.0)(1:1),检测波长:254nm.结果:3种已知杂质和布洛芬及其他未知杂质均能得到有效分离;;3种已知杂质在2-50μg·ML-1范围内线性关系良好,r分别为0.9999,1.0000,0.9999,平均回收率分别为99.7%,99.5%,100.1%.结论:本方法灵敏、准确、可靠,能够准确测定布洛芬原料及制剂的有关物质.

  13. RP-HPLC Determination of vitamins B1, B3, B6, folic acid and B12 in multivitamin tablets

    OpenAIRE

    2005-01-01

    Abstract:Asimple and sensitive reversed-phase, ion-pair HPLC method was developed and validated for the simultaneous determination of B-group vitamins, thiamine chloride hydrochloride (B1), nicotinamide (B3), pyridoxine hydrochloride (B6) and folic acid in Pentovit® coated tablets. The cyanocobalamine (B12) was determined separately, because of its low concentration in the investigated multivitamin preparation. RP-HPLC analysis was performed with a LKB 2150 HPLC system, equipped with a UV/VI...

  14. Studium problematiky stability léčivých přípravků metodou HPLC

    OpenAIRE

    Havlíková, Lucie

    2006-01-01

    "Problems of Stability Testing of the Active Substances and Pharmaceutical Preparations Using HPLC" The presented thesis deals with using of high performance liquid chromatography for the analysis of pharmaceutical active substance, its degradation products, and impurities in pharmaceutical preparations. The theoretical part describes in a more detailed way the topic stability and impurity testing in pharmaceutical preparations. The HPLC theory, method optimization, isolation procedures, meth...

  15. A fast and sensitive HPLC method for sulfite analysis in food based on a plant sulfite oxidase biosensor.

    Science.gov (United States)

    Theisen, S; Hänsch, R; Kothe, L; Leist, U; Galensa, R

    2010-09-15

    A reliable and sensitive analysis of sulfites in food is essential in food monitoring. However, the established methods exhibit deficiencies in the very low concentration ranges (below 10 mg/L SO(2)), especially with more complex food matrices. With a focus on these challenges, an HPLC method with immobilized enzyme reactor (HPLC-IMER) for the analysis of sulfites in food was optimized and compared to a standard method. A modulated sample preparation procedure and the use of a novel sulfite oxidase from Arabidopsis thaliana were explored to make the method applicable for most food samples. The plant sulfite oxidase turned out to be superior to the commercially available animal sulfite oxidase in terms of detection limit (0.01 mg/L SO(2)), linear range (0.04-20 mg/L SO(2)) and stability. In a small scale comparison within our laboratory, as well as in a standardized proficiency testing, the HPLC-IMER was compared to an established distillative method. The enzyme-based method is not only more sensitive and specific, it also yields higher sulfite recoveries in almost all samples while exhibiting better statistic method parameters. Copyright 2010 Elsevier B.V. All rights reserved.

  16. 用加速溶剂萃取及制备型高效液相色谱法从烟梗中制取多酚对照品%Preparation of Polyphenol Reference Substance from Peduncle of Tobacco by Accelerated Solvent Extraction and Pre-HPLC

    Institute of Scientific and Technical Information of China (English)

    金诚; 刘汗青; 田孟华; 曹鑫

    2013-01-01

    提出用加速溶剂萃取及制备型高效液相色谱方法从烟梗中提取、制备多酚对照品的方法.样品粉碎后以乙醇(80+-20)溶液为萃取溶剂经加速溶剂萃取仪在110℃静态萃取10 min,提取液氮气吹扫60 s后过MCI树脂和Sephadex LH 20凝胶净化,流出液用丙酮定容后,先通过制备型高效液相色谱初步分离,再通过半制备高效液相色谱进一步分离,得到5个多酚类化合物,经核磁共振波谱法鉴定分别为芸香苷、绿原酸、槲皮素、柚皮素和咖啡酸甲酯.5个多酚类化合物的纯度均大于99%,故可用作多酚对照品.%A method for the extraction and preparation of polyphenol reference substances from peduncle of tobacco by accelerated solvent extraction and pre-HPLC was proposed.The sample was crushed and extracted with ethanol (80+-20) solution under static condition at 110 C for 10 min,and the extract was swept for 60 s by N2-blowing and purified by MCI resin and Sephadex LH 20 gel.The eluate collected was taken up with acetone and used for preliminary separation by pre-HPLC,and for further separation by semi Pre-HPLC,and five polyphenols were obtained,which were identified by NMR to be rutin,chlorogenic acid,quercetin,naringenin and methyl caffeate.The purity of the 5 polyphenols were more than 99%,which could be used as reference materials.

  17. Efficient separation of curcumin, demethoxycurcumin, and bisdemethoxycurcumin from turmeric using supercritical fluid chromatography: From analytical to preparative scale.

    Science.gov (United States)

    Song, Wei; Qiao, Xue; Liang, Wen-fei; Ji, Shuai; Yang, Lu; Wang, Yuan; Xu, Yong-wei; Yang, Ying; Guo, De-an; Ye, Min

    2015-10-01

    Curcumin is the major constituent of turmeric (Curcuma longa L.). It has attracted widespread attention for its anticancer and anti-inflammatory activities. The separation of curcumin and its two close analogs, demethoxycurcumin and bisdemethoxycurcumin, has been challenging by conventional techniques. In this study, an environmentally friendly method based on supercritical fluid chromatography was established for the rapid and facile separation of the three curcuminoids directly from the methanol extract of turmeric. The method was first developed and optimized by ultra performance convergence chromatography, and was then scaled up to preparative supercritical fluid chromatography. Eluted with supercritical fluid CO2 containing 8-15% methanol (containing 10 mM oxalic acid) at a flow rate of 80 mL/min, curcumin, demethoxycurcumin and bisdemethoxycurcumin could be well separated on a Viridis BEH OBD column (Waters, 250 mm × 19 mm, 5 μm) within 6.5 min. As a result, 20.8 mg of curcumin (97.9% purity), 7.0 mg of demethoxycurcumin (91.1%), and 4.6 mg of bisdemethoxycurcumin (94.8%) were obtained after a single step of supercritical fluid chromatography separation with a mean recovery of 76.6%. Showing obvious advantages in low solvent consumption, large sample loading, and easy solvent removal, supercritical fluid chromatography was proved to be a superior technique for the efficient separation of natural products.

  18. HPLC-DAD determination of imidacloprid in onion

    OpenAIRE

    Mandić Aljoša; Lazić Sanja; Inđić Dušanka

    2003-01-01

    Imidacloprid is an insecticide most commonly used on vegetables, potato sugar beet, fruit, cereal, maize and rice. Imidacloprid residue has been determined in spiked onion and in onion samples. Sample preparation consisted of dichlormethane extraction of imidacloprid from onion, followed by purification of the obtained extract on a LC-Florisil disposable cartridge. The HPLC-DAD method bas been developed on reversed-phase for separation of imidacloprid with a mixture of 0.01 M phosphate buffer...

  19. Synthesis and Migratory-Insertion Reactivity of CpMo(CO)[subscript3](CH[subscript3]): Small-Scale Organometallic Preparations Utilizing Modern Glovebox Techniques

    Science.gov (United States)

    Whited, Matthew T.; Hofmeister, Gretchen E.

    2014-01-01

    Experiments are described for the reliable small-scale glovebox preparation of CpMo(CO)[subscript 3](CH[subscript 3]) and acetyl derivatives thereof through phosphine-induced migratory insertion. The robust syntheses introduce students to a variety of organometallic reaction mechanisms and glovebox techniques, and they are easily carried out…

  20. Physico-chemical characterization of human recombinant follicle-stimulating hormone (hFSH) and its subunits by reversed-phase high-performance liquid chromatography ( RP-HPLC): comparison with pituitary hFSH reference preparation from 'National Hormone and Pituitary Program' from USA; Caracterizacao fisico-quimica da foliculotropina humana(hFSH) recombinabte e de suas subunidades, por cromatografia liquida de alta eficiencia (HPLC) em fase reversa: comparacao com a preparacao de referencia de hFSH de origem hipofisaria do ''National Hormone and Pituitary Program'' dos EUA

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Renan Fernandes

    2006-07-01

    A reversed-phase high-performance liquid chromatography (RP-HPLC) method for the qualitative and quantitative analysis of intact human folliclestimulating hormone (hFSH) was established and validated for accuracy, precision and sensitivity. Human FSH is a dimeric glycoprotein hormone widely used as a diagnostic analyte and as therapeutic product in reproductive medicine. The technique developed preserves the protein integrity, allowing the analysis of the intact heterodimeric form rather than just of its subunits, as it is the case for the majority of the conditions currently employed. This methodology has also been employed for comparing the relative hydrophobicity of pituitary, urinary and two Chinese hamster ovary (CHO)-derived hFSH preparations, as well as of two other related glycoprotein hormones of the anterior pituitary: human thyroid-stimulating hormone (hTSH) and human luteinizing hormone (hLH). The least hydrophobic of the three glycohormones analyzed was hFSH, followed by hTSH and hLH. A significant difference (p<0.005) was observed in t{sub R} between the pituitary and recombinant hFSH preparations, reflecting structural differences in their carbohydrate moieties. Two main isoforms were detected in urinary hFSH, including a form which was significantly different (p<0.005) for the pituitary and recombinant preparations. The linearity of the dose-response curve (r = 0.9965, n = 15) for this RP-HPLC methodology, as well as an inter-assay precision with relative standard deviation less than 4% for the quantification of different hFSH preparations and a sensitivity of the order of 40 ng, were demonstrated. The chromatographic behavior and relative hydrophobicity of the individual subunits of the pituitary and recombinant preparations were also analyzed. Furthermore, the accurate molecular mass of the individual hFSH subunits and of the heterodimer were simultaneously determined by matrix-assisted laser desorption ionization time-of-flight mass spectral

  1. HPLC-MS法表征坝漆酚类化合物的结构%Identification of Chemical Structure of Urushiol from Maoba Lacquer by HPLC-MS

    Institute of Scientific and Technical Information of China (English)

    何源峰; 王成章; 陆榕

    2012-01-01

    Middle pressure chromatography was used to purify urushiol. Its purity reached above 90%. HPLC, HPLC-MS, MS was applied to analyze urushiol that was extracted from Maoba lacquer. HPLC was performed under a methanol-water system (volume ratio) with a flow rate of 1mL/min. Eighteen peaks appeared under UV detector of 210 nm. Thirteen compounds were separated by HPLC-MS, mainly contained C15/17 with different degrees of unsaturation. The middle pressure chromatography and HPLC could be used as a efficient preparation and analysis method.%应用中低压柱分离毛坝漆酚类化合物,漆酚质量分数90%以上.应用HPLC、HPLC-MS、MS分析表征毛坝漆漆酚化学结构,HPLC以甲醇-水体积比9∶1为流动相,总流速1 mL/min,UV 210 nm能够分离18个酚类化合物,HPLC-MS表征13个酚类化合物,主要为C15不饱和三烯漆酚和C17不同饱和度的漆酚.漆酚的中低压柱分离及HPLC跟踪为漆酚提供了快速分离方法.

  2. Large-scale preparation of clove essential oil and eugenol-loaded liposomes using a membrane contactor and a pilot plant.

    Science.gov (United States)

    Sebaaly, Carine; Greige-Gerges, Hélène; Agusti, Géraldine; Fessi, Hatem; Charcosset, Catherine

    2016-01-01

    Based on our previous study where optimal conditions were defined to encapsulate clove essential oil (CEO) into liposomes at laboratory scale, we scaled-up the preparation of CEO and eugenol (Eug)-loaded liposomes using a membrane contactor (600 mL) and a pilot plant (3 L) based on the principle of ethanol injection method, both equipped with a Shirasu Porous Glass membrane for injection of the organic phase into the aqueous phase. Homogenous, stable, nanometric-sized and multilamellar liposomes with high phospholipid, Eug loading rates and encapsulation efficiency of CEO components were obtained. Saturation of phospholipids and drug concentration in the organic phase may control the liposome stability. Liposomes loaded with other hydrophobic volatile compounds could be prepared at large scale using the ethanol injection method and a membrane for injection.

  3. Extraction and Quantitative HPLC Analysis of Coumarin in Hydroalcoholic Extracts of Mikania glomerata Spreng: ("guaco" Leaves

    Directory of Open Access Journals (Sweden)

    Celeghini Renata M. S.

    2001-01-01

    Full Text Available Methods for preparation of hydroalcoholic extracts of "guaco" (Mikania glomerata Spreng. leaves were compared: maceration, maceration under sonication, infusion and supercritical fluid extraction. Evaluation of these methods showed that maceration under sonication had the best results, when considering the ratio extraction yield/extraction time. A high performance liquid chromatography (HPLC procedure for the determination of coumarin in these hydroalcoholic extracts of "guaco" leaves is described. The HPLC method is shown to be sensitive and reproducible.

  4. Preparation, Study and Modification of Nanometer-Scale Flat TiO2 Surfaces by Electrochemistry and AFM Techniques

    DEFF Research Database (Denmark)

    Dihn Thi, M. T.; Cleemann, Lars Nilausen; Welinder, Anne Christina

    In order to study local properties of surfaces, it is necessary to control their preparation mode to get reproducible and well characterized samples. The first part of this work concerns the preparation of TiO2 films on Ti substrates that fulfil these criteria. The TiO2 formed by anodisation...... to the preparation and the study of TiO2/Ti electrodes “modified” by a Pt-deposit....

  5. Two-step preparation of nano-scaled magnetic chitosan particles using Triton X-100 reversed-phase water-in-oil microemulsion system

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhengkun; Jiang, Feihong [College of Food Science and Engineering, Northwest A and F University, Yangling, Shaanxi 712100 (China); Lee, Tung-Ching, E-mail: lee@aesop.rutgers.edu [Department of Food Science, Rutgers, the State University of New Jersey, 65 Dudley Road, New Brunswick, NJ 08901 (United States); Yue, Tianli, E-mail: yuetl305@nwsuaf.edu.cn [College of Food Science and Engineering, Northwest A and F University, Yangling, Shaanxi 712100 (China)

    2013-12-25

    Highlights: •A new two-step route for nano-scaled magnetic chitosan particles preparation. •Triton X-100 reversed-phase microemulsion system was used for chitosan coating. •Narrow size distribution of magnetic chitosan nanoparticles was achieved. •Quantitative evaluation of recoverability for the magnetic chitosan nanoparticles. -- Abstract: A new two-step route for the preparation of nano-scaled magnetic chitosan particles has been developed, different from reported one-step in situ preparation and two-step preparation method of reversed-phase suspension, Triton X-100 reversed-phase water-in-oil microemulsion encapsulation method was employed in coating the pre-prepared Fe{sub 3}O{sub 4} nanoparticles with chitosan. The resultant magnetic chitosan particles owned a narrow size distribution ranging from 50 to 92 nm. X-ray diffraction patterns (XRD) indicated that the chitosan coating procedure did not change the spinal structure of Fe{sub 3}O{sub 4} magnetic nanoparticles. The results of Fourier transform infrared (FTIR) analysis and thermogravimetric analysis (TGA) demonstrated that the chitosan was coated on Fe{sub 3}O{sub 4} nanoparticles and its average mass content was ∼50%. The saturated magnetization of the magnetic Fe{sub 3}O{sub 4}/chitosan nanoparticles reached 18.62 emu/g, meanwhile, the nanoparticles showed the characteristics of superparamagnetism. The magnetic chitosan nanoparticles showed a high recoverability of 99.99% in 10 min when pH exceeded 4. The results suggested that the as-prepared magnetic chitosan particles were nano-scaled with a narrow size distribution and a high recoverability.

  6. HPLC Determination of Piperine in Mongolian Medicine Preparation Hao Sen Bu Ru-13%高效液相色谱法测定蒙药制剂浩森布如-13中胡椒碱的含量

    Institute of Scientific and Technical Information of China (English)

    张海涛; 吕颖; 齐向群; 李旻辉

    2016-01-01

    目的:建立高效液相色谱法测定蒙药制剂浩森布如-13中胡椒碱的含量。方法:采用DiamonsiL C18(250mm×4.6mm,5μm)色谱柱;以甲醇-水(77∶23)为流动相;流速1.0mL·min-1;检测波长343nm;柱温为30℃。结果:胡椒碱在4~40μg·mL-1(r=0.9999)范围内线性关系良好;平均回收率为98.19%(n=9),RSD为0.86%。结论:本方法简便准确、稳定可靠,可用于蒙药制剂浩森布如-13的胡椒碱含量测定。%Objective:To establish a method for the determination of piperine in mongolian medicine preparation Haosenburu-13. Methods:A DiamonsiL-C18 (250mm×4.6mm, 5μm) column was used with the mobile phase being chromatographic methanol-water (77∶23), flow rate being 1.0mL·min-1,detecting wavelength being 343nm, the column temperature being 30℃. Results:The linear response range from 4~40μg·mL-1 (r=0.9999,n=6)of piperine;the average recoveries (n=9)of the method was 98.19% with RSD 0.86%. Conclusion:The method is simple,accurate,reproducible and stable,and can be used for the quality control of mongolian medicine preparation Hao Sen Bu Ru-13.

  7. Preparation, Study and Modification of Nanometer-Scale Flat TiO2 Surfaces by Electrochemistry and AFM Techniques

    DEFF Research Database (Denmark)

    Dihn Thi, M. T.; Cleemann, Lars Nilausen; Welinder, Anne Christina

    In order to study local properties of surfaces, it is necessary to control their preparation mode to get reproducible and well characterized samples. The first part of this work concerns the preparation of TiO2 films on Ti substrates that fulfil these criteria. The TiO2 formed by anodisation of t...

  8. Acquisition of Preparative Gel Permeation Chromatography for Research and Education in Energy Conversion and Nanocomposites

    Science.gov (United States)

    2017-04-19

    materials for energy. The pGPC acquired from SHIMADZU SCIENTIFIC INSTRUMENTS is equipped with one LC-20AR HPLC Pump (MAX flow rate 20ml/min), one...SIL-20A Prominence HPLC Autosampler (high-speed accurate injection of samples), one CBM-20A HPLC System Controller, one CTO-20A Prominence HPLC ...Column Ovens (large capacity, temperature up to 85 o C), one RID-20A Refractive Index Detector, two Shodex HPLC Preparatory Scale Column (KF-2004), one

  9. Preparation of drug-in-cyclodextrin-in-liposomes at a large scale using a membrane contactor: Application to trans-anethole.

    Science.gov (United States)

    Gharib, Riham; Greige-Gerges, Hélène; Jraij, Alia; Auezova, Lizette; Charcosset, Catherine

    2016-12-10

    The present study aimed to prepare liposomes loaded with cyclodextrin/drug inclusion complexes at a pilot scale based on the ethanol injection technique. Anethole (ANE), a major component of anise and fennel essential oils, was used as a model of a volatile and highly hydrophobic drug. Membrane contactor (600mL) and a pilot plant (3L) were used for liposome production. The liposome preparations obtained were characterized for size, polydispersity index, zeta potential, morphology, stability and ANE release rate. All experimental set-ups were shown to be appropriate for the preparation of small, multilamellar vesicles with narrow size distribution and good stability at 4°C. The drug release study showed that only a small amount of ANE was released from liposome formulations after 21days of storage at 4°C. The loading rate of ANE was higher when ethanol was evaporated directly on the pilot plant compared to a rotary evaporation.

  10. HPLC-NMR revisited: Using time-slice HPLC-SPE-NMR with database assisted dereplication

    DEFF Research Database (Denmark)

    Johansen, Kenneth; Wubshet, Sileshi Gizachew; Nyberg, Nils

    2013-01-01

    Time based trapping of chromatographically separated compounds on to solid-phase extraction cartridges (SPE) and subsequent elution to NMR-tubes was done to emulate the function of HPLC–NMR for dereplication purposes. Sufficient mass sensitivity was obtained by the use of a state-of-the-art HPLC......–SPE–NMR-system with a cryogenically cooled probe head, designed for 1.7 mm NMR-tubes. The resulting 1H NMR spectra (600 MHz) were evaluated against a database of previously acquired and prepared spectra. The in-house developed matching algorithm, based on partitioning of the spectra and allowing for changes in the chemical shifts...... and analogues. The database matching of the resulting spectra positively identified expected compounds, while the number of false positives was few and easily recognized....

  11. Scale-up from shake flasks to pilot-scale production of the plant growth-promoting bacterium Azospirillum brasilense for preparing a liquid inoculant formulation.

    Science.gov (United States)

    Trujillo-Roldán, Mauricio A; Valdez-Cruz, Norma A; Gonzalez-Monterrubio, César F; Acevedo-Sánchez, Eduardo V; Martínez-Salinas, Carlos; García-Cabrera, Ramsés I; Gamboa-Suasnavart, Ramsés A; Marín-Palacio, Luz D; Villegas, Jesús; Blancas-Cabrera, Abel

    2013-11-01

    Azospirillum brasilense has industrial significance as a growth promoter in plants of commercial interest. However, there is no report in the literature disclosing a liquid product produced in pilot-scale bioreactors and is able to be stored at room temperature for more than 2 years. The aim of this work was to scale up a process from a shake flask to a 10-L lab-scale and 1,000-L pilot-scale bioreactor for the production of plant growth-promoting bacterium A. brasilense for a liquid inoculant formulation. Furthermore, this work aimed to determine the shelf life of the liquid formulation stored at room temperature and to increase maize crops yield in greenhouses. Under a constant oxygen mass transfer coefficient (K L a), a fermentation process was successfully scaled up from shake flasks to 10- and 1,000-L bioreactors. A concentration ranging from 3.5 to 7.5 × 10(8) CFU/mL was obtained in shake flasks and bioreactors, and after 2 years stored at room temperature, the liquid formulation showed one order of magnitude decrease. Applications of the cultured bacteria in maize yields resulted in increases of up to 95 % in corncobs and 70 % in aboveground biomass.

  12. Preparation of Calibration Standards of N1-H Paralytic Shellfish Toxin Analogues by Large-Scale Culture of Cyanobacterium Anabaena circinalis (TA04

    Directory of Open Access Journals (Sweden)

    Toshiyuki Suzuki

    2011-03-01

    Full Text Available Mouse bioassay is the official testing method to quantify paralytic shellfish toxins (PSTs in bivalves. A number of alternative analytical methods have been reported. Some methods have been evaluated by a single laboratory validation. Among the different types of methods, chemical analyses are capable of identifying and quantifying the toxins, however a shortage of the necessary calibration standards hampers implementation of the chemical analyses in routine monitoring of PSTs in bivalves. In our present study, we studied preparation of major PST analogues as calibrants by large-scale cultivation of toxic freshwater cyanobacteria Anabaena circinalis TA04. The cells were steadily grown in 10 L bottle for 28 days. The primary N1-H toxins, C1/C2, were produced at a concentration of 1.3 ± 0.1 µmol/L. The intracellular and extracellular toxins occupied 80% and 20%, respectively. Over 220 µmol of the toxins was obtained from approximately 200 L of the culture over six months, demonstrating that it is sufficient to prepare saxitoxin analogues. The toxins were chemically converted to six N1-H analogues. Preparation of the analogues was carried out at relatively high yields (50–90%. The results indicate that our preparation method is useful to produce N1-H toxins. In our present study, detailed conditions for preparation of one of the rare N1-H analogues, gonyautoxin-5, were investigated.

  13. Validation of the Newly Developed Graphical Inventory of Ethical Leadership (GIEL) Scale: Implications for Administrator Preparation and Business Leaders

    Science.gov (United States)

    Hanson, Janet; Loose, William; Reveles, Ursula; Hanshaw, George

    2017-01-01

    This quantitative pilot-study empirically tested the factor structure and reliability of the newly developed Graphical Inventory of Ethical Leadership (GIEL) scale, a Likert-style scale for quantifying key concepts related to ethical leadership. Correlations and principal components analyses were performed using pre-existing data as self-reports…

  14. Acquisition of HPLC-Mass Spectrometer

    Science.gov (United States)

    2015-08-18

    31-Jan-2015 Approved for Public Release; Distribution Unlimited Final Report: Acquisition of HPLC -Mass Spectrometer The views, opinions and/or findings...published in peer-reviewed journals: Final Report: Acquisition of HPLC -Mass Spectrometer Report Title The acquisition of the mass spectrometer has been a

  15. HPLC chromatofocusing of human immunoglobulins.

    Science.gov (United States)

    Waldrep, J C; Schulte, J R

    1989-03-31

    A method is described for fractionation and analysis of IgA, IgM, and IgG and antibodies in human serum and/or plasma using a combination of HPLC chromatofocusing and immunoassay. A pH 9.0-3.2 gradient is utilized to separate the major proteins in the complex biological samples and monoclonal antibody based ELISAs used to determine the isotype profiles. Antigen-specific ELISAs are subsequently utilized to determine the distribution of antibody species within the chromatofocused specimens. This method is versatile since multiple simultaneous assays can easily be run on each fraction generating extensive qualitative information regarding immunoglobulin classes, subclasses, and antibodies and their distribution profiles. Such spectra will prove useful for experimental kinetic analysis of the humoral immune status of humans and experimental animals.

  16. Preparation of a skin equivalent phantom with interior micron-scale vessel structures for optical imaging experiments.

    Science.gov (United States)

    Chen, Chen; Klämpfl, Florian; Knipfer, Christian; Riemann, Max; Kanawade, Rajesh; Stelzle, Florian; Schmidt, Michael

    2014-09-01

    A popular alternative of preparing multilayer or microfluidic chip based phantoms could have helped to simulate the subsurface vascular network, but brought inevitable problems. In this work, we describe the preparation method of a single layer skin equivalent tissue phantom containing interior vessel channels, which mimick the superficial microvascular structure. The fabrication method does not disturb the optical properties of the turbiding matrix material. The diameter of the channels reaches a value of 50 μm. The size, as well as the geometry of the generated vessel structures are investigated by using the SD-OCT system. Our preliminary results confirm that fabrication of such a phantom is achievable and reproducible. Prospectively, this phantom is used to calibrate the optical angiographic imaging approaches.

  17. Large scale preparation and application of bacteriocins%细菌素的制备及其应用

    Institute of Scientific and Technical Information of China (English)

    方佳琪; 别怀周; 陈晓琳; 张明

    2011-01-01

    In recent years, bacteriocins that can inhibit or kill the growth of some bacteria have a wide range of practical application in food preservation, disease treatment and many other related aspects were found, and the preparation methods of bacteriocin were widely reported. This article outlines the preparation methods of bacteriocins and its application in many fields.%近年来,具有抑菌活性的细菌素被发现在食品防腐保鲜、疾病治疗和其他许多相关方面有着广泛的应用价值,各种制备细菌素的方法 也被广泛报道.本文概述了细菌素的制备方法 以及其在诸多领域中的应用.

  18. Surfactant Removal Study for Nano-Scale SmCo5 Powder Prepared by High Energy Ball Milling (Postprint)

    Science.gov (United States)

    2014-04-01

    DD-MM-YY) 2. REPORT TYPE 3. DATES COVERED (From - To) April 2014 Interim 19 March 2014 – 31 March 2014 4. TITLE AND SUBTITLE SURFACTANT ...thickness of 300 nm were prepared by high energy ball milling using valeric acid as a surfactant . In order to remove the surfactant the as-milled...investigated. Partial (58%) and nearly complete (96%) surfactant removal was observed by DSC after treatments at 200°C and 400°C, respectively, without oxide

  19. Using HPLC-Mass Spectrometry to Teach Proteomics Concepts with Problem-Based Techniques

    Science.gov (United States)

    Short, Michael; Short, Anne; Vankempen, Rachel; Seymour, Michael; Burnatowska-Hledin, Maria

    2010-01-01

    Practical instruction of proteomics concepts was provided using high-performance liquid chromatography coupled with a mass selective detection system (HPLC-MS) for the analysis of simulated protein digests. The samples were prepared from selected dipeptides in order to facilitate the mass spectral identification. As part of the prelaboratory…

  20. Using HPLC-Mass Spectrometry to Teach Proteomics Concepts with Problem-Based Techniques

    Science.gov (United States)

    Short, Michael; Short, Anne; Vankempen, Rachel; Seymour, Michael; Burnatowska-Hledin, Maria

    2010-01-01

    Practical instruction of proteomics concepts was provided using high-performance liquid chromatography coupled with a mass selective detection system (HPLC-MS) for the analysis of simulated protein digests. The samples were prepared from selected dipeptides in order to facilitate the mass spectral identification. As part of the prelaboratory…

  1. HPLC for quality control of polyimides

    Science.gov (United States)

    Young, P. R.; Sykes, G. F.

    1979-01-01

    High Pressure Liquid Chromatography (HPLC) as a quality control tool for polyimide resins and prepregs are presented. A data base to help establish accept/reject criteria for these materials was developed. This work is intended to supplement, not replace, standard quality control tests normally conducted on incoming resins and prepregs. To help achieve these objectives, the HPLC separation of LARC-160 polyimide precursor resin was characterized. Room temperature resin aging effects were studied. Graphite reinforced composites made from fresh and aged resin were fabricated and tested to determine if changes observed by HPLC were significant.

  2. Expermental Studies of quantitative evaluation using HPLC

    Directory of Open Access Journals (Sweden)

    Ki Rok Kwon

    2005-06-01

    Full Text Available Methods : This study was conducted to carry out quantitative evaluation using HPLC Content analysis was done using HPLC Results : According to HPLC analysis, each BVA-1 contained approximately 0.36㎍ melittin, and BVA-2 contained approximately 0.54㎍ melittin. But the volume of coating was so minute, slight difference exists between each needle. Conclusion : Above results indicate that the bee venom acupuncture can complement shortcomings of syringe usage as a part of Oriental medicine treatment, but extensive researches should be done for further verification.

  3. HPLC for quality control of polyimides

    Science.gov (United States)

    Young, P. R.; Sykes, G. F.

    1979-01-01

    High Pressure Liquid Chromatography (HPLC) as a quality control tool for polyimide resins and prepregs are presented. A data base to help establish accept/reject criteria for these materials was developed. This work is intended to supplement, not replace, standard quality control tests normally conducted on incoming resins and prepregs. To help achieve these objectives, the HPLC separation of LARC-160 polyimide precursor resin was characterized. Room temperature resin aging effects were studied. Graphite reinforced composites made from fresh and aged resin were fabricated and tested to determine if changes observed by HPLC were significant.

  4. Preparing for Exascale: Towards convection-permitting, global atmospheric simulations with the Model for Prediction Across Scales (MPAS)

    Science.gov (United States)

    Heinzeller, Dominikus; Duda, Michael G.; Kunstmann, Harald

    2017-04-01

    With strong financial and political support from national and international initiatives, exascale computing is projected for the end of this decade. Energy requirements and physical limitations imply the use of accelerators and the scaling out to orders of magnitudes larger numbers of cores then today to achieve this milestone. In order to fully exploit the capabilities of these Exascale computing systems, existing applications need to undergo significant development. The Model for Prediction Across Scales (MPAS) is a novel set of Earth system simulation components and consists of an atmospheric core, an ocean core, a land-ice core and a sea-ice core. Its distinct features are the use of unstructured Voronoi meshes and C-grid discretisation to address shortcomings of global models on regular grids and the use of limited area models nested in a forcing data set, with respect to parallel scalability, numerical accuracy and physical consistency. Here, we present work towards the application of the atmospheric core (MPAS-A) on current and future high performance computing systems for problems at extreme scale. In particular, we address the issue of massively parallel I/O by extending the model to support the highly scalable SIONlib library. Using global uniform meshes with a convection-permitting resolution of 2-3km, we demonstrate the ability of MPAS-A to scale out to half a million cores while maintaining a high parallel efficiency. We also demonstrate the potential benefit of a hybrid parallelisation of the code (MPI/OpenMP) on the latest generation of Intel's Many Integrated Core Architecture, the Intel Xeon Phi Knights Landing.

  5. Electrocatalytic Mechanism Involving Michaelis-Menten Kinetics at the Preparative Scale: Theory and Applicability to Photocurrents from a Photosynthetic Algae Suspension With Quinones.

    Science.gov (United States)

    Longatte, Guillaume; Guille-Collignon, Manon; Lemaître, Frédéric

    2017-06-15

    In the past years, many strategies have been implemented to benefit from oxygenic photosynthesis to harvest photosynthetic electrons and produce a significant photocurrent. Therefore, electrochemical tools were considered and have globally relied on the electron transfer(s) between the photosynthetic chain and a collecting electrode. In this context, we recently reported the implementation of an electrochemical set-up at the preparative scale to produce photocurrents from a Chlamydomonas reinhardtii algae suspension with an appropriate mediator (2,6-DCBQ) and a carbon gauze as the working electrode. In the present work, we wish to describe a mathematical modeling of the recorded photocurrents to better understand the effects of the experimental conditions on the photosynthetic extraction of electrons. In that way, we established a general model of an electrocatalytic mechanism at the preparative scale (that is, assuming a homogenous bulk solution at any time and a constant diffusion layer, both assumptions being valid under forced convection) in which the chemical step involves a Michaelis-Menten-like behaviour. Dependences of transient and steady-state corresponding currents were analysed as a function of different parameters by means of zone diagrams. This model was tested to our experimental data related to photosynthesis. The corresponding results suggest that competitive pathways beyond photosynthetic harvesting alone should be taken into account. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. The preparation and characterization of chitin and chitosan under large-scale submerged fermentation level using shrimp by-products as substrate.

    Science.gov (United States)

    Zhang, Hongcai; Yun, Sanyue; Song, Lingling; Zhang, Yiwen; Zhao, Yanyun

    2017-03-01

    The crustacean shells of crabs and shrimps produces quantities of by-products, leading to seriously environmental pollution and human health problems during industrial processing, yet they turned into high-value useful products, such as chitin and chitosan. To prepare them under large-scale submerged fermentation level, shrimp shell powders (SSPs) was fermented by successive three-step fermentation of Serratia marcescens B742, Lactobacillus plantarum ATCC 8014 and Rhizopus japonicus M193 to extract chitin and chitosan based on previously optimal conditions. Moreover, the key parameters was investigated to monitor the changes of resulted products during fermentation process. The results showed that the yield of prepared chitin and chitosan reached 21.35 and 13.11% with the recovery rate of 74.67 and 63.42%, respectively. The degree of deacetylation (DDA) and molecular mass (MM) of produced chitosan were 81.23% and 512.06kDa, respectively. The obtained chitin and chitosan was characterized using Fourier transform infrared spectrometer (FT-IR) and X-ray diffraction (XRD) analysis. The established microbial fermentation method can be applied for the industrial large-scale production of chitin and chitosan, while the use of chemical reagents was significantly reduced. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Preparation of Nano-Scale Biopolymer Extracted from Coconut Residue and Its Performance as Drag Reducing Agent (DRA

    Directory of Open Access Journals (Sweden)

    Hasan Muhammad Luqman Bin

    2017-01-01

    Full Text Available Drag or frictional force is defined as force that acts opposite to the object’s relative motion through a fluid which then will cause frictional pressure loss in the pipeline. Drag Reducing Agent (DRA is used to solve this issue and most of the DRAs are synthetic polymers but has some environmental issues. Therefore for this study, biopolymer known as Coconut Residue (CR is selected as the candidate to replace synthetic polymers DRA. The objective of this study is to evaluate the effectiveness of Nano-scale biopolymer DRA on the application of water injection system. Carboxymethyl cellulose (CMC is extracted by synthesizing the cellulose extracted from CR under the alkali-catalyzed reaction using monochloroacetic acid. The synthesize process is held in controlled condition whereby the concentration of NaOH is kept at 60%wt, 60 °C temperature and the reaction time is 4 hours. For every 25 g of dried CR used, the mass of synthesized CMC yield is at an average of 23.8 g. The synthesized CMC is then grinded in controlled parameters using the ball milling machine to get the Nano-scale size. The particle size obtained from this is 43.32 Nm which is in range of Nano size. This study proved that Nano-size CMC has higher percentage of drag reduction (%DR and flow increase (%FI if compared to normal-size CMC when tested in high and low flow rate; 44% to 48% increase in %DR and %FI when tested in low flow rate, and 16% to 18% increase in %DR and %FI when tested in high flow rate. The success of this research shows that Nano-scale DRA can be considered to be used to have better performance in reducing drag.

  8. Applying quality by design principles to the small-scale preparation of the bone-targeting therapeutic radiopharmaceutical rhenium-188-HEDP.

    Science.gov (United States)

    Lange, Rogier; Ter Heine, Rob; van der Gronde, Toon; Selles, Suzanne; de Klerk, John; Bloemendal, Haiko; Hendrikse, Harry

    2016-07-30

    Rhenium-188-HEDP ((188)Re-HEDP) is a therapeutic radiopharmaceutical for treatment of osteoblastic bone metastases. No standard procedure for the preparation of this radiopharmaceutical is available. Preparation conditions may influence the quality and in vivo behaviour of this product. In this study we investigate the effect of critical process parameters on product quality and stability of (188)Re-HEDP. A stepwise approach was used, based on the quality by design (QbD) concept of the ICH Q8 (Pharmaceutical Development) guideline. Potential critical process conditions were identified. Variables tested were the elution volume, the freshness of the eluate, the reaction temperature and time, and the stability of the product upon dilution and storage. The impact of each variable on radiochemical purity was investigated. The acceptable ranges were established by boundary testing. With 2ml eluate, adequate radiochemical purity and stability were found. Nine ml eluate yielded a product that was less stable. Using eluate stored for 24h resulted in acceptable radiochemical purity. Complexation for 30min at room temperature, at 60°C and at 100°C generated appropriate and stable products. A complexation time of 10min at 90°C was too short, whereas heating 60min resulted in products that passed quality control and were stable. Diluting the end product and storage at 32.5°C resulted in notable decomposition. Two boundary tests, an elution volume of 9ml and a heating time of 10min, yielded products of inadequate quality or stability. The product was found to be instable after dilution or when stored above room temperature. Our findings show that our previously developed preparation method falls well within the proven acceptable ranges. Applying QbD principles is feasible and worthwhile for the small-scale preparation of radiopharmaceuticals. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Facile preparation of monodisperse, impurity-free, and antioxidation copper nanoparticles on a large scale for application in conductive ink.

    Science.gov (United States)

    Zhang, Yu; Zhu, Pengli; Li, Gang; Zhao, Tao; Fu, Xianzhu; Sun, Rong; Zhou, Feng; Wong, Ching-ping

    2014-01-08

    Monodisperse copper nanoparticles with high purity and antioxidation properties are synthesized quickly (only 5 min) on a large scale (multigram amounts) by a modified polyol process using slightly soluble Cu(OH)2 as the precursor, L-ascorbic acid as the reductant, and PEG-2000 as the protectant. The resulting copper nanoparticles have a size distribution of 135 ± 30 nm and do not suffer significant oxidation even after being stored for 30 days under ambient conditions. The copper nanoparticles can be well-dispersed in an oil-based ink, which can be silk-screen printed onto flexible substrates and then converted into conductive patterns after heat treatment. An optimal electrical resistivity of 15.8 μΩ cm is achieved, which is only 10 times larger than that of bulk copper. The synthesized copper nanoparticles could be considered as a cheap and effective material for printed electronics.

  10. Preparative separation of glycoalkaloids α-solanine and α-chaconine by centrifugal partition chromatography.

    Science.gov (United States)

    Attoumbré, Jacques; Lesur, David; Giordanengo, Philippe; Baltora-Rosset, Sylvie

    2012-11-01

    The main glycoalkaloids of a commercial potato cultivar, α-chaconine and α-solanine, were extracted from sprouts of Solanum tuberosum cv. Pompadour by a mixture of MeOH/H(2)O/CH(3)COOH (400/100/50, v/v/v). In these conditions, 2.8±0.62g of crude extract were obtained from 50g of fresh sprouts and the total glycoalkaloid content was determined by analytical HPLC at 216.5mg/100g. α-Chaconine and α-solanine were separated in a preparative scale using centrifugal partition chromatography (CPC). In a solvent system composed of a mixture of ethyl acetate/butanol/water (15/35/50, v/v/v), α-chaconine (54mg) and α-solanine (15mg) were successfully isolated from the crude extract in one step of purification. The purity of isolated compounds was determined to be higher than 92% by HPLC analysis.

  11. Determination of diarylheptanoids from Alpinia officinarum (Lesser Galangal) by HPLC with photodiode array and electrochemical detection.

    Science.gov (United States)

    Liu, Zhihua; Sang, Shengmin; Hartman, Thomas G; Ho, Chi-Tang; Rosen, Robert T

    2005-01-01

    Normal-phase column chromatography followed by semi-preparative reversed-phase HPLC has been used to isolate, from the rhizomes of Alpinia officinarum, five diarylheptanoids identified as 5-hydroxy-7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-3-heptanone, 5-methoxy-7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-3-heptanone, 7-(4"-hydroxyphenyl)-1-phenylhept-4-en-3-one, 7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-hept-4-en-3-one, 1,7-diphenylhept-4-en-3-one. The levels of these five diarylheptanoids in root material were determined quantitatively by HPLC with UV detection and the assay methods so developed were simple, rapid and accurate. Four of the diarylheptanoids could also be detected by HPLC with electrochemical detection (ECD) in the oxidative mode, and ECD was found to have a higher sensitivity than photodiode array detection.

  12. Studies on the Renaturation with Simultaneous Purification of Recombinant Human Proinsulin with Unit of Simultaneous Renaturation and Purification of Protein in Semi-preparative Scale

    Institute of Scientific and Technical Information of China (English)

    Quan BAI; Yu KONG; Xin Du GENG

    2003-01-01

    The renaturation and purification of recombinant human proinsulin (rh-proinsulin) expressed in E. Coli with the unit of simultaneous renaturation and purification of protein (USRPP) in semi-preparative scale was studied. The result shows that rh-proinsulin extracted with 8.0 mol/L urea can be renatured and purified simultaneously in 45 minutes with the USRPP (10×50 mm ID). The purity of rh-proinsulin was found to be more than 90% and the mass recovery to be more than 80%. The renaturation effect of rh-proinsulin with the USRPP was tested by enzyme cleavage for obtaining insulin. In addition, the result was further confirmed with RPLC, SDS-PAGE electrophoresis, and MALDI-TOF, respectively.

  13. A Simple Design to Realize Micro-column Separation by Conventional Analytical HPLC

    Institute of Scientific and Technical Information of China (English)

    GONG,Wenjun; ZHANG,Junxia; ZHANG,Yuping; ZHANG,Yijun; TIAN,Mengkui; WU,Dafu

    2009-01-01

    The conventional analytical HPLC was successfully developed for micro-column separation by using a simple eluate splitting system,self-preparation of packing column and on-capillary column detector in our laboratory.Porous inlet frit in fused silica capillary was rapidly prepared by sintering stainless steel powders under 500 meshes for about 20 s.The use of such frits or metal meshes in capillary to retain C18 particles of chromatographic packing was demonstrated to be stable and specially robust with continuous packing and long chromatographic runs.Furthermore,the chromatographic behavior was detailedly evaluated by changing the flow rate and the percentage of mobile phase using the prepared capillary column.Under the optimal experimental conditions,baseline separation of the model analytes including thiourea,benzene,toluene,ethylbenzene was obtained with a high column efficiency near 70000N (plates/m) by the developed capillary-HPLC.

  14. Preparation and fabrication of a full-scale, sagittal-sliced, 3D-printed, patient-specific radiotherapy phantom.

    Science.gov (United States)

    Craft, Daniel F; Howell, Rebecca M

    2017-09-01

    Patient-specific 3D-printed phantoms have many potential applications, both research and clinical. However, they have been limited in size and complexity because of the small size of most commercially available 3D printers as well as material warping concerns. We aimed to overcome these limitations by developing and testing an effective 3D printing workflow to fabricate a large patient-specific radiotherapy phantom with minimal warping errors. In doing so, we produced a full-scale phantom of a real postmastectomy patient. We converted a patient's clinical CT DICOM data into a 3D model and then sliced the model into eleven 2.5-cm-thick sagittal slices. The slices were printed with a readily available thermoplastic material representing all body tissues at 100% infill, but with air cavities left open. Each slice was printed on an inexpensive and commercially available 3D printer. Once the printing was completed, the slices were placed together for imaging and verification. The original patient CT scan and the assembled phantom CT scan were registered together to assess overall accuracy. The materials for the completed phantom cost $524. The printed phantom agreed well with both its design and the actual patient. Individual slices differed from their designs by approximately 2%. Registered CT images of the assembled phantom and original patient showed excellent agreement. Three-dimensional printing the patient-specific phantom in sagittal slices allowed a large phantom to be fabricated with high accuracy. Our results demonstrate that our 3D printing workflow can be used to make large, accurate, patient-specific phantoms at 100% infill with minimal material warping error. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  15. Preparative scale purification of fucosyl-N-acetylglucosamine disaccharides and their evaluation as potential prebiotics and antiadhesins.

    Science.gov (United States)

    Becerra, Jimmy E; Coll-Marqués, José M; Rodríguez-Díaz, Jesús; Monedero, Vicente; Yebra, María J

    2015-09-01

    Fucosyl-N-acetylglucosamine disaccharides are important core structures that form part of human mucosal and milk glyco-complexes. We have previously shown that AlfB and AlfC α-L-fucosidases from Lactobacillus casei are able to synthesize fucosyl-α-1,3--N-acetylglucosamine (Fuc-α1,3-GlcNAc) and fucosyl-α-1,6-N-acetylglucosamine (Fuc-α1,6-GlcNAc), respectively, in transglycosylation reactions. Here, these reactions were performed in a semipreparative scale, and the produced disaccharides were purified. The maximum yields obtained of Fuc-α1,3-GlcNAc and Fuc-α1,6-GlcNAc were 4.2 and 9.3 g/l, respectively. The purified fucosyl-disaccharides were then analyzed for their prebiotic effect in vitro using strains from the Lactobacillus casei/paracasei/rhamnosus group and from Bifidobacterium species. The results revealed that 6 out of 11 L. casei strains and 2 out of 6 L. rhamnosus strains tested were able to ferment Fuc-α1,3-GlcNAc, and L. casei BL87 and L. rhamnosus BL327 strains were also able to ferment Fuc-α1,6-GlcNAc. DNA hybridization experiments suggested that the metabolism of Fuc-α1,3-GlcNAc in those strains relies in an α-L-fucosidase homologous to AlfB. Bifidobacterium breve and Bibidobacterium pseudocatenolatum species also metabolized Fuc-α1,3-GlcNAc. Notably, L-fucose was excreted from all the Lactobacillus and Bifidobacterium strains fermenting fucosyl-disaccharides, except from strains L. rhamnosus BL358 and BL377, indicating that in these latest strains, L-fucose was catabolized. The fucosyl-disaccharides were also tested for their inhibitory potential of pathogen adhesion to human colon adenocarcinoma epithelial (HT29) cell line. Enteropathogenic Escherichia coli (EPEC) strains isolated from infantile gastroenteritis were used, and the results showed that both fucosyl-disaccharides inhibited adhesion to different extents of certain EPEC strains to HT29 cells in tissue culture.

  16. Preparation of a recombinant adeno-associated viral vector with a mutation of human factor IX in large scale and its expression in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A series of adeno-associated viral vectors conraining a mutation of human factor IX (hFIXR338A) with different regulation elements were constructed and used to transduce cell lines. The plasmids and the stable transduction cell clones with high expression level of hFIXR338Awere obtained by selecting and optimizing, and then, the recombinant adeno-associated viral vector with hFIXR338Awas prepared via novel rHSV/AAV hybrid virus packaging system on a large scale, which contained the capsid protein genes. A method for producing rAAV-hFIXR338A viral stocks on a large scale and higher fiter was established,which can be used for industrial purpose. The titer of rAAV-hFIXR338A was more than 1.25x1012 particle/mL, and then, a mammalian cell line, C2C12 and the factor IXknock-out mice were transfected with the rAAV-hFIXR338Ain vitro and in vivo. The results show that the high-level expression of rAAV-hFIXR338A was achieved in cell line and hemophilia B mice. It reached at (2551.32±92.14) ng@ (106cells)-1 @ (24 h)-1 in C2C12 cell in vitro and had a peak concentration of 463.28 ng/mL in mice treated with rAAV-hFIX R338A, which was as high as the expression of rAAV-hFIX -wt (2565.76±64.36) ng@ (106 cells)-1@ (24 h)-1 in C2C12 and 453.92 ng/mL in the mice treated with rAAV-hFIX-wt) in vitro and in vivo, there is no any difference between two groups, but the clotting activity of hFIXR338A is about 2.46times higher than that of hFIX-wt. It was first reported that a mutation of human factor IX was used into gene therapy research for hemophilia B, meanwhile, a novel packaging system, rAAV/HSV was used for preparation of rAAV-hFIX R338A on a large scale, which laid the foundation of industrial production for applying rAAV viral stocks to gene therapy clinical trial for hemophilia B mediated with rAAV-hFIX.``

  17. Preparative separation of polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin coupled with preparative high performance liquid chromatography.

    Science.gov (United States)

    Li, Aifeng; Xuan, Hongzhuan; Sun, Ailing; Liu, Renmin; Cui, Jichun

    2016-02-15

    In this study, a preparative separation method was developed for isolation of eleven polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin (MAR) coupled with preparative high performance liquid chromatography (PHPLC). Water-soluble fraction of Chinese propolis was first "prefractioned" using MAR, which yielded four subfractions. The four subfractions were then isolated by PHPLC with an isocratic elution of methanol-water. Finally, eleven polyphenols were purified from Chinese propolis including caffeic acid, ferulic acid, isoferulic acid, 3,4-dimethoxy cinnamic acid, pinobanksin, caffeic acid benzyl ester, caffeic acid phenethyl ester, apigenin, pinocembrin, chrysin and galangin. The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. The method developed was simple, effective, rapid, scalable and economical, and it was a promising basis for large-scale preparation of multiple components from natural products.

  18. Comprehensive quality evaluation of Chishao by HPLC

    OpenAIRE

    Jian Zaiyou; Wang Wenquan; Xu Guifang; Meng Li; Hou Junling

    2013-01-01

    Objective: The purpose of this paper is to comprehensively evaluate the quality of Chishao. Methods: In the experiment of this paper, the fingerprint spectrums of Chishao in all locations are established by RP-HPLC and the model of principle component analysis with the RP-HPLC peak areas is established. Results: The quality of Chishao in the northern part of China or that made of Paeonia lactiflora is better than that of these in others or that made of other species. The quality of Chishao co...

  19. Evaluation of regional-scale water level simulations using various river routing schemes within a hydrometeorological modelling framework for the preparation of the SWOT mission

    Science.gov (United States)

    Häfliger, V.; Martin, E.; Boone, A. A.; Habets, F.; David, C. H.; Garambois, P. A.; Roux, H.; Ricci, S. M.; Thévenin, A.; Berthon, L.; Biancamaria, S.

    2014-12-01

    The ability of a regional hydrometeorological model to simulate water depth is assessed in order to prepare for the SWOT (Surface Water and Ocean Topography) mission that will observe free surface water elevations for rivers having a width larger than 50/100 m. The Garonne river (56 000 km2, in south-western France) has been selected owing to the availability of operational gauges, and the fact that different modeling platforms, the hydrometeorological model SAFRAN-ISBA-MODCOU and several fine scale hydraulic models, have been extensively evaluated over two reaches of the river. Several routing schemes, ranging from the simple Muskingum method to time-variable parameter kinematic and diffusive waves schemes with time varying parameters, are tested using predetermined hydraulic parameters. The results show that the variable flow velocity scheme is advantageous for discharge computations when compared to the original Muskingum routing method. Additionally, comparisons between water level computations and in situ observations led to root mean square errors of 50-60 cm for the improved Muskingum method and 40-50 cm for the kinematic-diffusive wave method, in the downstream Garonne river. The error is larger than the anticipated SWOT resolution, showing the potential of the mission to improve knowledge of the continental water cycle. Discharge computations are also shown to be comparable to those obtained with high-resolution hydraulic models over two reaches. However, due to the high variability of river parameters (e.g. slope and river width), a robust averaging method is needed to compare the hydraulic model outputs and the regional model. Sensitivity tests are finally performed in order to have a better understanding of the mechanisms which control the key hydrological processes. The results give valuable information about the linearity, Gaussianity and symetry of the model, in order to prepare the assimilation of river heights in the model.

  20. An Inexpensive Digital Gradient Controller for HPLC.

    Science.gov (United States)

    Brady, James E.; Carr, Peter W.

    1983-01-01

    Use of gradient elution techniques in high performance liquid chromatography (HPLC) is often essential for direct separation of complex mixtures. Since most commercial controllers have features that are of marginal value for instructional purposes, a low-cost controller capable of illustrating essential features of gradient elution was developed.…

  1. Methods and applications of HPLC-AMS

    Science.gov (United States)

    Buchholz, Bruce A.; Dueker, Stephen R.; Lin, Yumei; Clifford, Andrew J.; Vogel, John S.

    2000-10-01

    Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a 14C-labeled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the 14C content above the control predose tissue and converting to equivalents of the parent compound. High performance liquid chromatography (HPLC) is an excellent method for the chemical separation of complex mixtures whose profiles afford estimation of biochemical pathways of metabolism. Compounds elute from the HPLC systems with characteristic retention times and can be collected in fractions that can then be graphitized for AMS measurement. Unknowns are tentatively identified by co-elution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the 14C signal. Thoroughly accounting for the carbon inventory in the LC solvents, ion-pairing agents, samples, and carriers adds some complexity to the analysis. In most cases the total carbon inventory is dominated by carrier. Baseline background and stability need to be carefully monitored. Limits of quantitation near 10 amol of 14C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected 14C activity <0.17 Bq (4.5 pCi) on the HPLC column.

  2. An Inexpensive Digital Gradient Controller for HPLC.

    Science.gov (United States)

    Brady, James E.; Carr, Peter W.

    1983-01-01

    Use of gradient elution techniques in high performance liquid chromatography (HPLC) is often essential for direct separation of complex mixtures. Since most commercial controllers have features that are of marginal value for instructional purposes, a low-cost controller capable of illustrating essential features of gradient elution was developed.…

  3. PS-b-PEO/Silica Films with Regular and Reverse Mesostructures of Large Characteristic Length Scales Prepared by Solvent Evaporation-Induced Self-Assembly

    Energy Technology Data Exchange (ETDEWEB)

    YU,KUI; BRINKER,C. JEFFREY; HURD,ALAN J.; EISENBERG,ADI

    2000-11-22

    Since the discovery of surfactant-templated silica by Mobil scientists in 1992, mesostructured silica has been synthesized in various forms including thin films, powders, particles, and fibers. In general, mesostructured silica has potential applications, such as in separation, catalysis, sensors, and fluidic microsystems. In respect to these potential applications, mesostructured silica in the form of thin films is perhaps one of the most promising candidates. The preparation of mesostructured silica films through preferential solvent evaporation-induced self-assembly (EISA) has recently received much attention in the laboratories. However, no amphiphile/silica films with reverse mesophases have ever been made through this EISA procedure. Furthermore, templates employed to date have been either surfactants or poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) triblock copolymers, such as pluronic P-123, both of which are water-soluble and alcohol-soluble. Due to their relatively low molecular weight, the templated silica films with mesoscopic order have been limited to relatively small characteristic length scales. In the present communication, the authors report a novel synthetic method to prepare mesostructured amphiphilic/silica films with regular and reverse mesophases of large characteristic length scales. This method involves evaporation-induced self-assembly (EISA) of amphiphilic polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymers. In the present study, the PS-b-PEO diblocks are denoted as, for example, PS(215)-b-PEO(100), showing that this particular sample contains 215 S repeat units and 100 EO repeat units. This PS(215)-b-PEO(100) diblock possesses high molecular weight and does not directly mix with water or alcohol. To the authors knowledge, no studies have reported the use of water-insoluble and alcohol-insoluble amphiphilic diblocks as structure-directing agents in the synthesis of mesostructured silica films through

  4. An improved HPLC method for determination of colocynthin in colocynth

    Directory of Open Access Journals (Sweden)

    M. Shekarchi

    2015-10-01

    Full Text Available Background and objectives: Colocynthin is the major active secondary metabolite of colocynth, Citrullus colocynthis (L. Schrad, which has been used in traditional and ethno medicine of many countries.  It could be considered as an active marker for quality control of colocynth and its herbal products. Analysis and standardization of colocynth and its herbal preparations are a critical issue for their safe applications in phytotherapy and traditional medicine. In the present work, a simple and efficient sample preparation was developed and optimized through combination of matrix solid phase dispersion and ultrasonic assisted extraction. In addition, analytical reversed-phase HPLC method was optimized for analyzing the concentration of colocynthin in colocynth pulp. Methods: Powdered colocynth pulp was grinded with diatomaceous earth to obtain a homogenous mixture. The blend was mixed with methanol and extracted by sonication, followed by centrifugation and filtration. The analytical chromatographic separation was carried out using Luna C18 in isocratic elution with methanol: isopropanol: water: triflouroacetic acid (30:10:60:0.1 v/v. The method was validated as well.  Results: The validation parameters were determines as follows, linear range (r2 = 0.999, 75-500 μg/mL, precision (intra-day < 2.7%, inter-day = 4.4% and accuracy measured via determination of recovery (90-107%. The limit of detection and quantization were calculated 8.5 and 25.7 μg/mL, respectively. Conclusion: Regarding the relatively high content of colocynthin in colocynth pulp, the validated HPLC method could be applied for quality control of colocynth pulp used in Traditional Persian Medicine.

  5. HPLC method for the quantification of procyanidins in cocoa and chocolate samples and correlation to total antioxidant capacity.

    Science.gov (United States)

    Adamson, G E; Lazarus, S A; Mitchell, A E; Prior, R L; Cao, G; Jacobs, P H; Kremers, B G; Hammerstone, J F; Rucker, R B; Ritter, K A; Schmitz, H H

    1999-10-01

    Monomeric and oligomeric procyanidins present in cocoa liquors and chocolates were separated and quantified in four different laboratories using a normal-phase high-performance liquid chromatography (HPLC) method with fluorescence detection. Procyanidin standards through decamers were obtained by extraction from cocoa beans, enrichment by Sephadex LH-20 gel permeation chromatography, and final purification by preparative normal-phase HPLC. The purity of each oligomeric fraction was assessed using HPLC coupled to mass spectrometry. A composite standard was then prepared, and calibration curves were generated for each oligomeric class using a quadratic fit of area sum versus concentration. Results obtained by each of the laboratories were in close agreement, which suggests this method is reliable and reproducible for quantification of procyanidins. Furthermore, the procyanidin content of the samples was correlated to the antioxidant capacity measured using the ORAC assay as an indicator for potential biological activity.

  6. Semisynthetic preparation and isolation of dimeric procyanidins B1-B8 from roasted hazelnut skins (Corylus avellana L.) on a large scale using countercurrent chromatography.

    Science.gov (United States)

    Esatbeyoglu, Tuba; Juadjur, Andreas; Wray, Victor; Winterhalter, Peter

    2014-07-23

    Dimeric procyanidins B1-B8 were produced via semisynthesis from a polymeric proanthocyanidin fraction of hazelnut skins (Corylus avellana L.). This polymeric fraction was found to consist mostly of (+)-catechin and (-)-epicatechin as upper units. Therefore, according to the choice of nucleophile agent, it is possible to semisynthesize dimeric procyanidins B1, B3, B6, and B7 with (+)-catechin and B2, B4, B5, and B8 with (-)-epicatechin. The semisynthetic mixtures were separated on a preparative scale using high-speed countercurrent chromatography (HSCCC) and low-speed rotary countercurrent chromatography (LSRCCC). C4 → C8 linked dimeric procyanidins B1-B4 were isolated in amounts of 350-740 mg. To the best of the authors' knowledge this is the first study isolating dimeric procyanidins B1-B8 in large amounts with countercurrent chromatography. Moreover, the dimeric prodelphinidins B1, B2, and B3 and their structural elucidation by (1)H NMR spectroscopy without derivatization are described for hazelnuts as natural compounds for the first time.

  7. Metastable tetragonal Cu2Se hyperbranched structures: large-scale preparation and tunable electrical and optical response regulated by phase conversion.

    Science.gov (United States)

    Zhu, Jinbao; Li, Qiuyang; Bai, Liangfei; Sun, Yongfu; Zhou, Min; Xie, Yi

    2012-10-08

    Despite the promising applications of copper selenide nanoparticles, an in-depth elucidation of the inherent properties of tetragonal Cu(2)Se (β-Cu(2)Se) has not been performed because of the lack of a facile synthesis on the nanoscale and an energy-intensive strategy is usually employed. In this work, a facile wet-chemical strategy, employing HCOOH as reducing agent, has been developed to access single-crystalline metastable β-Cu(2)Se hyperbranched architectures for the first time. The process avoids hazardous chemistry and high temperatures, and thus opens up a facile approach to the large-scale low-cost preparation of metastable β-Cu(2)Se hyperbranched architectures. A possible growth mechanism to explain the formation of the β-Cu(2)Se dendritic morphology has been proposed based on time-dependent shape evolution. Further investigations revealed that the metastable β-Cu(2)Se can convert into the thermodynamically more stable cubic α-Cu(2-x)Se maintaining the dendritic morphology. An increase in electrical conductivity and a tunable optical response were observed under ambient conditions. This behavior can be explained by the oxidation of the surface of the β-Cu(2)Se hyperbranched structures, ultimately leading to solid-state phase conversion from β-Cu(2)Se into superionic conductor α-Cu(1.8)Se, which has potential applications in energy-related devices and sensors.

  8. High Purity and Large-scale Preparation of β-Ga2O3 Nanowires and Nanosheets by CVD and Their Raman and Photoluminescence Characteristics

    Institute of Scientific and Technical Information of China (English)

    YU Zhou; GONG Min; SUN Xiao-song; YANG Zhi-mei; CHEN Hao; WU Zhan-wen; JIN Yong; JIAO Zhi-feng; HE Yi; WANG Hui; LIU Jun-gang

    2007-01-01

    Ga2O3 nano-structures,nanowires and nanosheets are produced on Au pre-coated(111) silicon substrates with chemical vapor deposition(CVD) technique.By evaporating pure Ga powder in the H2O atmosphere under ambient pressure the large-scale preparation of β-Ga2O3 with monoclinic crystalline structure is achieved.The crystalline structures and morphologies of produced Ga2O3 nano-structures are characterized by means of scanning electron microscope(SEM),X-ray diffraction(XRD),selected area electron diffraction(SAED) and transmission electron microscope(TEM).Raman spectrum reveals the typical vibration modes of Ga2O3.The vibration mode shifts corresponding to Ga2O3 nano-structures are not found.Two distinguish photoluminescence(PL) emissions are found at about 399 nm and 469 nm owing to the VO-VGa excitation and VO-VGa-O excitation,respectively.The growth mechanisms of Ga2O3 nanowires and nanosheets are discussed with vapor-liquid-solid(VLS) and vapor-solid(VS) mechanisms.

  9. Preparation of guar gum scaffold film grafted with ethylenediamine and fish scale collagen, cross-linked with ceftazidime for wound healing application.

    Science.gov (United States)

    Jana, Piyali; Mitra, Tapas; Selvaraj, Thirupathi Kumara Raja; Gnanamani, A; Kundu, P P

    2016-11-20

    Present study describes the synthesis of carboxymethyl guar gum (CMGG) from the native guar gum (GG) and the prepared CMGG is grafted with ethylenediamine (EDA) to form aminated CMGG. Then, fish scale collagen and aminated CMGG are cross-linked by ceftazidime drug through non- covalent ionic interaction. The resultant cross-linked film is subjected to the analysis of (1)HNMR, ATR-FTIR, TGA, SEM and XRD. The TNBS results revealed that 45% of interaction between EDA and CMGG and 90-95% of Ceftazidime is released from aminated CMGG-Ceftazidime-Collagen (ACCC) film after 96h of incubation at physiological pH. In vitro cell line studies reveal the biocompatibility of the cross-linked film and the antimicrobial studies display the growth inhibition against Staphylococcus aureus and Pseudomonas aeruginosa organisms. Overall, the study indicates that the incorporation of Ceftazidime into collagen and aminated CMGG can improve the functional property of aminated CMGG as well as collagen, leading to its biomedical applications.

  10. Characteristics of structured lipid prepared by lipase-catalyzed acidolysis of roasted sesame oil and caprylic acid in a bench-scale continuous packed bed reactor.

    Science.gov (United States)

    Kim, Byung Hee; Akoh, Casimir C

    2006-07-12

    Structured lipid (SL) was prepared from roasted sesame oil and caprylic acid (CA) by Rhizomucor miehei lipase-catalyzed acidolysis in a bench-scale continuous packed bed reactor. Total incorporation and acyl migration of CA in the SL were 42.5 and 3.1 mol %, respectively, and the half-life of the lipase was 19.2 days. The SL displayed different physical and chemical properties, less saturated dark brown color, lower viscosity, lower melting and crystallization temperature ranges, higher melting and crystallization enthalpies, higher smoke point, higher saponification value, and lower iodine value, in comparison to those of unmodified sesame oil. The oxidative stability of purified SL was lower than that of sesame oil. There were no differences in the contents of unsaponifiables including tocopherols and phytosterols. However, total sesame lignans content was decreased in SL due to the loss of sesamol when compared to sesame oil. Most of the 70 volatiles present in roasted sesame oil were removed from SL during short-path distillation of SL. These results indicate that the characteristics of SL are different from those of original sesame oil in several aspects except for the contents of tocopherols and phytosterols.

  11. 聚天冬氨酸阻垢剂的制备及性能评价%Preparation and Performance Evaluation of Poly-aspartic Acid Scale Inhibitor

    Institute of Scientific and Technical Information of China (English)

    杨红丽; 姬彩云

    2015-01-01

    Poly-aspartic acid has good scale inhibition effect. Using maleic anhydride and ammonium chloride, poly-aspartic acid was prepared by hot-polymerization. And the optimum reaction conditions were obtained by or-thogonal experiment as follows:molar ratio of maleic anhydride/ammonium chloride was 1∶1. 2,reaction teampra-ture was 140℃,and reaction time was 5h.%聚天冬氨酸具有较好的阻垢效果。采用热引发聚合,以马来酸酐、氯化铵为原料,制备了绿色阻垢剂聚天冬氨酸,通过正交实验确定了最佳合成条件,并对其进行了性能评价。最佳合成条件为:马来酸酐和氯化铵的摩尔比为1∶1.2,反应温度为140℃,反应时间为5 h。

  12. A microdevice assisted approach for the preparation, characterization and selection of continuous aqueous two-phase systems: from micro to bench-scale.

    Science.gov (United States)

    Vázquez-Villegas, Patricia; Ouellet, Eric; González, Claudia; Ruiz-Ruiz, Federico; Rito-Palomares, Marco; Haynes, Charles A; Aguilar, Oscar

    2016-07-05

    Aqueous two-phase systems (ATPS) have emerged as an alternative strategy for the recovery and purification of a wide variety of biological products. Typical process development requires a large screening of experimental conditions towards industrial adoption where continuous processes are preferred. In this work, it was proved that under certain flow conditions, ATPS could be formed continuously inside a microchannel, starting from stocks of phase components. Staggered herringbone chaotic micromixers included within the device sequentially and rapidly prepare two-phase systems across an entire range of useful phase compositions. Two-phase diagrams (binodal curves) were easily plotted using the cloud-point method for systems of different components and compared with previously reported curves for each system, proving that phase formation inside the device correlated with the previously reported diagrams. A proof of concept for sample partitioning in such a microdevice was performed with two different experimental models: BSA and red blood cells. Finally, the microdevice was employed to obtain information about the recovery and partition coefficient of invertase from a real complex mixture of proteins (yeast extract) to design a process for the recovery of the enzyme selecting a suitable system and composition to perform the process at bench-scale.

  13. The effect of re-dissolution solvents and HPLC columns on the analysis of mycosporine-like amino acids in the eulittoral macroalgae Prasiola crispa and Porphyra umbilicalis

    Science.gov (United States)

    Karsten, Ulf; Escoubeyrou, Karine; Charles, François

    2009-09-01

    Many macroalgal species that are regularly exposed to high solar radiation such as the eulittoral green alga Prasiola crispa and the red alga Porphyra umbilicalis synthesize and accumulate high concentrations of mycosporine-like amino acids (MAAs) as UV-sunscreen compounds. These substances are typically extracted with a widely used standard protocol following quantification by various high performance liquid chromatography (HPLC) techniques. However, further preparation steps prior to HPLC analysis as well as different HPLC column types have not been systematically checked regarding separation quality and reproducibility. Therefore pure methanol, distilled water and HPLC eluent were evaluated as re-dissolution solvent for dried Prasiola and Porphyra extracts, which were subsequently analyzed on three reversed-phase C8 and C18 HPLC columns. The data indicate that distilled water and the HPLC eluent gave almost identical peak patterns and MAA contents on the C8 and C18 columns. In contrast, the application of the widely used methanol led to double peaks or even the loss of specific peaks as well as to a strong decline in total MAA amounts ranging from about 35% of the maximum in P. crispa to 80% of the maximum in P. umbilicalis. Consequently, methanol should be avoided as re-dissolution solvent for the HPLC sample preparation. An improved protocol for the MAA analysis in macroalgae in combination with a reliable C18 column is suggested.

  14. Quantitative HPLC Analysis of Rosmarinic Acid in Extracts of "Melissa officinalis" and Spectrophotometric Measurement of Their Antioxidant Activities

    Science.gov (United States)

    Canelas, Vera; da Costa, Cristina Teixeira

    2007-01-01

    The students prepare tea samples using different quantities of lemon balm leaves ("Melissa officinalis") and measure the rosmarinic acid contents by an HPLC-DAD method. The antioxidant properties of the tea samples are evaluated by a spectrophotometric method using a radical-scavenging assay with DPPH. (2,2-diphenyl-1-picrylhydrazyl). Finally the…

  15. Quantitative HPLC Analysis of Rosmarinic Acid in Extracts of "Melissa officinalis" and Spectrophotometric Measurement of Their Antioxidant Activities

    Science.gov (United States)

    Canelas, Vera; da Costa, Cristina Teixeira

    2007-01-01

    The students prepare tea samples using different quantities of lemon balm leaves ("Melissa officinalis") and measure the rosmarinic acid contents by an HPLC-DAD method. The antioxidant properties of the tea samples are evaluated by a spectrophotometric method using a radical-scavenging assay with DPPH. (2,2-diphenyl-1-picrylhydrazyl). Finally the…

  16. [Determination of azoxystrobin in tea by HPLC].

    Science.gov (United States)

    Chonan, T

    2001-08-01

    A determination method has been developed for azoxystrobin in tea by HPLC. Azoxystrobin was extracted from a sample with acetone, and the extract was passed through an alumina column to remove tannin. The eluate was concentrated to ca. 25 mL and passed through a Sep-Pak Vac tC18 to remove pigments. The eluate was cleaned-up by using liquid-liquid partition, and Florisil and silica-gel columns. The HPLC analysis for azoxystrobin was carried out on a C18 column with acetonitrile-water (9:11) as the mobile phase, with ultraviolet detection at 260 nm. The recovery of azoxystrobin fortified at the level of 0.4 microgram/g was 90.2% and the limit of determination was 0.2 microgram/g.

  17. HPLC/MS Fingerprint Analysis of Tangshenosides

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Radix codonopsis(党参),which is derived fromCodonopsis pilosula, C.pilosula subsp. Modesta andC. Tangshen(ChP,2000),has been used as a remedy fora decrease of appetite, psychoneurosis, fatigue, dyspepsiaetc.or as a substitute for Panax ginseng in traditionalChinese medicine. Relating to the constituents of theseherbs, triterpenes, phytosterols, furaldehyde, sesquitesand some phenolic glycosides have been reported, butnone of these compounds seems to be responsible for thebiological activities of this drug. As regards the quality evaluation of Radix Codonopsis, a HPLC analysis of atractylenolide Ⅲ has been described, but this sesquiterpene lactone exists in a very low content and is difficultfor conventional analysis. The determination of polysaccharide also met limitation because of its non-specialization. In this paper, we report the HPLC/MS fingerprintsanalysis of phelolic glycosides from Radix Codonopsis including three species.

  18. STABILITY INDICATING HPLC METHOD DEVELOPMENT: A REVIEW

    Directory of Open Access Journals (Sweden)

    Bhoomi P. Shah*, Suresh Jain, Krishna K. Prajapati and Nasimabanu Y. Mansuri

    2012-09-01

    Full Text Available High performance liquid chromatography is one of the most accurate methods widely used for the quantitative as well as qualitative analysis of drug product and is used for determining drug product stability. Stability indicating HPLC methods are used to separate various drug related impurities that are formed during the synthesis or manufacture of drug product. This article discusses the strategies and issues regarding the development of stability indicating HPLC system for drug substance. A number of key chromatographic factors were evaluated in order to optimize the detection of all potentially relevant degradants. The method should be carefully examined for its ability to distinguish the primary drug components from the impurities. New chemical entities and drug products must undergo forced degradation studies which would be helpful in developing and demonstrating the specificity of such stability indicating methods. At every stage of drug development practical recommendations are provided which will help to avoid failures.

  19. Retinoid quantification by HPLC/MS(n)

    Science.gov (United States)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  20. Retinoid quantification by HPLC/MS(n)

    Science.gov (United States)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  1. Automatization for development of HPLC methods.

    Science.gov (United States)

    Pfeffer, M; Windt, H

    2001-01-01

    Within the frame of inprocess analytics of the synthesis of pharmaceutical drugs a lot of HPLC methods are required for checking the quality of intermediates and drug substances. The methods have to be developed in terms of optimal selectivity and low limit of detection, minimum running time and chromatographic robustness. The goal was to shorten the method development process. Therefore, the screening of stationary phases was automated by means of switching modules equipped with 12 HPLC columns. Mobile phase and temperature could be optimized by using Drylab after evaluating chromatograms of gradient elutions performed automatically. The column switching module was applied for more than three dozens of substances, e.g. steroidal intermediates. Resolution (especially of isomeres), peak shape and number of peaks turned out to be the criteria for selection of the appropriate stationary phase. On the basis of the "best" column the composition of the "best" eluent was usually defined rapidly and with less effort. This approach leads to savings in manpower by more than one third. Overnight, impurity profiles of the intermediates were obtained yielding robust HPLC methods with high selectivity and minimized elution time.

  2. An Investigation Into HPLC Data Quality Problems

    Science.gov (United States)

    Hooker, Stanford B.; VanHeukelem, Laurie

    2011-01-01

    This report summarizes the analyses and results produced by a five-member investigative team of Government, university, and industry experts, established by NASA HQ. The team examined data quality problems associated with high performance liquid chromatography (HPLC) analyses of pigment concentrations in seawater samples produced by the San Diego State University (SDSU) Center for Hydro-Optics and Remote Sensing (CHORS). This report shows CHORS did not validate the methods used before placing them into service to analyze field samples for NASA principal investigators (PIs), even though the HPLC literature contained easily accessible method validation procedures, and the importance of implementing them, more than a decade ago. In addition, there were so many sources of significant variance in the CHORS methodologies, that the HPLC system rarely operated within performance criteria capable of producing the requisite data quality. It is the recommendation of the investigative team to a) not correct the data, b) make all the data that was temporarily sequestered available for scientific use, and c) label the affected data with an appropriate warning, e.g., "These data are not validated and should not be used as the sole basis for a scientific result, conclusion, or hypothesis--independent corroborating evidence is required."

  3. Sample preparation and biopharmaceutical analysis

    OpenAIRE

    Farrelly, Gillian

    1998-01-01

    In chapter 1, an overview is given of sample preparation methods and analytical techniques in use today. Each one is discussed, and relevant examples are given. In chapter 2, the development of a method for the HPLC analysis of taurine in human plasma using acetonitrile precipitation and pre-column derivatisation with fluorescamine is presented. This procedure was found to be faster and easier to use than previous taurine assays. In chapter 3, the evaluation of novel aspirin derivativ...

  4. Synthesis and characterization of a multimode stationary phase: Congo red derivatized silica in nano-flow HPLC.

    Science.gov (United States)

    Zhang, Yi; Zhang, Yan; Wang, Guan; Chen, Wujuan; He, Pingang; Wang, Qingjiang

    2016-02-01

    A novel Congo red (CR) derivatized silica stationary phase was prepared and packed into a fused silica capillary tube for nano-flow HPLC. A variety of analytes including poly-aromatic hydrocarbons, parabens, acids, sulfonamides, bases, and nucleosides were successfully separated using the CR. In comparison with commercial ODS columns, this new stationary phase has a different separation mechanism (hydrophobically-assisted ion-exchange), which was evident in the separation of benzoic acid derivatives and sulfonamides. The successful application of CR-bonded silica stationary phase in the HILIC and PALC modes demonstrates the effectiveness of this potential chromatographic material in nano flow HPLC.

  5. Validated HPLC and Ultra-HPLC Methods for Determination of Dronedarone and Amiodarone Application for Counterfeit Drug Analysis.

    Science.gov (United States)

    El-Bagary, Ramzia I; Elkady, Ehab F; Mowaka, Shereen; Attallah, Maria

    2015-01-01

    Two simple, accurate, and precise chromatographic methods have been developed and validated for the determination of dronedarone (DRO) HCl and amiodarone (AMI) HCl either alone or in binary mixtures due to the possibility of using AMI as a counterfeit of DRO because of its lower price. First, an RP-HPLC method is described for the simultaneous determination of DRO and AMI. Chromatographic separation was achieved on a BDS Hypersil C18 column (150×4.6 mm, 5 μm). Isocratic elution based on potassium dihydrogen phosphate buffer with 0.1% triethylamine pH 6-methanol (10+90, v/v) at a flow rate of 2 mL/min with UV detection at 254 nm was performed. The second method is RP ultra-HPLC in which the chromatographic separation was achieved on an AcclaimTM RSLC 120 C18 column (100×2.1 mm, 2.2 μm) using isocratic elution with potassium dihydrogen phosphate buffer with 0.1% triethylamine pH 6-methanol (5+95, v/v) at a flow rate of 1 mL/min with UV detection at 254 nm. Linearity, accuracy, and precision of the two methods were found to be acceptable over the concentration ranges of 5-80 μg/mL for both DRO and AMI. The results were statistically compared using one-way analysis of variance. The optimized methods were validated and proved to be specific, robust, precise, and accurate for the QC of the drugs in their pharmaceutical preparations.

  6. Applying quality by design principles to the small-scale preparation of the bone-targeting therapeutic radiopharmaceutical rhenium-188-HEDP

    NARCIS (Netherlands)

    Lange, Rogier; Ter Heine, Rob; Van Der Gronde, Toon; Selles, Suzanne; De Klerk, John; Bloemendal, Haiko; Hendrikse, Harry

    2016-01-01

    Introduction Rhenium-188-HEDP (188Re-HEDP) is a therapeutic radiopharmaceutical for treatment of osteoblastic bone metastases. No standard procedure for the preparation of this radiopharmaceutical is available. Preparation conditions may influence the quality and in vivo behaviour of this product. I

  7. Chemical characterization of Cuban propolis by HPLC-PDA, HPLC-MS, and NMR: the brown, red, and yellow Cuban varieties of propolis.

    Science.gov (United States)

    Cuesta-Rubio, Osmany; Piccinelli, Anna Lisa; Fernandez, Mercedes Campo; Hernández, Ingrid Márquez; Rosado, Arístides; Rastrelli, Luca

    2007-09-05

    Sixty-five samples of propolis were collected from eleven regions of Cuba; methanolic extracts of propolis were prepared from all samples, and a classification method was developed using a combination of NMR, HPLC-PDA, and HPLC-ESI/MS techniques. The analysis of (1)H and (13)C NMR spectra and chromatographic profiles of all propolis extracts allowed the definition of three main types of Cuban propolis directly related to their secondary metabolite classes: brown Cuban propolis (BCP), rich in polyisoprenylated benzophenones, red Cuban propolis (RCP), containing isoflavonoids as the main constituents, and yellow Cuban propolis (YCP), probably with aliphatic compounds. Subsequently, the principal compounds of the brown and red types were characterized by HPLC-ESI/MS analysis. Instrumental techniques used are complementary; NMR was shown to be a quick and informative tool for the rapid analysis of crude propolis polar extracts and allowed the identification of the main class of secondary metabolites, while LC-PDA and LC-MS techniques were useful tools for qualitative and quantitative analysis of marker compounds of Cuban propolis.

  8. Analysis of clobazam and its active metabolite norclobazam in plasma and serum using HPLC/DAD.

    Science.gov (United States)

    Akerman, K K

    1996-11-01

    This report describes a simple reversed-phase high-performance liquid chromatographic (HPLC) method with automated solid-phase extraction (SPE) for analysing clobazam and norclobazam concentrations in human serum or plasma. For the HPLC analysis the samples and standards are prepared with an ASPEC automatic sample preparer using 100-mg Bond-Elut C-18 solid-phase extraction columns. The HPLC method is an isocratic method with a mobile phase of acetonitrile:methanol:10 mmol l-1 dipotassium hydrogen phosphate, pH 3.7 (30:2:100), at a flow rate of 1.5 ml min-1. The benzodiazepines are detected with a diode array detector (DAD) at 240 nm and the peak purity analyses are performed at 210-365 nm. The recovery is over 97% for both analytes, and it is independent of the drug concentration. The intra-assay CVs vary between 0.7 and 2.2% and inter-assay CVs between 3.8 and 4.6% at therapeutic drug concentrations. The detection limit is 15 nmol l-1. The assay is linear from 30 to 20,000 nmol l-1 (clobazam) and from 170 to 105,000 nmol l-1 (norclobazam). This method leads to a very good separation of norclobazam from carbamazepine and phenytoin. None of the anti-epileptic or antidepressant drugs tested interfere with the assay.

  9. Fea04/PNIPAM纳米复合微球的制备%Preparation of Fe304/PNIPAM Nano-scale Composite-microspheres

    Institute of Scientific and Technical Information of China (English)

    温裕乾; 蔡力锋; 林志勇; 钱浩; 韩惠琴; 林现水

    2012-01-01

    Magnetic Fe304 nanoparticles were prepared by co-precipitation, and further encapsulated with poly(N-isopropylacrylamide) via seeded emulsion polymerization to form Fe3Oa/PNIPAM nano-scale composite-microspheres. The microspheres were characterized by FTIR, TEM, TGA and DTS. Herewith the effects of the concentration of monomer (NIPAM), cross-linker (MBA) and emulsifier (SDBS) on the diameter, magnetic Fe304 content of the microspheres were investigated. The reaction parameters show notable influence on the structure and morphology of the microspheres, and as a result, the diameter and magnetite content of the microspheres decreased with the decrease of monomer concentration and the increase of cross-linker concentration and emulsifier concentration.%用化学共沉淀法制备Fe304磁性纳米粒子,以N-异丙基丙烯酰胺(NIPAM)、N,N’-亚甲基双丙烯酰胺(MBA)和偶氮二异丁腈(AIBN)为原料,用种子乳液聚合法制备了具有温敏性的Fea04/PNIPAM纳米复合微球。用红外光谱仪(FTIR)、透射电镜(TEM)、热重分析仪(TGA)及Zeta粒度仪(DTS)等手段对复合微球进行了表征,研究了单体(NIPAM)、交联剂(MBA)、乳化剂(SDBS)用量对复合微球粒径及磁含量的影响。结果表明:Fea04/PNIPAM纳米复合微球呈球形,具有温敏性,反应条件对复合微球的结构和形貌有较为显著的影响,其粒径和磁含量随着单体浓度的减少、交联剂和乳化剂用量的增加而变小。

  10. Evaluation preparation technology of Xiaochaihu granules using fingerprint-peak pattern matching%Evaluation preparation technology of Xiaochaihu granules using fingerprint-peak pattern matching

    Institute of Scientific and Technical Information of China (English)

    Yu-Qiong Wu; Yu- Qiang Gou; Jing Han; Ying-Yan Bi; Shi-Lan Feng; Fang-Di Hu; Chun- Ming Wang

    2011-01-01

    An approach was proposed to evaluate preparation technology by means of fingerprint-peak matching technology of high performance liquid chromatography with diode array detector (HPLC-DAD). Similarity and hierarchical clustering analysis (HCA) were applied

  11. Formulation and evaluation of freeze-dried DOTMP kit for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP at the hospital radiopharmacy

    Energy Technology Data Exchange (ETDEWEB)

    Das, Tapas; Banerjee, Sharmila [Bhabha Atomic Research Centre, Radiopharmaceuticals Chemistry Section, Mumbai (India); Chakraborty, Sudipta [Bhabha Atomic Research Centre, Isotope Production and Applications Div., Mumbai (India); Sarma, Haladhar D. [Bhabha Atomic Research Centre, Radiation Biology and Health Sciences Div., Mumbai (India)

    2015-07-01

    The objective of the present work is to develop and evaluate freeze-dried DOTMP kit, which could be utilized for the convenient and single-step preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP, both of which have shown potential as alternative agents for metastatic bone pain palliation. Freeze-dried DOTMP kits, each comprising a lyophilized mixture of 20 mg DOTMP and 8.75 mg NaOH, were prepared. The kits were used for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP complexes. The agents were prepared by dissolving the lyophilized powder in 1 mL of normal saline and incubating with {sup 177}LuCl{sub 3} or {sup 153}SmCl{sub 3}, produced in-house, for 15 min at room temperature. Pharmacokinetic behavior and biological distribution of the agents were studied by carrying out biodistribution as well as scintigraphic studies in normal male Wistar rats. Shelf-life of the freeze-dried kits was also ascertained. Clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP complexes, comprising up to 3.7 GBq (100 mCi) of activity, were prepared with > 99% radiochemical purity using the freeze-dried kits. The complexes exhibited high in vitro stability when stored at room temperature. Biological studies showed selective skeletal accumulation and insignificant uptake of the radiotracers in any of the vital organs/tissue. The non-accumulated activity exhibited primary urinary clearance. The kits had a shelf-life of 2 years when stored at 4 C temperature. Freeze-dried DOTMP kits, suitable for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP, have been developed and the radiochemical and biological behaviors of the radiolabeled agents have been studied. The use of the kit at the hospital radiopharmacy is expected to make the preparations easy and convenient. This in turn will enable the widespread dissemination of these promising agents towards their application for regular use.

  12. Determination of cytotoxic compounds of Thai traditional medicine called Benjakul using HPLC.

    Science.gov (United States)

    Itharat, Arunporn; Sakpakdeejaroen, Intouch

    2010-12-01

    Benjakul is a Thai traditional medicine preparation, used for balanced health. From selective interviews of folk doctors in southern Thailand, it was used as the adaptogen drug for cancer patients. In our previous study, the ethanolic extract of Benjakul preparation exhibited high cytotoxic activity against lung cancer cell lines (COR-L23). Piperine has been identified as the main compound in the extract. In addition, plumbagin was found as the most cytotoxic compound. In this study, a reversed-phase high performance liquid chromatography (HPLC) method for quality control such as chemical fingerprint, quantification and stability of the ethanolic extract of Benjakul preparation was developed. The reversed-phase HPLC was performed with a gradient mobile phase composed of water and acetronitrile, and peaks were detected at 256 nm. Based on validation results, this analytical method is precise, accurate and stable for quantitative determination of piperine and plumbagin which are cytotoxic compounds isolated from the ethanolic extract of Benjakul preparation. This method could be suitable for analysis of Benjakul extract.

  13. Comprehensive quality evaluation of Chishao by HPLC

    Directory of Open Access Journals (Sweden)

    Jian Zaiyou

    2013-10-01

    Full Text Available Objective: The purpose of this paper is to comprehensively evaluate the quality of Chishao. Methods: In the experiment of this paper, the fingerprint spectrums of Chishao in all locations are established by RP-HPLC and the model of principle component analysis with the RP-HPLC peak areas is established. Results: The quality of Chishao in the northern part of China or that made of Paeonia lactiflora is better than that of these in others or that made of other species. The quality of Chishao comes from P. veitchii is in the middle class and is better than those that comes from P. obovata, P. mairei and P. anomala. The results are consistent with traditional views of the quality of this plant. These results indicates that principal component analysis (PCA can be used as an effective and economic method to evaluate the quality of Chishao, and may be extended to other Chinese medicinal plants. Conclusions: Due to the complex basis of the efficacy of Traditional Chinese Medicine (TCM, the method such as PCA of several chemical components appears to be a more appropriate method for the quality evaluation of TCM in contrast to the determination of a single or few chemicals.

  14. The comparison of determination of ciprofloxacin by HPLC-UV and HPLC-ELSD%HPLC-UV与HPLC-ELSD测定环丙沙星含量之比较

    Institute of Scientific and Technical Information of China (English)

    乔成孝; 裴朝玉; 陈晓刚; 方国波

    2006-01-01

    目的:探讨利用HPLC-紫外检测器(UV)和HPLC-蒸发光散射检测器(Evaporative light scattering detector, ELSD )测定乳酸环丙沙星氯化钠注射液中环丙沙星含量,比较两种检测方法的优劣.方法:色谱条件为:色谱柱:Kromasil C-18,5μ,250×4.6mm;流动相:三氟乙酸∶乙腈=80∶20(V/V);流速:1mL/min;柱温:25℃;检测波长:277nm;蒸发光散射检测器条件:雾化温度30℃,漂移管温度65℃.结果:环丙沙星注射液中的各种成分在上述色谱条件下能完全分离,分析时间仅需20min;两种测定方法结果一致.结论:紫外检测器更加灵敏和稳定,而蒸发光散射检测器则适用于更多的物质.

  15. HPLC determination of tolperisone in human plasma.

    Science.gov (United States)

    Bae, Jung-Woo; Park, Young-Seo; Sohn, Uy-Dong; Myung, Chang-Sun; Ryu, Byung-Kwon; Jang, Choon-Gon; Lee, Seok-Yong

    2006-04-01

    A simple high performance liquid chromatographic (HPLC) method was developed for the determination of tolperisone in human plasma. Tolperisone and internal standard (chlorphenesin) were isolated from 1 mL of plasma using 8 mL of dichlormethane. The organic phase was collected and evaporated under nitrogen gas. The residue was then reconstituted with 300 mL aliquot of mobile phase and a 100 mL aliquot was injected onto the C18 reverse-phased column. The mobile phase, 45% methanol containing 1% glacial acetic acid and 0.05% 1-hexanesulfonic acid was run at a flow rate of 1 mL/min. The column effluent was monitored using UV detector at 260 nm. The retention times for tolperisone and the internal standard were approximately 7.1 and 8.4 min, respectively. The standard curve was linear with minimal intra-day and inter-day variability. The quantification limit of tolperisone in human plasma was 10 ng/ mL. The proposed method has been applied to the determination of pharmacokinetic profile of tolperisone in Koreans. The Tmax of tolperisone in Koreans (0.94 +/- 0.42 h) was not significantly differ from that reported in Europeans (0.5-1 h), but the mean half-life in Koreans (1.14 +/- 0.27 h) was shorter than that in Europeans (2.56 +/- 0.2 h). The proposed HPLC method is simple, accurate, reproducible and suitable for pharmacokinetic study of tolperisone.

  16. Isolation and identification of arctiin and arctigenin in leaves of burdock (Arctium lappa L.) by polyamide column chromatography in combination with HPLC-ESI/MS.

    Science.gov (United States)

    Liu, Shiming; Chen, Kaoshan; Schliemann, Willibald; Strack, Dieter

    2005-01-01

    A simple method involving polyamide column chromatography in combination with HPLC-PAD and HPLC-ESI/MS for isolating and identifying two kinds of lignans, arctiin and arctigenin, in the leaves of burdock (Arctium lappa L.) has been established. After extraction of burdock leaves with 80% methanol, the aqueous phase of crude extracts was partitioned between water and chloroform and the aqueous phase was fractionated on a polyamide glass column. The fraction, eluting with 100% methanol, was concentrated and gave a white precipitate at 4 degrees C from which two main compounds were purified by semi-preparative HPLC. In comparison with the UV and ESI-MS spectra and the HPLC retention time of authentic standards, the compounds were determined to be arctiin and arctigenin. The extraction/separation technique was validated using an internal standard method.

  17. Evaluation of real-time data obtained from gravimetric preparation of antineoplastic agents shows medication errors with possible critical therapeutic impact: Results of a large-scale, multicentre, multinational, retrospective study.

    Science.gov (United States)

    Terkola, R; Czejka, M; Bérubé, J

    2017-08-01

    Medication errors are a significant cause of morbidity and mortality especially with antineoplastic drugs, owing to their narrow therapeutic index. Gravimetric workflow software systems have the potential to reduce volumetric errors during intravenous antineoplastic drug preparation which may occur when verification is reliant on visual inspection. Our aim was to detect medication errors with possible critical therapeutic impact as determined by the rate of prevented medication errors in chemotherapy compounding after implementation of gravimetric measurement. A large-scale, retrospective analysis of data was carried out, related to medication errors identified during preparation of antineoplastic drugs in 10 pharmacy services ("centres") in five European countries following the introduction of an intravenous workflow software gravimetric system. Errors were defined as errors in dose volumes outside tolerance levels, identified during weighing stages of preparation of chemotherapy solutions which would not otherwise have been detected by conventional visual inspection. The gravimetric system detected that 7.89% of the 759 060 doses of antineoplastic drugs prepared at participating centres between July 2011 and October 2015 had error levels outside the accepted tolerance range set by individual centres, and prevented these doses from reaching patients. The proportion of antineoplastic preparations with deviations >10% ranged from 0.49% to 5.04% across sites, with a mean of 2.25%. The proportion of preparations with deviations >20% ranged from 0.21% to 1.27% across sites, with a mean of 0.71%. There was considerable variation in error levels for different antineoplastic agents. Introduction of a gravimetric preparation system for antineoplastic agents detected and prevented dosing errors which would not have been recognized with traditional methods and could have resulted in toxicity or suboptimal therapeutic outcomes for patients undergoing anticancer treatment.

  18. [Quantitative analysis of nucleosides in four Cordyceps genus by HPLC].

    Science.gov (United States)

    Qian, Zheng-Ming; Li, Wen-Qing; Wang, Chuan-Xi; Zhou, Miao-Xia; Sun, Min-Tian; Gao, Hao; Li, Wen-Jia

    2016-07-01

    To compare the main nucleosides in Cordyceps genus herbs (C. sinensis, C. millitaris, Hirsutella sinensis and C. sobolifera), an HPLC method for simultaneous determination of uridine, inosine, guanosine, adenosine and cordycepine in Cordyceps genus herbs was developed. The sample was extracted with 0.5% phosphoric acid solution to prepare test solution. The separation was performed on a Zorbax SB-Aq (4.6 mm×150 mm, 5 μm) column with gradient elution by 0.04 mol•L⁻¹ potassium dihydrogen phosphate solution and acetonitrile, column temperature 30 ℃,flow rate 0.8 mL•min⁻¹,and detection wavelength 260 nm. The content of nucleosides in four Cordyceps genus herbs was evaluated by fingerprint analysis and hierarchical cluster analysis (HCA). The calibration curves of five nucleosides showed good linear regression (r>0.99) and the average recoveries were between 95.0% and 105.0%. The contents of the five nucleosides in the four Cordyceps genus herbs were different and could be obviously distinguished by HCA. The fingerprint analysis result showed that the similarity between C. sinensis and the others was less than 0.9. The method was accurate and reliable, which can be used for quality control of Cordyceps genus herbs. Copyright© by the Chinese Pharmaceutical Association.

  19. HPLC study of tissue distribution of loganin in rats.

    Science.gov (United States)

    Li, Xiaona; Wang, Qiao; Zhang, Lantong; Xu, Lei; Yin, Wei

    2006-10-01

    A rapid, sensitive and selective high performance liquid chromatography (HPLC) method was developed and validated for determination of loganin in rat tissues. Samples were prepared based on a simple protein precipitation. Separation of loganin was achieved on a reversed-phase C(18) column (250 x 4.6 mm, 5 microm) with a mobile phase consisting of acetonitrile and water (16:84, v/v) at a flow rate of 1.0 mL/min. The detection wavelength was set at 236 nm and the temperature of the column was kept at 30 degrees C. The method was applied to study tissue distribution of loganin in rats after a single administration of loganin at a dose of 20 mg/kg. The highest level was observed in kidney, then in stomach, lung and small intestine. The lowest level was found in brain. The peak levels were attained at 90 min in most tissues. It was indicated that kidney was the major distribution tissue of loganin in rats, and that loganin had difficulty in crossing the blood-brain barrier. It was also found there was no long-term accumulation of loganin in rat tissues.

  20. Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator

    Science.gov (United States)

    Shalliker, R. A.; Kayillo, S.; Dennis, G. R.

    2008-01-01

    Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

  1. Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator

    Science.gov (United States)

    Shalliker, R. A.; Kayillo, S.; Dennis, G. R.

    2008-01-01

    Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

  2. [RP-HPLC characteristics of dragon's blood].

    Science.gov (United States)

    Gao, Xiu-Li; Jiang, Qian; Wang, Peng-Jiao; Zhang, Min

    2007-10-01

    To study the fingerprint of dragon's blood resina draconis by high performance liquid chromatography. The samples are extracted with methanol and separated on a Eclipse XDB-C18 column (4.6 mm x 150 mm, 5 microm) with the mobile phase of acetonitrile-H2O in gradient mode, and the flow rate was 1.0 mL x min(-1), the detection wavelength was 275 nm and the temperature of column was 40 degrees C. Loureirin B was used as the reference compound. HPLC fingerprint of dragon's blood was established and the similarity of the fingerprint was compared. The method is simple, accurate, and can be used to control the quality of dragon's blood.

  3. HPLC METHOD DEVELOPMENT OF AMLODIPINE BY RP-HPLC IN ITS BULK DOSAGE FORMS

    Directory of Open Access Journals (Sweden)

    V. Naveen Kumar, K. Kiran kumar, P. Ramesh Babu, K. Anilkumar

    2012-06-01

    Full Text Available A new, simple, precise, sensitive, accurate and reproducible Reverse phase HPLC method was developed and validated for the analysis of amlodipine in bulk dosage forms. The separation was conducted by using c-18 RP-HPLC coloumn, which was maintained at ambient temperature. The mobile phase consisting of Phosphate buffer and Acetonitrile (90:10v/v was delivered at a rate of 1.5 ml/min. The analysis was detected by using UV detector at the wave length of 225nm.The method is validated for its specificity, precision, accuracy, linearity and robustness. The method was found to be linear over the concentration range 10-100 g/ml (r2 =0.999. The retention time for amlodipine was found to be 3.34min. Limit of quantification of the method is 0.179g/ml and limit of detection is 0.054 g/ml.

  4. The large scale antibacterial, antifungal and anti-phage efficiency of Petamcin-A: new multicomponent preparation for skin diseases treatment.

    Science.gov (United States)

    Ginovyan, Mikayel; Keryan, Andranik; Bazukyan, Inga; Ghazaryan, Petros; Trchounian, Armen

    2015-05-18

    Human and animal skin diseases of bacterial, fungal and viral nature and their complications are widespread and globally cause a serious trouble. Their prevalence is increasing mainly due to drug resistance. Consequently, demand has increased for new effective antimicrobial drugs, which also should be less toxic, possess a wider spectrum of action and be economically more beneficial. The goal was to investigate antibacterial, antifungal and anti-phage activity of Petamcin-A-a new multicomponent preparation. It contains acetic acid and hexamethylenetetramine as main active antimicrobial components, as well as phosphatidylcholine, tocopheryl acetate and glycerol as excipients. Bacteriostatic activity and minimal inhibitory concentrations of the preparation against various test-organisms were determined by agar well diffusion assay. Antifungal activity was tested by agar dilution assay. To explore anti-phage activity double agar overlay plaque assay was used. Nystatin, chlorhexidine and acetic acid were used as control agents for comparative analysis. Statistical analysis was done with GraphPad Prism 5.03 or R 3.1.0 software. The results showed a higher activity of Petamcin-A against all bacterial and fungal test strains compared with its components or control agents. The preparation was more effective against tested gram-positive bacteria than gram-negative ones. Petamcin-A expressed bactericidal activity against almost all test strains. In addition, the preparation demonstrated high activity against T4 phage of Escherichia coli C-T4 completely inhibiting its growth. 5-fold diluted Petamcin-A also exhibited considerable activity reducing phage concentration by 2.6 Log10. Petamcin-A has a high antimicrobial activity against all tested strains of bacteria, yeasts and moulds. The preparation also exhibited high anti-phage activity. Moreover, taking into account that Petamcin-A has no observable toxicity on skin and its components are not expensive, it can be

  5. Reliable HPLC separation, vibrational circular dichroism spectra, and absolute configurations of isoborneol enantiomers.

    Science.gov (United States)

    Gao, Rui-Qi; Fan, Jun; Tan, Qi; Guo, Dong; Chen, Tao; He, Ru-Jian; Li, Dan; Zhang, Hui; Zhang, Wei-Guang

    2017-09-01

    Resolution of chiral compounds has played an important role in the pharmaceutical field, involving detailed studies of pharmacokinetics, physiological, toxicological, and metabolic activities of enantiomers. Herein, a reliable method by high-performance liquid chromatography (HPLC) coupled with an optical rotation detector was developed to separate isoborneol enantiomers. A cellulose tris(3, 5-dimethylphenylcarbamate)-coated chiral stationary phase showed the best separation performance for isoborneol enantiomers in the normal phase among four polysaccharide chiral packings. The effects of alcoholic modifiers and column temperature were studied in detail. Resolution of the isoborneol racemate displayed a downward trend along with an increase in the content of ethanol and column temperature, indicating that less ethanol in the mobile phase and lower temperature were favorable to this process. Moreover, two isoborneol enantiomers were obtained via a semipreparative chiral HPLC technique under optimum conditions, and further characterized by analytical HPLC, and experimental and calculated vibrational circular dichroism (VCD) spectroscopy, respectively. The solution VCD spectrum of the first-eluted component was consistent with the Density Functional Theory (DFT) calculated pattern based on the SSS configuration, indicating that this enantiomer should be (1S, 2S, 4S)-(+)-isoborneol. Briefly, these results have provided reliable information to establish a method for analysis, preparative separation, and absolute configuration of chiral compounds without typical chromophoric groups. © 2017 Wiley Periodicals, Inc.

  6. Monitoring of atrazine in milk using a rapid tube-based ELISA and validation with HPLC.

    Science.gov (United States)

    Barchanska, Hanna; Jodo, Elzbieta; Price, Robert Graham; Baranowska, Irena; Abuknesha, Ramadan

    2012-06-01

    Although atrazine has been banned in the European Union since 2007 it still persists in soil from where it can enter the food chain. Milk-producing animals accumulate atrazine from contaminated feed and water and since large quantities of milk and milk products are consumed its quality should be constantly monitored. The objective of this investigation was to develop a simple tube ELISA procedure suitable for use in non-specialised laboratories and in the field. A polyclonal antibody raised in sheep and the hapten-gelatine conjugate was immobilised onto polystyrene tubes. This enables the colour produced to be read on a basic spectrophotometer. Milk samples were collected from three farms in different regions of Poland and diluted before immunoassay was performed. Samples were extracted with hexane-acetone for HPLC analysis. The amount of fat in the milk samples interferes with the dose response so it essential that the standards are prepared in the same samples matrix. A good correlation between 1% and 2% was found between the two methods in the analysis of real samples. However the ELISA procedure was more sensitive that the HPLC method since atrazine was detected in some samples by the ELISA but was not confirmed by the HPLC method. The study demonstrated that the simple antigen-coated tube assay provides a cost effective and valuable screening test that can be easily modified for direct use as a screening tool in the field. Copyright © 2012. Published by Elsevier Ltd.

  7. Specimen Preservation and Slide Preparation for Newly Hatched Larvae Nymph of Scale Insects%蚧虫初孵若虫采集、保存和玻片标本制作

    Institute of Scientific and Technical Information of China (English)

    赵杰军; 王自力; 陈晓鸣

    2012-01-01

    蚧虫初孵若虫用FAA固定液固定有利于玻片制作和长期保存.在虫体软化、脱水、染色和清洗过程中,使用自制转移虫袋,使得虫体转移更为简易,并可以进行批量处理.用丁香油替代二甲苯、Euparal替代中性树脂或加拿大树胶,使制作过程更具有安全性.%Methods of fixation and slide preparation for newly hatched larvae nymph of scale insects are introduced. FAA fixation is favorable to long-term preservation and slide preparation for newly hatched larvae nymph of scale insets. Self-made bags were used to transfer the insects during maceration, dehydration, coloration, and cleaning, which made larvae transferring easier and mass production possible. The process of slide preparation would be more safety by replacing Canada balsam or neutral resins by euparal and xylene by clove oil, respectively.

  8. HPLC-UV determination of metformin in human plasma for application in pharmacokinetics and bioequivalence studies.

    Science.gov (United States)

    Porta, Valentina; Schramm, Simone Grigoleto; Kano, Eunice Kazue; Koono, Eunice Emiko; Armando, Yara Popst; Fukuda, Kazuo; Serra, Cristina Helena Dos Reis

    2008-01-07

    In this study, a simple, rapid and sensitive HPLC method with UV detection is described for determination of metformin in plasma samples from bioequivalence assays. Sample preparation was accomplished through protein precipitation with acetonitrile and chromatographic separation was performed on a reversed-phase phenyl column at 40 degrees C. Mobile phase consisted of a mixture of phosphate buffer and acetonitrile at flow rate of 1.0 ml/min. Wavelength was set at 236 nm. The method was applied to a bioequivalence study of two drug products containing metformin, and allowed determination of metformin at low concentrations with a higher throughput than previously described methods.

  9. Large-scale preparation of strawberry-like, AgNP-doped SiO2 microspheres using the electrospraying method

    Science.gov (United States)

    Ma, Zhijun; Ji, Huijiao; Tan, Dezhi; Dong, Guoping; Teng, Yu; Zhou, Jiajia; Guan, Miaojia; Qiu, Jianrong; Zhang, Ming

    2011-07-01

    In this paper, we report on a novel strategy for the preparation of silver nanoparticle-doped SiO2 microspheres (Ag-SMSs) with an interesting strawberry-like morphology using a simple and efficient electrospraying method. SEM (scanning electron microscopy), TEM (transmission electron microscopy), XRD (x-ray diffraction), EDS (energy-dispersive spectroscopy) and UV-vis spectra (ultraviolet-visible spectra) were applied to investigate the morphology, structure, composition and optical properties of the hybrid microspheres, and E. coli (Escherichia coli) was used as a model microbe to evaluate their antibacterial ability. The results showed that the Ag-SMSs were environmentally stable and washing resistant. The Ag-SMSs exhibited effective inhibition against proliferation of E. coli, and their antibacterial ability could be well preserved for a long time. The environmental stability, washing resistance, efficient antibacterial ability and simple but productive preparation method endowed the Ag-SMSs with great potential for practical biomedical applications.

  10. A Rapid Reversed-Phase HPLC Method for Analysis of Trans-Resveratrol in PLGA Nanoparticulate Formulation

    OpenAIRE

    Singh, Gurinder; Pai, Roopa S.

    2014-01-01

    A rapid reversed-phase high performance liquid chromatography (RP-HPLC) method was developed for the determination of trans-resveratrol (t-RVT) in PLGA nanoparticle formulation. A new formulation of t-RVT loaded PLGA nanoparticles (NPs) with potential stealth properties was prepared by nanoprecipitation method in our laboratory. The desired chromatographic separation was achieved on a Phenomenex C18 column under isocratic conditions using UV detection at 306 nm. The optimized mobile phase con...

  11. On-line comprehensive two-dimensional normal-phase liquid chromatography × reversed-phase liquid chromatography for preparative isolation of Peucedanum praeruptorum.

    Science.gov (United States)

    Wang, Xin-Yuan; Li, Jia-Fu; Jian, Ya-Mei; Wu, Zhen; Fang, Mei-Juan; Qiu, Ying-Kun

    2015-03-27

    A new on-line comprehensive preparative two-dimensional normal-phase liquid chromatography × reversed-phase liquid chromatography (2D NPLC × RPLC) system was developed for the separation of complicated natural products. It was based on the use of a silica gel packed medium-pressure column as the first dimension and an ODS preparative HPLC column as the second dimension. The two dimensions were connected with normal-phase (NP) and reversed-phase (RP) enrichment units, involving a newly developed airflow assisted adsorption (AAA) technique. The instrument operation and the performance of this NPLC × RPLC separation method were illustrated by gram-scale isolation of ethanol extract from the roots of Peucedanum praeruptorum. In total, 19 compounds with high purity were obtained via automated multi-step preparative separation in a short period of time using this system, and their structures were comprehensively characterized by ESI-MS, (1)H NMR, and (13)C NMR. Including two new compounds, five isomers in two groups with identical HPLC and TLC retention values were also obtained and identified by 1D NMR and 2D NMR. This is the first report of an NPLC × RPLC system successfully applied in an on-line preparative process. This system not only solved the interfacing problem of mobile-phase immiscibility caused by NP and RP separation, it also exhibited apparent advantages in separation efficiency and sample treatment capacity compared with conventional methods.

  12. Selenium speciation and isotope composition in 77Se-enriched yeast using gradient elution HPLC separation and ICP-dynamic reaction cell-MS

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Sloth, Jens Jørgen; Hansen, M.

    2003-01-01

    using the enriched Se-77-selenite as substrate, were released by enzymatic hydrolysis using (I), a beta-glucosidase followed by a protease mixture, and (II), a commercial protease preparation. For selenium speciation the chromatographic selectivity of the cation exchange HPLC system was adjusted...

  13. Comparison of three methods on assay for vitamin A: UV, NP-HPLC and RP-HPLC%测定维生素A的三种方法比较

    Institute of Scientific and Technical Information of China (English)

    钱玲慧; 廖佳宇; 李亚妮; 莫晓帆; 马丽; 姚彤炜

    2012-01-01

    Objective To compare three different methods used in vitamin A determination in soft capsule and to provide reference for the assay of vitamin A and its preparations. Method UV, NP-HPLC and RP-HPLC were chosen in this research. Cyclohexane was used as solvent in the triple wavelength method of UV; Column of NP- HPLC was filled with Hypersil SiO2 (250×4. 6mm.5μm) and the mobile phase consisted of n-hexane and isopropyl alcohol (99. 8 : 0. 2); Column of RP- HPLC was packed with C1H(150×4. 6mm,5μm) and the mobile phase was methanol-water(97 : 3). Results The content of vitamin A determined by UV was 95. 5% , RSD = 1. 3%(n = 5); 112. 5%,RSD= 3.2%(n = 5)by NP-HPLC and 102.3%, RSD= 1. 0%(n = 5) by RP-HPLC. Conclusion Both UV and RP-HPI.C are convenient measurements for vitamin As NP-HPLC shows advantages in the test of impurities, while its stability is relatively poor.%目的:比较测定维生素A含量的3种不同方法,为维生素A及其制剂的质量研究提供参考.方法:分别采用紫外(UV)三点校正法与正、反相高效液相色谱法(HPLC)测定维生素A含量.UV三点校正法以环己烷为溶剂,按照三点校正法测定;NP-HPLC采用Hypersil Si()2柱(250 mm×4.6 mm,5 μm),流动相为正己烷异丙醇(99.8:0.2);RP-HPLC采用C18柱(150 mm×4.6 mm,5 μm),流动相为甲醇-水(97:3).结果:UV三点校正法测得VA含量为95.5%,RSD=1.3%(n=5);NP-HPLC为112.5%,RSD=3.2%(n=5);RP-HPLC为102.3%,RSD=1.0%(n=5).结论:UV三点校正法和RP-HPLC法操作简单易行,NP-HPLC法能较好地控制杂质,但系统稳定性相对较差.

  14. Direct 13C NMR Detection in HPLC Hyphenation Mode

    DEFF Research Database (Denmark)

    Wubshet, Sileshi Gizachew; Johansen, Kenneth; Nyberg, Nils

    2012-01-01

    Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments...... application of HPLC-SPE-NMR analysis using direct-detected (13)C NMR spectra. HPLC column loading, accumulative SPE trappings, and the effect of different elution solvents were evaluated and optimized. A column loading of approximately 600 mug of a prefractionated triterpenoid mixture, six trappings...

  15. Preparation for colonoscopy: types of scales and cleaning products Preparación para colonoscopia: tipos de productos y escalas de limpieza

    Directory of Open Access Journals (Sweden)

    Vicente Lorenzo-Zúñiga

    2012-08-01

    Full Text Available Adequate bowel preparation is essential before a colonoscopy, allowing us to make a proper examination of the entire mucosa. The ideal method of colon cleansing should be fast, safe, and get a proper cleaning with minimal discomfort for the patient. Today we have a wide variety of colon cleansing products, information sometimes becomes confused. A good colon preparation depends partly on correct choice of the same, but also upon dietary restriction. Knowledge of all these products, with their advantages and limitations, we can make a better selection for each patient, and although the efficacy is comparable, is the experience of the browser, patient preferences, and the degree of compliance with the instructions preparation, which greatly influence the results.Una adecuada preparación del colon es fundamental antes de realizar una colonoscopia, ya que nos permite realizar una correcta exploración de toda la mucosa. El método ideal de limpieza del colon debe ser rápido, seguro y conseguir una limpieza apropiada con las mínimas molestias para el paciente. En la actualidad disponemos de una amplia variedad de productos de limpieza de colon, información que en ocasiones llega a ser confusa. Una buena preparación del colon depende por una parte de una correcta elección del mismo, pero también de una restricción dietética previa. El conocimiento de todos estos productos, con sus ventajas y limitaciones, nos permite hacer una mejor selección para cada paciente; y aunque la eficacia sea comparable, es la experiencia del explorador, las preferencias del paciente y el grado de cumplimiento de las instrucciones de preparación, las que influyen notablemente en los resultados.

  16. Analytical standards production for the analysis of pomegranate anthocyanins by HPLC

    Directory of Open Access Journals (Sweden)

    Manuela Cristina Pessanha de Araújo Santiago

    2014-03-01

    Full Text Available Pomegranate (Punica granatum L. is a fruit with a long medicinal history, especially due to its phenolic compounds content, such as the anthocyanins, which are reported as one of the most important natural antioxidants. The analysis of the anthocyanins by high performance liquid chromatography (HPLC can be considered as an important tool to evaluate the quality of pomegranate juice. For research laboratories the major challenge in using HPLC for quantitative analyses is the acquisition of high purity analytical standards, since these are expensive and in some cases not even commercially available. The aim of this study was to obtain analytical standards for the qualitative and quantitative analysis of the anthocyanins from pomegranate. Five vegetable matrices (pomegranate flower, jambolan, jabuticaba, blackberry and strawberry fruits were used to isolate each of the six anthocyanins present in pomegranate fruit, using an analytical HPLC scale with non-destructive detection, it being possible to subsequently use them as analytical standards. Furthermore, their identities were confirmed by high resolution mass spectrometry. The proposed procedure showed that it is possible to obtain analytical standards of anthocyanins with a high purity grade (98.0 to 99.9% from natural sources, which was proved to be an economic strategy for the production of standards by laboratories according to their research requirements.

  17. Comprehensive quality evaluation of Chishao by HPLC.

    Science.gov (United States)

    Zaiyou, Jian; Wenquan, Wang; Guifang, Xu; Li, Meng; Junling, Hou

    2013-01-01

    Objetivo: El propósito de este artículo es la evaluación cualitativa extensa de Chishao. Métodos: En el experimento de este trabajo, se establecen los espectros de identificación de Chishao en todas las localizaciones mediante RP-HPLC y el método del análisis de componentes principales con las áreas pico de RPHPLC. Resultados: La calidad de Chishao en el norte de China o del procedente de Paeonia lactiflora es mejor que la de otras localizaciones o procedente de P. obovata, P. mairei y P. anomala. Los resultados son congruentes con la impresión tradicional de la calidad de esta planta. Estos resultados indican que el análisis de los componentes principales (ACP) puede utilizarse como método eficaz y económico para evaluar la calidad de Chishao y podría aplicarse a otras plantas medicinales chinas. Conclusiones: Dada la complicada base de la eficacia de la Medicina tradicional china (MTC), un método como el ACP para diversos componentes químicos parece ser más adecuado para la evaluación de la calidad de la MTC en comparación con la determinación de un único o unos pocos agentes químicos.

  18. The effects of scaling and root planing on the marginal gap and microleakage of indirect composite crowns prepared with different finish lines: an in vitro study.

    Science.gov (United States)

    Angerame, D; Sorrentino, R; Cettolin, D; Zarone, F

    2012-01-01

    The present in vitro study aimed to assess the effects of root surface mechanical instrumentation on the marginal integrity and adaptation of resin composite crowns. The following null hypotheses were tested: no differences exist between finish line and 1) marginal gap or 2) marginal microleakage before and after manual mechanical periodontal maintenance. A total of 56 intact human mandibular molars were randomly distributed into four groups and subjected to standardized tooth preparations for indirect composite crowns with different marginal finish lines (90° shoulder, beveled 90° shoulder, feather edge, chamfer). One-half of the specimens was used as a control and remained untreated, and the remaining half was subjected to root surface procedures simulating five years of semestral mechanical supportive periodontal treatment. The marginal gap and microleakage were evaluated and statistically analyzed. The specimens used as controls showed lower mean marginal gaps than those subjected to the simulated periodontal treatment, whereas the latter showed lower microleakage than the control crowns. Statistically significant differences were recorded for both the experimental variables. The root surface procedures resulted in altered surfaces of the composite crowns. The marginal gap increased after the treatment, whereas the marginal microleakage was reduced. The 90° shoulder and the chamfer preparation could be considered a viable option to fabricate composite crowns, but the beveled 90° shoulder and the feather edge should not be recommended.

  19. 异硫氰酸苯酯柱前衍生化HPLC测定盐酸氨基葡萄糖的含量%Determination of Glucosamine Hydrochloride (GL-HCl) inCompound Preparations by HPLC withPre-column Phenylisothiocyanate Derivatization

    Institute of Scientific and Technical Information of China (English)

    郝秀华; 韩丛成; 杨锦竹; 张纯海

    2012-01-01

    目的:采用异硫氰酸苯酯柱前衍生化高效液相色谱法测定复方制剂中盐酸氨基葡萄糖的含量.方法:以氨基半乳糖为内标,异硫氰酸苯酯为柱前衍生剂,采用Agilent TC C18(4.6 mm×250mm,5μm)色谱柱,流动相10 mmol· L-1pH 5.8的磷酸盐缓冲液-乙腈(90∶10),检测波长254 nm,流速0.8 mL· min -1,柱温30℃.结果:盐酸氨基葡萄糖质量浓度在350~550 mg·L -1,经衍生化后其衍生物峰面积与内标衍生物峰面积的比值与盐酸氨基葡萄糖浓度呈线性相关(r =0.999 1).制剂中盐酸氨基葡萄糖含量测定的平均回收率98.3% (RSD 2.3%).结论:异硫氰酸苯酯柱前衍生化高效液相色谱法测定结果准确灵敏、方法可靠,适用于复方制剂中等复杂样品中盐酸氨基葡萄糖的含量测定.%Objective: To develop an effective HPLC method based on a reaction of phenylisothiocyanate ( PITC) with glucosamine ( GL) in alkaline media for the determination of glucosamine hydrochloride in dosage forms. Method: Reverse phase chromatography using pre-column derivatization with phenylisothiocyanate, and ultraviolet detection (254 nm) was used to quantify the eluate. The reaction produces a phenylthiocarbamyl-glucosamine (PTC-GL) adduct which was separated on a reverse-phase (RP) column packed with Agilent TC C18 (4. 6 mm×250 mm,5μm). The mobile phase consisted of pH 5. 8 phosphate buffered saline acetonitrile(90 : 10) and was pumped at a flow rate of 0. 8 mL-min' , and the column temperature was maintained at 30℃. Galactosamine hydrochloride (Gal-HC1) was used as an internal standard. Result: The standard curves for GL-HC1 showed linearity ( r = 0. 999 1) over the selected concentration range from 350 to 550 mg·L-1 for dosage forms. The average recoveriy of glucosamine hydrochloride was 98.3% ( RSD 2.3%). Conclusion: The method was found to be specific and with excellent linearity, accuracy and precision and is well suited for the quantitation of GL-HC1 in

  20. Determination of carbonyl compounds in air by HPLC; Determinacion de compuestos carbonilicos en aire por HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.; Perez, R.M.; Campos, A.; Gonzalez, D.

    1995-07-01

    A method for the determination of seven carbonyl compounds in air is presented. The procedure involve sampling of air by a Sep-Pak Cartridge impregnated with 2,4-dinitrophenylhydrazine. Elution was done with 3 mL of acetonitrile and the eluate was diluted to 5 mL. The analysis was done by HPLC with UV detection and external standard method quantification. It has been achieved relative standard deviations about 5% and detection limits of 80 ng/cartridge for formaldehyde, acetaldehyde and acetoacetonitrile. Three different types of samples (rural, urban, petrol emission) were successfully analyzed. (Author) 12 refs.

  1. The identification of markers for Geoforensic HPLC profiling at close proximity sites.

    Science.gov (United States)

    McCulloch, G; Dawson, L A; Brewer, M J; Morgan, R M

    2017-03-01

    Soil is a highly transferable source of trace physical material that is both persistent in the environment and varied in composition. This inherent variability can provide useful information to determine the geographical origin of a questioned sample or when comparing and excluding samples, since the composition of soil is dependent on geographical factors such as climate, bedrock geology and land use. Previous studies have limited forensic relevance due to the requirement for large sample amounts and unrealistic differences between the land use and geographical location of the sample sites. In addition the philosophical differences between the disciplines of earth sciences, for which most analytical techniques have been designed, and forensic sciences, particularly with regard to sample preparation and data interpretation have not been fully considered. This study presents an enhanced technique for the analysis of organic components of geoforensic samples by improving the sample preparation and data analysis strategies used in previous research into the analysis of soil samples by high performance liquid chromatography (HPLC). This study provides two alternative sets of marker peaks to generate HPLC profiles which allow both easy visual comparison of samples and the correct assignment of 100% of the samples to their location of origin when discriminating between locations of interest in multivariate statistical analyses. This technique thereby offers an independent form of analysis that is complementary to inorganic geoforensic techniques and offers an easily accessible method for discriminating between close proximity forensically relevant locations.

  2. HPLC Quantification of Flavonoids and Biflavonoids in Cupressaceae Leaves

    OpenAIRE

    A. Romani; C. GALARDI; P. PINELLI; Mulinacci, N.; D. HEIMLER

    2002-01-01

    The aim of this investigation was to obtain qualitative and quantitative profiles of the flavonoid and biflavonoid composition of six cypress species - Cupressus funebris L., Cupressus semper- Wrens L., Cupressus glabra L., Cupressus arizonica L., Cupressus goveniana L., and Cupressus lusitanica L. HPLC-diode-array detection (DAD), HPLC-MS, and HPTLC were used to identify the individual compounds. A chromatographic method was optimized for identification and quantification of t...

  3. Optimisation of a sol-gel synthesis route for the preparation of MgF2 particles for a large scale coating process.

    Science.gov (United States)

    Scheurell, K; Noack, J; König, R; Hegmann, J; Jahn, R; Hofmann, Th; Löbmann, P; Lintner, B; Garcia-Juan, P; Eicher, J; Kemnitz, E

    2015-12-07

    A synthesis route for the preparation of optically transparent magnesium fluoride sols using magnesium acetate tetrahydrate as precursor is described. The obtained magnesium fluoride sols are stable for several months and can be applied for antireflective coatings on glass substrates. Reaction parameters in the course of sol synthesis are described in detail. Thus, properties of the precursor materials play a crucial role in the formation of the desired magnesium fluoride nanoparticles, this is drying the precursor has to be performed under defined mild conditions, re-solvation of the dried precursor has to be avoided and addition of water to the final sol-system has to be controlled strictly. Important properties of the magnesium fluoride sols like viscosity, particle size distribution, and structural information are presented as well.

  4. Vergelijking van HPLC-methoden voor de bepaling van pentachloorfenol in houtmonsters

    OpenAIRE

    Goewie; C.E.; Berkhoff; Der, C J

    1986-01-01

    Een vergelijkend onderzoek is verricht naar de bruikbaarheid van verschillende detectiemethoden in combinatie met HPLC voor de analyse van pentachloorfenol in hout. In het onderzoek wordt RP-HPLC met UK en amperometrische detectie beschreven, evenals NP-HPLC met elektroneninvangdetectie. In verschillende houtmonsters kon m.b.v. de NP-HPLC met electroneninvangdetectie 1-50 ppm pentachloorfenol worden aangetoond.

  5. Using Large-scale Spatially and Temporally Consistent Reanalysis Data to Assess Fire Weather and Fire Regimes in Siberia in Preparation for Future Fire Weather Prediction

    Science.gov (United States)

    Soja, A. J.; Westberg, D. J.; Stackhouse, P. W.; McRae, D.; Jin, J.

    2008-12-01

    A primary driving force of land cover change in boreal regions is fire, where extreme fire seasons are influenced by local weather and ultimately climate. It is predicted that fire frequency, area burned, fire severity, fire season length, and severe fire seasons will increase under current climate change scenarios. The use of local ground based weather data can be used to gauge the local fire potential on a daily, monthly, or seasonal basis. However, the number and distribution of surface observing stations in Siberia have been declining since the early 1990's. A compounding problem is existing observing stations have missing data on various time scales. The density of stations is limited; hence results may not be representative of the spatial reality. One solution is the temporally and spatially consistent NASA Goddard Earth Observing System version 4 (GEOS-4) satellite-derived weather data interpolated to a 1x1 degree grid. In previous work, we showed the Canadian Forest Fire Weather Index (FWI) derived using GEOS-4 weather and Global Precipitation Climatology Project (GPCP) precipitation data compared well to ground based weather data from Jakutsk (Sakha) and Kyzyl (Tuva), Russia. Our primary focus is to expand on this work by spatially comparing the FWI derived from GEOS-4 / GPCP data and ground-based weather observations from the National Climatic Data Center (NCDC). Extreme fires burned in Sakha and Tuva in 2002 and 2004, respectively, while in contrast, normal fire seasons occurred in Sakha and Tuva in 1999 and 2002, respectively. For this reason, we focus on the 1999, 2002, and 2004 fire seasons (April - September). In this investigation, we demonstrate how fire weather models perform on a large scale and investigate the performance of these models relative to input uncertainties. We intend to use this information to build regional-scale fire predictions systems that can be used for future interactive fire-weather-climate assessments.

  6. The Aerial Regional-Scale Environmental Surveyor (ARES): New Mars Science to Reduce Human Risk and Prepare for the Human Exploration

    Science.gov (United States)

    Levine, Joel S.; Croom, Mark A.; Wright, Henry S.; Killough, B. D.; Edwards, W. C.

    2012-01-01

    Obtaining critical measurements for eventual human Mars missions while expanding upon recent Mars scientific discoveries and deriving new scientific knowledge from a unique near surface vantage point is the focus of the Aerial Regional-scale Environmental Surveyor (ARES) exploration mission. The key element of ARES is an instrumented,rocket-powered, well-tested robotic airplane platform, that will fly between one to two kilometers above the surface while traversing hundreds of kilometers to collect and transmit previously unobtainable high spatial measurements relevant to the NASA Mars Exploration Program and the exploration of Mars by humans.

  7. Preparation and Inhibition Performance of IA-HPEC Copolymer Scale Inhibitor%IA-HPEC共聚物阻垢剂的制备及阻垢性能

    Institute of Scientific and Technical Information of China (English)

    韶晖; 王雅; 周胤; 冷一欣; 钟璟

    2015-01-01

    以异丁烯醇聚氧乙烯醚(H PEG )、衣康酸(IA )为原料,在过硫酸铵-次亚磷酸钠引发剂作用下进行自由基共聚,合成阻垢剂IA-HPEC。采用FT-IR、1 H-NMR等方法表征IA-HPEC阻垢剂结构,采用扫描电镜(SEM )观察阻垢后形成的CaCO3晶体形貌。通过静态阻垢性能实验,考察了单体配比、聚合条件、氧化剂滴加方式及用量对合成的IA-HPEC阻垢剂阻垢性能的影响。结果表明,在 m(IA)/m(HPEC)=1、聚合温度110℃、聚合时间1.5 h、分批滴加氧化剂的最佳聚合条件下,合成的共聚物IA-HPEC对CaCO3的阻垢率为93.9%,优于市场含磷阻垢剂,具有较好的经济与环境效益。%IA-HPEC copolymer was synthesized with itaconic acid (IA ) and isobutylene alcohol ethoxylates (HPEG ) as raw material , ammonium persulfate-sodium hypophosphite as initiator . The product was characterized by FT-IR and 1 H-NMR .The influences of monomer mass ratio , polymerization conditions , oxidant dropping method and dosage on inhibition performance of synthesized IA-HPEC copolymer was investigated by the static scale inhibition experiment . The disordered CaCO3 crystal in the presence of IA-HPEC was analyzed by SEM .The results showed that the IA-HPEC synthesized under the optimal conditions of m (IA )/m ( HPEC ) = 1 , polymerization temperature 110℃ ,polymerization time 1.5 h and oxidant dropping in batches , exhibited excellent ability to control CaCO3 scale , when the inhibition rate on CaCO3 reached 93.9% .The scale inhibiting efficiency of IA-HPEC was better than market inhibitors ,indicating that IA-HPEC had good economic and environmental benefits .

  8. Preparation of Environmentally Friendly Non-phosphorus Corrosion and Scale Inhibitor%环保型无磷缓蚀阻垢剂的制备

    Institute of Scientific and Technical Information of China (English)

    郑兴文; 曾宪光; 龚敏; 金永中

    2012-01-01

    Based on the low molecular weight sodium polyacrylate(PAAS),the corrosion and scale inhibitor with non-phosphorus formula was prepareded by PAAS,sodium molybdate,D-glucose acid sodium,1,2,3-benzotriazole and hexamethylenetetramine in definite proportion.Its anti-scaling performance was evaluated by calcium carbonate deposition method,its corrosion inhibition was evaluated by rotation specimen method and electro chemical method.The best formula is sodium polyacrylate 15 mg/L,D-glucose acid sodium 14 mg/L,1,2,3-benzotriazole 13 mg/L,sodium molybdate 18 mg/L,hexamethylenetetramine 14 mg/L.The scale inhibition efficiency and corrosion inhibition efficiency of the inhibitor were 92.63% and 92.78% respectively.This formula ethibits the characteristics of no phosphorus,non-toxicity,high efficiency and being environmental friendly.There are important economic and use values.%以低分子量聚丙烯酸钠(PAAS)为基础,将聚丙烯酸钠、钼酸钠、D-葡萄糖酸钠、苯并三氮唑、六次甲基四胺等物质按一定比例复配成无磷缓蚀阻垢剂配方,采用碳酸钙沉积法评价其阻垢性能,用旋转挂片法和电化学法评价其缓蚀性能。优选出的最佳缓蚀剂配方为:聚丙烯酸钠15mg/L、D-葡萄糖酸钠14mg/L、苯并三氮唑13mg/L、钼酸钠18mg/L、六次甲基四胺14mg/L,其阻垢率为92.63%,缓蚀率为92.78%。该配方具有无磷、无毒、高效、环保等特点,具有重要的经济和利用价值。

  9. Determination of sotolon content in South African white wines by two novel HPLC-UV and UPLC-MS methods.

    Science.gov (United States)

    Gabrielli, Mario; Buica, Astrid; Fracassetti, Daniela; Stander, Marietjie; Tirelli, Antonio; du Toit, Wessel J

    2015-02-15

    Sotolon has been reported to play an important role in the atypical ageing and aroma character of many wines. A number of analytical techniques for sotolon analysis in wine have been reported, but these often require extensive sample preparation. In this work we report a HPLC-UV method and a novel UPLC-MS method to determine sotolon concentrations in white wines with little sample preparation applied for the first time for the evaluation of sotolon levels in South African wines. The validation showed that the instrumental methods had good accuracy, repeatability and linearity, but the UPLC-MS method proved more sensitive. For both methods, quantification limits were lower than the sotolon odour threshold in wine (10μg/L), 0.86μg/L and 0.013μg/L, for HPLC-UV and UPLC-MS methods, respectively. Sotolon levels in 65 South African white wines were often found to be lower than the reported odour threshold, with the highest concentration being 9.11μg/L. However, for low levels (sotolon not being quantified with the HPLC-UV method, which made the UPLC-MS method more suitable.

  10. Stability-Indicating Related Substances HPLC Method for Droxidopa and Characterization of Related Substances Using LC-MS and NMR.

    Science.gov (United States)

    Kumar, Thangarathinam; Ramya, Mohandass; Arockiasamy Xavier, S J

    2016-11-01

    Stress degradation studies using high-performance liquid chromatography (HPLC) was performed and validated for Droxidopa (L-DOPS). Droxidopa was susceptible to acid hydrolysis (0.1 N HCl), alkaline hydrolysis (0.15 N NaOH) and thermal degradation (105°C). It was found to be resistant to white light, oxidation and UV light exposure (72 h). The thermal, acid and alkali degradation impurities were detected with the retention time (RT) of 12.7, 19.25 and 22.95 min. Our HPLC method detected process impurities (2R,3R)-2-amino-3-(3,4-dihydroxyphenyl)-3-hydroxypropionic acid (Impurity H), N-Hydroxypthalimide (Impurity N), (2R,3S)-2-amino-3-(benzo[d][1,3]dioxol-5-yl)-3-hydroxypropionic acid (Impurity L) and L-threo n-phthaloyl-3-(3, 4-dihydroxyphenyl)-serine (Intermediate) with RTs of 3.48, 15.5, 25.76 and 28.0 min. The related substances were further characterized and confirmed by liquid chromatography-mass spectroscopy (LC-MS), and nuclear magnetic resonance spectroscopy analysis. Our HPLC method detected up to 0.05 µg/mL of Droxidopa with S/N > 3.0 and quantified up to 0.10 µg /mL of Droxidopa with S/N ratio > 10.0. Droxidopa was highly stable for 12 h after its preparation for HPLC analysis. Our newly developed HPLC method was highly precise, specific, reliable and accurate for the analysis of Droxidopa and its related substances.

  11. A Rapid and Sensitive HPLC Method for the Analysis of Celecoxib in Human Plasma: Application to Pharmacokinetic Studies

    Directory of Open Access Journals (Sweden)

    A Ajami

    2008-09-01

    Full Text Available Background and the purpose of the study: A suitable high-performance liquid chromatography (HPLC method for determination of celecoxib levels in plasma is of prime need for the pharmacokinetics and bioequivalence studies of celecoxib preparations. The present study describes a simple, rapid, sensitive, reliable, and economic HPLC method for determination of celecoxib in human plasma which is more feasible than reported celecoxib HPLC assays. Methods: The drug and internal standard were extracted using n-hexane /isoamyl alcohol (97:3 and analyzed on a C18 µ-Bondapak HPLC column with KH2PO4 (0.01M, pH= 4 - acetonitrile (60:40 as the mobile phase, at 260 nm. The method involved simple one-step liquid-liquid extraction procedure with extraction recovery of greater than 90%. Results:  The standard curve covering 0.01-2.0 μg/ml concentration range was linear. The coefficients of variation and relative errors for inter- and intra-day assay ranged from 5.67 to 9.83 and 0.35 to 7.89 %, respectively. Conclusions: HPLC assay was performed isocratically on a reversed-phase column with UV detection. By this method a limit of quantification of 10 ng/ml of a sample size of 0.5 ml is achieved which is comparable or even better than the reported methods. The developed method was applied to the analysis of celecoxib levels in plasma collected from healthy volunteers who participated in a pharmacokinetic study.

  12. Preparation of Chinese Athlete Mental Health Scale%我国运动员心理健康状态量表编制

    Institute of Scientific and Technical Information of China (English)

    李晖; 张忠秋

    2016-01-01

    目的::依据心理健康双因素模型,从积极心理健康和常见心理健康问题两方面入手,编制适用于我国运动员的心理健康状态量表。方法:通过文献研究与开放式问卷调查结果初步形成了运动员心理健康状态的85个项目。对80名运动员进行预测试,通过项目分析和探索性因素分析探索量表的结构。对205名运动员进行正式量表的测试,通过验证性因素分析确定出了比较合理的运动员心理健康状态结构,并编制出了运动员心理健康状态量表。此外,还选取其中40名运动员进行30天后的重测,并且采用症状自评量表( SCL-90)和幸福感指数量表作为校标,对运动员心理健康状态量表进行多指标的信度与效度检验。结果:对运动员心理健康状态的研究可以从“运动员常见心理问题”和“运动员积极心理特征”两个维度进行。其中“运动员常见心理问题”分量表包含“抑郁”、“敌对”、“焦虑”和“躯体化”四个因子;“运动员积极心理特征”分量表包含“意志品质”、“社会适应”和“积极智能”三个因子。运动员常见心理问题分量表结构模型的χ2/df 0.80,CFI>0.90,RMSEA0.90,CFI>0.90,RMSEA0. 80, CFI>0. 90, RMSEA0.90, CFI>0.90, RMSEA<0.08. The Cronbachαcoefficient was 0.813 for Common Mental Disorders, and test-retest reliability coefficient was 0. 918; The Cronbach αcoefficient was 0.615 for Positive Mental Characteristics and test-retest reliability coefficient was 0. 971. Significant correlation (r=0.3~0.8) appeared between Common Mental Disorders and SCL-90. Significant correlation ( r=0. 2~0. 8) appeared between Positive Mental Characteristics and Index of Well-being. Moderate correlations were present between each factor, and they were all lower than the correlations of the sub-scales. Convergent validity and discrimination validity were good for Chinese Athlete Mental Health Scale

  13. Quantitative analysis combined with chromatographic fingerprint for comprehensive evaluation of Xiaoer Chaigui Tuire granules by HPLC-DAD.

    Science.gov (United States)

    Liu, Hong-Ming; Nie, Lei

    2015-01-01

    Quantitative analysis of eight major components combined with chromatographic fingerprint based on high performance liquid chromatography coupled with diode array detector (HPLC-DAD) was developed for the quality evaluation of Xiaoer Chaigui Tuire granules (XCTG), a traditional Chinese medicine (TCM) preparation. Each compound was analyzed by comparing its retention time and UV spectrum of each chromatographic peak with the corresponding retention time and UV spectrum of each standard compound. Baseline separation was achieved on an Agilent Zorbax SB-C18 column with gradient elution of acetonitrile and 0.1% (v/v) phosphoric acid. The developed method was validated by linearity, precision, repeatability, stability and recovery and was subsequently applied to quality evaluation of 12 batches of XCTG with similarity analysis, principal component analysis and cluster analysis. Quantitative analysis combined with HPLC fingerprint could offer an efficient, reliable and practical approach for quality evaluation of XCTG.

  14. Alternative solvents can make preparative liquid chromatography greener

    NARCIS (Netherlands)

    Shen, Y.; Chen, B.; Beek, van T.A.

    2015-01-01

    To make preparative Reversed-Phase High Performance Liquid Chromatography (RP-pHPLC) greener, alternative solvents were considered among others in terms of toxicity, cost, safety, workability, chromatographic selectivity and elution strength. The less toxic solvents ethanol, acetone and ethyl acetat

  15. Effect of Sintering Temperature to Physical, Magnetic Properties and Crystal Structure on Permanent Magnet BaFe12O19 Prepared From Mill Scale

    Science.gov (United States)

    Ramlan; Muljadi; Sardjono, Priyo; Gulo, Fakhili; Setiabudidaya, Dedi

    2017-07-01

    Permanent magnet of Barium hexa Ferrite with formula BaFe12O19 has been made by metallurgy powder method from raw materials : Barium carbonate (BaCO3 E-merck) and Iron Oxide (Fe2O3 from mill scale). Both of raw materials have been mixed with stoichiometry composition by using a ball mill for 24 hours. The fine powder obtained from milling process was formed by using a hydraulic press at pressure 50 MPa and continued with sintering process. The sintering temperature was varied : 1150°C, 1200°C, 1250°C and 1300°C with holding time for 1 hour. The sintered samples were characterized such as : physical properties (bulk density, porosity and shrinkage), magnetic properties (flux density, remanence, coercivity and magnetic saturation) by using VSM and crystal structure by using XRD. According characterization results show that the crystal structure of BaFe12O19 does not change after sintering process, but the grain size tends to increase. The optimum condition is achieved at temperature 1250°C, and at this condition, the sample has characterization such as : bulk density = 4.35 g/cm3, porosity = 1.03% and firing shrinkage = 11.63%, flux density = 681.1 Gauss, remanence (σr) = 20.78 emu/g, coercivity (Hc) = 2058 Oe and magnetic saturation (σs) 45.16 emu/g.

  16. Size-exclusion HPLC provides a simple, rapid, and versatile alternative method for quality control of vaccines by characterizing the assembly of antigens.

    Science.gov (United States)

    Yang, Yanli; Li, Hao; Li, Zhengjun; Zhang, Yan; Zhang, Songping; Chen, Yi; Yu, Mengran; Ma, Guanghui; Su, Zhiguo

    2015-02-25

    The assembly of antigen structure is often crucial to the potency of vaccines. Currently adopted methods like animal testing and ultracentrifugation take long time and are difficult to automate for multiple samples. Here we develop a size-exclusion high-performance liquid chromatography (SE-HPLC) method to characterize the assembly of antigen structure during both manufacturing process and storage. Three important vaccine antigens including inactivated foot and mouth disease virus (FMDV), which is a virus vaccine; and two virus-like particles (VLPs) vaccines involving hepatitis B core antigen (HBcAg) VLPs, and hepatitis B surface antigen (HBsAg) VLPs, were successfully analyzed using commercially available TSK gel columns with pore size above 45nm. Combined with other analytical methods including SDS-PAGE, dynamic light scattering, wavelength scan, and multi-angle laser light scattering, the SE-HPLC method was proven to be a simple, rapid, and reliable tool for antigen particles assembly analysis. Specifically, for FMDV whole virus particle, SE-HPLC was used to analyze 146S content in vaccine preparations and the thermal dissociation of the 146S. For HBcAg-VLPs that are expressed in recombinant Escherichia coli, its expression level during cell culture process was quantitatively monitored by SE-HPLC. The SE-HPLC also showed applicability for quality check of HBsAg vaccine preparations by monitoring the product consistency of different lot number and the product stability during storage. Results shown in this work clearly demonstrated that SE-HPLC method has potential as a versatile alternative technology for control of the final product by both manufacturers and the regulatory agencies.

  17. Methods of preparation and purification of collagen from Pseudosciaena polyactis scales%黄鱼鱼鳞胶原蛋白制备和纯化方法的研究

    Institute of Scientific and Technical Information of China (English)

    王南平; 何兰; 吴文惠

    2008-01-01

    目的 采用缓冲液-醋酸法,模拟中试条件,研究黄鱼鱼鳞胶原蛋白的分离和纯化方法.方法 胶原蛋白的分离主要包括低温清洗、EDTA缓冲液浸泡、酸性缓冲液提取和透析纯化等4个工艺过程,用SDS-PAGE分析胶原蛋白的纯度,用差示扫描量热仪分析黄鱼胶原蛋白的热力学特性.结果 采用该工艺能获得纯净的黄鱼胶原蛋白.最佳工艺参数:浸提温度10℃以下、EDTA缓冲液(pH值7.5)浓度0.5 mol/L、醋酸缓冲液浓度0.5 mol/L、半透膜截流相对分子质量100 000.纯化的黄鱼胶原蛋白在SDS-PAGE上呈现114 000、124 000、200 000 3条谱带,热变性温度为37.7℃.结论 采用该法获得的黄鱼鱼鳞胶原蛋白可用于纯度要求较高的领域使用.%Objective To investigate the method of isolation and purification of collagen from Pseudosciaena polyactis scales with acetic buffer. Methods The preparation of collagen from Pseudosciaena polyactis scales mainly contained the following steps; washing scales with cool water to delete impurity; precipitating Ca2+ soaked by the EDTA buffer; extracting the collagen with acetic buffer; and dialyzing for purification. The purity of collagen was determined by SDS-PAGE and differential scanning cycler (DSC) was used to analyze the thermodynamic character. Results The optimum conditions in this technology were that extracted temperature should be controlled below 10℃, concentration of the EDTA and acetic buffer were both 0.5 mol/L, and molecular weight over 100 000 were prevented by the dialysis-membrane. The prepared collagen showed three clear bands by SDS-PAGE, the molecular weights were 114 000, 124 000 and 200 000, respectively, the thermal denatured temperature was 37. 7℃. Conclusions The isolated collagen from Pseudosciaena polyactis scales could be applied in the field demanding for higher quality.

  18. Estimation of Eletriptan Hydrobromide in Oral Film Dosage Form by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Pavan Kumar Kothapuvari

    2015-11-01

    Full Text Available A simple, precise, rapid and accurate RP-HPLC method was developed for the percentage drug release estimation of Eletriptan Hydrobromide in oral film dosage form. Eletriptan Hydrobromide is used to treat severe migraine headaches and it’s associated to nausea and sensitivity to light. Eletriptan Hydrobromide oral films were prepared by solvent casting method. It is available in market as conventional tablets (Relpax. An Xterra RP18 (150 × 4.6 with 5 microns particle size and the mobile phase, consisting of KH2PO4 and triethylamine in water adjusting the pH-7.0 with o-phosphoric acid: acetonitrile in ratio of 98:2 v/v & acetonitrile: methanol HPLC Grade (80:20 v/v was used as mobile phase in isocratic mode. The flow rate was 1.0 mL/min and the effluents were monitored at 225 nm. The retention time was 7.0 minutes and the detector response was linear in the concentration of 6.60-99.02µg/mL for Eletriptan Hydrobromide. The respective linear regression equation being Y = 11447 X + 5508 for Eletriptan Hydrobromide. The Limit of Detection (LOD and Limit of Quantification (LOQ were not applicable for dissolution parameter. The method was validated by determining its accuracy, precision, linearity and system suitability. The results of the study showed that the proposed RP-HPLC method is simple, rapid, precise, linear and accurate, which is useful for the routine estimation of percentage drug release of Eletriptan Hydrobromide in oral film dosage form.

  19. HPLC identification and determination of myricetin, quercetin, kaempferol and total flavonoids in herbal drugs

    Directory of Open Access Journals (Sweden)

    Svetlana Kulevanova

    2003-05-01

    Full Text Available A new and rapid HPLC method for identification and determination of myricetin, quercetin, kaempferol and total flavonoids in ten herbal drugs of Macedonian origin is presented. Preparation of samples (Uvae ursi folim, Pruni spinosae flos, Sambuci flos, Betulae folim, Primulae flos, Herniariae herba, Centaurii herba, Tiliae flos, Robiniae pseudoacaciae flos, Bursae pastoris herba included hydrolysis of glycosides and extraction of total aglycones with ethyl acetate. HPLC analysis with UV-diode array detection was carried out on RP C18 column, using 5% acetic acid and acetonitrile in agradient elution mode and column temperature of 30 o C. The monitoring of the elution is performed in the whole UV-range and the acquisition of data for quantitative analysis at 367 nm. Screening of the extracts showed presence of quercetin in nine, kaempferol in seven and myricetin in only one sample. The quantitative analysis showed that the content of quercetin ranged from 0.026-0.506 % (m/m, while for kaempferol it was from traces to 1.246 %. Uvaeursi folium and Pruni spinosae flos were rich in content of quercetin (0.482 % and 0.506 %, respectively, while Pruni spinosae flos and Robiniae pseudoaccaciae flos contained the highest amounts of kaempferol (1.246 % and 0.892 %, respectively. Myricetin was identified and determined only in Betulae folium (0.102 %. The content of total flavonoids in the investigated samples expressed in terms of quercetin ranged from 0.040 to 1.680 %. The proposed HPLC method is convenient for use in routine analysis of myricetin, quercetin and kaempferol, as well as for estimation of total flavonoids content in herbal drugs.

  20. Selenosugar determination in porcine liver using multidimensional HPLC with atomic and molecular mass spectrometry.

    Science.gov (United States)

    Lu, Ying; Pergantis, Spiros A

    2009-01-01

    A methodology based on liquid chromatography coupled online with atomic and molecular mass spectrometry was developed for identifying trace amounts of the selenosugar methyl 2-acetamido-2-deoxy-1-seleno-β-D-galactopyranoside (SeGalNAc) in porcine liver, obtained from an animal that had not received selenium supplementation. Sample preparation was especially critical for the identification of SeGalNAc by molecular mass spectrometry. This involved liver extraction using a Tris buffer, followed by sequential centrifugations. The resulting cytosolic fraction was pre-concentrated and the low molecular weight selenium (LMWSe) fraction obtained from a size exclusion column was collected, concentrated, and subsequently analyzed using a tandem dual-column HPLC-ICP-MS system which consisted of strong cation exchange (SCX) and reversed phase (RP) columns coupled in tandem. Hepatocytosolic SeGalNAc was tentatively identified by retention time matching and spiking. Its identity was further confirmed by using the same type of chromatography on-line with atmospheric pressure chemical ionization tandem mass spectrometry operated in the selected reaction monitoring (SRM) mode. Four SRM transitions, characteristic of SeGalNAc, were monitored and their intensity ratios determined in order to confirm SeGalNAc identification. Instrument limits of detection for SeGalNAc by SCX-RP HPLC-ICP-MS and SCX-RP HPLC-APCI-MS/MS were 3.4 and 2.9 μg Se L(-1), respectively. Selenium mass balance analysis revealed that trace amounts of SeGalNAc, 2.16±0.94 μg Se kg(-1) liver (wet weight) were present in the liver cytosol, corresponding to 0.4% of the total Se content in the porcine liver.

  1. Scales, scales and more scales.

    Science.gov (United States)

    Weitzenhoffer, Andre M

    2002-01-01

    This article examines the nature, uses, and limitations of the large variety of existing, so-called, hypnosis scales; that is, instruments that have been proposed for the assessment of hypnotic behavior. Although the major aim of most of the scales ostensively seems to be to assess several aspects of hypnotic states, they are found generally to say little about these and much more about responses to suggestions. The greatest application of these scales is to be found in research, but they also have a limited place in clinical work.

  2. A global seasonal surface ocean climatology of phytoplankton types based on CHEMTAX analysis of HPLC pigments

    Science.gov (United States)

    Swan, Chantal M.; Vogt, Meike; Gruber, Nicolas; Laufkoetter, Charlotte

    2016-03-01

    Much advancement has been made in recent years in field data assimilation, remote sensing and ecosystem modeling, yet our global view of phytoplankton biogeography beyond chlorophyll biomass is still a cursory taxonomic picture with vast areas of the open ocean requiring field validations. High performance liquid chromatography (HPLC) pigment data combined with inverse methods offer an advantage over many other phytoplankton quantification measures by way of providing an immediate perspective of the whole phytoplankton community in a sample as a function of chlorophyll biomass. Historically, such chemotaxonomic analysis has been conducted mainly at local spatial and temporal scales in the ocean. Here, we apply a widely tested inverse approach, CHEMTAX, to a global climatology of pigment observations from HPLC. This study marks the first systematic and objective global application of CHEMTAX, yielding a seasonal climatology comprised of ~1500 1°×1° global grid points of the major phytoplankton pigment types in the ocean characterizing cyanobacteria, haptophytes, chlorophytes, cryptophytes, dinoflagellates, and diatoms, with results validated against prior regional studies where possible. Key findings from this new global view of specific phytoplankton abundances from pigments are a) the large global proportion of marine haptophytes (comprising 32±5% of total chlorophyll), whose biogeochemical functional roles are relatively unknown, and b) the contrasting spatial scales of complexity in global community structure that can be explained in part by regional oceanographic conditions. The results are publically accessible via

  3. Simultaneous determination of potassium guaiacolsulfonate, guaifenesin, diphenhydramine HCl and carbetapentane citrate in syrups by using HPLC-DAD coupled with partial least squares multivariate calibration.

    Science.gov (United States)

    Dönmez, Ozlem Aksu; Aşçi, Bürge; Bozdoğan, Abdürrezzak; Sungur, Sidika

    2011-02-15

    A simple and rapid analytical procedure was proposed for the determination of chromatographic peaks by means of partial least squares multivariate calibration (PLS) of high-performance liquid chromatography with diode array detection (HPLC-DAD). The method is exemplified with analysis of quaternary mixtures of potassium guaiacolsulfonate (PG), guaifenesin (GU), diphenhydramine HCI (DP) and carbetapentane citrate (CP) in syrup preparations. In this method, the area does not need to be directly measured and predictions are more accurate. Though the chromatographic and spectral peaks of the analytes were heavily overlapped and interferents coeluted with the compounds studied, good recoveries of analytes could be obtained with HPLC-DAD coupled with PLS calibration. This method was tested by analyzing the synthetic mixture of PG, GU, DP and CP. As a comparison method, a classsical HPLC method was used. The proposed methods were applied to syrups samples containing four drugs and the obtained results were statistically compared with each other. Finally, the main advantage of HPLC-PLS method over the classical HPLC method tried to emphasized as the using of simple mobile phase, shorter analysis time and no use of internal standard and gradient elution. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Analysis of crude heparin by (1)H NMR, capillary electrophoresis, and strong-anion-exchange-HPLC for contamination by over sulfated chondroitin sulfate.

    Science.gov (United States)

    Keire, David A; Trehy, Michael L; Reepmeyer, John C; Kolinski, Richard E; Ye, Wei; Dunn, Jamie; Westenberger, Benjamin J; Buhse, Lucinda F

    2010-03-11

    We previously published a strong-anion-exchange-high performance liquid chromatography (SAX-HPLC) method for the detection of the contaminant over sulfated chondroitin sulfate (OSCS) in heparin sodium active pharmaceutical ingredient (API). While APIs have been processed to remove impurities, crude heparins contain insoluble material, chondroitin sulfates, heparan sulfate, and proteins that may interfere with the recovery and measurement of OSCS. We examined 500MHz (1)H NMR, capillary electrophoresis (CE), and SAX-HPLC to quantify OSCS in crude heparin. Using our standard API protocol on OSCS spiked crude heparin samples; we observed a weight percent LOD and LOQ for the NMR approach of 0.1% and 0.3%, respectively, while the SAX-HPLC method gave values of 0.03% and 0.09%, respectively. CE data was not amenable to quantitative measurement of OSCS in crude heparin. We developed a modified HPLC sample preparation protocol using crude dissolved at the 100mg/mL level with a 2.5M NaCl solution. This SAX-HPLC approach gave a weight percent LOD of 0.02% and a LOQ of 0.07% and had better performance characteristics than that of the protocol used for APIs.

  5. 山东省男子体操队体育信息服务实践研究%Information services for Shandong gymnastics team preparing for large -scale sporting events

    Institute of Scientific and Technical Information of China (English)

    满晓霞

    2015-01-01

    依据山东省男子体操队伦敦奥运会竞技备战周期的项目布局及夺金任务目标,采用教练访谈、文献资料、实地调研、数理统计等多种方式,为山东省男子体操队开展全方位体育信息咨询服务,涉及运动训练信息、对手情报信息、参赛环境情报等诸多方面。一方面,在备战大型综合性运动会中进行了体育信息服务模式的积极探索;另一方面,也为管理部门及教练员、运动员科学备战参赛提供信息依据和智力支持。%In preparation for large -scale sporting events,sports information service is of much help for sports authorities to make macro strategies and develop scientific decisions.The Olympic Games is a typical representative of large -scale sporting events.Therefore,taking Shandong Province preparing for the London Olympics as an example,with the methods of literature review,interviews with experts,investigation teams,video analysis,statistics and so on,the paper discussed how the information were gathered,processed and transmitted,and explored its application benefits.

  6. VERIFICATION HPLC METHOD OF QUANTITATIVE DETERMINATION OF AMLODIPINE IN TABLETS

    Directory of Open Access Journals (Sweden)

    Khanin V. A

    2014-10-01

    a volume of 100.0 ml. Preparation of the working standard solution sample amlodipine besylate. 50.0 mg of amlodipine RCC dissolved in methanol and dilute with the same solvent to 50.0 ml. 5.0 ml of this solution argue with methanol to volume 100.0 ml. Before the major controlled trials validated the existence of documents certifying the suitability vykorystovanoho equipment, raw materials and chemicals. Validation of the methodology was carried out in accordance with the requirements of SPhU. Results & discussion. Linearity methods defined within 80-120% of nominal concentrations. The linearity of the methods supported by the entire range of concentrations studied (b=0.9845, Sb=0,01473, a=1.5282, Sa=1.4956, S0=0.5486, r=0.9992. It is proved that the validated method characterized by sufficient convergence and accuracy over the entire range of concentrations (ΔZ=1.03, δ%=0.09. Conclusion. During verification methods of quantitative determination of amlodipine besylate tablets were studied characteristics validated HPLC method: accuracy, linearity, precision, specificity, and internal laboratory precision. Validation technique characteristics do not exceed the critical value of error (1.6% and characterized by qualitative analytical indicators. This technique can be correctly reproduced in the laboratory conditions, and is independent of the excipients.

  7. Variance-based Sensitivity Analysis of Large-scale Hydrological Model to Prepare an Ensemble-based SWOT-like Data Assimilation Experiments

    Science.gov (United States)

    Emery, C. M.; Biancamaria, S.; Boone, A. A.; Ricci, S. M.; Garambois, P. A.; Decharme, B.; Rochoux, M. C.

    2015-12-01

    Land Surface Models (LSM) coupled with River Routing schemes (RRM), are used in Global Climate Models (GCM) to simulate the continental part of the water cycle. They are key component of GCM as they provide boundary conditions to atmospheric and oceanic models. However, at global scale, errors arise mainly from simplified physics, atmospheric forcing, and input parameters. More particularly, those used in RRM, such as river width, depth and friction coefficients, are difficult to calibrate and are mostly derived from geomorphologic relationships, which may not always be realistic. In situ measurements are then used to calibrate these relationships and validate the model, but global in situ data are very sparse. Additionally, due to the lack of existing global river geomorphology database and accurate forcing, models are run at coarse resolution. This is typically the case of the ISBA-TRIP model used in this study.A complementary alternative to in-situ data are satellite observations. In this regard, the Surface Water and Ocean Topography (SWOT) satellite mission, jointly developed by NASA/CNES/CSA/UKSA and scheduled for launch around 2020, should be very valuable to calibrate RRM parameters. It will provide maps of water surface elevation for rivers wider than 100 meters over continental surfaces in between 78°S and 78°N and also direct observation of river geomorphological parameters such as width ans slope.Yet, before assimilating such kind of data, it is needed to analyze RRM temporal sensitivity to time-constant parameters. This study presents such analysis over large river basins for the TRIP RRM. Model output uncertainty, represented by unconditional variance, is decomposed into ordered contribution from each parameter. Doing a time-dependent analysis allows then to identify to which parameters modeled water level and discharge are the most sensitive along a hydrological year. The results show that local parameters directly impact water levels, while

  8. UV- VIS Spectroscopic and HPLC Studies on Dictyota bartayresiana Lamour

    Institute of Scientific and Technical Information of China (English)

    Johnson Marimuthu Antonisamy; Krishnaveni Eahamban

    2012-01-01

    Objective: The present study was aimed to explore phytochemical constituents present in Dictyota bartayresiana Lamour and produce the UV-VIS and HPLC spectrum profile for Dictyotabartayresiana. Methods: Phytochemical screening of the extracts was carried out according to the standard methods. For the HPLC analysis, the methanol: water (45:55) was used as mobile phase. Results: The phytochemical results showed the presence of alkaloids, steroids, phenolic groups, saponins, tannins, glycosides and sugars. The UV- VIS profile of methanolic, petroleum ether, chloroform, isopropanol of D. bartayresiana extract showed various peaks with different functional groups. The HPLC profile of D. bartayresiana petroleum ether, chloroform and benzene extracts showed some prominent and moderate peaks with different retention time. Conclusions:The results of the present study showed that Dictyota bartayresiana Lamour may be rich sources of phytoconstituents which can be isolated and further screened for different kinds of biological activities, depending on their reported therapeutic uses.

  9. Simultaneous determination of olanzapine and fluoxetine hydrochloride in capsules by spectrophotometry, TLC-spectrodensitometry and HPLC.

    Science.gov (United States)

    Tantawy, Mahmoud A; Hassan, Nagiba Y; Elragehy, Nariman A; Abdelkawy, Mohamed

    2013-03-01

    This paper describes sensitive, accurate and precise spectrophotometric, TLC-spectrodensitometric and high performance liquid chromatographic (HPLC) methods for simultaneous determination of olanzapine and fluoxetine HCl. Two spectrophotometric methods were developed, namely; first derivative (D (1)) and derivative ratio (DD (1)) methods. The TLC method employed aluminum TLC plates precoated with silica gel GF254 as the stationary phase and methanol:toluene:ammonia (7:3:0.1, by volume) as the mobile phase, where the chromatogram was scanned at 235 nm. The developed HPLC method used a reversed phase C18 column with isocratic elution. The mobile phase composed of phosphate buffer pH 4.0:acetonitrile:triethylamine (53:47:0.03, by volume) at flow rate of 1.0 mL min(-1). Quantitation was achieved with UV detection at 235 nm. The methods were validated according to the International Conference on Harmonization (ICH) guidelines. The selectivity of the proposed methods was tested using laboratory-prepared mixtures. The developed methods were successfully applied for the determination of olanzapine and fluoxetine HCl in bulk powder and combined capsule dosage form.

  10. A NOVEL STABILITY INDICATING HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF GUAIPHENESIN, CHLORPHENERAMINE MALEATE & DEXTROMETHORPHAN HBr

    Directory of Open Access Journals (Sweden)

    Tarun Goyal

    2013-11-01

    Full Text Available An isocratic HPLC method with UV detection at 225nm is described for simultaneous determination of Guaiphenesin, Chlor-pheneramine Maleate & Dextromethorphan HBr. Chromatographic separation of all three drugs were achieved on Purospher star RP-18e column (Merck using Mobile phase as 74% Buffer (prepared by dissolving 1.8g dipotassium hydrogen orthophosphate in 1 litre of HPLC grade water, adjusting pH-3 with phosphoric acid & 26% Acetonitrile. Method offers simplicity, good linearity, symmetric peak shape, and good resolution is achieved in a run time of 13 minutes. The method has been validated for Specificity, Linearity, Accuracy, and Precision. Stress testing which covered Oxidation, acid and alkali hydrolysis, photolysis and thermal degradation was performed on individual molecules under test to prove the specificity of the method and the degradation products formed were resolved effectively. It has a very good linearity with correlation coefficient value more than 0.999, % recovery for Guaiphenesin, Chlorpheneramine Maleate & Dextromethorphan HBr obtained were between 99-101%, and the relative standard deviation for 5 replicates obtained was less than 0.5%.

  11. VALIDATION OF ABACAVIR SULFATE IN PHARMACEUTICAL DOSAGE BY REVERSE PHASE HPLC WITH INTERNAL STANDARD METHOD

    Directory of Open Access Journals (Sweden)

    Battula Sreenivasa Rao

    2012-08-01

    Full Text Available A rapid, specific and accurate isocratic HPLC method was developed and validated for the assay of abacavir sulfate in pharmaceutical dosage forms. The assay involved an isocratic – elution of abacavir sulfate in Grace C18 column using mobile phase composition consists of (38:62 v/v of methanol and 10ml of potassium dihydrogen orthophosphate. The wavelength of detection is 255nm.The method showed good linearity in the range of 10-50.0mg/mL. The runtime of the method is 8 mins. The proposed method can be used for routine quality control samples in industry in bulk and in finished dosage forms. In present study, a rapid specific precise and validated HPLC method for the quantitative estimation of abacavir sulfate in pharmaceutical dosage forms has been reported. The developed method can be applied to directly and easily to the analysis of the pharmaceutical tablet preparations. The percentage recoveries were near 100% for given methods. The method was completely validated and proven to be rugged. The excipients did not interfere in the analysis. The results showed that this method can be used for rapid determination of abacavir sulfate in pharmaceutical tablet with precision, accuracy and specificity.

  12. Simultaneous quantification of 19 ginsenosides in black ginseng developed from Panax ginseng by HPLC-ELSD.

    Science.gov (United States)

    Sun, Bai-Shen; Gu, Li-Juan; Fang, Zhe-Ming; Wang, Chun-yan; Wang, Zhen; Lee, Mi-Ra; Li, Zheng; Li, Jing-Jie; Sung, Chang-Keun

    2009-08-15

    A high-performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD) has been developed to identify and quantify 19 ginsenosides (Rg(1), Re, Rf, Rb(1), Rc, Rb(2), Rd, F(4), Rg(6), Rk(3), Rh(4), 20(S)-, 20(R)-Rg(3), 20(S)-, 20(R)-Rs(3), Rk(1), Rg(5), Rs(4), and Rs(5)) in black ginseng (BG, Korean white ginseng that was subjected to nine cycles of steam treatment). Ultrasonication is employed for sample preparation, and the analysis is achieved on a Discovery C(18) column using gradient elution of CH(3)CN-H(2)O-CH(3)COOH without buffer in 40min. The method was validated by linearity (r(2)> or =0.9994), precision (92.0-107.5%), intra- and inter-day accuracy (R.S.D.<3.21%), and limit of detection (LOD< or =93ng). The quantification method was applied to analyze the composition of ginsenosides in Korean white, red, and black ginsengs. During the preparatory process of BG, ginsenosides transform into constituents of low polarity by hydrolysis, isomerization, and dehydration at C-20, and hydrolysis also occurs at C-3 or C-6. The validated HPLC method is expected to provide the basis for the quality assessment of ginseng products.

  13. Investigation of contribution of individual constituents to antioxidant activity in herbal drugs using postcolumn HPLC method.

    Science.gov (United States)

    Raudonis, Raimondas; Jakstas, Valdas; Burdulis, Deividas; Benetis, Raimondas; Janulis, Valdimaras

    2009-01-01

    The most important attention is paid to the search of natural antioxidants and their evaluation in medicinal and food raw materials of plant origin. A number of plants, their extracts, food products, and medicinal preparations appear to be the objects of scientific research. Effectiveness and informative character of research, undoubtedly, depend on relevance, sensitivity, and efficiency of the methods chosen. The aim of this work was to develop and validate the postcolumn high-performance liquid chromatography (HPLC)-DPPH method as well as its application in the evaluation of antioxidant activity of known and unknown compounds scavenging free radicals and existing in medicinal plant raw materials. HPLC-separated compounds were identified at the wavelength of 275 nm, and then the mobile phase with analytes flowed through a mixing tee to the reaction coil, where DPPH reagent solution was supplied. The solution flow rate was 0.4 mL/min. The reaction coil was connected with UV/VIS type detector, which measured absorption of flowing solution at the wavelength of 520 nm. It was determined that vitexin rhamnoside, the dominant compound in the leaves of Crataegus monogyna, was not a significant radical scavenger. The most active antioxidant in the leaves and flowers of Crataegus monogyna was chlorogenic acid. The most active antioxidant in Origanum vulgare raw material was rosmarinic acid. Identified analytes in the extracts of Achillea millefolium that possessed radical-scavenging properties were chlorogenic acid, luteolin-7-O-glucoside, rutin, and luteolin.

  14. 罗非鱼鱼鳞粉直接酶解制备胶原蛋白的工艺研究%Study on Preparation of Collagen by Enzymolysis of Tilapia Scale Powder with Alcalase

    Institute of Scientific and Technical Information of China (English)

    孙宪迅; 孙齐英; 韩雪; 周理红

    2012-01-01

    The preparation of collagen by enzymolysis of tilapia scale powder with alcalase was studied in this paper. With extraction rate of collagen as index, the optimum enzymolysis conditions were obtained through single factor experiment and orthogonal experiment as follows:the mass fraction of 100 mesh tilapia scale powder was 7%,enzymolysis temperature was 65 'C .enzymolysis pH value was 8. 5,alcalase amount was 0. 05 AU · G-1,enzymolysis time was 2. 0 h. Under above conditions,the extraction rate of collagen reached 95. 79%.%研究了罗非鱼鱼鳞粉直接酶解制备胶原蛋白的工艺条件.以胶原蛋白提取率为考核指标,采用单因素实验和正交实验确定最佳酶解条件为:100目罗非鱼鱼鳞粉质量分数7%、酶解温度65℃、酶解pH值8.5、酶加量0.05 AU ·g-1、酶解时间2.0h,在此条件下,胶原蛋白提取率达95.79%.

  15. A New HPLC Method to Determine Carbonyl Compounds in Air

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper, a new HPLC method was established to determine the carbonyl compounds in air. As the absorbent, 2, 4-dinitrophenylhydrazine (2, 4-DNPH) reacted with carbonyls specifically, which form the corresponding 2,4-dinitrophenylhydrazones, then analyzed by HPLC. The chromatographic conditions, the recovery rate, stability of samples, reagent blank, sampling efficiency were all studied systematically. The results showed that this established method had high sensitivity and good selectivity compared with other analytical methods, and it can determine ten carbonyl compounds in air in 26 min simultaneously.

  16. Analysis of limette and bergamot distilled essential oils by HPLC.

    Science.gov (United States)

    Buiarelli, Francesca; Cartoni, Giampaolo; Coccioli, Franco; Jasionowska, Renata; Mazzarino, Monica

    2002-04-01

    This work examines the distilled essential oils of limette and bergamot in order to assess the presence of low volatile substances such as coumarins (bergapten) which, being toxic, must be eliminated before using these oils in the food industry. The quantitative determination of coumarins was carried out by spectrofluorimetric detection. The substances present in the chromatograms, obtained by HPLC with UV detection at 254 nm, were then identified. Moreover, a new coumarin that is present in small quantities was identified using HPLC-MS.

  17. Efficiency comparison of preparing nano-scale microbubbles by oscillation and sonication%机械振荡法与声振法制备纳米级微泡超声造影剂效能比较

    Institute of Scientific and Technical Information of China (English)

    郑剑; 王平; 尹庭辉; 郑博文; 程度; 郑荣琴

    2012-01-01

    目的 比较机械振荡法与声振法制备纳米级微泡超声造影剂(Nanobubbles,NBs)的效能.方法分别用机械振荡法和声振法制备NBs,比较两种方法制备NBs的粒径、粒径分布、浓度以及制备所耗时间等.结果 声振法与机械振荡法制备的NBs粒径分别为(373.88±18.43)nm、(360.74±14.39)nm,二者比较差异无统计学意义(P=0.523).声振法制备的NBs离心纯化前粒径分布较广,与机械振荡法制备的NBs粒径分布(分散系数,polidispersity值)比较差异有统计学意义(P<0.001).机械振荡法制备的NBs浓度为(1.48±0.15)×1010,明显高于声振法制备的NBs浓度[(8.07±0.62)×108] (P<0.001).声振法制备NBs较机械振荡法耗时长,两者比较差异有统计学意义(P<0.001).结论 机械振荡法与声振法均能制备出NBs,但与声振法相比,机械振荡法制备的NBs粒径分布窄,浓度高,用时短,可更加快速有效地制备NBs,适合进行肿瘤超声造影成像方面的实验研究.%Objective To compare the efficiency of oscillation with sonication in preparing nano-scale microbubbles (NBs).Methods Nano-scale microbubbles were prepared using oscillation and sonication respectively,and then compared the NBs' size,size distribution,concentrations and time-consumption of the two methods.Results The sizes of nanobubbles prepared by sonication and oscillation were (373.88 ±18.43)nm and (360.74 ± 14.39)nm,respectively.There was no significant difference in size between the two methods (P =0.523).The polidispersity was larger in sonication before centrifugation,there was significant difference between the two methods (P <0.001).The concentration of nanobubbles prepared by oscillation was (1.48 ± 0.15) × 1010,which was higher than that by oscillation [(8.07 ± 0.62) × 108],there was significant difference between the two methods (P < 0.001).The consuming time was shorter in oscillation,the difference was significant when compared with sonication (P

  18. Determination of vitamins D2 and D3 in selected food matrices by online high-performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS).

    Science.gov (United States)

    Nestola, Marco; Thellmann, Andrea

    2015-01-01

    An online normal-phase liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS) method was developed for the determination of vitamins D2 and D3 in selected food matrices. Transfer of the sample from HPLC to GC was realized by large volume on-column injection; detection was performed with a time-of-flight mass spectrometer (TOF-MS). Typical GC problems in the determination of vitamin D such as sample degradation or sensitivity issues, previously reported in the literature, were not observed. Determination of total vitamin D content was done by quantitation of its pyro isomer based on an isotopically labelled internal standard (ISTD). Extracted ion traces of analyte and ISTD showed cross-contribution, but non-linearity of the calibration curve was not determined inside the chosen calibration range by selection of appropriate quantifier ions. Absolute limits of detection (LOD) and quantitation (LOQ) for vitamins D2 and D3 were calculated as approximately 50 and 150 pg, respectively. Repeatability with internal standard correction was below 2 %. Good agreement between quantitative results of an established high-performance liquid chromatography with UV detection (HPLC-UV) method and HPLC-GC-MS was found. Sterol-enriched margarine was subjected to HPLC-GC-MS and HPLC-MS/MS for comparison, because HPLC-UV showed strong matrix interferences. HPLC-GC-MS produced comparable results with less manual sample cleanup. In summary, online hyphenation of HPLC and GC allowed a minimization in manual sample preparation with an increase of sample throughput.

  19. Preparation of Sulfuric Acid Sulfonated Modified Starch and Testing Study of Its Scale Inhibition Properties%硫酸磺化改性淀粉制备及阻垢性能试验研究

    Institute of Scientific and Technical Information of China (English)

    刘玉玲; 高升; 刘利

    2011-01-01

    为了减轻和避免目前阻垢剂排放对环境造成的污染,本实验利用浓硫酸氧化淀粉制备改性淀粉,其颜色为棕红色;在不同浓度、温度、Ca2+浓度、pH值下,对硫酸磺化改性淀粉的阻垢性能进行测试.实验结果表明,硫酸磺化改性淀粉高效阻垢的最佳浓度为0.61 mg/L,最佳温度为80℃,对应的阻垢效率为84.7%.其阻垢效率随着Ca2+浓度及pH值的增加而减小,因此Ca2+浓度、pH值是影响阻垢剂阻垢效率的重要因素.对硫酸磺化改性淀粉与其它氧化改性淀粉的阻垢性能进行的比较实验结果表明,硫酸磺化改性淀粉的阻垢性能优于其它改性淀粉.%In order to mitigate and avoid current scale inhibitor pollution emissions on the environment, in this lab, the concentrated sulfuric acid oxidized starch is used to prepare the modified starch, whose color is brown-red.Sulfuric acid sulfonated modified starch is tested in case of different concentrations, temperatures, Ca2+ concentrations, pH values.It has been found that the best concentration of efficient scale of sulfuric acid sulfocated modified starch is 0.61 mg/L, and that the best temperature is 80 ℃, and that under this best concentration and temperature the corresponding inhibition rate is 84.7 %.The inhibition rate of sulfuric acid sulfonated modified starch decreases with an increase in Ca2+ concentration and pH value, thus, indicating that Ca2+ concentration and pH are the important factors that can affect the inhibition rate of scale inhibitor.Finally, the comparison is made of scale performance between sulfuric acid sulfonated modified starch and other oxidized modified starch, with the results showing that the scale inhibition of sulfuric acid sulfonated modified starch is superior to other oxidized modified starch.

  20. Rapid analysis of components in Rhizoma Anemarrhenae by HPLC-DAD-MS and HPLC-DAD-TOFMS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A global quality control method based on high performance liquid chromatography(HPLC)coupled with diode array detection(DAD),single quadrupole mass spectrometry(MS)and time-of-flight mass spectrometry(TOFMS)was developed for simultaneous determination of seven major components(mangiferin,neomangiferin,timosaponin E1,timosaponin E,timosaponin BⅡ,timosaponin BⅢ,and timosaponin AⅢ)and identification of most components in extracts of Rhizoma Anemarrhenae(RA).HPLC analysis was performed on an Agilent SB-C18 colu...

  1. Analysis of Bovine Serum Albumin Ligands from Puerariae flos Using Ultrafiltration Combined with HPLC-MS

    Directory of Open Access Journals (Sweden)

    Ping Tang

    2015-01-01

    Full Text Available Rapid screening techniques for identification of active compounds from natural products are important not only for clarification of the therapeutic material basis, but also for supplying suitable chemical markers for quality control. In the present study, ultrafiltration combined with high performance liquid chromatography-mass spectrometry (HPLC-MS was developed and conducted to screen and identify bovine serum albumin (BSA bound ligands from Puerariae flos. Fundamental parameters affecting the screening like incubation time, BSA concentration, pH, and temperature were studied and optimized. Under the optimum conditions, nine active compounds were identified by UV and MS data. The results indicated that this method was able to screen and identify BSA bound ligands form natural products without the need of preparative isolation techniques. Moreover, the method has more effective with easier operation procedures.

  2. Comparative performances of selected chiral HPLC, SFC, and CE systems with a chemically diverse sample set.

    Science.gov (United States)

    Borman, Phil; Boughtflower, Bob; Cattanach, Kaye; Crane, Kathy; Freebairn, Keith; Jonas, Greg; Mutton, Ian; Patel, Asha; Sanders, Matt; Thompson, Duncan

    2003-01-01

    Pharmaceutical companies have a continuous need to resolve new racemates. Analysis may be required in aqueous and nonaqueous media, or in the presence of several different sets of potentially interfering compounds. There is often a preparative requirement. For these reasons analysts may require a number of different separation systems capable of resolving a given pair of enantiomers. We wished to improve upon existing approaches that address this situation and undertook a program of work to screen over 100 racemates, selected for their chemical diversity, on over 100 different chiral HPLC, SFC, and CE systems. Here we report results of this comparison and illustrate the use of rapid gradient screening as a valuable tool for chiral method development.

  3. RP-HPLC analysis of Jirakadyarishta and chemical changes during fermentation.

    Science.gov (United States)

    Lal, Uma Ranjan; Tripathi, Shailendra Mani; Jachak, Sanjay M; Bhutani, Kamlesh Kumar; Singh, Inder Pal

    2010-11-01

    Jirakadyarishta, an Ayurvedic formulation prepared by the fermentation of a decoction of Cuminum cyminum (seeds) is traditionally used for intestinal disorders. RP-HPLC analysis of the decoction and the final processed formulation revealed that apigenin-7-O-[galacturonide (1 --> 4)-O-glucoside] and luteolin-4'-O-glucoside-7-O-galacturonide) were the two major constituents of the decoction of C. cyminum. Selective hydrolysis of 7-O-glucosides of luteolin and apigenin during fermentation resulted in an increase in the amount of luteolin and apigenin. The 4'-O-glucoside-7-O-galacturonide of luteolin and galacturonide derivative of apigenin were not hydrolyzed during fermentation. Monomeric phenolics, together with 5-hydroxymethyl furfural (5-HMF), were also introduced into the formulation through the jaggery and other plant materials during fermentation. This communication highlights the importance of the ancient processing methods used in Ayurveda.

  4. Quantitative HPLC of pigments of irregularly coloured eggshells: application to aliquots of powdered shell from quail.

    Science.gov (United States)

    Gorchein, A

    2012-12-01

    Twelve quail eggshells from farmed Coturnix coturnix japonica were separately ground to fine powder and two aliquots of each (average weights 13.86 mg and 51.90 mg) were extracted with formic acid. Biliverdin (38-284 pmol/mg) and protoporphyrin (841-1666 pmol/mg) were measured by HPLC. There was good agreement between the values for the corresponding samples and with those for two entire eggshells from the same source. The preparation of a homogenate as a powder from heterogeneously pigmented eggshells has the advantage that not all of the sample needs to be initially extracted for analysis and residual material can be stored in a stable form and used for repeat measurements and for longitudinal studies.

  5. Determination of Interfacial Parameters of Copolyamide Membrane Material by HPLC

    Institute of Scientific and Technical Information of China (English)

    张秀真; 高素莲; 陈均

    2003-01-01

    The High Performance Liquid Chromatography (HPLC) method is employed with copolyamide-170 (PA-170) membrane material as packing to determine the retention volume (V'R) and equilibrium distribution coefficient (K'A) of both inorganic solutes and organic solutes. Based on the experimental data, the interfacial parameters of the packing material are obtained.

  6. SCREENING CORD BLOOD FOR HEMOGLOBINOPATHIES AND THALASSEMIA BY HPLC

    NARCIS (Netherlands)

    VANDERDIJS, FPL; VANDENBERG, GA; SCHERMER, JG; MUSKIET, FD; LANDMAN, H; MUSKIET, FAJ

    1992-01-01

    We evaluated the use of an HPLC method for screening hemoglobins in cord blood. We studied the genotype frequencies of the structural hemoglobin variants HbS and HbC and the synthesis variants alpha- and beta+-thalassemia in babies born on Curacao. During three months, 67.2% of all (748) newborns we

  7. Ultratraces of carotenes in tomato purees : HPLC-TLS study

    NARCIS (Netherlands)

    Luterotti, S.; Markovic, K.; Franko, M.; Bicanic, D.D.; Vahcic, N.; Doka, O.

    2003-01-01

    The present study was designed to provide information about (i) the profile of carotene pigments and (ii) trace quantities of lycopene and -carotene left in tomato purées. The ultrasensitive method comprising HPLC and thermal lens spectrometric (TLS) detection enabled us to detect as low as 0.3 and

  8. SCREENING CORD BLOOD FOR HEMOGLOBINOPATHIES AND THALASSEMIA BY HPLC

    NARCIS (Netherlands)

    VANDERDIJS, FPL; VANDENBERG, GA; SCHERMER, JG; MUSKIET, FD; LANDMAN, H; MUSKIET, FAJ

    We evaluated the use of an HPLC method for screening hemoglobins in cord blood. We studied the genotype frequencies of the structural hemoglobin variants HbS and HbC and the synthesis variants alpha- and beta+-thalassemia in babies born on Curacao. During three months, 67.2% of all (748) newborns

  9. Determination of selenomethionine, selenocysteine, and inorganic selenium in eggs by HPLC-inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lipiec, Elzbieta; Siara, Grzegorz [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Pau (France); Warsaw University of Technology, Warsaw (Poland); Bierla, Katarzyna; Ouerdane, Laurent; Szpunar, Joanna [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Pau (France)

    2010-05-15

    A method for the simultaneous determination of selenomethionine (SeMet), selenocysteine (SeCys), and selenite [Se(IV)] in chicken eggs was developed. A sample preparation protocol including defatting, protein denaturation, and carbamidomethylation was optimized in order to achieve complete protein digestion and to avoid SeCys losses. Quantification was carried out by reversed-phase HPLC-inductively coupled plasma mass spectrometry (ICP MS) after quantitative isolation of the selenium-containing fraction by size-exclusion liquid chromatography. The detection limits were 0.06, 0.003, and 0.01 {mu}g g{sup -1} (dry weight) for SeCys, Se(IV) and SeMet, respectively, and the precision was 5-10%. The end products of carbamidomethylation of the different selenium species were identified for the first time by electrospray QTOF MS after custom-designed 2D HPLC purification. Differences in selenium speciation in egg yolk and white were highlighted, the yolk containing more SeCys and the white more SeMet. An insight into selenium bioaccessibility in eggs was obtained by digestion with simulated gastric and gastrointestinal juices and size-exclusion HPLC-ICP MS. (orig.)

  10. Application of 2D-HPLC/taste dilution analysis on taste compounds in aniseed (Pimpinella anisum L.).

    Science.gov (United States)

    Pickrahn, Stephen; Sebald, Karin; Hofmann, Thomas

    2014-09-24

    This is the first application of fully automated, preparative, two-dimensional HPLC combined with sensory analysis for taste compound discovery using a sweet and licorice-like bitter-tasting aniseed extract as an example. Compared to the traditional iterative fractionation of food extracts by sensory-guided sequential application of separation techniques, the fully automated 2D-HPLC allowed the comprehensive separation of the aniseed extract into 256 subfractions and reduced the fractionation time from about 1 week to <1day. Using a smart sensory strategy to locate high-impact fractions, e.g., by evaluating first-dimension fractions by reconstituting them from second-dimension subfractions, followed by straightforward application of the taste dilution analysis on the individual second-dimension subfractions revealed the sweet-tasting trans-anethole and the bitter-tasting trans-pseudoisoeugenol 2-methylbutyrate, showing recognition thresholds of 70 and 68 μmol/L, respectively, as the primary orosensory active compounds in aniseed. 2D-HPLC combined with smart sensory analysis seems to be a promising strategy to speed the discovery of the key players imparting the attractive taste of foods.

  11. Speciation of mercury in water and fish samples by HPLC-ICP-MS after magnetic solid phase extraction.

    Science.gov (United States)

    Zhu, Siqi; Chen, Beibei; He, Man; Huang, Tong; Hu, Bin

    2017-08-15

    In this paper, Fe3O4@SiO2@γ-mercaptopropyltrimethoxysilane (γ-MPTS) magnetic nanoparticles was prepared and a new method of magnetic solid phase extraction (MSPE)-high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) was developed for the speciation of mercury including inorganic mercury (Hg(2+)), methylmercury (MeHg(+)) and phenylmercury (PhHg(+)) in environmental water, wastewater, tap water and fish samples. A rapid separation of three target mercury species was achieved in 8min by employing relatively high ratio of methanol in HPLC mobile phase. Various parameters affecting Fe3O4@SiO2@γ-MPTS-based MSPE of target mercury species have been investigated. Under the optimized conditions, the limits of detection for Hg(2+), MeHg(+) and PhHg(+) were in the range of 0.49-0.74ngL(-1). The intra- and inter-day relative standard deviations (n=5) were less than 9.0% and 12%, respectively. The developed MSPE-HPLC-ICP-MS method was validated by the speciation of mercury in the Certified Reference Material of DORM-2 dogfish as well as real-world samples including environmental water, wastewater, tap water and fish samples, and it has the advantages of simple operation, rapid separation, high sensitivity, high enrichment factor and is suitable for the analysis of mercury species in samples with complex matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Application of an Optimized HPLC Method for the Detection of Various Phenolic Compounds in Apples from Lithuanian Cultivars

    Directory of Open Access Journals (Sweden)

    Mindaugas Liaudanskas

    2014-01-01

    Full Text Available A specific analytical procedure including sample preparation and HPLC analysis was developed and validated for the detection of phenolic compounds in the samples of different apples from popular Lithuanian cultivars “Aldas,” “Auksis,” “Ligol,” and “Šampion.” The conditions for phenol extraction were optimized: the solvent of the extraction was 70% (v/v ethanol, and the extraction was performed in an ultrasound bath for 20 min at the temperature of 40°C. The HPLC mobile phase consisted of 2% (v/v acetic acid in water and 100% (v/v acetonitrile. Using the HPLC technique, 11 analytes were identified, and their specificity was confirmed: procyanidin B1, (+-catechin, chlorogenic acid, procyanidin B2, (−-epicatechin, rutin, hyperoside, isoquercitrin, avicularin, quercitrin, and phloridzin. Chlorogenic acid was the major component in “Aldas,” “Auksis,” and “Ligol” and procyanidin B2 in “Šampion.” Hyperoside and avicularin were the dominant compounds of all the identified quercetin derivatives in “Aldas” and “Auksis;” hyperoside in “Šampion;” and quercitrin in “Ligol.” The total content of phenolic compounds varied from 1641.0 ± 47.9 μg/g (cv. “Ligol” to 4291.3 ± 154.2 μg/g (cv. “Aldas”.

  13. Robust HPLC-MS/MS method for levofloxacin and ciprofloxacin determination in human prostate tissue.

    Science.gov (United States)

    Szerkus, O; Jacyna, J; Gibas, A; Sieczkowski, M; Siluk, D; Matuszewski, M; Kaliszan, R; Markuszewski, M J

    2017-01-05

    Fluoroquinolones are the drugs of choice in the prevention of bacterial infections after transrectal ultrasound guided prostate biopsy. In order to improve assessment of antibacterial efficacy in the target tissue a simple, selective, rapid and robust HPLC-ESI-MS/MS method for the determination of levofloxacin and ciprofloxacin concentrations in human prostate bioptates was developed and validated. Preparation procedure for prostate samples (10mg) was carried out using homogenization and filtration steps. Analyses were performed within 3.5min using RP C18 column in the isocratic elution mode with mobile phase composed of a mixture of 0.1% formic acid aqueous solution and 0.1% formic acid methanol solution (v/v; 79:21). The method was linear between 0.3μg/g and 15μg/g for levofloxacin and ciprofloxacin with coefficient of correlation (r) ≥0.999. The limit of detection and the limit of quantification for levofloxacin were 0.06μg/g and 0.2μg/g and for ciprofloxacin were 0.04μg/g and 0.13μg/g, respectively. Average concentrations (±SD) of levofloxacin and ciprofloxacin obtained from patients tissue were 5.4±2.2μg/g and 3.9±1.5μg/g, respectively. Additionally, during validation procedure a novel, experimental design approach was applied for the robustness study. For evaluation of analytical method robustness, Plackett-Burman design was employed and for sample preparation method robustness Fractional Factorial design was used. The developed and validated method was successfully applied to examine prostate tissue samples obtained from patients enrolled into a clinical study. Up to now, there has been no other HPLC-ESI-MS/MS method reported for the simultaneous determination of levofloxacin and ciprofloxacin in human prostatic tissue. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. HPLC method for the determination of oxytocin in pharmaceutical dosage form and comparison with biological method.

    Science.gov (United States)

    Dudkiewicz-Wilczyńska, J; Snycerski, A; Tautt, J

    2000-01-01

    Conditions have been established for the determination of oxytocin by the HPLC method; the method has been validated. The results of HPLC determinations are compared with those obtained by the biological method.

  15. Large Scale Solid Phase Synthesis of Peptide Drugs: Use of Commercial Anion Exchange Resin as Quenching Agent for Removal of Iodine during Disulphide Bond Formation

    Directory of Open Access Journals (Sweden)

    K. M. Bhaskara Reddy

    2012-01-01

    Full Text Available The S-acetamidomethyl (Acm or trityl (Trt protecting groups are widely used in the chemical synthesis of peptides that contain one or more disulfide bonds. Treatment of peptides containing S-Acm protecting group with iodine results in simultaneous removal of the sulfhydryl protecting group and disulfide formation. However, the excess iodine needs to be quenched or adsorbed as quickly as possible after completion of the disulfide bond formation in order to minimize side reactions that are often associated with the iodination step. We report here a simple method for simultaneous quenching and removal of iodine and isolation of disulphide bridge peptides. The use of excess inexpensive anion exchange resin to the oxidized peptide from the aqueous acetic acid/methanol solution affords quantitative removal of iodine and other color impurities. This improves the resin life time of expensive chromatography media that is used in preparative HPLC column during the purification of peptide using preparative HPLC. Further, it is very useful for the conversion of TFA salt to acetate in situ. It was successfully applied commercially, to the large scale synthesis of various peptides including Desmopressin, Oxytocin, and Octreotide. This new approach offers significant advantages such as more simple utility, minimal side reactions, large scale synthesis of peptide drugs, and greater cost effectiveness.

  16. Authentication of Cassia seeds on the basis of two-wavelength HPLC fingerprinting with the use of chemometrics

    Institute of Scientific and Technical Information of China (English)

    Serge; Kokot

    2010-01-01

    High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets were combined into one matrix.The application of principal component analysis(PCA) for this data matrix showed that the samples were clustered into four groups in accordance with the plant sources and preparation procedures.Furthermore,partial least squares(PLS),back propagation artificial neu...

  17. Preparative separation of grape skin polyphenols by high-speed counter-current chromatography.

    Science.gov (United States)

    Luo, Lanxin; Cui, Yan; Zhang, Shuting; Li, Lingxi; Li, Yuanyuan; Zhou, Peiyu; Sun, Baoshan

    2016-12-01

    To develop an efficient method for large preparation of various individual polyphenols from white grape skins (Fernão Pires; Vitis vinifera) by preparative high-speed counter-current chromatography (HSCCC) and preparative-HPLC, an optimized preparative HSCCC condition with two-phase solvent system composed of Hex-EtOAc-H2O (1:50:50, v/v) was used to separate grape skin polyphenols into various fractions. Both the tail-head and head-tail elution modes were used with a flow rate of 3.0ml/min and a rotary speed of 950rpm. Afterwards, a preparative-HPLC separation was applied to isolate individual polyphenols in each of the fractions from HSCCC. Total of 7 fractions (Fraction A to G) were obtained from grape skin extract by HSCCC. After preparative-HPLC isolation, fifteen individual compounds were obtained, most of which presented high yields and purity (all over 90%). The HSCCC method followed with preparative-HPLC appeared to be convenient and economical, constituting an efficient strategy for the isolation of grape skin polyphenols.

  18. Qualitative and quantitative determination of yohimbine in authentic yohimbe bark and in commercial aphrodisiacs by HPLC-UV-API/ MS methods.

    Science.gov (United States)

    Zanolari, Boris; Ndjoko, Karine; Ioset, Jean-Robert; Marston, Andrew; Hostettmann, Kurt

    2003-01-01

    The development and validation of a rapid qualitative and quantitative method based on an HPLC-UV-MS technique with atmospheric pressure chemical ionisation and electrospray ionisation for the analysis of yohimbine in a number of commercial aphrodisiac products is reported. HPLC with multiple-stage mass spectrometry experiments allowed the identification of the target compound and increased the selectivity of complex analyses such as those involved with multi-botanical preparations. The precision and the robustness of the method were improved by the use of two internal standards: codeine for UV detection and deuterium-labelled yohimbine for MS detection. Twenty commercial aphrodisiac preparations were analysed and the amount of yohimbine measured and expressed as the maximal dose per day suggested on product labels ranged from 1.32 to 23.16 mg.

  19. Quantification of the Triazole Antifungal Compounds Voriconazole and Posaconazole in Human Serum or Plasma Using Liquid Chromatography Electrospray Tandem Mass Spectrometry (HPLC-ESI-MS/MS).

    Science.gov (United States)

    Molinelli, Alejandro R; Rose, Charles H

    2016-01-01

    Voriconazole and posaconazole are triazole antifungal compounds used in the treatment of fungal infections. Therapeutic drug monitoring of both compounds is recommended in order to guide drug dosing to achieve optimal blood concentrations. In this chapter we describe an HPLC-ESI-MS/MS method for the quantification of both compounds in human plasma or serum following a simple specimen preparation procedure. Specimen preparation consists of protein precipitation using methanol and acetonitrile followed by a cleanup step that involves filtration through a cellulose acetate membrane. The specimen is then injected into an HPLC-ESI-MS/MS equipped with a C18 column and separated over an acetonitrile gradient. Quantification of the drugs in the specimen is achieved by comparing the response of the unknown specimen to that of the calibrators in the standard curve using multiple reaction monitoring.

  20. Dual High-Resolution α-Glucosidase and Radical Scavenging Profiling Combined with HPLC-HRMS-SPE-NMR for Identification of Minor and Major Constituents Directly from the Crude Extract of Pueraria lobata

    DEFF Research Database (Denmark)

    Liu, Bingrui; Kongstad, Kenneth Thermann; Qinglei, Sun

    2015-01-01

    The crude methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the crude extract without preceding purification was facilitated by combining chromatograms...... from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates. This allowed full bioactivity profiling of individual peaks in the HPLC...... chromatogram of the crude methanol extract. Subsequent HPLC-HRMS-SPE-NMR analysis allowed identification of 21 known compounds in addition to two new compounds, i.e., 3′-methoxydaidzein 8-C-[α-d-apiofuranosyl-(1→6)]-β-d-glucopyranoside and 6″-O-malonyl-3′-methoxydaidzin, as well as an unstable compound...

  1. Solution preparation

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, M.G.

    1982-01-01

    Reviewed in this statement are methods of preparing solutions to be used in laboratory experiments to examine technical issues related to the safe disposal of nuclear waste from power generation. Each approach currently used to prepare solutions has advantages and any one approach may be preferred over the others in particular situations, depending upon the goals of the experimental program. These advantages are highlighted herein for three approaches to solution preparation that are currently used most in studies of nuclear waste disposal. Discussion of the disadvantages of each approach is presented to help a user select a preparation method for his particular studies. Also presented in this statement are general observations regarding solution preparation. These observations are used as examples of the types of concerns that need to be addressed regarding solution preparation. As shown by these examples, prior to experimentation or chemical analyses, laboratory techniques based on scientific knowledge of solutions can be applied to solutions, often resulting in great improvement in the usefulness of results.

  2. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS

    Science.gov (United States)

    Tasioula-Margari, Maria; Tsabolatidou, Eleftheria

    2015-01-01

    The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected. PMID:26783843

  3. Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

    Science.gov (United States)

    Analytical methods for selenium (Se) speciation were developed using high performance liquid chromatography (HPLC) coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionization tandem mass spectrometry (ESI-MS/MS). Separations of selenomethionine (Se-Met) and sel...

  4. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS

    Directory of Open Access Journals (Sweden)

    Maria Tasioula-Margari

    2015-08-01

    Full Text Available The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO, from different Greek olive varieties. Sufficient recoveries (90% of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected.

  5. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS.

    Science.gov (United States)

    Tasioula-Margari, Maria; Tsabolatidou, Eleftheria

    2015-08-13

    The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected.

  6. Combination of TREF, high-temperature HPLC, FTIR and HPer DSC for the comprehensive analysis of complex polypropylene copolymers.

    Science.gov (United States)

    Cheruthazhekatt, Sadiqali; Pijpers, Thijs F J; Mathot, Vincent B F; Pasch, Harald

    2013-11-01

    A novel, powerful analytical technique, preparative temperature rising elution fractionation (prep TREF)/high-temperature (HT)-HPLC/Fourier transform infrared spectroscopy (FTIR)/high-performance differential scanning calorimetry (HPer DSC)), has been introduced to study the correlation between the polymer chain microstructure and the thermal behaviour of various components in a complex impact polypropylene copolymer (IPC). For the comprehensive analysis of this complex material, in a first step, prep TREF is used to produce less complex but still heterogeneous fractions. These chemically heterogeneous fractions are completely separated by using a highly selective chromatographic separation method--high-temperature solvent gradient HPLC. The detailed structural and thermal analysis of the HPLC fractions was conducted by offline coupling of HT-HPLC with FTIR spectroscopy and a novel DSC method--HPer DSC. Three chemically different components were identified in the mid-elution temperature TREF fractions. For the first component, identified as isotactic polypropylene homopolymer by FTIR, the macromolecular chain length is found to be an important factor affecting the melting and crystallisation behaviour. The second component relates to ethylene-propylene copolymer molecules with varying ethylene monomer distributions and propylene tacticity distributions. For the polyethylene component (last eluting component in all semi-crystalline TREF fractions), it was found that branching produced defects in the long crystallisable ethylene sequences that affected the thermal properties. The different species exhibit distinctively different melting and crystallisation behaviour, as documented by HPer DSC. Using this novel approach of hyphenated techniques, the chain structure and melting and crystallisation behaviour of different components in a complex copolymer were investigated systematically.

  7. Preparation and characterization of edible gelatin films from tilapia (Tilapia zillii)scales%罗非鱼鱼鳞明胶蛋白膜的制备及特性

    Institute of Scientific and Technical Information of China (English)

    吴菲菲; 翁武银; 苏文金; 曹敏杰; 刘光明

    2013-01-01

    利用罗非鱼鱼鳞提取明胶制备蛋白可食膜,考察了明胶蛋白的浸提温度、浸提时间以及甘油添加量对蛋白膜抗拉伸强度(TS)、断裂延伸率(EAB)等理化性质的影响.结果发现明胶蛋白提取率随浸提温度的升高和浸提时间的延长逐渐增大.利用80℃加热0.5、1h浸提时,明胶蛋白不易被降解,以其为原料制备的蛋白膜TS可高达44MPa.另一方面,当蛋白膜中的甘油含量从20%增加到40%时,膜的TS从44.09MPa下降至16.45 MPa,而EAB、水蒸汽透过率(WVP)和透明度值则逐渐升高.然而膜的颜色不受甘油添加量的影响.SDS-PAGE结果显示甘油对明胶膜的蛋白组分没有明显的影响.根据DSC的分析结果可知,甘油含量为20%时,明胶蛋白膜的玻璃化转变温度(Tg)高达113.97℃,但随着甘油含量的增加,膜的Tg逐渐降低.%Edible films based on the gelatin from tilapia scales were prepared.The effects of temperature and time of gelatin extraction,along with glycerol concentration on the film properties such as tensile strength (TS)and elongation at break(EAB) were also investigated.The extraction yield of scale gelatin was increased with increasing extraction temperature and time.TS of films prepared from the scale gelatin which was hardly degraded when extracting at 80℃ for 0.5h or 1 h,could reach a higher value at around 44MPa.When glycerol concentration in gelatin films was increased from 20% to 50%,TS of films was decreased from 44.09MPa to 16.45MPa,while EAB,water vapor permeability and transparency value was increased.However,the color of gelatin films was not markedly influenced by glycerol.SDS-PAGE patterns of gelatin films containing glycerol of different concentration showed no differences in the protein bands.Based on the DSC analysis,the glass transition temperature(Tg)of scale gelatin films with glycerol concentration of 20% could reach to 113.97℃,but decreased significantly with the glycerol

  8. Photodegradation of sparfloxacin and isolation of its degradation products by preparative HPLC

    National Research Council Canada - National Science Library

    E. E.S. Schapoval; A. L. Braga; P. R.H. Moreno; H. R.N. Salgado

    2009-01-01

    Sparfloxacin, a third generation fluoroquinolone derivative, is a potent antibacterial agent active against a wide range of Gram-positive and Gram-negative organisms including Streptococcus pneumoniae...

  9. Photodegradation of sparfloxacin and isolation of its degradation products by preparative HPLC

    Directory of Open Access Journals (Sweden)

    H. R.N. SALGADO

    2009-01-01

    Full Text Available

    Sparfloxacin, a third generation fluoroquinolone derivative, is a potent antibacterial agent active against a wide range of Gram-positive and Gram-negative organisms including Streptococcus pneumoniae, Staphylococcus aureus, methicillin resistant S. aureus, Legionella spp., Mycoplasma spp., Chlamydia spp. and Mycobacterium spp. A drawback of fluoroquinolones is their photoreactivity. Sparfloxacin has been studied in terms of therapeutic activities. However, there are few published of analytical methods being applied to sparfloxacin. The aim in this study was to determine the photodegradation products of sparfloxacin, when submitted to UV light, and to characterize two of these products, designated SPAX-PDP1 and SPAX-PDP2. An accelerated study of stability in methanol solution was carried out by exposing a solution of sparfloxacin to UV light (peak wavelength 290 nm for 36 hours at room temperature. The products were analyzed by NMR spectrophotometry, IR spectrometry and mass spectrophotometry. The results suggest that the products isolated here could be used to estimate the degradation of sparfloxacin in a stability study. However, the low activity exhibited by UV-irradiated sparfloxacin is a source of concern that demands further investigation of the mechanism of its photodegradation mechanism. Keywords: Degradation products, fluoroquinolone, photodegradation, quality control, sparfloxacin, stability.

  10. Simultaneous RP HPLC Determination of Aceclofenac, Paracetamol and Tizanidine in Pharmaceutical Preparations

    Directory of Open Access Journals (Sweden)

    V. V. Vaidya

    2010-01-01

    Full Text Available A simple, fast and precise reverse phase high performance liquid chromatographic method is developed for the simultaneous determination of aceclofenac, paracetamol and tizanidine. Chromatographic separation of the three drugs were performed on a hypersil C18 column (250 mm x 4.6 mm, 5 µm as stationary phase with a mobile phase comprising of mix phosphate buffer pH 7.0: acetonitrile (40:60 v/v, at a flow rate of 0.7 mL min-1 and UV detection at 230 nm. The proposed method was validated for linearity, accuracy, precision, LOD, LOQ. Linearity, accuracy and precision were found to be acceptable over the ranges of 100-300 µg mL-1 for aceclofenac, 500-1500 µg mL-1 for paracetamol and 2-6 µg mL-1 for tizanidine HCl equivalent to tizanidine. It can be conveniently adopted for routine quality control analysis.

  11. Vergelijking van HPLC-methoden voor de bepaling van pentachloorfenol in houtmonsters

    NARCIS (Netherlands)

    Goewie; C.E.; Berkhoff; C.J.

    1986-01-01

    Een vergelijkend onderzoek is verricht naar de bruikbaarheid van verschillende detectiemethoden in combinatie met HPLC voor de analyse van pentachloorfenol in hout. In het onderzoek wordt RP-HPLC met UK en amperometrische detectie beschreven, evenals NP-HPLC met elektroneninvangdetectie. In vers

  12. Vergelijking van HPLC-methoden voor de bepaling van pentachloorfenol in houtmonsters

    NARCIS (Netherlands)

    Goewie; C.E.; Berkhoff; C.J.

    1986-01-01

    Een vergelijkend onderzoek is verricht naar de bruikbaarheid van verschillende detectiemethoden in combinatie met HPLC voor de analyse van pentachloorfenol in hout. In het onderzoek wordt RP-HPLC met UK en amperometrische detectie beschreven, evenals NP-HPLC met elektroneninvangdetectie. In

  13. Preparation of Liberal Arts College Students' Learning Difficulties Self-rating Scale of Science Sources%理科来源的文科大学生学习困难自评量表的编制

    Institute of Scientific and Technical Information of China (English)

    江慧; 张见有; 阳泽

    2014-01-01

    Through literature analysis and open questionnaire, constructed science learning difficulties derived theoretical dimen-sion of the liberal arts college, and accordingly prepared the"liberal arts college science learning difficulties sources of self-rating scale."Exploratory factor analysis and confirmatory factor by 286 liberal arts college science sources to analyze the survey data, found that:liberal arts college science learning difficulties sources checklist includes the ability to acquire knowledge, arts achie-vement motivation and adaptability of this liberal arts three dimensions. The scale has clear factor structure and good reliability and validity. It can be taken as measuring tool of liberal art college students' learning difficulties of science sources.%通过文献分析和开放式问卷调查,构建了理科来源的文科大学生学习困难的理论维度,并据此编制了“理科来源的文科大学生学习困难自评量表”。通过对286名理科来源的文科大学生的调查数据进行探索性因素分析和验证性因素分析,发现:理科来源的文科大学生学习困难自评量表主要包括知识获得能力、文科成就动机和文科适应性这三个维度。量表的因素结构清晰,信效度良好。可以作为理科来源的文科大学生学习困难的测量工具。

  14. Bioequivalence and Pharmacokinetic Study of Glipizide by HPLC-MS/MS%HPLC-MS/MS测定格列吡嗪健康人体药动学及生物等效性

    Institute of Scientific and Technical Information of China (English)

    吴行伟; 刘霏霏; 曲恒燕; 郝光涛; 董瑞华; 高洪志; 梁宇光; 刘泽源

    2013-01-01

    OBJECTIVE To establish a simple and sensitive method of high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of glipizide in human plasma and to calculate the pharmacokinetic parameters and evaluate the bioequivalence of two glipizide preparations in healthy Chinese volunteers.METHODS A two-periods,randomized,crossover trial design was used.Twenty-four subjects took the test and reference preparations at the dose of 5 mg,and glipizide plasma concentration was determined by HPLC-MS/MS.Pharmacokinetic parameters were calculated and bioequivalence was evaluated.RESULTS The mean pharmacokinetic parameters of glipizide after adminstration of 5 mg of test or reference preparations were as follows:Pmax were (251.25 ±61.94) and (240.13 ±52.43) μg · L-1,t1/2were (4.85 ± 1.39) and (5.08 ± 1.76) h,tmax were (3.35 ± 1.22) and (3.38 ±1.35) h,and AUC0-tn were (1 561.44 ±475.73) and (1 588.82 ±507.40) μg · h · L-1,respectively.CONCLUSION The HPLC-MS/MS method is sensitive and simple,and can be used for the determination of glipizide plasma concentration.Statistical analysis of the pharmacokinetic parameters in heathy subjects indicated that the two preparations of glipizide are bioequivalent.%目的 建立一种简便、灵敏的测定人血浆中格列吡嗪血药浓度的高效液相色谱-串联质谱(HPLC-MS/MS)方法,计算两种制剂在中国健康受试者的药动学参数并评价生物等效性.方法 采用双周期、随机、自身交叉试验设计,24名受试者分别服用受试制剂或参比制剂5 mg,采用高效液相色谱-串联质谱法(HPLC-MS/ MS)测定其血药浓度.计算受试制剂和参比制剂的药动学参数并评价其生物等效性.结果 受试者口服受试制剂和参比制剂5 mg后格列吡嗪的平均Pmax分别为(251.25±61.94)和(240.13±52.43) μg·L-1,t1/2分别为(4.85±1.39)和(5.08±1.76)h,tmax分别为(3.35±1.22)和(3.38±1.35)h,AUC0-tn分别为(1 561.44±475.73)

  15. HPLC Fingerprints of Water Extract from Citrus aurantium L%枳壳药材水提液 HPLC 指纹图谱研究

    Institute of Scientific and Technical Information of China (English)

    陈刚; 魏鸿雁; 刘江华; 石明辉; 徐晓琴

    2014-01-01

    Objective To establish HPLC fingerprints of water extract fromCitrus aurantium L.Methods The sample solution was prepared by refluence and HPLC was employed to separate ingredients in Citrus aurantium L by gradient elution with mixture of acetonitrile and 0.1% formic acid and detected at 254 nm. The fingerprint data were analyzed by similarity evaluation.Results 12 common peaks were defined in dif-ferent fingerprints and 3 characteristic peaks were identified as naringin,isonaringin,and neohesperidin. The relative standard deviation (RSD)values of the relative retention time of 12 common peaks were lower than 0.805% when peak 5 (neohesperidin)was taken as reference peak.It was indicated that the present method was stable and reproducible.But,the RSD values of the relative peak area varied with fluctuation (-196.7%),which indicated that the content of active compounds in C.aurantium changed largely.Con-clusion This is the first HPLC fingerprint investigation on water - solubility ingredients for Citrus aurantium L and it could supply an effective guide for clinical drug use and collecting periods of Citrus aurantium L with water as extracting solvent.%目的:建立枳壳水提液中黄酮类成分特征指纹图谱方法。方法采用回流方法制备枳壳供试品溶液,以乙腈-0.1%甲酸水溶液梯度洗脱,检测波长254 nm,建立枳壳水提液的 HPLC 指纹图谱,对在江西省不同时间采收的枳壳药材进行相似度评价分析。结果从15批不同供试品指纹图谱中确定了12个共有峰,通过与对照品比对,指认了其中的3个特征峰,分别为柚皮苷、新橙皮苷、异柚皮苷。以新橙皮苷峰为参照峰,15批样品指纹图谱中12个共有峰的相对保留时间的相对标准偏差(RSD)均<0.805%。12个共有峰的相对峰面积变化较大, RSD 值为196.7%。结论该方法具有较好的重现性和稳定性,不同样品中化学成分的含量变化较大,可对

  16. HPLC-NMR在化学品检测中的应用前景%APPLICATION PROSPECTS OF HPLC-NMR IN CHEMICAL DETECTIONS

    Institute of Scientific and Technical Information of China (English)

    潘瑞花; 陈建华; 张剑锋

    2007-01-01

    简要介绍高效液相色谱-核磁共振(HPLC-NMR)联用技术.综述了目前HPLC-NMR联用技术在药物代谢研究,天然产物分析以及食品分析等方面的应用.展望了HPLC-NMR在化学品分类鉴定中的应用前景.

  17. New SI-traceable reference gas mixtures for sulfur hexafluoride (SF6) at the pmol/mol level using static and dynamic preparation methods and comparison to existing scales

    Science.gov (United States)

    Wyss, Simon A.; Guillevic, Myriam; Vicar, Martin; Nieuwenkamp, Gerard; Vollmer, Martin K.; Pascale, Céline; Reimann, Stefan; Niederhauser, Bernhard; Emmenegger, Lukas

    2017-04-01

    We developed two SI-traceable methods, using both static and dynamic preparation steps, to produce reference gas mixtures for sulfur hexafluoride (SF6) in gas cylinders at pmol/mol level. This research activity is conducted under the framework of the European EMRP HIGHGAS project, in support of the high quality measurements of this important greenhouse gas in the earth's atmosphere. In the method used by the Czech Metrology Institute (CMI) a parent mixture of SF6 in synthetic air was produced in an aluminium cylinder at VSL as a first step. This mixture was produced gravimetrically according to ISO 6142 at an amount fraction of 1 μmol/mol. In the second step this primary standard was further diluted to near-ambient amount fraction, with the use of a three-step dilution system and directly pressurised into aluminium cylinders to a pressure of 10 bars. The second method used by the Federal Institute of Metrology (METAS) has already been applied to other fluorinated gases such as HFC-125 and HFC-1234yf. In this method a highly concentrated mixture is produced by spiking a purified synthetic air (matrix gas) with SF6 from a permeation device. The mass loss of SF6 in the permeation device is observed by a magnetic suspension balance. In a second step this mixture is diluted with matrix gas to the desired concentrations. All flows are controlled with mass flow controllers. The diluted gas was transferred into Silconert2000-coated stainless steel cylinders by cryo-filling. The final gas mixtures at near-ambient amount fraction were measured on a Medusa gas chromatography-mass spectrometry system (Medusa-GC/MS) against working standards calibrated on existing scales of the Scripps Institution of Oceanography (SIO) and compared to other scales [1]. The agreement of the assigned values by the CMI and METAS, with the measured values referenced on the SIO scale was excellent. This results show that with this methods we are able to produce accurate SI-traceable gas mixtures at

  18. Stability of cefuroxime in 1% and 5% buffered eye drops determined with HPLC method.

    Science.gov (United States)

    Kodym, Anna; Wiśniewski, Andrzej; Knioła, Dawid; Olejniczak, Monika

    2011-01-01

    The aim of the studies was to develop formulary technologies of 1% and 5% eye drops containing cefuroxime with stability of at least 10-12 days. The stability was defined as the time required to reach the cutoff value of 10% degradation of cefuroxime in the drops, as determined using an HPLC assay. The drops should have such properties as optical clarity, pH in the range of 3.5 to 8.5 and osmotic pressure not lower than 280 mOsm/L. Additionally, drops of enhanced viscosity within the range 7-9 mPaxs were developed. Drops (1% and 5%) were prepared under aseptic conditions by dissolving Biofuroksym (Cefuroxime natricum) IBA Bioton--the form of the drug for dry injections--in citrate buffer of pH 6.05-6.28. Polyvinyl alcohol was used to increase the viscosity of the drops. Phenylmercuric borate at the final concentration of 0.001% was used together with beta-phenylethyl alcohol at the final concentration of 0.4% to preserve the drops. The drops were stored for 30 days in tightly closed glass bottles at the temperature of 4 degrees C and 20 degrees C, protected from light. As the course of the infection may differ in intensity, location and the area of the infection in the eye, the composition of the drops was developed at two concentrations (1% and 5%), and five formulary versions for each concentration were prepared. The concentration of cefuroxime in the drops was determined every three days using HPLC. Such properties as pH, osmotic pressure and viscosity were also examined. Additionally, organoleptic analysis (clarity, color, odor) was performed. Physical and chemical properties of all formulations of 1% and 5% drops containing cefuroxime prepared in citrate buffer of pH 6.05-6.28 met the standards set in the objective of the work. The stability of cefuroxime in buffered drops stored at the temperature of 4 degrees C, determined with HPLC as the time of 10% degradation of cefuroxime, was 15 days for 1% and 5% drops. In the drops, which were buffered and of

  19. Preparation of the pyridinium salts differing in the length of the N-alkyl substituent.

    Science.gov (United States)

    Marek, Jan; Stodulka, Petr; Cabal, Jiri; Soukup, Ondrej; Pohanka, Miroslav; Korabecny, Jan; Musilek, Kamil; Kuca, Kamil

    2010-03-19

    Quaternary pyridinium salts with chains ranging from C8 to C20 belong in the large group of cationic surfactants. In this paper, the preparation of such cationic surface active agents based on the pyridinium moiety and differing in the length of the N-alkyl chain is described. Additionally, HPLC technique was established to distinguish each prepared pyridinium analogue. This study represents universal method for preparation and identification of quaternary pyridinium detergents.

  20. Preparation of the Pyridinium Salts Differing in the Length of the N-Alkyl Substituent

    Directory of Open Access Journals (Sweden)

    Kamil Musilek

    2010-03-01

    Full Text Available Quaternary pyridinium salts with chains ranging from C8 to C20 belong in the large group of cationic surfactants. In this paper, the preparation of such cationic surface active agents based on the pyridinium moiety and differing in the length of the N-alkyl chain is described. Additionally, HPLC technique was established to distinguish each prepared pyridinium analogue. This study represents universal method for preparation and identification of quaternary pyridinium detergents.

  1. Preparation of HA/P(AM-SAS) blend and their inhibition performance of scale and corrosion%改性腐植酸新型阻垢缓蚀剂的制备及应用

    Institute of Scientific and Technical Information of China (English)

    邱广明; 邱广亮

    2001-01-01

    The blends [HA/P(AM-SAS)]of humic acids(HA)and copolymer P(AM-SAS) of acrylamide(AM) and sodium allylsulfonate(SAS) have been prepared by solution blend. Their inhibition performance of scale and corrosion and dispersion performance have been studied and compared with HA and P(AM-SAS). Experimental results indicates that their scale and corrosion inhibition rates and dispersing Fe2O3 capability increase with the increasing of their concentration. Compared with HA and P(AM-SAS),HA/P(AM-SAS)blends have better scale and corrosion inhibition performance and dispersion capability. During the blending of HA and P(AM-SAS),HA and P(AM-SAS)have synergistic effects for CaCO3 and Ca3(PO4)2 scale inhibition when HA/P(AM-SAS)mass ratio is above 1 and 2.Under the condition:ρ(Ca2+)=250 mg/L、ρ(HCO3-)=250 mg/L、ρ(CO32-)=85 mg/L、ρ(PO43-)=5 mg/L、pH=8.5、T=80 ℃、t=10 h,the inhibition rates of HA/P(AM-SAS)blends on the CaCO3 and Ca3(PO4)2 scale are up to 98.9%and 97.2%respectively. When the dosage ofHA/P(AM-SAS)blends is beyond 20 mg/L,the corrosion inhibition rate on mild steel reaches 95.0%.%采用溶液共混技术,制备了腐植酸钠(HA)和丙烯酰胺—烯丙基磺酸钠(SAS)共聚物[P(AM-SAS)]的共混物[HA/P(AM-SAS)],研究了共混物[HA/P(AM-SAS)]的阻垢、缓蚀和分散性能,并与HA和P(AM-SAS)做了对比分析。实验表明,HA/P(AM-SAS)共混物、HA和P(AM-SAS)的阻垢、缓蚀和分散能力随着使用浓度的增加而提高。与HA和P(AM-SAS)相比,HA/P(AM-SAS)共混物具有更好的阻垢、缓蚀和分散能力。当HA/P(AM-SAS)质量比超过1或2时,HA和P(AM-SAS)的共混对于CaCO3和Ca3(PO4)2的阻垢作用表现出了明显的协同效应。当ρ(Ca2+)=250 mg/L、ρ(HCO3-)=250 mg/L、ρ(CO32-)=85 mg/L、ρ(PO43-)=5 mg/L、pH=8.5、T=80 ℃、t=10 h时,HA/P(AM-SAS)共混物对CaCO3和Ca3(PO4)2的阻垢率分别达到了98.9%和97.2%。当HA/P(AM-SAS)共混物的使用浓度超过20 mg/L,共混物

  2. [Determination of chelerythrine in Chelidonium majus by RP-HPLC].

    Science.gov (United States)

    Sun, Nan; Yu, Liming

    2009-11-01

    To develop an HPLC method for determination of the content of chelerythrine in Chelidonium majus. Chelerythrine was extracted from the fine powder of the crade with drug methanol and determined by HPLC. The mobile phase was acetonitrile-1% triethylamine (25:75) (adjusted pH to 3 using phosphoric acid) and the detection wavelength was set at 268 nm. The linear range of calibration curve was 0.051 6-0.516 0 microg (r = 1.000). The average recovery (n = 6) was 103.0% with RSD of 1.2%. Chelerythrine in the sample solution was stable in 8 h and the ruggedness was perfect among 3 different chromatographic columns. The method is accurate, sensitive and reliable.

  3. A Review on Method Development and Validation using HPLC

    Directory of Open Access Journals (Sweden)

    Rashmi Adhikari

    2016-09-01

    Full Text Available High performance liquid chromatography (HPLC is an analytical technique which is used to separate, detect and quantify various drugs and its related degradants. It is employed to separate manufactured drugs from drug related impurities, to detect and quantify synthesized drug and to reduce other impurities at the time of separation. A number of chromatographic parameters were evaluated in order to optimize the method. An appropriate mobile phase, column, column temperature, wavelength and gradient must be found that affords suitable compatibility and stability of drug as well as degradants and impurities. Validation of HPLC as per ICH guidelines covers all the performance characteristics of validation, likeaccuracy, precision, specificity, linearity, range, limit of detection, limit of quantification, robustness and system suitability testing.

  4. Gradient Scouting in Reversed-Phase HPLC Revisited

    Science.gov (United States)

    Alcazar, A.; Jurado, J. M.; Gonzalez, A. G.

    2011-01-01

    Gradient scouting is the best way to decide the most suitable elution mode in reversed-phase high-performance liquid chromatography (RP-HPLC). A simple rule for this decision involves the evaluation of the ratio [delta]t/t[subscript G] (where [delta]t is the difference in the retention time between the last and the first peak and t[subscript G] is…

  5. Analysis of Trichothecene Mycotoxins by Combined HPLC/MS.

    Science.gov (United States)

    1986-04-15

    trichothecenes are known and several of them are natural contaminants of cereal grains(l). Ingestion of the contaminated foodstuffs by humans or farm... humans or farm animals is known to cause a wide variety of toxicoses often leading to death(2). Trichothecenes have also recently been implicated as...NO 3MI- NO ACCESSION NO 62770A 62770A871 AA 048 11. TITLE (Include Security Classification) (U) Analysis of Trichothecene Mycotoxins by Combined HPLC

  6. Gradient Scouting in Reversed-Phase HPLC Revisited

    Science.gov (United States)

    Alcazar, A.; Jurado, J. M.; Gonzalez, A. G.

    2011-01-01

    Gradient scouting is the best way to decide the most suitable elution mode in reversed-phase high-performance liquid chromatography (RP-HPLC). A simple rule for this decision involves the evaluation of the ratio [delta]t/t[subscript G] (where [delta]t is the difference in the retention time between the last and the first peak and t[subscript G] is…

  7. Direct 13C NMR Detection in HPLC Hyphenation Mode

    DEFF Research Database (Denmark)

    Wubshet, Sileshi Gizachew; Johansen, Kenneth; Nyberg, Nils

    2012-01-01

    Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments......, and an acquisition time of 13 h resulted in spectra with adequate signal-to-noise ratios to detect all C-13 signals....

  8. Comparison of the phenolic composition of fruit juices by single step gradient HPLC analysis of multiple components versus multiple chromatographic runs optimised for individual families.

    Science.gov (United States)

    Bremner, P D; Blacklock, C J; Paganga, G; Mullen, W; Rice-Evans, C A; Crozier, A

    2000-06-01

    After minimal sample preparation, two different HPLC methodologies, one based on a single gradient reversed-phase HPLC step, the other on multiple HPLC runs each optimised for specific components, were used to investigate the composition of flavonoids and phenolic acids in apple and tomato juices. The principal components in apple juice were identified as chlorogenic acid, phloridzin, caffeic acid and p-coumaric acid. Tomato juice was found to contain chlorogenic acid, caffeic acid, p-coumaric acid, naringenin and rutin. The quantitative estimates of the levels of these compounds, obtained with the two HPLC procedures, were very similar, demonstrating that either method can be used to analyse accurately the phenolic components of apple and tomato juices. Chlorogenic acid in tomato juice was the only component not fully resolved in the single run study and the multiple run analysis prior to enzyme treatment. The single run system of analysis is recommended for the initial investigation of plant phenolics and the multiple run approach for analyses where chromatographic resolution requires improvement.

  9. Combination of HPLC chromatogram and hypoglycemic effect identifies isoflavones as the principal active fraction of Belamcanda chinensis leaf extract in diabetes treatment.

    Science.gov (United States)

    Chen, Yan; Wu, Chong-Ming; Dai, Rong-Ji; Li, Liang; Yu, Yu-Hong; Li, Yan; Meng, Wei-Wei; Zhang, Liang; Zhang, Yongqian; Deng, Yu-Lin

    2011-02-15

    In previous study, we demonstrated the hypoglycemic effect of aqueous extract of Belamcanda chinensis leaves in rats. Here, we separated the aqueous extract of B. chinensis leaves and investigated the spectrum-effect relationships between HPLC chromatograms and hypoglycemic activities of different isolates from B. chinensis leaf extract. Sequential solvent extraction with petroleum ether, chloroform, acetic ester and n-butanol provided several isolates showing similar hypoglycemic activities, making it difficult to discriminate the active fractions. Stepwise elution through HP20 macroporous resin by water, 40% and 95% ethanol provided isolates with distinct hypoglycemic activities, representing a simple, rapid and efficient preparative separation method. Combination of HPLC chromatogram and pharmacological effect targeted a hypoglycemic activity-related region in HPLC chromatogram. Each peak in this region was analyzed by UV spectrum scan. Most of them were flavonoids in which tectoridin and swertisin were known flavonoids with anti-diabetic activities. In together, this work provides a general model of combination of HPLC chromatography and pharmacological effect to study the spectrum-effect relationships of aqueous extract from B. chinensis leaves, which can be used to find principle components of B. chinensis on pharmacological activity.

  10. Difluoromethane preparation

    NARCIS (Netherlands)

    Wiersma, A.; Sandt, E.J.A.; Van Bekkum, H.; Makkee, M.; Moulijn, J.A.

    1996-01-01

    Abstract of NL 9401574 (A) The invention relates to a method for preparing difluoromethane, wherein dichlorodifluoromethane or monochlorodifluoromethane is brought into contact with hydrogen in the presence of palladium on activated carbon, wherein the loading of the palladium on the activated c

  11. HPLC determination of pirenzepine dihydrochloride in rabbit aqueous humor.

    Science.gov (United States)

    Tu, Jiasheng; Li, Pengmei; Yang, Xiaoyan; Pang, Hui

    2005-08-05

    Pirenzepine was considered as a pharmacologic agent of preventing form-deprivation myopia. To assess the ocular bioavailability of pirenzepine, a HPLC method for determination of pirenzepine in rabbit aqueous humor was developed. An HPLC system was used in the reverse phase mode for the determination of pirenzepine. A Luna RP18 5 microm 4.6 mm x 150 mm column was employed at 35 degrees C. The mobile phase was methanol/0.02 M KH2PO4/sodium 1-pentanesulfonate (350/650/1, v/v/m, pH was adjusted to 8.0 by dropping 1M NaOH). The flow rate was 1 ml/min. Pirenzepine was monitored at 280 nm. Sample treatment procedure consists of deproteinisation with methanol. Calibration curves fitted by plotting the peak area versus concentration were linear in the range 20-400 ng/ml. The limit of quantification (LOQ) of present method was 20 ng/ml. Within-day and inter-day coefficient of variation was lower than 10%. Analytical recoveries were determined as 92.4, 95.4 and 101.4% at concentrations of 40, 200 and 400 ng/ml. In conclusion, this HPLC method using a simple sample treatment procedure appears suitable for monitoring ocular concentration of pirenzepine.

  12. Resonance Rayleigh scattering for detection of proteins in HPLC.

    Science.gov (United States)

    Lu, Xin; Luo, Zhihui; Liu, Chengwei; Zhao, Shulin

    2008-09-01

    An HPLC-resonance Rayleigh scattering (RRS) (HPLC-RRS) detection system is described for separation and detection of proteins. This system is based on the modification of a commercial HPLC instrument involving the addition of a pump and a T-shaped interface, and a common fluorescence detector was used for detection. The detection principle is based on the change of RRS intensity of the ion-association complex formed from biebrich scarlet (BS) and protein. The RRS signal was detected at lambdaex=lambdaem=376 nm. The utility of the presented method was demonstrated by the separation and determination of four proteins involving cytochrome (Cyt-c), lysozyme (Lys), HSA, and gamma-globulin (gamma-Glo). An LOD of 0.2-1.0 microg/mL was reached and a linear range was found between peak area and concentration in the range of 0.20-3.0 microg/mL for Cyt-c, 0.25-2.5 microg/mL for Lys, 1.5-10 microg/mL for HSA, and 2.0-15 microg/mL for gamma-Glo, with linear regression coefficients all above 0.99. The method presented has been applied to determine HSA and gamma-Glo in human serum samples synchronously.

  13. High performance liquid chromatography (HPLC fingerprints and primary structure identification of corn peptides by HPLC-diode array detection and HPLC-electrospray ionization tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Chi Wang

    2016-01-01

    Full Text Available Corn peptides (CPs are reported to have many biological functions, such as facilitating alcohol metabolism, antioxidation, antitumor, antihypertension, and hepatoprotection. To develop a method for quality control, the high-performance liquid chromatography (HPLC system was applied. Twenty-eight common peaks were found in all the CPs of corn samples from Enshi, China, based on which, a fingerprinting chromatogram was established for use in quality control in future research. Subsequently, the major chemical constituents of these common peaks were identified respectively using the HPLC-diode-array detection electrospray ionization tandem mass spectrometry (DAD-ESI-MS/MS system, and 48 peptide fractions were determined ultimately. This was the first time for the majority of these peptides to be reported, and many of them contained amino acids of glutamine (Q, L and A, which might play an important role in the exhibition of the bioactivities of CPs. Many peptides had a similar primary structure to the peptides which had been proven to be bioactive such as facilitating alcohol metabolism, scavenging free radicals, and inhibiting lipid peroxidation. This systematical analysis of the primary structure of CPs facilitated subsequent studies on the relationship between the structures and functions, and could accelerate holistic research on CPs.

  14. Preparing Apigenin from Leaves of Adinandra nitida

    Directory of Open Access Journals (Sweden)

    Zhengxiang Ning

    2008-01-01

    Full Text Available Leaves of Adinandra nitida were used as raw material, and a new industrially significant method of preparing apigenin was established by hydrolyzing a water extract and recrystallizing it with ethanol in order to obtain a new source for the production of this flavone. A yield of about 2.5 % (dry mass was obtained with the purity of 93.05 %, determined by high performance liquid chromatography (HPLC. Moreover, the main flavonoids in leaves of Adinandra nitida and the product after acid hydrolysis were identified as camellianin A and apigenin, respectively, by ultraviolet-visible spectrometry (UV/VIS and electrospray ionization mass spectrometry (ESI-MS.

  15. "Fit-for-purpose" development of analytical and (semi)preparative enantioselective high performance liquid and supercritical fluid chromatography for the access to a novel σ1 receptor agonist.

    Science.gov (United States)

    Rossi, Daniela; Marra, Annamaria; Rui, Marta; Brambilla, Stefania; Juza, Markus; Collina, Simona

    2016-01-25

    A rapid and straightforward screening protocol of chiral stationary phases (CSPs) in HPLC and SFC resulted in three different methods "fit-for-purpose", i.e. analysis and scale-up to semi-preparative enantioselective chromatography. The efficient use of these three methods allowed expedited preparation of an important drug discovery target, (R/S)-1, a potent new sigma 1 (σ1) receptor agonist. The approach taken resulted in significant savings of both time and labor for the isolation of enantiomers compared to the development of a stereo-selective synthesis. The enantiomers of 1 have been isolated allowing studies of their chirooptical properties and an in-deep comparative examination of the pharmacological profile for the individual enantiomers.

  16. Antineoplastic drugs determination by HPLC-HRMS(n) to monitor occupational exposure.

    Science.gov (United States)

    Dal Bello, Federica; Santoro, Valentina; Scarpino, Valentina; Martano, Chiara; Aigotti, Riccardo; Chiappa, Alberta; Davoli, Enrico; Medana, Claudio

    2016-07-01

    The purpose of this study was to develop a simple, direct, multiresidue highly specific procedure to evaluate the possible surface contamination of selected antineoplastic drugs in several hospital environment sites by using wipe test sampling. 5-fluorouracil (5-FU), carboplatin (C-Pt), cyclophosphamide (CYC), cytarabine (CYT), doxorubicin (DOX), gemcitabine (GEM), ifosfamide (IFO), methotrexate (MET), and mitomycin C (MIT) belong to very different chemical classes but show good ionization properties under electrospray ionization (ESI) conditions (negative ion mode for 5-FU and positive ion mode in all other cases). HPLC (high performance liquid chromatography) coupled with HRMS (high resolution mass spectrometry) appears to be the best technique for direct analysis of these analytes, because neither derivatization nor complex extraction procedure for polar compounds in samples is requested prior the analysis. Sample preparation was limited to washing wipes with appropriate solvents. Chromatographic separation was achieved on C18 reversed phase columns. The HPLC-HRMS/MS method was validated in order to obtain robustness, sensitivity and selectivity. LLOQ (lower limit of quantitation) values provided a sensitivity good enough to evidence the presence of the drugs in a very low concentration range (<1 pg/cm(2) ). The method was applied for a study of real wipe tests coming from many areas from a hospital showing some positive samples. The low quantitation limits and the high specificity due to the high resolution approach of the developed method allowed an accurate description of the working environment that can be used to define procedural rules to limit working place contamination to a minimum. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  17. Stability of ceftazidime in 1% and 5% buffered eye drops determined with HPLC method.

    Science.gov (United States)

    Kodym, Anna; Hapka-Zmich, Dominika; Gołab, Marta; Gwizdala, Magdalena

    2011-01-01

    The aim of the studies was to determine with HPLC method the stability of ceftazidime in buffered 1% and 5% eye drops of proposed formulary composition, which were stored for 30 days at the temperature of 4 degrees C and 20 degrees C and protected from light. The 1% and 5% eye drops were prepared under aseptic conditions by dissolving Biotum (ceftazidimum), dry injection formulation, in citrate buffer of pH 6.10-6.24. The viscosity of the eye drops was increased with polyvinyl alcohol, phenylmercuric borate combined with 2-phenylethanol was used to preserve the eye drops. The eye drops were stored for 30 days in sterile glass bottles at the temperature of 4 degrees C and 20 degrees C and protected from light. The concentration of ceftazidime and pyridine was analyzed simultaneously with HPLC method every three days; pH, osmotic pressure and viscosity were examined as well as the organoleptic analysis of the eye drops (clarity, color, odor). Storage temperature had the biggest impact on ceftazidime stability in the eye drops. The stability of the drops depended also on ceftazidime concentration in the eye drops, the presence of preservatives and polyvinyl alcohol. The time of 10% ceftazidime degradation in buffered 1% and 5% eye drops, stored at the temperature of 4 degrees C, was from 27 to 18 days in 1% eye drops and from 21 to 12 days in 5% eye drops, depending on their composition. In the eye drops which were stored at the temperature of 20 degrees C 10% ceftazidime degradation occurred on the 3rd day of storage in all 1% and 5% formulary versions.

  18. An HPLC-UV method for determining plasma dimethylacetamide concentrations in patients receiving intravenous busulfan.

    Science.gov (United States)

    Cendana, Mildred; Lee, Samiuela; Upadhyay, Parth J; Byrne, Jennifer A; Shaw, Peter J; Earl, John; Nath, Christa E

    2016-12-07

    Dimethylacetamide (DMA) is a solvent used in the preparation of intravenous busulfan, an alkylating agent used in blood or marrow transplantation. DMA may contribute to hepatic toxicity, so it is important to monitor its clearance. The aim of this study was to develop an HPLC-UV assay for measurement of DMA in human plasma. After precipitation of plasma proteins with acetonitrile followed by dilution (1:4) with water, the extract was injected onto the HPLC and detected at 195 nm. Separation was performed using a Cogent-HPS 5 μm C18 column (250 × 4.6 mm) preceded by a Brownlee 7 μm RP18 , pre-column (1.5 cm × 3.2 mm). The mobile phase was 25 mm sodium phosphate buffer (pH 3), containing 2.5% (v/v) acetonitrile and 0.0005% (v/v) sodium-octyl-sulfonate. Using a flow rate of 1 mL/min, the retention times of DMA and the internal standard (IS), 2-chloroacetamide, were 9.5 and 3.5 min, respectively. Peak area ratio (DMA:IS) was a linear function of concentration from 1 to 1000 μg/mL. There was excellent intraday precision (<5% for 5-700 μg/mL DMA), accuracy (<3% deviation from the true concentration) and recovery (74-98%). The limits of detection and quantification were 1 and 5 μg/mL, respectively. In eight children who received intravenous busulfan, DMA concentrations ranged from 110 to 438 μg/mL.

  19. Qualitative and Quantitative Analysis of Lignan Constituents in Caulis Trachelospermi by HPLC-QTOF-MS and HPLC-UV

    Directory of Open Access Journals (Sweden)

    Xiao-Ting Liu

    2015-05-01

    Full Text Available A high-performance liquid chromatography coupled with quadrupole tandem time-of-flight mass (HPLC-QTOF-MS and ultraviolet spectrometry (HPLC-UV was established for simultaneous qualitative and quantitative analysis of the major chemical constituents in Caulis Trachelospermi, respectively. The analysis was performed on an Agilent Zorbax Eclipse Plus C18 column (4.6 mm × 150 mm, 5 μm using a binary gradient system of water and methanol, with ultraviolet absorption at 230 nm. Based on high-resolution ESI-MS/MS fragmentation behaviors of the reference standards, the characteristic cleavage patterns of lignano-9, 9'-lactones and lignano-8'-hydroxy-9, 9'-lactones were obtained. The results demonstrated that the characteristic fragmentation patterns are valuable for identifying and differentiating lignano-9,9'-lactones and lignano-8'-hydroxy-9,9'-lactones. As such, a total of 25 compounds in Caulis Trachelospermi were unambiguously or tentatively identified via comparisons with reference standards or literature. In addition, 14 dibenzylbutyrolatone lignans were simultaneously quantified in Caulis Trachelospermi by HPLC-UV method. The method is suitable for the qualitative and quantitative analyses of dibenzylbutyrolatone lignans in Caulis Trachelospermi.

  20. Qualitative and Quantitative Analysis of Lignan Constituents in Caulis Trachelospermi by HPLC-QTOF-MS and HPLC-UV.

    Science.gov (United States)

    Liu, Xiao-Ting; Wang, Xu-Guang; Yang, Yu; Xu, Rui; Meng, Fan-Hua; Yu, Neng-Jiang; Zhao, Yi-Min

    2015-05-05

    A high-performance liquid chromatography coupled with quadrupole tandem time-of-flight mass (HPLC-QTOF-MS) and ultraviolet spectrometry (HPLC-UV) was established for simultaneous qualitative and quantitative analysis of the major chemical constituents in Caulis Trachelospermi, respectively. The analysis was performed on an Agilent Zorbax Eclipse Plus C18 column (4.6 mm×150 mm, 5 μm) using a binary gradient system of water and methanol, with ultraviolet absorption at 230 nm. Based on high-resolution ESI-MS/MS fragmentation behaviors of the reference standards, the characteristic cleavage patterns of lignano-9, 9'-lactones and lignano-8'-hydroxy-9, 9'-lactones were obtained. The results demonstrated that the characteristic fragmentation patterns are valuable for identifying and differentiating lignano-9,9'-lactones and lignano-8'-hydroxy-9,9'-lactones. As such, a total of 25 compounds in Caulis Trachelospermi were unambiguously or tentatively identified via comparisons with reference standards or literature. In addition, 14 dibenzylbutyrolatone lignans were simultaneously quantified in Caulis Trachelospermi by HPLC-UV method. The method is suitable for the qualitative and quantitative analyses of dibenzylbutyrolatone lignans in Caulis Trachelospermi.

  1. Chemical Differentiation of Dendrobium officinale and Dendrobium devonianum by Using HPLC Fingerprints, HPLC-ESI-MS, and HPTLC Analyses.

    Science.gov (United States)

    Ye, Zi; Dai, Jia-Rong; Zhang, Cheng-Gang; Lu, Ye; Wu, Lei-Lei; Gong, Amy G W; Xu, Hong; Tsim, Karl W K; Wang, Zheng-Tao

    2017-01-01

    The stems of Dendrobium officinale Kimura et Migo (Dendrobii Officinalis Caulis) have a high medicinal value as a traditional Chinese medicine (TCM). Because of the limited supply, D. officinale is a high priced TCM, and therefore adulterants are commonly found in the herbal market. The dried stems of a closely related Dendrobium species, Dendrobium devonianum Paxt., are commonly used as the substitute; however, there is no effective method to distinguish the two Dendrobium species. Here, a high performance liquid chromatography (HPLC) method was successfully developed and applied to differentiate D. officinale and D. devonianum by comparing the chromatograms according to the characteristic peaks. A HPLC coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MS) method was further applied for structural elucidation of 15 flavonoids, 5 phenolic acids, and 1 lignan in D. officinale. Among these flavonoids, 4 flavonoid C-glycosides were firstly reported in D. officinale, and violanthin and isoviolanthin were identified to be specific for D. officinale compared with D. devonianum. Then, two representative components were used as chemical markers. A rapid and reliable high performance thin layer chromatography (HPTLC) method was applied in distinguishing D. officinale from D. devonianum. The results of this work have demonstrated that these developed analytical methods can be used to discriminate D. officinale and D. devonianum effectively and conveniently.

  2. Chemical Differentiation of Dendrobium officinale and Dendrobium devonianum by Using HPLC Fingerprints, HPLC-ESI-MS, and HPTLC Analyses

    Directory of Open Access Journals (Sweden)

    Zi Ye

    2017-01-01

    Full Text Available The stems of Dendrobium officinale Kimura et Migo (Dendrobii Officinalis Caulis have a high medicinal value as a traditional Chinese medicine (TCM. Because of the limited supply, D. officinale is a high priced TCM, and therefore adulterants are commonly found in the herbal market. The dried stems of a closely related Dendrobium species, Dendrobium devonianum Paxt., are commonly used as the substitute; however, there is no effective method to distinguish the two Dendrobium species. Here, a high performance liquid chromatography (HPLC method was successfully developed and applied to differentiate D. officinale and D. devonianum by comparing the chromatograms according to the characteristic peaks. A HPLC coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MS method was further applied for structural elucidation of 15 flavonoids, 5 phenolic acids, and 1 lignan in D. officinale. Among these flavonoids, 4 flavonoid C-glycosides were firstly reported in D. officinale, and violanthin and isoviolanthin were identified to be specific for D. officinale compared with D. devonianum. Then, two representative components were used as chemical markers. A rapid and reliable high performance thin layer chromatography (HPTLC method was applied in distinguishing D. officinale from D. devonianum. The results of this work have demonstrated that these developed analytical methods can be used to discriminate D. officinale and D. devonianum effectively and conveniently.

  3. HPLC FOR CONTROL STABILITY OF QUERCETIN INJECTABLE DOSAGE FORM

    Directory of Open Access Journals (Sweden)

    Martynov AV

    2016-12-01

    Full Text Available Introduction. Quercetin is a flavone derivatives which known like a substances with vitamin activity, high antioxidant, antimutagenic and anticarcinogenic activity and many other types of biological activity. Wide usage of quercetin prevents their polyphenolic nature structure which does not allow a high bioavailability of pure quercetin when administered orally. This is associated with a wide spectrum variety of chemical reactions for the phenolic groups: from interaction with amino acid residues in proteins to reactions with amine heterocyclic alkaloids and polysaccharides. In our days Corvitin – one from the number of quercetin based drugs with sufficiently low levels all types toxicity, allergenic and has no irritating action on intravenous administration. In the same time quercetin cannot be used in full measure because of the limited number of publications with analysis methods, especially HPLC. Determining the stability over time of concentrate quercetin solution, as well as determining the stability of the concentrate to the original autoclave sterilization conditions is a promising direction in creating new drugs. Materials and methods The objective was to research quercetin soluble formulation samples in different conditions: 1 fresh dilute concentrate (0.9% sodium chloride; 2 the original dilute concentrate, which was stored at room temperature for 14 days in light and 3 similar to the first sample dilute concentrate, which went before breeding in autoclaving at 120 0 C for 20 minutes. The objects used in the studies were industrial drug-substance quercetin (Sinkea manufactured (China, the original pharmaceutical composition as the soluble form of quercetin for injection and aerosol applications, glycerol (Sigma, Polysorbat 80 (Merk, ethanol 96 %. For the HPLC – analysis, chromatograph "Milichrom A-02" (SiChrom, Knauer (Econova, Novosibirsk, Russia was used. Results and discussion Quercetin was identified using information on its

  4. Quantification of appetite suppressing steroid glycosides from Hoodia gordonii in dried plant material, purified extracts and food products using HPLC-UV and HPLC-MS methods

    NARCIS (Netherlands)

    Janssen, H.-G.; Swindells, C.; Gunning, P.; Wang, W.; Grün, C.; Mahabir, K.; Maharaj, V.J.; Apps, P.J.

    2008-01-01

    High-performance liquid chromatography (HPLC)-UV and HPLC-Mass Spectrometry (MS) methods were developed for the quantitative analysis of the family of Hoodia gordonii steroid glycosides with appetite suppressing properties in dried plant material, in purified and enriched extracts and in various pro

  5. Rapid separation and identification of 54 major constituents in Buyang Huanwu decoction by ultra-fast HPLC system coupled with DAD-TOF/MS.

    Science.gov (United States)

    Liu, E-Hu; Qi, Lian-Wen; Peng, Yong-Bo; Cheng, Xiao-Lan; Wu, Qian; Li, Ping; Li, Chang-Yin

    2009-08-01

    Buyang Huanwu Decoction (BYHWD), is a well-known traditional Chinese preparation consisting of Radix Astragali, Radix Angelicae Sinensis, Rhizoma Ligustici Chuanxiong, Radix paeoniae Rubra, Flos Carthami, Semen Persicae and Lumbricus. An ultra-fast high-performance liquid chromatography (HPLC) method coupled with diode array detection (DAD) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) has been developed for rapid separation and structural identification of constituents in BYHWD. Using an ultra-fast HPLC system with short columns (4.6 x 50 mm, 1.8 microm), the total analysis time for this complex prescription is less than 30 min. With various fragmentor voltages in TOF/MS, accurate mass measurements (less than 5 ppm error) for molecular ions and characteristic fragment ions could represent reliable identification criteria for these compounds. Fifty-four major constituents from BYHWD sample, including four C-glycosyl quinochalcones, four flavonoid O-glycosides, sixteen isoflavones, six monoterpene glycosides, eight saponins, four organic acids and five amino acids, were identified or tentatively characterized based on their retention times, DAD and TOF/MS data. All the compounds were further assigned in the seven individual crude drugs. In conclusion, the ultra-fast HPLC with DAD-TOF/MS is a highly useful and efficient technique to separate and identify constituents in complex matrices of herbal medicines or preparations.

  6. Chemometrics-Assisted UV Spectrophotometric and RP-HPLC Methods for the Simultaneous Determination of Tolperisone Hydrochloride and Diclofenac Sodium in their Combined Pharmaceutical Formulation.

    Science.gov (United States)

    Gohel, Nikunj Rameshbhai; Patel, Bhavin Kiritbhai; Parmar, Vijaykumar Kunvarji

    2013-01-01

    Chemometrics-assisted UV spectrophotometric and RP-HPLC methods are presented for the simultaneous determination of tolperisone hydrochloride (TOL) and diclofenac sodium (DIC) from their combined pharmaceutical dosage form. Chemometric methods are based on principal component regression and partial least-square regression models. Two sets of standard mixtures, calibration sets, and validation sets were prepared. Both models were optimized to quantify each drug in the mixture using the information included in the UV absorption spectra of the appropriate solution in the range 241-290 nm with the intervals λ = 1 nm at 50 wavelengths. The optimized models were successfully applied to the simultaneous determination of these drugs in synthetic mixture and pharmaceutical formulation. In addition, an HPLC method was developed using a reversed-phase C18 column at ambient temperature with a mobile phase consisting of methanol:acetonitrile:water (60:30:10 v/v/v), pH-adjusted to 3.0, with UV detection at 275 nm. The methods were validated in terms of linearity, accuracy, precision, sensitivity, specificity, and robustness in the range of 3-30 μg/mL for TOL and 1-10 μg/mL for DIC. The robustness of the HPLC method was tested using an experimental design approach. The developed HPLC method, and the PCR and PLS models were used to determine the amount of TOL and DIC in tablets. The data obtained from the PCR and PLS models were not significantly different from those obtained from the HPLC method at 95% confidence limit.

  7. How Prepared is Prepared Enough?

    Science.gov (United States)

    Porter-Levy; Macleod; Rickert

    1996-10-01

    A 17-year-old female was in the final stage in treatment of right unilateral cleft lip and palate. She had undergone a number of previous surgeries. Hearing and speech were good on evaluation, and her social and family situation were deemed excellent. After preparatory orthodontics she underwent a Lefort I maxillary advancement. Surgery was successful and she was admitted into postoperative recovery. However, the lack of adequate preoperative preparation caused traumatic reaction from the patient and her parents: anxiety over appearance, crying, refusal of oral fluids and oral care, refusal of analgesia, and refusal to mobilize. The patience and persistence of hospital staff slowly overcame all adversities and the patient moved on to full and successful recovery, but this case prompted changes in preoperative procedures and involvement of patients and their families in postoperative meal selection, planing, and preparation.

  8. Development of a HPLC-UV method for the quantitative determination of four short-chain fatty acids and lactic acid produced by intestinal bacteria during in vitro fermentation.

    Science.gov (United States)

    De Baere, S; Eeckhaut, V; Steppe, M; De Maesschalck, C; De Backer, P; Van Immerseel, F; Croubels, S

    2013-06-01

    A rapid and sensitive HPLC-UV method for the quantitative determination of four short-chain fatty acids (SCFAs) and lactic acid (LA) produced during in vitro fermentation is presented. Extraction of SCFAs from supernatants of bacterial cultures is aggravated due to their polarity and volatility. Detection can only be performed at a short, non-selective UV wavelength (210nm), due to the lack of any significant chromophore. Therefore special attention was paid to the optimization of the sample preparation procedure and the HPLC-UV conditions. The final extraction procedure consisted of a liquid-liquid back extraction using diethylether. Prior to HPLC-UV analysis the samples were acidified (pHacid, aiming to select for butyric acid-producing bacteria. In addition, the method has been used to determine the production pattern of selected fatty acids by bacterial species isolated from human feces and chicken caeca.

  9. Hydrophobicity measurements by HPLC: A new approach to. pi. constants

    Energy Technology Data Exchange (ETDEWEB)

    Gago, F.; Alvarez-Builla, J.; Elguero, J.

    1987-01-01

    A classical HPLC method of measuring log P/sub o/w/ has been reevaluated and applied to 107 different mono- and disubstituted benzenes. The contribution of several functional groups has been estimated through multiple regression analysis, obtaining statistically significant mean ..pi../sup *//sub m/ values. Deviations of experimentally determined log P/sup */ values for a set of ortho-, meta-, and para- disubstituted isomers from the ''simple additive'' model have been evaluated, and interpretations are suggested.

  10. Determination of selectivity of HPLC systems by correspondence factor analysis

    Institute of Scientific and Technical Information of China (English)

    Yuan Wang; Jun Yang; Xin Lu; Guo Wang Xu

    2007-01-01

    Correspondence factor analysis (CFA) was employed to study the selectivity of 14 HPLC systems, The tested LC systems were classified as reversed-phase (RP), ion-exchange (IE) and hydrophilic interaction chromatography (HILIC) modes. It was found that the retentions of the hydrophilic solutes on HILIC column were significantly influenced by the second-order effects besides their hydrophilic properties. Organic modifiers and residue silanol groups on silica surface both participated in retention. HypersilTM amino column performed separation in the HILIC mode at appropriate conditions, and its retention mechanism was more similar to that of HILIC silica column than that of HILIC column coating poly(aspartamide) groups.

  11. HPLC-Diode Array Detector Fingerprints of Various Mentha Species.

    Science.gov (United States)

    Hawrył, Mirosław A

    2014-01-01

    Gradient elution HPLC was applied to develop fingerprints of 12 extracts obtained from selected mint species. The gradient was optimized by use of Merck ChromSword computer software on the basis of retention data of some standard compounds occurring in the investigated plant material. Two column types (RP18 and pentafluorophenyl) and two mobile phases (methanol-water and acetonitrile-water) were used during the experiments. Fingerprints of all extracts were generated, and on the basis of the fingerprints identification of the mints was possible.

  12. Quantitative analysis of norfloxacin by 1H NMR and HPLC.

    Science.gov (United States)

    Frackowiak, Anita; Kokot, Zenon J

    2012-01-01

    1H NMR and developed previously HPLC methods were applied to quantitative determination of norfloxacin in veterinary solution form for pigeon. Changes in concentration can lead to significant changes in the 1H chemical shifts of non-exchangeable aromatic protons as a result of extensive self-association phenomena. This chemical shift variation of protons was analyzed and applied in the quantitative determination of norfloxacin. The method is simple, rapid, precise and accurate, and can be used for quality control of this drug.

  13. Stability-indicating HPLC method development and structural elucidation of novel degradation products in posaconazole injection by LC-TOF/MS, LC-MS/MS and NMR.

    Science.gov (United States)

    Yang, Yidi; Zhu, Xi; Zhang, Fei; Li, Wei; Wu, Ying; Ding, Li

    2016-06-05

    Stress testing was carried out under acidic, alkaline, oxidative, thermal and photolytic conditions to evaluate the intrinsic stability of posaconazole injection. A total of four degradation products were detected and the drug was found to be susceptible to oxidative and thermal degradations. Three unknown degradants formed under oxidative stress condition were isolated by preparative HPLC and unambiguously elucidated by LC-TOF/MS, LC-MS/MS, (1)H NMR, (13)C NMR and 2D NMR techniques. Based on the spectrometric and spectroscopic information, these novel degradation products were unequivocally assigned as the N-oxides of posaconazole. Probable mechanisms for the formation of the degradants were proposed. A new and selective HPLC method was developed and validated to separate, detect and quantify all the degradants in posaconazole injection.

  14. Scale-up synthesis and characterization of 2,6-diamino-3,5-dinitropyrazine-1-oxide

    Institute of Scientific and Technical Information of China (English)

    Hai-bin WANG; Yan-hong WANG; Yong-xiang LI; Yu-cun LIU

    2014-01-01

    2,6-diamino-3,5-dinitropyrazine-1-oxide (ANPZO), as an insensitive high explosive, with a high yield and excellent purity has been prepared at pilot plant scale by an improved method. The synthesized ANPZO is characterized by IR, laser granularity measurement, SEM and HPLC. The particle analysis revealed that the improved method could offer desired product with average particle size of 40 mm and high purity (>98.45%). The experimental parameters exhibited that the detonation velocity of the formulation based on ANPZO was higher than that of the corresponding TATB formulation. The DSC curve showed that the exothermic decomposition of the product occurred at the temperature between 300.5 ?C and 360.4 ?C. Furthermore, the sensitivity test suggests its safe nature towards mechanical stimulus.

  15. RP-HPLC Determination of 1,3-Dideoxygalactonojirimycin in Bombycis Faeces

    Institute of Scientific and Technical Information of China (English)

    QI Hui; ZHAO Hui; DING Zhen-ying; ZHU Yuan-yuan

    2011-01-01

    Objective To establish a simple and rapid method for the determination of 1,3-dideoxygalactonojirimycin in Bombycis Faeces, a potent glucosidase inihibitor, by HPLC. Methods A RP-HPLC method with fluorescence detection has been developed. Results The HPLC method developed in this research has a good reliability including accuracy and precision. The detection limit was less than 72 ng. Conclusion This method is sufficiently sensitive for determining 1,3-dideoxygalactonojirimycin in Bombycis Faeces and other related products.

  16. Determination of Selected Colored Smokes on Glass Fiber Discs by High Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    1991-05-01

    High Performance Liquid Chromatography (HPLC) 12. PERSONAL AUTHOR(S) F F_ n.ipl’prifl. Alan R...GROUP SUB-GROUP High Performance Liquid Chromatography (HPLC), Analytical IMethod, 1,4-diamino-2,3-dihydroanthraquinone, 2-(2 - _ quinolinyl)-1,3...weights, low vapor pressures and low thermal stability. High performance liquid chromatography (HPLC) appears to be the analytical method of choice

  17. Separation of antifungal chiral drugs by SFC and HPLC: a comparative study.

    Science.gov (United States)

    Bernal, J L; Toribio, L; del Nozal, M J; Nieto, E M; Montequi, M I

    2002-12-31

    The enantiomeric separation of several compounds, including an antifungal drug and several of its precursors, using HPLC and SFC is described in this work. The columns employed were based on polysaccharide derivatives and the results show that most of the separations obtained by SFC are better, in terms of high resolution and short analysis time, than those obtained by HPLC. Only one compound could not be resolved using SFC but, in this case, HPLC provided baseline resolution.

  18. RP-HPLC Determination of vitamins B1, B3, B6, folic acid and B12 in multivitamin tablets

    Directory of Open Access Journals (Sweden)

    SOTE VLADIMIROV

    2005-10-01

    Full Text Available Abstract:Asimple and sensitive reversed-phase, ion-pair HPLC method was developed and validated for the simultaneous determination of B-group vitamins, thiamine chloride hydrochloride (B1, nicotinamide (B3, pyridoxine hydrochloride (B6 and folic acid in Pentovit® coated tablets. The cyanocobalamine (B12 was determined separately, because of its low concentration in the investigated multivitamin preparation. RP-HPLC analysis was performed with a LKB 2150 HPLC system, equipped with a UV/VIS Waters M484 detector. The procedures for the determination of B1, B2, B6 and folic acid were carried out on a Supelcosil ABZ+ (15 cm 4.6 mm; 5 µm column with methanol-5mM heptanesulphonic acid sodium salt 0.1%triethylamine TEA(25:75 V/V; pH 2.8 as themobile phase. For the determination of B12 a Suplex pKb-100 (15 cm 4.6 mm; 5 µm column andmethanol–water (22:78 V/V as themobile phase were used. The column effluentsweremonitored at 290 nm for B 1, B3, B6 and folic acid, and at 550 nm for B12. The obtained results and statistical parameters for all the investigated vitamins of the B-group in Pentovit® coated tablets were satisfactory and ranged from 90.4 % to 108.5 % (RSD. from 0.5% to 4.1 %. The parameters for the validation of the methods are given.

  19. HPLC-based activity profiling for antiplasmodial compounds in the traditional Indonesian medicinal plant Carica papaya L.

    Science.gov (United States)

    Julianti, Tasqiah; De Mieri, Maria; Zimmermann, Stefanie; Ebrahimi, Samad N; Kaiser, Marcel; Neuburger, Markus; Raith, Melanie; Brun, Reto; Hamburger, Matthias

    2014-08-08

    Leaf decoctions of Carica papaya have been traditionally used in some parts of Indonesia to treat and prevent malaria. Leaf extracts and fraction have been previously shown to possess antiplasmodial activity in vitro and in vivo. Antiplasmodial activity of extracts was confirmed and the active fractions in the extract were identified by HPLC-based activity profiling, a gradient HPLC fractionation of a single injection of the extract, followed by offline bioassay of the obtained microfractions. For preparative isolation of compounds, an alkaloidal fraction was obtained via adsorption on cationic ion exchange resin. Active compounds were purified by HPLC-MS and MPLC-ELSD. Structures were established by HR-ESI-MS and NMR spectroscopy. For compounds 5 and 7 absolute configuration was confirmed by comparison of experimental and calculated electronic circular dichroism (ECD) spectroscopy data, and by X-ray crystallography. Compounds were tested for bioactivity in vitro against four parasites (Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani, and Plasmodium falciparum), and in the Plasmodium berghei mouse model. Profiling indicated flavonoids and alkaloids in the active time windows. A total of nine compounds were isolated. Four were known flavonols--manghaslin, clitorin, rutin, and nicotiflorin. Five compounds isolated from the alkaloidal fraction were piperidine alkaloids. Compounds 5 and 6 were inactive carpamic acid and methyl carpamate, while three alkaloids 7-9 showed high antiplasmodial activity and low cytotoxicity. When tested in the Plasmodium berghei mouse model, carpaine (7) did not increase the survival time of animals. The antiplasmodial activity of papaya leaves could be linked to alkaloids. Among these, carpaine was highly active and selective in vitro. The high in vitro activity could not be substantiated with the in vivo murine model. Further investigations are needed to clarify the divergence between our negative in vivo results

  20. HPLC-DAD-MS identification of bioactive secondary metabolites from Ferula communis roots.

    Science.gov (United States)

    Arnoldi, Lolita; Ballero, Mauro; Fuzzati, Nicola; Maxia, Andrea; Mercalli, Enrico; Pagni, Luca

    2004-06-01

    A simple HPLC method was developed to distinguish between 'poisonous' and 'non-poisonous' chemotypes of Ferula communis. The method was performed on a C8 reverse phase analytical column using a binary eluent (aqueous TFA 0.01%-TFA 0.01% in acetonitrile) under gradient condition. The two chemotypes showed different fingerprints. The identification of five coumarins and eleven daucane derivatives by HPLC-diode array detection (HPLC-DAD) and HPLC-MS is described. A coumarin, not yet described, was detected.

  1. Analysis of diglyceride concentration by HPLC-RID%HPLC-RID法甘油二酯含量分析

    Institute of Scientific and Technical Information of China (English)

    杨博; 李秋生; 杨继国; 李行方; 林炜铁

    2005-01-01

    研究了HPLC-RID法分析油脂中甘油二酯的含量,采用Nova-Pak(R)3.9 mm×150 mm硅胶柱,流动相为正已烷/异丙醇(50:1,V/V),12 min即可完成一个分析.应用外标法定量,该分析方法在1.0~10.0 mg/mL的浓度范围内线性良好,RSD为1.27%,平均回收率为101.9%.

  2. VALIDASI METODE ANALISIS KOLESTEROL DALAM TELUR DENGAN HPLC-ELSD

    Directory of Open Access Journals (Sweden)

    Hanifah Nuryani Lioe

    2013-12-01

    Full Text Available A method using high-performance liquid chomatography (HPLC coupled with an evaporative light-scattering detector (ELSD for the determination of cholesterol in egg was validated. A silica column and a binary mixture of hexane and isopropanol (90:10 as a mobile phase were used to separate cholesterol. Cholesterol was detected at 1.5 min using cholesterol standard and HPLC-ELSD condition: evaporation temperature 50 ºC, air pressure 2.2 bars, and flow rate of mobile phase 2 mL/min. A method linearity for the cholesterol analysis in egg as a sample matrix was obtained at a range of 50 to 3000 µg/g sample, with R2>0.990. Instrument detection limit and limit of quantitation were determined at 1.07 and 3.56 µg/mL, respectively. Recovery test results by spiking cholesterol standard in egg sample at low, medium, and high concentrations (50, 250 and 3000 µg/g were 122.13, 108.23, and 44.71%, respectively. Their corresponding repeatability values were 5.26, 4.29, and 10.11%. Method detection limit and intralab reproducibility (to analyze a sample were observed at 2.30 µg/g and 0.04%. The method is valid for cholesterol analysis in egg at low and medium concentrations.

  3. Pungency Quantitation of Hot Pepper Sauces Using HPLC

    Science.gov (United States)

    Betts, Thomas A.

    1999-02-01

    A class of compounds known as capsaicinoids are responsible for the "heat" of hot peppers. To determine the pungency of a particular pepper or pepper product, one may quantify the capsaicinoids and relate those concentrations to the perceived heat. The format of the laboratory described here allows students to collectively develop an HPLC method for the quantitation of the two predominant capsaicinoids (capsaicin and dihydrocapsaicin) in hot-pepper products. Each small group of students investigated one of the following aspects of the method: detector wavelength, mobile-phase composition, extraction of capsaicinoids, calibration, and quantitation. The format of the lab forced students to communicate and cooperate to develop this method. The resulting HPLC method involves extraction with acetonitrile followed by solid-phase extraction clean-up, an isocratic 80:20 methanol-water mobile phase, a 4.6 mm by 25 cm C-18 column, and UV absorbance detection at 284 nm. The method developed by the students was then applied to the quantitation of capsaicinoids in a variety of hot pepper sauces. Editor's Note on Hazards in our April 2000 issue addresses the above.

  4. Decomposition dynamic of higher plant pigments by HPLC analysis

    Institute of Scientific and Technical Information of China (English)

    LUO Yi; ZHANG Ting-zhou; ZHOU Qi-xing; MAO Da-qing; WAN Dong-mei

    2004-01-01

    The fate of the litter of dominant vegetation(willows and reeds) is one of the aspects studied in the frame of the project "Onderzoek Milieu Effecten Sigmaplan". One of the questions to be considered is how long the litter stays within the estuary. In this paper, the time the leaf litter(Salix triandra and Phragmites australis) stayed in the Schelde estuary was studied by using plant pigment as biomarkers with HPLC application. After analyzing the original data from the incubation experiment described by Dubuison and Geers(1999), the decomposition dynamics patterns of pigments were analyzed and described, and these decomposition dynamics patterns were used as calibration patterns. By using Spearman Rank Order Correlation, the calibration patterns of the pigments which were significant(p<0.05) were grouped. In this way, several groups of the calibration patterns of pigment decomposition were achieved. The presence or absence of these groups of pigments (whether they can be detected or not from HPLC) was shown to be useful in determining the time the litter has stayed in the water. Combining data of DW and POC, more precise timing can be obtained.

  5. HPLC assisted Raman spectroscopic studies on bladder cancer

    Science.gov (United States)

    Zha, W. L.; Cheng, Y.; Yu, W.; Zhang, X. B.; Shen, A. G.; Hu, J. M.

    2015-04-01

    We applied confocal Raman spectroscopy to investigate 12 normal bladder tissues and 30 tumor tissues, and then depicted the spectral differences between the normal and the tumor tissues and the potential canceration mechanism with the aid of the high-performance liquid chromatographic (HPLC) technique. Normal tissues were demonstrated to contain higher tryptophan, cholesterol and lipid content, while bladder tumor tissues were rich in nucleic acids, collagen and carotenoids. In particular, β-carotene, one of the major types of carotenoids, was found through HPLC analysis of the extract of bladder tissues. The statistical software SPSS was applied to classify the spectra of the two types of tissues according to their differences. The sensitivity and specificity of 96.7 and 66.7% were obtained, respectively. In addition, different layers of the bladder wall including mucosa (lumps), muscle and adipose bladder tissue were analyzed by Raman mapping technique in response to previous Raman studies of bladder tissues. All of these will play an important role as a directive tool for the future diagnosis of bladder cancer in vivo.

  6. [Determination method of polysorbates in powdered soup by HPLC].

    Science.gov (United States)

    Takeda, Y; Abe, Y; Ishiwata, H; Yamada, T

    2001-04-01

    A method for qualitative and quantitative analyses of polysorbates in powdered soup by HPLC was studied. Polysorbates in samples were extracted with acetonitrile after rinsing with n-hexane to remove fats and oils. The extract was cleaned up using a Bond Elut silica gel cartridge (500 mg). The cartridge was washed with ethyl acetate and polysorbates were eluted with a small amount of acetonitrile-methanol (1:2) mixture. The eluate was treated with cobalt thiocyanate solution to form a blue complex with polysorbate. In order to determine polysorbate, the complex was subjected to HPLC with a GPC column, using a mixture of acetonitrile-water (95:5) as a mobile phase, with a detection wavelength of 620 nm. The recoveries of polysorbate 80 added to powdered soups were more than 75% and the determination limit was 0.04 mg/g. When the proposed method was applied to the determination of polysorbates in 16 commercial samples of powdered soup for instant noodles and seasoning consomme, no polysorbates were detected in any sample.

  7. Selenite biotransformation during brewing. Evaluation by HPLC-ICP-MS.

    Science.gov (United States)

    Sánchez-Martínez, Maria; da Silva, Erik Galvão P; Pérez-Corona, Teresa; Cámara, Carmen; Ferreira, Sergio L C; Madrid, Yolanda

    2012-01-15

    Yeast (Saccharomyces cerevisiae) and lactic bacteria have shown their ability to accumulate and transform inorganic selenium into organo Se compounds. The objective of this work was to evaluate selenium biotransformation during brewing by using S. cerevisiae and Saccharomyces uvarum for Ale and Lager fermentation, respectively. Se-enriched beer was produced by the addition of sodium selenite (0, 0.2, 1.0, 2.0, 10.0, 20.0 μg Se mL(-1), respectively) to the fermentation media composed of yeast, malt extract and water. The alcoholic fermentation process was not affected by the presence of selenium regardless of the type of Saccharomyces being used. The percentage of selenium incorporated into beer, added between 1.0 and 10 μg mL(-1) was 55-60% of the selenium initially present. Se-compounds in post-fermentation (beer and yeast) products were investigated by using an analytical methodology based on HPLC-ICP-MS. For this purpose, several sample treatments, including ultrasonic-assisted enzymatic hydrolysis, in conjunction with different separation mechanisms like dialysis and anion exchange HPLC chromatography were applied for unambiguously identifying Se-species that produce during brewing. Selenomethionine was the main selenium compound identified in beer and yeast, being this species in the only case of the former not associated to peptides or proteins.

  8. Determination of lignans in edible and nonedible parts of pomegranate (Punica granatum L.) and products derived therefrom, particularly focusing on the quantitation of isolariciresinol using HPLC-DAD-ESI/MSn.

    Science.gov (United States)

    Fischer, Ulrike Anna; Jaksch, Ariane Verena; Carle, Reinhold; Kammerer, Dietmar Rolf

    2012-01-11

    A method for the characterization and quantitation of phyto-estrogenic lignans from pomegranate (Punica granatum L.) fruits and fruit-derived products by HPLC-DAD-MS(n) was developed. For this purpose, edible and nonedible parts of pomegranate (aril, peel, mesocarp, seed, and twigs), commercial juices, juices produced on pilot-plant scale, and encapsulated dietary supplements were analyzed. In addition to the peel, mesocarp, and twigs, lignans were detected in two juices obtained from entire fruits, four commercial juices, and three encapsulated pomegranate extracts. Isolariciresinol was the predominant lignan with contents of 5.0, 10.5, and 45.8 mg/kg dry matter in processed pomegranate mesocarp, peel, and twigs, respectively. In contrast, due to their low amounts, quantitation of lignans in pomegranate products was impossible. Therefore, contrary to previous assumptions, lignans were found to be less relevant in pomegranate-derived products. However, the byproduct from pomegranate processing may be used for lignan extraction. The method presented allows one to differentiate between pomegranate-derived products obtained from fruits without peels or by dejuicing applying low pressures, which were devoid of lignans, and those obtained from entire fruits applying high pressures, thus containing lignans. Consequently, this study helps to optimize process technology aiming at the recovery of preparations with well-desired compositions, which may reduce the risk of a wide range of diseases, such as certain types of cancer.

  9. Preparation of paclitaxel-loaded microspheres with magnetic nanoparticles

    Institute of Scientific and Technical Information of China (English)

    CUI Sheng; SHEN Xiaodong; SHI Ruihua; LIN Benlan; CHEN Ping

    2007-01-01

    The objective of this paper was to prepare paclitaxel-loaded microspheres,a kind of target-orientation anticancer drug.The paclitaxel-loaded microspheres were prepared with magnetic Fe3O4 nanoparticles and taxo1.The morphology was characterized by scanning electron microscopy(SEM),and the average size and the size distribution were determined by a laser-size distributing instrument.High performance liquid chromatography(HPLC)was used to measure the paclitaxel content.Experimental results indicated that the effective drug loading and the entrapment ratio of paclitaxel-loaded microspheres were 1.83% and 92,62%,respectively.

  10. [Preparation of recombinant human insulin--study of downstream process].

    Science.gov (United States)

    Yu, Rong; Li, Xiaohong; Yang, Jiyu; Wu, Wutong

    2004-10-01

    This study was intended to establish a method of preparation of recombinant human insulin, with (His)6-Arg-Arg-human proinsulin (RRhPI) expressed by Escherichia coli. After DEAE-Sepharose Fast Flow ion-exchange chromatography, Sephadex G-25 chromatography and refolding, enzyme cleavage and Superdex 75 size exclusion chromatography,the RRhPI expressed by Escherichia coli in inclusion body form was converted to human insulin. The obtained recombinant human insulin was analyzed by SDS-PAGE, HPLC, amino acid composition analysis and bioidentity test (mouse convulsion test). The results indicate that our obtained preparation is highly purified, active recombinant human insulin.

  11. Isolation and Preparative Purification for Ginkgolides A and B

    Institute of Scientific and Technical Information of China (English)

    韩金玉; 王华; 常贺英; 褚巧伟

    2003-01-01

    In this paper a simple preparative method for isolation and purification of ginkgolides A and B was developed,As starting material,a commercially available standardized ginkgo extract (EGb761,containing 24% flavonoid and 6% terpene trilactones) was used,After a pretreatment step,optimized by the uniform design method ,the concentrated intermediate extract with high content of GA and gb(+90%) was separated into the individual terpenes by preparative liquid chromatography eluted with petroleum ether-ethylacetate,Analysis of products was carried out by means of HPLC-ELSD(evaporative light -scattering detector),The results show that ginkgolides A and B are obtained in higher yield and better purity.

  12. Extraction of aflatoxins from liquid foodstuff samples with polydopamine-coated superparamagnetic nanoparticles for HPLC-MS/MS analysis.

    Science.gov (United States)

    McCullum, Cassandra; Tchounwou, Paul; Ding, Li-Sheng; Liao, Xun; Liu, Yi-Ming

    2014-05-14

    A facile magnetic solid phase extraction (MSPE) of aflatoxins (AFs) from liquid samples was developed using polydopamine-coated magnetic nanoparticles (PD-MNPs) as the adsorbent. PD-MNPs were prepared from amine-terminated MNPs and dopamine via an in situ oxidative self-polymerization approach. Under the selected MSPE conditions, extraction yields ranging from 59.3% for AF G2 to 89.0% for AF B1 were obtained with good repeatability. Coupled with HPLC-MS/MS quantification, the MSPE procedure serves not only for sample cleanup but also for AFs enrichment that is highly desired for trace analysis. The proposed MSPE-HPLC-MS/MS method had a linear calibration curve in the concentration range from 0.00600 to 3.00 ng/mL aflatoxin and limits of detection of 0.0012 ng/mL for AF B1, AF B2, and AF G1, and 0.0031 ng/mL for AF G2.

  13. Extraction of Aflatoxins from Liquid Foodstuff Samples with Polydopamine-Coated Superparamagnetic Nanoparticles for HPLC-MS/MS Analysis

    Science.gov (United States)

    2015-01-01

    A facile magnetic solid phase extraction (MSPE) of aflatoxins (AFs) from liquid samples was developed using polydopamine-coated magnetic nanoparticles (PD-MNPs) as the adsorbent. PD-MNPs were prepared from amine-terminated MNPs and dopamine via an in situ oxidative self-polymerization approach. Under the selected MSPE conditions, extraction yields ranging from 59.3% for AF G2 to 89.0% for AF B1 were obtained with good repeatability. Coupled with HPLC-MS/MS quantification, the MSPE procedure serves not only for sample cleanup but also for AFs enrichment that is highly desired for trace analysis. The proposed MSPE-HPLC-MS/MS method had a linear calibration curve in the concentration range from 0.00600 to 3.00 ng/mL aflatoxin and limits of detection of 0.0012 ng/mL for AF B1, AF B2, and AF G1, and 0.0031 ng/mL for AF G2. PMID:24766417

  14. [Determination of nabumetone and 6-methoxy-2-naphthylacetic acid in plasma using HPLC with UV and MS detection].

    Science.gov (United States)

    Nespesná, Lenka; Stícha, Martin; Matousková, Olga; Perlík, Frantisek; Slanar, Ondrej

    2011-02-01

    The study aimed to establish and validate an analytical method for the determination of nabumetone and 6-methoxy-2-naphthylacetic acid (6-MNA) in human plasma after a single therapeutic dose of the drug. Two methods based on HPLC with UV and MS detection were compared. Optimal results in sample preparation were achieved using solid phase extraction. The recovery reached approximately 84% and 86-90% for nabumetone and 6-MNA, respectively. A reverse C18 column was used for HPLC separation of the analytes. The limit of UV detection was 50 nM and 0.1 microM for 6-MNA and nabumetone, respectively. The limit of MS detection was 1 microM and 0.5 microM for 6-MNA and nabumetone, respectively. Precision ranged between 4.2-14.4% and 4.6-8.5% using UV and MS detection for nabumetone, respectively. The respective values for 6-MNA were 2.4-12.5% and 2.1-9.4%. Accuracy ranged between 93.4-109.6% in UV detection and 86.2-107.9% using UV and MS detection for nabumetone, respectively. The respective values for 6-MNA were 87.8-107.4% and 86.3-106.4%. The method was subsequently applied to determine the pharmacokinetic parameters of nabumetone and 6-MNA in a group of 24 healthy volunteers.

  15. HPLC analysis of midodrine and desglymidodrine in culture medium: evaluation of static and shaken conditions on the biotransformation by fungi.

    Science.gov (United States)

    Barth, Thiago; Aleu, Josefina; Pupo, Mônica Tallarico; Bonato, Pierina Sueli; Collado, Isidro G

    2013-01-01

    A high-performance liquid chromatography (HPLC) method is presented for the simultaneous determination of midodrine and desglymidodrine (DMAE) in Czapek-Dox culture medium, to be used in biotransformation studies by fungi. The HPLC analysis was conducted using a Lichrospher 100 RP18 column, acetonitrile-40 mmol/L formic acid solution (60:40, v/v) as mobile phase, and ultraviolet detection at 290 nm. The sample preparation was conducted by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 0.4-40.0 µg/mL for midodrine (r ≥ 0.9997) and DMAE (r ≥ 0.9998). Within-day and between-day precision and accuracy were evaluated by relative standard deviations (≤ 8.2%) and relative errors (-7.3 to 7.4%), respectively. The validated method was used to assess midodrine biotransformation by the fungi Papulaspora immersa Hotson SS13, Botrytis cinerea UCA 992 and Botrytis cinerea 2100 under static and shaken conditions. Under shaken conditions, the biotransformation of midodrine to DMAE was more efficient for all studied fungi, especially for the fungus Botrytis cinerea 2100, which converted 42.2% of midodrine to DMAE.

  16. Qualitative and quantitative analysis of chemical constituents of Centipeda minima by HPLC-QTOF-MS & HPLC-DAD.

    Science.gov (United States)

    Chan, Chi-On; Jin, Deng-Ping; Dong, Nai-Ping; Chen, Si-Bao; Mok, Daniel Kam Wah

    2016-06-05

    A high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) method in both positive and negative ion modes was established to investigate the major constituents in the ethanolic extract of Centipeda minima (EBSC). Twelve common components including flavones and their glycosides, phenolic and polyphenolic acids, and sesquiterpene lactone were identified in ten batches of samples based on comparison with the retention time and accurate mass of external standards (mass accuracy within 3ppm) or the fragmentation patterns of tandem MS. Meanwhile, a simple, accurate and reliable HPLC-DAD method was also developed to determine the content of 10 chemical markers simultaneously. Results obtained from method validations including linearity, accuracy and precision showed that this new method is reliable and robust. Isochlorogenic acid A and brevilin A were found to be the most abundant in the ethanol extract of EBSC and could be served as markers for quality control of EBSC. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Determination of some psychotropic drugs in serum and saliva samples by HPLC-DAD and HPLC MS.

    Science.gov (United States)

    Petruczynik, A; Wróblewski, K; Szultka-Młyńska, M; Buszewski, B; Karakuła-Juchnowicz, H; Gajewski, J; Morylowska-Topolska, J; Waksmundzka-Hajnos, M

    2016-08-05

    A simple, rapid and sensitive HPLC-DAD method has been developed and validated for the simultaneous determination of seven psychotropic drugs (risperidone, citalopram, clozapine,quetiapine, levomepromazine, perazine and aripiprazole) in human serum or saliva samples. The chromatographic analyses were performed on a XSELECT CSH Phenyl-Hexyl column with a mobile phase containing methanol, acetate buffer at pH 3.5 and 0.025mL(-1) diethylamine. The influence of concentration of methanol in injection samples and injection volume on peak symmetry and system efficiency was examined.The full separation of all investigated drugs, good peaks' symmetry and simultaneously high systems efficiency were obtained in applied chromatographic system. The method is suitable for the analysis of investigated drugs in human plasma or saliva for psychiatric patients for control of pharmacotherapy, particularly in combination therapy. HPLC-MS was applied for verification of the presence of drugs and their metabolites in serum and saliva samples from patients.

  18. Study on HPLC Fingerprint of Herba Lysimachiae%金钱草药材的HPLC指纹图谱研究

    Institute of Scientific and Technical Information of China (English)

    郭林林; 赵德; 邓君

    2012-01-01

    Objective: To establish the chromatographic fingerprint for Herba Lysimachiae by RP-HPLC. Methods: The sample solutions were prepared by extracting material with boiling water, followed by extracting with BuOH from the aqueous extract and analyzed by RP-HPLC with a Phenomenex C18 column(4. 6 mm × 150 mm,5 μm) ,gradiently eluted with A(acetonitrile containing 0.5 % of acetic acid) -B( water containing 0. 5 % of acetic acid) at 30℃ ,and monitored with UV detector at 255 nm. The flow rate was 1.0 mL/min,and sample volume injected was 20 μL. The chromatograms of different balches of Herba Lysimachiae were compared by the software of Similarity Evaluation System for Chromatographic Fingerprint of TCM( Version 2004A). Results: HPLC Fingerprint of Herba Lysimachiae was established with Rutin as the reference compound. 13 common peaks were selected as the fingerprint peaks of Herba Lysimachiae. Conclusion: The established HPLC fingerprint of Herba Lysimachiae has desirable precision, reproducibility, and can be applied to routine quality control of Herba Lysimachiae.%目的:建立金钱草药材的HPLC指纹图谱,为金钱草药材的质控提供依据.方法:用水煎-正丁醇萃取-甲醇溶解制备样品溶液,采用RP-HPLC分析,色谱条件为Phenomenex C18色谱柱(4.6 mm×150 mm,5 μm),以含0.5%冰醋酸的乙腈(A)-0.5%冰醋酸水(R)梯度洗脱,流速1.0 mL/min,柱温30℃,检测波长255 nm,进样量20μL.利用中药色谱指纹图谱相似度评价系统(2004A版)对不同批次金钱草药材的HPLC图进行比较分析.结果:建立了金钱草药材的HPLC指纹图谱,以芦丁为参照峰,确立了金钱草药材指纹图谱中的13个共有峰.结论:所建立的指纹图谱稳定性和重现性均好,可用于金钱草药材的常规质量控制.

  19. Segmental analysis for cocaine and metabolites by HPLC in hair of suspected drug overdose cases.

    Science.gov (United States)

    Clauwaert, K M; Van Bocxlaer, J F; Lambert, W E; De Leenheer, A P

    2000-06-05

    Hair samples of eight postmortem cases were analyzed in segments of 1 to 3 cm for cocaine, benzoylecgonine and cocaethylene. Samples were prepared for analysis by digestion in 0.1 M HCl and subsequent extraction with mixed-mode solid-phase extraction columns. Measurement was made by reversed-phase, narrow-bore HPLC and fluorescence detection using two laboratory-made internal standards. The concentrations were in the region of 0.29-316 ng/mg of hair for cocaine, 0.43-141 ng/mg of hair for benzoylecgonine and 0.93-1.83 ng/mg of hair for cocaethylene. All eight investigated cases had cocaine-positive segments. In six of the cases, all segments were positive, suggesting regular cocaine use and two showed in-between negative segments indicating an interruption or a change of the abuse intensity. The results showed a second, remarkable observation, i.e. enormous concentration differences (factor >150) for both cocaine and benzoylecgonine between the different subjects. Furthermore, interindividual cocaine/benzoylecgonine ratios ranged from 0.02 to 8.43. We believe these observations could in part be attributed to both some of the still existing limitations in the analytical approach(es), especially the mandatory hair washing steps, and in our still too limited knowledge of the hair incorporation processes. Nevertheless, in some cases, segmental analysis proved to be an important tool to distinguish, together with postmortem examination, deadly chronic abuse from single acute drug overdosage.

  20. Development and Validation of an HPLC Method for the Analysis of Sirolimus in Drug Products

    Directory of Open Access Journals (Sweden)

    Hadi Valizadeh

    2012-05-01

    Full Text Available Purpose: The aim of this study was to develop a simple, rapid and sensitive reverse phase high performance liquid chromatography (RP-HPLC method for quantification of sirolimus (SRL in pharmaceutical dosage forms. Methods: The chromatographic system employs isocratic elution using a Knauer- C18, 5 mm, 4.6 × 150 mm. Mobile phase consisting of acetonitril and ammonium acetate buffer set at flow rate 1.5 ml/min. The analyte was detected and quantified at 278nm using ultraviolet detector. The method was validated as per ICH guidelines. Results: The standard curve was found to have a linear relationship (r2 > 0.99 over the analytical range of 125–2000ng/ml. For all quality control (QC standards in intraday and interday assay, accuracy and precision range were -0.96 to 6.30 and 0.86 to 13.74 respectively, demonstrating the precision and accuracy over the analytical range. Samples were stable during preparation and analysis procedure. Conclusion: Therefore the rapid and sensitive developed method can be used for the routine analysis of sirolimus such as dissolution and stability assays of pre- and post-marketed dosage forms.

  1. HPLC determination of calcium pantothenate and two preservatives in topical cream.

    Science.gov (United States)

    Havlíková, L; Matysová, L; Nováková, L; Solich, P

    2006-05-03

    A RP-HPLC method for simultaneous determination of calcium pantothenate and two preservatives methylparaben and propylparaben present in topical cream was developed. Different analytical columns with various stationary phases were tested. During method development, Supelco Discovery C18 column (125 mmx4.0 mm, 5 microm) and Zorbax SB-CN column (150 mmx4.6 mm, 5 microm) were tested. Both were not convenient for analytical separation because of the co-elution of calcium pantothenate with dead volume, and problems with the peak-shape of all components. Good separation was achieved using Zorbax TSM (250 mmx4.6 mm, 5 microm) and Hypersil ODS column (250 mmx4.6 mm, 5 microm), the latter was finally used for the analysis. The analysis time was 12 min, at flow rate 0.7 ml min-1. Chromatography was performed using binary mobile phase composed of methanol and phosphoric acid, pH 2.5, 65:35 (v/v). UV detection was accomplished at 214 nm. The method was validated according to ICH guideline recommendations. The method is suitable for practical routine analysis of commercially produced topical pharmaceutical preparations.

  2. An HPLC-tandem mass spectrometry method for simultaneous detection of alkylated base excision repair products.

    Science.gov (United States)

    Mullins, Elwood A; Rubinson, Emily H; Pereira, Kevin N; Calcutt, M Wade; Christov, Plamen P; Eichman, Brandt F

    2013-11-01

    DNA glycosylases excise a broad spectrum of alkylated, oxidized, and deaminated nucleobases from DNA as the initial step in base excision repair. Substrate specificity and base excision activity are typically characterized by monitoring the release of modified nucleobases either from a genomic DNA substrate that has been treated with a modifying agent or from a synthetic oligonucleotide containing a defined lesion of interest. Detection of nucleobases from genomic DNA has traditionally involved HPLC separation and scintillation detection of radiolabeled nucleobases, which in the case of alkylation adducts can be laborious and costly. Here, we describe a mass spectrometry method to simultaneously detect and quantify multiple alkylpurine adducts released from genomic DNA that has been treated with N-methyl-N-nitrosourea (MNU). We illustrate the utility of this method by monitoring the excision of N3-methyladenine (3 mA) and N7-methylguanine (7 mG) by a panel of previously characterized prokaryotic and eukaryotic alkylpurine DNA glycosylases, enabling a comparison of substrate specificity and enzyme activity by various methods. Detailed protocols for these methods, along with preparation of genomic and oligonucleotide alkyl-DNA substrates, are also described.

  3. HPLC method validation for modernization of the tetracycline hydrochloride capsule USP monograph

    Directory of Open Access Journals (Sweden)

    Emad M. Hussien

    2014-12-01

    Full Text Available This paper is a continuation to our previous work aiming at development and validation of a reversed-phase HPLC for modernization of tetracycline-related USP monographs and the USP general chapter . Previous results showed that the method is accurate and precise for the assay of tetracycline hydrochloride and the limit of 4-epianhydrotetracycline impurity in the drug substance and oral suspension monographs. The aim of the current paper is to examine the feasibility of the method for modernization of USP tetracycline hydrochloride capsule monograph. Specificity, linearity, accuracy and precision were examined for tetracycline hydrochloride assay and 4-epianhydrotetracycline limit. The method was linear in the concentration range from 80% to 160% (r>0.9998 of the assay concentration (0.1 mg/mL for tetracycline hydrochloride and from 50% to 150% (r>0.997 of the acceptance criteria specified in tetracycline hydrochloride capsule monograph for 4-epianhydrotetracycline (NMT 3.0%. The recovery at three concentration levels for tetracycline hydrochloride assay was between 99% and 101% and the RSD from six preparations at the concentration 0.1 mg/mL is less than 0.6%. The recovery for 4-epianhydrotetracycline limit procedure over the concentration range from 50% to 150% is between 96% and 102% with RSD less than 5%. The results met the specified acceptance criteria.

  4. Immunoaffinity Ultrafiltration with Ion Spray HPLC/MS for Screening Small-Molecule Libraries.

    Science.gov (United States)

    Wieboldt, R; Zweigenbaum, J; Henion, J

    1997-05-01

    A solution-phase screening method for libraries of pharmaceutically relevant molecules is presented. The technique is applicable to screening combinatorial libraries of 20-30 closely related molecules. In this report, individual benzodiazepines are selected from a multicomponent library mixture by formation in solution of noncovalent immunoaffinity complexes with antibodies raised to therapeutically proven drugs such as nitrazepam, temazepam, or oxazepam. Captured compounds are separated from nonspecifically bound library components by centrifugal ultrafiltration. The specifically selected molecules retained on the filter are subsequently liberated from the antibodies by acidification and analyzed by HPLC coupled with pneumatically assisted electrospray (ion spray) ionization mass spectrometric detection. Competition by the benzodiazepines for limited antibody binding sites is controlled by varying the stoichiometry of the complexation mixture. This procedure selects library components with the greatest affinity for a particular antibody. Specific capture of benzodiazepines is demonstrated by screening both a pool of structurally similar benzodiazepines and a more complex mixture of benzodiazepines with an additional set of unrelated compounds. Affinity ultrafiltration and electrospray mass spectrometry complement each other to enhance screening and identification of pooled drug candidates and potentially can be extended to other small-molecule combinatorial libraries and macromolecular receptor preparations.

  5. Simultaneous determination of clobazam and its major metabolite in human plasma by a rapid HPLC method.

    Science.gov (United States)

    Rouini, Mohammadreza; Ardakani, Yalda H; Hakemi, Lida; Mokhberi, Maryam; Badri, Gheise

    2005-09-05

    A rapid and specific HPLC method has been developed and validated for simultaneous determination of clobazam, the anticonvulsant agent, and its major metabolite in human plasma. The sample preparation was a liquid-liquid extraction with tuloene yielding almost near 100% recoveries of two compounds. Chromatographic separation was achieved with a Chromolith Performance RP-18e 100 mm x 4.6mm column, using a mixture of a phosphate buffer (pH 3.5; 10mM)-acetonitrile (70:30, v/v), in isocratic mode at 2 ml/min at a detection wave-length of 228 nm. The calibration curves were linear (r(2)>0.998) in the concentration range of 5-450 ng ml(-1). The lower limit of quantification was 5 ng ml(-1) for two compounds studied. The within- and between-day precisions in the measurement of QC samples at four tested concentrations were in the range of 0.89-9.1% and 2.1-10.1% R.S.D., respectively. The developed procedure was applied to assess the pharmacokinetics of clobazam and its major metabolite following administration of a single 10mg oral dose of clobazam to healthy volunteers.

  6. Spectrophotometric and HPLC determination of deflazacort in pharmaceutical dosage forms

    Directory of Open Access Journals (Sweden)

    Amarilis Scremin

    2010-06-01

    Full Text Available Deflazacort (DFZ is a glucocorticoid used as an anti-inflammatory and immunosuppressant drug. No official methods are available for DFZ determination in pharmaceutical formulations. The objective of this study was to develop, validate and compare spectrophotometric (UV and colorimetric and high-performance liquid chromatography (HPLC methods, for the quantitative determination of DFZ in tablets and oral suspension. For the UV method, ethanol was used as the solvent, with detection at 244 nm. The colorimetric method was based on the redox reaction with blue tetrazolium in alkaline medium, with detection at 524 nm. The method by HPLC was carried out using a C18 column, mobile phase consisting of acetonitrile:water (80:20, v/v with a flow rate of 1.0 mL min-1 and detection at 244 nm. The methods proved linear (r > 0.999, precise (RSD 97%. Statistical analysis of the results indicated that the UV and HPLC methods were statistically equivalent, while the values obtained for the colorimetric method differed significantly from the other methods.O deflazacorte (DFZ é um fármaco glicocorticóide usado como antiinflamatório e imunossupressor. Métodos oficiais não estão disponíveis para a determinação de DFZ em formas farmacêuticas. Este estudo teve como objetivo desenvolver, validar e comparar métodos por espectrofotometria (UV e colorimetria e cromatografia líquida de alta eficiência (CLAE, na determinação quantitativa de DFZ em comprimidos e suspensão oral. O método por UV utilizou etanol como solvente, com detecção em 244 nm. O método colorimétrico foi baseado na reação de redução com azul de tetrazólio em meio alcalino, com detecção em 524 nm. O método por CLAE utilizou coluna C18; fase móvel constituída de acetonitrila:água (80:20, v/v, com fluxo de 1,0 mL min-1 e detecção em 244 nm. Os métodos foram lineares (r > 0,999; precisos (RSD 97%. As análises estatísticas dos resultados obtidos indicaram que os m

  7. Purification of six lignans from the stems of Schisandra chinensis by using high-speed counter-current chromatography combined with preparative high-performance liquid chromatography.

    Science.gov (United States)

    Zhu, Lijie; Li, Bin; Liu, Xiuying; Huang, Guohui; Meng, Xianjun

    2015-11-01

    A method for the preparative purification of lignans from Schisandra chinensis was established using a combination of high-speed counter-current chromatography (HSCCC) and preparative high-performance liquid chromatography (HPLC). The crude extracts obtained from S. chinensis by using 70% ethanol were separated on a macroporous resin column and then eluted with a graded ethanol series. A two-phase solvent system consisting of n-hexane-ethyl acetate-methanol-water (1:1:1:1, v/v) was used for HSCCC, and a mobile phase of acetonitrile-water (50:50, v/v) was used for preparative HPLC. The results obtained using HSCCC were compared with those obtained using preparative HPLC, and their advantages were further integrated to improve the separation efficiency. Six known lignans were identified by electrospray ionisation mass spectrometry and (1)H nuclear magnetic resonance (NMR) and (13)C NMR analyses; the purities of all the compounds were more than 91%.

  8. Analysis of brominated and phosphate-based flame retardants in polymer samples by HPLC-UV/MS and online-GPC-HPLC-UV

    Energy Technology Data Exchange (ETDEWEB)

    Schlummer, M.; Brandl, F. [Fraunhofer-Institut fuer Verfahrenstechnik und Verpackung (IVV), Freising (Germany); Maeurer, A.

    2004-09-15

    Here we present two analytical approaches for the identification and quantification of brominated and phosphate-based flame retardants. The first is an HPLC-UV/MS approach, which allows the separation and unequivocal identification and quantification of at least 15 different technical flame retardants. The second approach was set-up as a screening tool, consisting of a GPC separation coupled to an HPLC-UV device.

  9. Analysis of brominated and phosphate-based flame retardants in polymer samples by HPLC-UV/MS and online-GPC-HPLC-UV

    Energy Technology Data Exchange (ETDEWEB)

    Schlummer, M.; Brandl, F. [Fraunhofer-Institut fuer Verfahrenstechnik und Verpackung (IVV), Freising (Germany); Maeurer, A.

    2004-09-15

    Here we present two analytical approaches for the identification and quantification of brominated and phosphate-based flame retardants. The first is an HPLC-UV/MS approach, which allows the separation and unequivocal identification and quantification of at least 15 different technical flame retardants. The second approach was set-up as a screening tool, consisting of a GPC separation coupled to an HPLC-UV device.

  10. PRACTICAL PREPARATION OF RESVERATROL 3-O-β-D-GLUCURONIDE

    OpenAIRE

    Jungong, Christian S.; Novikov, Alexei V.

    2012-01-01

    A practical synthesis of resveratrol 3-O-β-D-glucuronide, suitable for preparation of large quantities, was developed using selective deacetylation of resveratrol triacetate with ammonium acetate. A simplified procedure for large scale preparation of resveratrol is also reported.

  11. PRACTICAL PREPARATION OF RESVERATROL 3-O-β-D-GLUCURONIDE

    OpenAIRE

    Jungong, Christian S.; Novikov, Alexei V.

    2012-01-01

    A practical synthesis of resveratrol 3-O-β-D-glucuronide, suitable for preparation of large quantities, was developed using selective deacetylation of resveratrol triacetate with ammonium acetate. A simplified procedure for large scale preparation of resveratrol is also reported.

  12. Preparation and Functional Exploration of Cysteine Peptides from Fresh Garlic Scales for Improving Bioavailability of Food Legume Iron and Zinc%鲜蒜嫩鳞被中半胱氨酸肽的制备及其对豆类铁锌生物利用率的影响

    Institute of Scientific and Technical Information of China (English)

    白冰; 陈琭璐; 李巧莲; 段亚琪; 刘玲; 檀德宏; 纪淑娟

    2014-01-01

    离子交换层析结合制备液相方法从鲜蒜嫩鳞被中制备2种半胱氨酸肽(γ-GCPs):( SC2 RC7)-γ-L-谷氨酰-S-烯丙基-L-半胱氨酸(1)和(SC2RC7)-γ-L-谷氨酰-S-丙基-L-半胱氨酸(2)。产物结构经HPLC-MS, CD和1 H NMR,13 C NMR分析并与标准品比对确定。利用体外模拟胃、肠消化实验检测其对豆类铁锌生物利用率的影响。结果表明,5 g豆粉中添加0.01 mmol的化合物1和化合物2分别使黄豆铁生物利用率从1.88%提高到6.73%和4.42%,绿豆铁生物利用率从2.52%提高到12.04%和9.38%;使黄豆锌生物利用率从13.37%提高到23.95%和20.58%,绿豆锌生物利用率从15.98%提高到28.44%和27.05%。%Two γ-glutamyl-cysteine peptides (γ-GCPs ) , ( SC2 RC7 )-γ-L-glutamyl-S-allyl-L-cysteine ( 1 ) and ( SC2 RC7 )-γ-L-glutamyl-S-propyl-L-cysteine ( 2 ) have been isolated from fresh garlic scales using ion-exchange chromatography and pre-HPLC. Their molecular structures were identified by HPLC-MS, CD, 1 H NMR, 13 C NMR, specific rotation and confirmed by the corresponding standard compounds. The influence of exogenously adding 1 and 2 on the bioavailability of iron and zinc from food legume was examined with soybean and mung bean, in the level of 0. 01 mmol/5 g of legume respectively. The enhancing effect of the two γ-GCPs of compound 1 and 2 on bioaccessibility of iron was generally evidenced in the case of soybean ( from 1 . 88% to 6 . 73% and 4 . 42%) and mung bean ( from 2 . 52% to 12 . 04% and 9 . 38%) . The two γ-GCPs similarly enhanced the bioaccessibility of zinc from the food legume, in soybean ranging from 13. 37% to 23. 95% and 20. 58%, and in mung bean from 15. 98% to 28. 44% and 27. 05%. Thus, both compounds 1 and 2 obviously had a promoting influence on the bioavailability of iron and zinc from food legumes. These findings are of practical value in a food-based strategy to enhance the bioavailability of trace minerals for human health.

  13. Theoretische en practische aspecten van het gebruik van micro-HPLC

    NARCIS (Netherlands)

    de Fluiter P; Jansen EHJM

    1992-01-01

    A practical and theoretical approach for the implementation of micro high performance liquid chromatography (HPLC) is described. A new simple and rapid test procedure was developed in wich a HPLC system can be validated for its suitability for micro-bore columns. It appeared that the detector flow

  14. Quantification of the molecular species of tetraacylglycerols in lesquerella (Physaria fendleri) Oil by HPLC and MS

    Science.gov (United States)

    Thirteen molecular species of tetraacylglycerols in the seed oil of Physaria fendleri were recently identified. We report here the quantification of these tetraacylglycerols using HPLC with evaporative light scattering detector and the MS of the HPLC fractions. Ion signal intensities of MS1 from th...

  15. Identification and Determination of Nicorandil and its Degradation Products by HPLC and GC/MS

    Institute of Scientific and Technical Information of China (English)

    Zhong Zhou CHENG; Ze Hui JIA; Yan CHEN; Li Ying CHEN; Hua LI

    2006-01-01

    A rapid and sensitive HPLC-DAD method is developed for simultaneous determination of nicorandil and its degradation products, N-(2-hydroxyethyl) nicotinamide, nitrate ion and nicotinic acid, using nicotinamide (NT) as internal standard, at wavelength 204 nm. Nicotinic acid is identified by HPLC and GC/MS. The method can also be applied to study kinetic of degradation processes of nicorandil in storage.

  16. Theoretische en practische aspecten van het gebruik van micro-HPLC

    NARCIS (Netherlands)

    de Fluiter P; Jansen EHJM

    1992-01-01

    A practical and theoretical approach for the implementation of micro high performance liquid chromatography (HPLC) is described. A new simple and rapid test procedure was developed in wich a HPLC system can be validated for its suitability for micro-bore columns. It appeared that the detector

  17. Size exclusion HPLC of proteins for evaluation of durum wheat quality

    Science.gov (United States)

    The present research aimed to assess size exclusion HPLC (SE-HPLC) in protein molecular weight distribution determination for quality evaluation of durum semolina. Semolina samples were milled from 13 durum genotypes grown at 7 locations in 2009 and 2010 in ND. Sodium dodecyl sulfate (SDS) buffer ...

  18. Chemical Profiling (HPLC-NMR & HPLC-MS, Isolation, and Identification of Bioactive Meroditerpenoids from the Southern Australian Marine Brown Alga Sargassum paradoxum

    Directory of Open Access Journals (Sweden)

    Robert Brkljača

    2014-12-01

    Full Text Available A phytochemical investigation of a southern Australian marine brown alga, Sargassum paradoxum, resulted in the isolation and identification of four new (5, 9, 10, and 15 and nine previously reported (1, 2, 6–8, and 11–14 bioactive meroditerpenoids. HPLC-NMR and HPLC-MS were central to the identification of a new unstable compound, sargahydroquinal (9, and pivotal in the deconvolution of eight (1, 2, 5–7, and 10–12 other meroditerpenoids. In particular, the complete characterization and identification of the two main constituents (1 and 2 in the crude dichloromethane extract was achieved using stop-flow HPLC-NMR and HPLC-MS. This study resulted in the first acquisition of gHMBCAD NMR spectra in the stop-flow HPLC-NMR mode for a system solely equipped with a 60 μL HPLC-NMR flow cell without the use of a cold probe, microcoil, or any pre-concentration.

  19. Comparative HPLC/ESI-MS and HPLC/DAD study of different populations of cultivated, wild and commercial Gentiana lutea L.

    Science.gov (United States)

    Mustafa, Ahmed M; Caprioli, Giovanni; Ricciutelli, Massimo; Maggi, Filippo; Marín, Rosa; Vittori, Sauro; Sagratini, Gianni

    2015-05-01

    The root of Gentiana lutea L., famous for its bitter properties, is often used in alcoholic bitter beverages, food products and traditional medicine to stimulate the appetite and improve digestion. This study presents a new, fast, and accurate HPLC method using HPLC/ESI-MS and HPLC/DAD for simultaneous analysis of iridoids (loganic acid), secoiridoids (gentiopicroside, sweroside, swertiamarin, amarogentin) and xanthones (isogentisin) in different populations of G.lutea L., cultivated in the Monti Sibillini National Park, obtained wild there, or purchased commercially. Comparison of HPLC/ESI-MS and HPLC/DAD indicated that HPLC/ESI-MS is more sensitive, reliable and selective. Analysis of twenty samples showed that gentiopicroside is the most dominant compound (1.85-3.97%), followed by loganic acid (0.11-1.30%), isogentisin (0.03-0.48%), sweroside (0.05-0.35%), swertiamarin (0.08-0.30%), and amarogentin (0.01-0.07%). The results confirmed the high quality of the G.lutea cultivated in the Monti Sibillini National Park.

  20. Purity determination of amphotericin B, colistin sulfate and tobramycin sulfate in a hydrophilic suspension by HPLC.

    Science.gov (United States)

    Pfeifer, Corina; Fassauer, Georg; Gerecke, Hagen; Jira, Thomas; Remane, Yvonne; Frontini, Roberto; Byrne, Jonathan; Reinhardt, Robert

    2015-05-15

    A suspension comprising of the three antibiotic substances amphotericin B, colistin sulfate and tobramycin sulfate is often used in clinical practice for the selective decontamination of the digestive tract of patients in intensive care. Since no detailed procedures, specifications or stability data are available for manufacturing this suspension, there may be discrepancies regarding formulation and stability of suspensions prepared in different pharmacies. The aim of this work is to develop a standardized formulation and to determine its stability under defined storage conditions. This would help guarantee that all patients receive the same preparation, therefore ensuring similar efficacy and improved safety. The first step in this process is to develop the required analytical tools to measure the content and purity of the drug substances in this complex mixture. In this paper, the development and validation of these tools as well as the development of the drug suspension formulation is described. The formulation comprises of Ampho-Moronal(®)-Suspension (Dermapharm) and a buffered, preservated aqueous solution of colistin sulfate and tobramycin sulfate. Two simple, well established high-performance liquid chromatography (HPLC) methods in the European Pharmacopoeia (EP) for impurity profiling of the two active ingredients amphotericin B and colistin sulfate were combined with a newly developed sample extraction procedure for the suspension. Sufficient selectivity and stability-indicating power have been demonstrated. Additionally, a new robust routine method was developed to determine possible degradation products of tobramycin sulfate in the investigated suspension. The specificity, precision, accuracy and linearity of the analytical procedures were demonstrated. The recovery rate was in the range of 90-110%. The precision results for the calculated impurities showed variation coefficients of <10%. The calibration curves were found to be linear with correlation

  1. HPLC analysis of diosgenin in three species of Costus

    Directory of Open Access Journals (Sweden)

    G.Sulakshana

    2014-11-01

    Full Text Available Medicinal plants form an essential part of indigenous pharmaceutical system. Costus species (Family: Costaceae, commonly called as spiral ginger or crepe ginger are important medicinal plants used in traditional system of medicine in India. These plants are used for their stimulant, carminative, diuretic, digestive and antiseptic properties. Some of the species of Costus are mainly used for treating diabetes. Species of Costus are known to contain a steroidal saponin- diosgenin as a major bioactive component, which is utilized as a precursor for the synthesis of various drugs. The present study is taken up to quantify the amount of diosgenin present in rhizomes and leaves of three species of Costus (C.pictus, C.speciosus and C.igneus using HPLC analysis.

  2. Determination of Diphenylamine in Agricultural Products by HPLC-FL.

    Science.gov (United States)

    Aoyagi, Mitsutoshi; Chiba, Masahiro; Kakimoto, Youichiro; Nemoto, Satoru

    2016-01-01

    A method for the determination of diphenylamine in agricultural products was developed. Diphenylamine was extracted with acetonitrile from a sample under an acidic condition, passed through a C18 cartridge column, re-extracted with n-hexane, cleaned up on a PSA cartridge column, determined by HPLC with fluorescence detector and confirmed by liquid chromatography with tandem mass spectrometry. Average recoveries (n=5) from brown rice, corn, soybeans, potato, cabbage, eggplant, spinach, orange, apple and green tea were in the range from 76.7 to 94.9%, and the relative standard deviations were from 0.6 to 5.8% at concentrations equal to the maximum residue limits (MRLs). The quantification limits were 0.01 mg/kg, which is the uniform limit in the positive list system for agricultural chemical residues in food in Japan.

  3. Determination of Acetonitrile Volume Fraction in Mobile Phase by HPLC

    Institute of Scientific and Technical Information of China (English)

    WU Yi; WANG Zhi-wu; GU Jing-kai; WANG Ying-wu

    2008-01-01

    This paper reports the development and validation of an assay for the determination of acetonitrile in the recycled mobile phase using high performance liquid chromatography(HPLC).The method is based on that the retention in reversed-phase liquid chromatography increases with decreasing concentration of organic phase in the mobile phase.The natural logarithm of the capacity ratio for a given solute is linearly related to the volume fraction of the organic modifier in the mobile phase.For dimethylphthalate and diethylphthalate,the linearity range is 30%--60%,and for biphenyl and terphenyl,the range is 60%-95%.Precision values(RSD) were both <1% and the accuracy(RE) was in the range of ±1%.The assay was successfully applied to the determination of acetonitrile concentration of recycled mobile phase after the distillation of the column eluent in our laboratory.

  4. Quality control of roots of Eleutherococcus senticosus by HPLC.

    Science.gov (United States)

    Apers, Sandra; Naessens, Tania; Van Miert, Sabine; Pieters, Luc; Vlietinck, Arnold

    2005-01-01

    An HPLC method based on several known methods for the determination of eleutherosides B and E was developed, optimised and validated in terms of linearity, precision (repeatability and intermediate precision on different days and at different concentration levels) and accuracy (recovery). The extraction procedure, the extraction solvent and the extraction yield were evaluated and optimised. A reversed-phase RP-18 column gradient eluted with a two-phase system consisting of phosphoric acid:water (0.5:99.5) and acetonitrile was used to evaluate the samples; detection was at 220 nm. Although eleutherosides B and E are commercially available, they are very costly, and therefore ferulic acid was chosen as external standard. The correction factors for the response of ferulic acid against both eleutherosides were determined and validated. This method, accepted by the European Pharmacopoeia Commission, will be included in the monograph on Eleutherococcus senticosus roots to assay the content of eleutherosides B and E.

  5. Determination of paclitaxel in southern yew tree by HPLC

    Institute of Scientific and Technical Information of China (English)

    施树云; 周春山

    2003-01-01

    Paclitaxel in southern yew tree was quantitatively determined by high performance liquid chromatography(HPLC) with ODS-C18 column. A mixture of CH3OH-H2O-CH3COOH(volume ratio: 55 : 44: 1) is used as mo-bile phase and UV detection is carried out at 227 nm, and the column temperature is 20℃. The results show thatthere is a good linear relationship between the area of paclitaxel and the concentration of the sample in the range 50-500 mg/L for paclitaxel. The corresponding regression equation is Y=13 021.7+ 1.01 × 106 X, r=0. 999 0. The av-erage recovery is 95. 3% and the relative standard deviation is 2.08%.

  6. Quantitative analysis of PMR-15 polyimide resin by HPLC

    Science.gov (United States)

    Roberts, Gary D.; Lauver, Richard W.

    1987-01-01

    The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

  7. [HPLC determination of the related substances in erdosteine].

    Science.gov (United States)

    Ma, Li; Zhang, Ling-di; Wang, Wen-na; Yao, Tong-wei

    2012-08-01

    An HPLC method was established for the determination of the related substance in erdosteine. Waters ODS-SunFire (250 mm x 4.6 mm ID, 5 microm) column was used, the mobile phase was composed of methanol-acetonitrile-0.01 mol x L(-1) citric acid (20:4:76, the pH value was adjusted by triethylamine to 2.5). The flow rate was 1 mL x min(-1). The detection wavelength was 254 nm. The related substances in the sample of erdosteine taken were calculated by self control with or without the response factor of impurity relative to that of erdosteine. Under the chromatographic condition developed, the impurities in erdosteine were isolated well. The detection limit was 0.2 microg x mL(-1) (signal/noise = 3) by principal component calculated. The method can be adopted to control the related substances in erdosteine.

  8. [Study on HPLC fingerprint chromatograms of Arisaematis Rhizoma].

    Science.gov (United States)

    Luo, Fen; Lu, Dan; Chi, Yumei; Wu, Hao; Yu, Hongli

    2011-12-01

    The fingerprint chromatograms of Arisaematis Rhizoma were established by HPLC. The analysis was performed on a Lichrospher C18 (4.6 mm x 200 mm, 5 microm) column with acetonitrile-water (containing 0.1% acetic acid) as mobile phase at a flow rate of 1.0 mL x min(-1). The detection wavelength was set at 270 nm, and the column temperature was 30 degrees C. The similarities of the fingerprint chromatograms were calculated over 0.9 between 11 batches of Arisaematis Rhizoma samples by analyzing 14 common peaks with adenosine as reference substance. However, their fingerprint chromatograms were significantly different from those of Pinellia pedatisecta and P. ternate. Adenine, hypoxanthine, xanthine, uridine, guanosine, adenosine, schaftoside, and isoschaftoside were identified by comparing the retention times and their ultraviolet spectra. The method is repeatable, exclusive and can be used for identification and evaluation of Arisaematis Rhizoma.

  9. A simple, rapid method for HPLC analysis of lycopene isomers.

    Science.gov (United States)

    Ishida, B K; Ma, J; Chan, B

    2001-01-01

    A rapid method for the extraction, separation and quantification of the geometric isomers of lycopene and beta-carotene from tomato fruit is described. Carotenoids in tomato were separated and eluted using a reversed-phase HPLC with a C30 column and a mobile phase consisting of methyl-t-butyl ether, methanol and ethyl acetate. The system provided sharp resolution of cis- and trans-isomers of lycopene within approximately 23 min in contrast to the longer and more complex gradient procedures required by previously described methods. Experiments indicate that the stability of extracts of fresh tomato may be improved if stored at -20 degrees C, and that the presence of the antioxidant BHA has no apparent effect on stability.

  10. A selective HPLC method for determination of lercanidipine in tablets.

    Science.gov (United States)

    Alvarez-Lueje, A; Pujol, S; Squella, J A; Núñez-Vergara, L J

    2003-02-05

    An HPLC reversed phase method using both UV (356 nm) and electrochemical (1000 mV) detection was developed in order to determine lercanidipine in commercial tablets. Repeatability and reproducibility were adequate. For quantification we have used the calibration plot method for lercanidipine concentration ranging between 1 x 10(-5) and 1 x 10(-4) M. Also, the proposed method is sufficiently selective to distinguish the parent drug and the degradation products after hydrolysis, photolysis or chemical oxidation. Furthermore, the typical excipients included in the drug formulation (talc, lactose, cornstarch, microcrystalline cellulose, carboxymethylcellulose and magnesium stearate) do not interfere with the selectivity of the method. Finally, the proposed chromatographic method was successfully applied to the quantitative determination of lercanidipine in commercial tablets.

  11. Quantitative analysis of PMR-15 polyimide resin by HPLC

    Science.gov (United States)

    Roberts, Gary D.; Lauver, Richard W.

    1987-01-01

    The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

  12. A Sensitive HPLC Technique for the Quantitation of Dauricine

    Institute of Scientific and Technical Information of China (English)

    CHEN Shujuan; YANG Yimei; ZHANG Li; PANG Xuebing; DAI Zongshun; ZENG Fandian

    2000-01-01

    To establish the determination method of dauricine (Dau) concentration in rats' blood and other biological samples, a reverse-phase HPLC method was adopted. Under the given condition, dauricine could be well separated. The retention time (tR) of Dau and its internal standard,daurisoline were 9.2 and 6.1 respectively. The detection limit was 10-2 mg/ml. The absolute recoveries of all kinds of samples were above 70%, and the relative ones were over 85%. A good liner relationship has been obtained over the entire range of 0.030 to 3.000 mg/L in blood samples and 0.050 to 5.000 mg/L in other tissue samples. The intraday and interday coefficients of variation were below 10%. The results showed that the method can be used for detecting Dau in all kinds of biological samples.

  13. Quantization of Dextromethorphan and Levocetirizine in Combined Dosage form Using a Novel Validated RP-HPLC Method

    Science.gov (United States)

    Joshi, Shalini; Bhatia, C.; Bal, C. S.; Rawat, M. S. M.

    2012-01-01

    The present study reveals a simple isocratic RP-HPLC method for the simultaneous determination of dextromethorphan hydrobromide and levocetirizine dihydrochloride in a cough syrup. The separation of these compounds was achieved within 10 min on a Phenomenex (USA) C18 analytical column, 250×4.0 mm i.d., using an isocratic mobile phase consisting of potassium dihydrogen phosphate buffer (pH 2.5) - acetonitrile- tetrahydrofuran (70:25:5, v/v/v). The analysis was performed at a flow rate of 1.2 ml/min and at a detection wavelength of 232 nm. Percentage recovery and RSD were 100.36% and 0.05% for levocetirizine dihydrochloride, 100.35% and 0.27% for dextromethorphan hydrobromide respectively. Quantification of the components in syrup formulation was calculated against the peak areas of freshly prepared standard solutions. The method was validated as per ICH guidelines. PMID:23204629

  14. Indirect competitive ELISA based on monoclonal antibody for the detection of 5-hydroxymethyl-2-furfural in milk, compared with HPLC.

    Science.gov (United States)

    Guan, Yongguang; Wu, Xinlan; Meng, Hecheng

    2013-08-01

    In this study, a method for rapid detection of 5-hydroxymethyl-2-furfural (HMF) was investigated. Monoclonal antibody (anti-HMF) was prepared and evaluated by an indirect competitive ELISA (ic-ELISA) format. The optimized standard curve was y=-0.2097x+1.0432 [where x is the logarithm (base 10) of the values of the HMF concentration and y is the absorbance of ic-ELISA results tested at 490 nm] and the linear detection range was 0.008 to 32.768 mg/L. The percentage of cross-reactivity of HMF with 5 major furfural derivatives was less than 2.92%. Finally, the established ic-ELISA format was used to test HMF in milk, and compared with the result obtained by HPLC, which produced an error of about 0.3%. Based on the data in this experiment, we concluded that the established ic-ELISA format was reliable with a high specificity.

  15. Development of a rapid and simple HPLC-UV method for determination of gallic acid in Schinopsis brasiliensis

    Directory of Open Access Journals (Sweden)

    Felipe H.A. Fernandes

    2015-06-01

    Full Text Available AbstractThe aim of this work was to develop and validate an analytical method for the identification of the chemical marker of Schinopsis brasiliensis Engl., Anacardiaceae. It would determine the total polyphenols and flavonoid content by spectrophotometric methodology in the dried extract of plant. The chromatographic profiles of S. brasiliensis were determined using HPLC-UV. The liquid chromatography method was conducted on a Phenomenex Gemini NX C18 column (250 × 4.6 mm, 5 μm. The mobile phase consisted of 0.05% orthophosphoric acid: methanol. The flow rate was 1 ml/min and effluents were monitored at 271 nm. The retention time for gallic acid was 8.5 min. The described method has the advantage of being both rapid and easy. Hence it can be applied for routine quality control analysis of herbal preparation containing S. brasiliensis.

  16. Simultaneous determination of nine components in Qingkailing injection by HPLC/ELSD/DAD and its application to the quality control.

    Science.gov (United States)

    Yan, Shikai; Luo, Guoan; Wang, Yiming; Cheng, Yiyu

    2006-03-01

    High-performance liquid chromatography coupled with photo diode array detection and evaporative light scattering detection (HPLC/DAD/ELSD) was established to simultaneously determine nine ingredients in Qingkailing injection. Four wavelengths at 240, 254, 280 and 330 nm, respectively, were chosen as the monitoring wavelength to determine two nucleosides (uridine and adenosine), geniposide, baicalin and two organic acids (chlorogenic acid and caffeic acid), and an evaporative light scattering detector combined was employed to determine three steroids (cholic acid, ursodeoxycholic acid and hyodeoxycholic acid). This assay was fully validated in respect to precision, repeatability and accuracy. The proposed method was successfully applied to quantify the nine ingredients in 19 different Qingkailing injection samples and by principal component analysis (PCA) and hierarchical clustering analysis (HCA), it demonstrated significant variations in the content of these compounds in the samples from different manufacturers and preparation procedures. This method could be readily utilized as a quality control method for traditional Chinese medicine (TCM).

  17. Quantization of dextromethorphan and levocetirizine in combined dosage form using a novel validated RP-HPLC method

    Directory of Open Access Journals (Sweden)

    Shalini Joshi

    2012-01-01

    Full Text Available The present study reveals a simple isocratic RP-HPLC method for the simultaneous determination of dextromethorphan hydrobromide and levocetirizine dihydrochloride in a cough syrup. The separation of these compounds was achieved within 10 min on a Phenomenex (USA C 18 analytical column, 250Χ4.0 mm i.d., using an isocratic mobile phase consisting of potassium dihydrogen phosphate buffer (pH 2.5 - acetonitrile- tetrahydrofuran (70:25:5, v/v/v. The analysis was performed at a flow rate of 1.2 ml/min and at a detection wavelength of 232 nm. Percentage recovery and RSD were 100.36% and 0.05% for levocetirizine dihydrochloride, 100.35% and 0.27% for dextromethorphan hydrobromide respectively. Quantification of the components in syrup formulation was calculated against the peak areas of freshly prepared standard solutions. The method was validated as per ICH guidelines.

  18. Identification of Rhodiola species by using RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    WANG Qiang; RUAN Xiao; JIN Zhi-hua; YAN Qi-chuan; TU Shan-jun

    2005-01-01

    An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to identify ten species ofRhodiola, R. coccinea A. Bor, R.junggarica C.Y. Yang et N.R. Cui spn., R. heterodonta A. Bor, R. linearifolia A.Bor, R. pamiro alaiucm A. Bor, R. kaschgarica A. Bor, R. litwinowii A. Bor, R. gelida schrenk, R. rosea L. and R. quadrifide Fisch et Mey collected from the Tianshan Mountains areas of China. Chromatograms of alcohol-soluble proteins, generated from these ten Rhodiola spp. were compared. Each chromatogram of alcohol-soluble proteins came from a single seed of one wild species only. The results showed that when using a Waters Delta Pak. C18, 5 μm particle size reversed phase column (150 mmnx3.9 mm),a linear gradient of 22%-55% solvent B with a flow rate of 1 ml/min and a run time of 67 min, the chromatography gave optimum separation of Rhodiola alcohol-soluble proteins. Chromatogram of each species was different and could be used to identify those species. Cluster analysis of genetic similarity coefficients of 37% to 60% showed a medium degree of genetic diversity among the species in these eco-areas. Cluster analysis showed that the ten species of Rhodiola can be divided into four clusters and yielded the general and unique biochemical markers of these species. RP-HPLC was shown to be a rapid, repeatable and reliable method for Rhodiola species identification and analysis of genetic diversity.

  19. Determination of rivaroxaban in patient’s plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS)

    Science.gov (United States)

    Derogis, Priscilla Bento Matos; Sanches, Livia Rentas; de Aranda, Valdir Fernandes; Colombini, Marjorie Paris; Mangueira, Cristóvão Luis Pitangueira; Katz, Marcelo; Faulhaber, Adriana Caschera Leme; Mendes, Claudio Ernesto Albers; Ferreira, Carlos Eduardo dos Santos; França, Carolina Nunes; Guerra, João Carlos de Campos

    2017-01-01

    Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p < 0.001). In addition, we validated hemolytic, icteric or lipemic plasma samples for rivaroxaban measurement by HPLC-MS/MS without interferences. The chromogenic and HPLC-MS/MS methods were highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels. PMID:28170419

  20. A direct comparison of the performance of ground, beaded and silica-grafted MIPs in HPLC and turbulent flow chromatography applications.

    Science.gov (United States)

    Fairhurst, Robert E; Chassaing, Christophe; Venn, Richard F; Mayes, Andrew G

    2004-12-15

    Spherical molecularly imprinted polymers (MIPs) specific to the beta-blocker propranolol have been synthesised using two different approaches and compared to traditional ground monolithic MIPs in HPLC and TFC applications. TFC is a LC technique used for rapid extraction of compounds directly from complex matrices. It can be easily coupled to HPLC and MS for automation of an extraction/analysis procedure. Spherical MIP beads were produced using a suspension polymerisation technique and silica/MIP composite beads by grafting MIP to spherical silica particles using a surface-bound initiator species. Synthesis of both beaded and silica-grafted MIPs was more practical than using the traditional grinding method and yields of spherical particles of the required size between 80 and 100% were routinely achieved. Under HPLC conditions, beaded and ground MIP materials showed a degree of chiral separation for all of the nine beta-blockers tested. The beaded MIP, however, showed much better flow properties and peak shape than the ground material. Silica-grafted MIP showed some separation in five of the drugs and a large improvement in peak shape and analysis times compared with both ground and beaded MIPs. The materials prepared were also used in extraction columns for Turbulent Flow Chromatography (TFC). Although no imprinting effect was observed under typical TFC conditions, beaded polymer materials showed promise for use as TFC extraction columns due to the good flow properties and clean extracts obtained.

  1. Determination of the pseudoephedrine content in pharmaceutical formulations and in biological fluids using a microbore HPLC system interfaced to a microfluidic chemiluminescence detector.

    Science.gov (United States)

    Kadavilpparampu, Afsal Mohammed; Al-Lawati, Haider A J; Suliman, FakhrEldin O; Al Kindy, Salma M Z

    2015-12-01

    A novel automated precolumn derivatization followed by separation using liquid chromatography for the determination of pseudoephedrine (PSE) by a microfluidic chemiluminescence detector has been developed. An on-line derivatization procedure was utilized by converting PSE into a highly light emitting species in a Ru(bipy)3(2+)-peroxydisulphate chemiluminescence (CL) system by derivatizing it with a 1.0 M formaldehyde solution. The derivatized analyte was directly injected into a microbore high-performance liquid chromatography (HPLC) system coupled to an on-chip chemiluminescence detector. The newly developed highly selective, sensitive and fast HPLC-CL method was validated and successfully applied for the analysis of PSE in pharmaceutical formulations and a human urine sample. The selectivity of the method is not only due to the HPLC separation but is also due to the highly selective detection principle of the Ru(bipy)3(2+)-peroxydisulphate CL system used. There was no interference observed from the common preservatives and excipients used in pharmaceutical preparations, which did not show any significant CL signal. The retention time of PSE was less than 3 min, and the detection limits and quantification limits were found to be 5.7 and 26.0 µg L(-1), respectively. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Accurate quantification of total chromium and its speciation form Cr(VI) in water by ICP-DRC-IDMS and HPLC/ICP-DRC-IDMS.

    Science.gov (United States)

    Markiewicz, Barbara; Komorowicz, Izabela; Barałkiewicz, Danuta

    2016-05-15

    Two analytical procedures have been developed for the determination of total chromium (TCr) and its highly toxic species, i.e. Cr(VI) in water samples using the following methods: inductively coupled plasma dynamic reaction cell isotope dilution mass spectrometry (ICP-DRC-IDMS) and high performance liquid chromatography inductively coupled plasma dynamic reaction cell isotope dilution mass spectrometry (HPLC/ICP-DRC-IDMS). Spectral interferences, predominantly occurring in chromium determination, were removed using a dynamic reaction cell (DRC). The presented procedures facilitate the quantification of trace amounts - below 1 µg L(-1) of TCr and individual Cr species - in various water matrices including drinking water and still bottled water with different mineral composition. Special attention has been paid to the adequate preparation of isotopically enriched (53)Cr(VI) standard solution in order to avoid artifacts in chromium speciation. Both procedures were fully validated as well as establishing the traceability and estimation of the uncertainty of measurement were carried out. Application of all of the above mentioned elements and of the isotope dilution technique, which provides the highest quality of metrological traceability, allowed to obtain reliable and high quality results of chromium determination in water samples. Additionally, the comparison of two methods: HPLC/ICP-DRC-MS and HPLC/ICP-DRC-IDMS for Cr(VI) determination, was submitted basing on the validation parameters. As a result, the lower values for these parameters were obtained using the second method.

  3. Analysis of sterigmatocystin in cereals, animal feed, seeds, beer and cheese by immunoaffinity column clean-up and HPLC and LC-MS/MS quantification.

    Science.gov (United States)

    Marley, Elaine; Brown, Phyllis; Mackie, Jennifer; Donnelly, Carol; Wilcox, Joyce; Pietri, Amedeo; Macdonald, Susan

    2015-01-01

    A method is reported for the analysis of sterigmatocystin in various food and feed matrices using a commercial sterigmatocystin immunoaffinity column (IAC) for sample clean-up prior to HPLC analysis by UV with mass spectrometric detection (LC-MS/MS). Cereals (wheat, oats, rye, maize and rice), sunflower seeds and animal feed were spiked with sterigmatocystin at levels from 0.75 to 50 µg kg(-1) to establish method performance. Using acetonitrile/water extraction followed by IAC clean-up, and analysis by HPLC with detection at 325 nm, recoveries ranged from 68% to 106%, with repeatability from 4.2% to 17.5%. The limit of quantification with UV detection in these matrices was 1.5 µg kg(-1). For the analysis of beer and cheese the sample preparation prior to IAC clean-up was changed to accommodate the different properties of the matrix, prior to analysis by LC-MS/MS. For beer and cheese spiked at 5.0 µg kg(-1) the recoveries were 94% and 104%, and precision (RSDs) were 1.9% and 2.9% respectively. The limits of quantification by LC-MS/MS in beer and cheese were 0.02 and 0.6 µg kg(-1) respectively. The sterigmatocystin IAC was demonstrated to provide an efficient clean-up of various matrices to enable this mycotoxin to be determined by either HPLC with UV detection or LC-MS/MS.

  4. Development and validation of a RP–HPLC method for the quantization studies of metronidazole in tablets and powders dosage forms

    Directory of Open Access Journals (Sweden)

    Elena Gabriela Oltean,

    2011-12-01

    Full Text Available An isocratic high-performance liquid chromatography (HPLC procedure was developed for the quantitative determination of metronidazole in tablets and powders. HPLC separation was carried out by reversed phasechromatography on Kromasil C18 (250 mm x 4.6 mm i.e.; 5 ìm particle size, held in thermostat at 25°C. The mobile phase consisted of methanol/ 0.1% phosphoric acid aq. (20/80v/v, with a flow rate of 1 ml/min and with UV detection at 317 nm. In order to validate the method, the following parameters have been investigated: linearity (r2=0.9999, range, precision, accuracy, specificity, limit of detection and limit of quantification. The described method can be successfully applied for the analysis of the active pharmaceuticalcompound in tablets and powders. This paper aimed to develop and validate an HPLC sensitive applicable method to determine the quantity of metronidazole in tablets and powders, contributing to the quality and safety control of these types of pharmaceutical preparations.

  5. Determination of rivaroxaban in patient's plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS).

    Science.gov (United States)

    Derogis, Priscilla Bento Matos; Sanches, Livia Rentas; de Aranda, Valdir Fernandes; Colombini, Marjorie Paris; Mangueira, Cristóvão Luis Pitangueira; Katz, Marcelo; Faulhaber, Adriana Caschera Leme; Mendes, Claudio Ernesto Albers; Ferreira, Carlos Eduardo Dos Santos; França, Carolina Nunes; Guerra, João Carlos de Campos

    2017-01-01

    Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p HPLC-MS/MS without interferences. The chromogenic and HPLC-MS/MS methods were highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels.

  6. Preparation of {sup 188}Re-lanreotide peptide and its quality control

    Energy Technology Data Exchange (ETDEWEB)

    Mushtaq, A.; Pervez, S.; Haider, I. [Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan). Nuclear Chemistry Div.

    2000-07-01

    A simple method is described for the preparation of {sup 188}Re-Lanreotide, a radiolabeled synthetic peptide derived from an analogue of somatostatin, using Lanreotide (50 {mu}g) and stannous tartrate to which is added carrier-free {sup 188}Re. The radiolabeling has been carried out with {proportional_to}555 MBq (15 mCi) with a > 95% labeling efficiency and no need for subsequent purification. ITLC and HPLC techniques were employed for monitoring the stability and labeling yield. Radiolabeling results in one major peak when analyzed by reverse-phase (RP) HPLC. (orig.)

  7. Simultaneous Determination and Pharmacokinetic Study of Six Components in Rat Plasma by HPLC-MS/MS after Oral Administration of Acanthopanax sessiliflorus Fruit Extract

    OpenAIRE

    Peng Du; Mingdao Lei; Yu Liu; Shilin Yang

    2016-01-01

    A specific and reliable HPLC-MS/MS method was developed and validated for the simultaneous determination of protocatechuic acid (PCA), scopolin, (−)-pinoresinol-4,4′-di-O-β-d-glucopyranoside (PDG), acanthoside D, acanthoside B and hyperin in rat plasma for the first time. The analytes were separated on a C18 column (50 × 2.1 mm, 1.8 µm) and a triple-quadrupole mass spectrometer equipped with an electrospray ionization (ESI) source was used for detection. The rat plasma sample was prepared usi...

  8. Simultaneous determination of trace levels of 10 quinolones in swine, chicken, and shrimp muscle tissues using HPLC with programmable fluorescence detection.

    Science.gov (United States)

    Zhao, Sijun; Jiang, Haiyang; Li, Xuelian; Mi, Tiejun; Li, Cun; Shen, Jianzhong

    2007-05-16

    A HPLC method using a modified sample preparation procedure was optimized and validated for the quantification of 10 quinolones (QNs), including marbofloxacin, ciprofloxacin, norfloxacin, lomefloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, oxolinic acid, and flumequine, in swine, chicken, and shrimp tissues. In this method, only a small mass (residue limits (10 ng g-1) established in many countries. The method was also applied to the measurement of QN residues in commercial muscle samples. The results showed it was rapid, simple, sensitive, and suitable for use in food surveillance programs.

  9. Analysis of black carbon molecular markers by two chromatographic methods (GC-FID and HPLC-DAD)

    Science.gov (United States)

    Schneider, Maximilian P. W.; Smittenberg, Rienk H.; Dittmar, Thorsten; Schmidt, Michael W. I.

    2010-05-01

    The analysis of benzenepolycarboxylic acids (BPCA) as a quantitative measure for black carbon (BC) in soil and sediment samples is a well-established method [1, 2]. Briefly, the oxidation of polycondensated BC molecules forms seven molecular markers, which can be assigned to BC, and which subsequently can be quantified by GC-FID (gas chromatography with flame ionization detector). Recently this method has been refined for BC quantification in seawater samples measuring BPCA on HPLC-DAD (High performance liquid chromatography with diode array detector) [3]. However, a systematic comparison of BC as determined by both analytical techniques would be essential to the calculation of global BC budgets, but is lacking. Here we present data for the systematic comparison of the two BPCA methods, both for quantity and quality. We prepared chars under well-defined laboratory conditions. Chestnut hardwood chips and rice straw were pyrolysed at temperatures between 200 and 1000°C under constant N2 stream. The BC contents of the chars have been analysed using the BPCA extraction method followed by either GC-FID or HPLC-DAD quantification [4]. It appears that the GC-FID method yields systematically lower concentrations of BPCA in the chars compared to the HPLC-DAD method. Possible reasons for the observed difference are i) higher losses of sample material during preparation for GC-FID; ii) different quality of the linear regression used for quantification; iii) incomplete derivatisation of B5CA and B6CA, which is needed for GC-FID analysis. In a next step, we will test different derivatisation procedures (methylation with dimethyl sulfate or diazomethane, and silylation) for their influence on the GC-FID results. The aim of this study is to test if black carbon can be quantified in soil, sediment and water samples using one single method - a crucial step when attempting a global BC budget. References: [1] Brodowski, S., Rodionov, A., Haumeier L., Glaser, B., Amelung, W. (2005

  10. The comparative research on constituents of Radix Aconiti and its processing by HPLC quadrupole TOF-MS.

    Science.gov (United States)

    Wu, Jian; Hong, Bo; Wang, Jia; Wang, Xi; Niu, Sijia; Zhao, Chunjie

    2012-11-01

    Based upon the regulations stipulated by the State Food and Drug Administration of China, only the processed, detoxified tubers and roots of Aconitum are allowed to be administered orally, used in clinical decoctions and adopted as raw materials for pharmaceutical manufacturing, so the processing principle of preparation of Radix Aconiti is important for ensuring the Radix Aconiti praeparata quality. A simple approach was described for HPLC-Q-TOF-MS screening and identification of many of the aconitine alkaloids present in unprocessed Radix Aconiti and Radix Aconiti praeparata. To compare their fingerprints, the processing principle of preparation of Radix Aconiti was developed. Twenty-nine compounds and 26 compounds were assigned to aconitine alkaloids and tentatively identified by comparing accurate mass and fragments information with that of the authentic standards or by mass spectrometry analysis and retrieving the reference literature. The nonester alkaloids were almost the same. The diester diterpene alkaloids were decreased, the monoester-diterpene alkaloids were increased and lipo-alkaloids decreased obviously in the processing of the preparation. These transformed components could be regarded as potential chemical markers that can be used to distinguish between raw and processed herbs.

  11. Zip Codes, Boundary depicting the location of 5-digit zip code boundaries prepared from TIGER shapefiles., Published in 2008, 1:1200 (1in=100ft) scale, Noble County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Zip Codes dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Road Centerline Files information as of 2008. It is described as...

  12. Iriflophenone-3-C-glucoside from Cyclopia genistoides: isolation and quantitative comparison of antioxidant capacity with mangiferin and isomangiferin using on-line HPLC antioxidant assays.

    Science.gov (United States)

    Malherbe, Christiaan J; Willenburg, Elize; de Beer, Dalene; Bonnet, Susan L; van der Westhuizen, Jan H; Joubert, Elizabeth

    2014-03-01

    The benzophenone, iriflophenone-3-C-glucoside, was isolated from Cyclopia genistoides using a combination of fluid-fluid extraction, high performance counter-current chromatography (HPCCC) and semi-preparative high performance liquid chromatography (HPLC). The microplate oxygen radical absorbance capacity (ORAC) assay, with fluorescein as probe, was adapted for use in an on-line HPLC configuration. The method was validated using a mixture of authentic standards including iriflophenone-3-C-glucoside, and the xanthones, mangiferin and isomangiferin. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) was included in the mixture for calculation of Trolox equivalent antioxidant capacity (TEAC) values. Using the on-line HPLC-ORAC assay, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(+)) on-line assays, the antioxidant activity of iriflophenone-3-C-glucoside and isomangiferin was demonstrated for the first time. Iriflophenone-3-C-glucoside presented no radical scavenging ability against DPPH, but scavenged ABTS(+) and peroxyl radicals (TEACABTS of 1.04 and TEACORAC of 3.61). Isomangiferin showed slightly lower antioxidant capacity than mangiferin against DPPH (TEACDPPH of 0.57 vs. 0.62), but higher capacity against ABTS(+) (TEACABTS of 1.82 vs. 1.67) and peroxyl radical (TEACORAC of 4.14 vs. 3.69) than mangiferin. The on-line HPLC-ORAC assay was shown to be more sensitive for radical scavengers, but at the same time less selective for rapid radical scavengers than the DPPH assay.

  13. Determination of Dimethyl Sulfoxide (DMSO), Ethanol (ETOH), Formamide (F) and Glycerol/Formal (GF) by High Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    1989-01-30

    HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC...Classification) (U) Determination of Dimethyl Sulfoxide (DMSO), Ethanol, (ETOH), Formamide (F), and Glycerol/ Formal (GF) by High Performance Liquid Chromatography (HPLC...and 5). High performance liquid chromatography (HPLC) was the analytical method of choice for analyzing DMSO, ethanol, formamide and

  14. New HPLC-chemometric approaches to the analysis of isoflavones in Trifolium lucanicum Gasp.

    Science.gov (United States)

    Küçükboyacı, Nurgün; Güvenç, Ayşegül; Dinç, Erdal; Adıgüzel, Nezaket; Bani, Barış

    2010-09-01

    New HPLC-chemometric approaches were proposed for the simultaneous chromatographic quantification of daidzein, genistein, formononetin, and biochanin A in the samples consisting of the aerial parts of Trifolium lucanicum Gasp. (Leguminosae). Partial least squares and principal component regression algorithms were applied to the multiple chromatographic data set obtained by measuring at 240, 248, 256, and 264 nm to construct HPLC-partial least squares and HPLC-principal component regression calibrations. Chromatographic separation was carried out by using a mobile phase containing methanol, acetate buffer (pH=4.75) and acetonitrile (21:58:21, v/v/v) on the reversed phase column, Supelcosil™ LC-18 (15 cm×4.6 mm id). In addition, conventional HPLC based on the detection at a single wavelength was used for the determination of each compound in the extracts of T. lucanicum. The validity and applicability of the proposed HPLC-chemometric and conventional HPLC methods were performed by analyzing various synthetic plant samples. A good agreement was observed in the application of the proposed HPLC-chemometric tools to the synthetic and extracted samples of T. lucanicum.

  15. Large-scale preparation of human anti-third-party veto cytotoxic T lymphocytes depleted of graft-versus-host reactivity: a new source for graft facilitating cells in bone marrow transplantation.

    Science.gov (United States)

    Aviner, Shraga; Yao, Xin; Krauthgamer, Rita; Gan, Yehudit; Goren-Arbel, Rinat; Klein, Tirza; Tabilio, Antonio; McMannis, John D; Champlin, Richard; Martelli, Massimo F; Bachar-Lustig, Esther; Reisner, Yair

    2005-06-01

    Induction of donor type chimerism in mildly prepared hosts without graft-versus-host disease (GvHD) is a most desirable goal in bone morrow transplantation. We have recently demonstrated in a mouse model that donor veto cytotoxic T lymphocytes (CTLs) can facilitate the induction of donor type chimerism in sublethally irradiated recipients without causing GvHD if they are effectively depleted of alloreactivity against host cells by means of stimulation against a third party. We extend this approach to human cells, by preparing CTLs in two major steps: primary culture in the absence of interleukin 2, leading to death by neglect of antihost clones, and addition of interleukin 2 and subsequent dilution of antihost clones as a consequence of the expansion of the anti-third-party clones. CTLs prepared in this way specifically suppress host cytotoxic T cells directed against antigens of the donor, but not against fourth-party antigens, as demonstrated in a standard (51)Cr release assay. We conclude that human anti-third-party CTLs afford a new source of veto cells that are depleted of potential graft-versus-host-reactive clones. The cells generated by this approach could potentially be used to facilitate engraftment of allogeneic hematopoietic stem cells.

  16. Analysis of benzo[c]phenanthridine alkaloids in Eschscholtzia californica cell culture using HPLC-DAD and HPLC-ESI-MS/MS.

    Science.gov (United States)

    Son, Seok Young; Rhee, Hong Soon; Lee, Min Woo; Park, Jong Moon

    2014-01-01

    Effective HPLC-DAD and HPLC-ESI-MS/MS methods have been developed for the analysis of eight benzo[c]phenanthridine alkaloids (sanguinarine, chelirubine, macarpine, chelerythrine, dihydrosanguinarine, dihydrochelirubine, dihydromacarpine and dihydrochelerythrine), which are important metabolites in Eschscholtzia californica cell culture. By adopting a ternary gradient pump system, the dihydro-form alkaloids hardly separable from each other could be successfully separated, and all the target alkaloids could be simultaneously quantified with the LOD values of 0.01-0.79 μg/mL and the LOQ values of 0.03-3.59 μg/mL. This HPLC-DAD method was further confirmed by HPLC-ESI-MS/MS system in multiple reaction monitoring mode. Each separated HPLC peak was identified as the target alkaloid, showing its relevant ionized molecule and selected fragment ion. By applying the established method, alkaloid production during the E. californica cell culture could be successfully monitored and some valuable information on its metabolism could be deduced.

  17. A Large Scale Separation of Taxanes from the Bark Extract of Taxus yunnanesis and 1H- and 13C-NMR Assignments for 7-epi-10-Deacetyltaxol

    Institute of Scientific and Technical Information of China (English)

    薛军; 卜海山; 曹春阳; 吴厚铭; 陈建民

    2001-01-01

    A large-scale separation of paclitaxel from semi-purified bark extract of Taxus yunnanesis was investigated. The chromatographic behavior of paclitaxel and two close eluting analogues, cephalomannine and 7-epi-10-deacetyltaxol were sytematically studied on a C18 bonded phase column with different mobile phase in reverse phase mode. According to the notably different selectivity of the methanol and acetonitrile with water in the mobile phase and the most important requirement of capacity in preparative chromatography, the optimum suitably mobile phase used in a large-scale isolation of paclitaxel and 7-epi-10-deacetyltaxol on a preparative C18 column was given.Cephalomannine was eliminated by ozonolysis and after then separated throughout a normal phase silica column.The whole large-scale process for high purity paclitaxel from the bark extract of Taxus yunnanesis consisted of a preliminary purification with Biotage FLASH 150i systen based on a prepacked normal phase silica cartridge followed by using a C18 Nova-pakTM column in Waters PrepLCTM 4000 prepparative HPLC system. The structure of 7-epi-10-deacetyltaxol was elucidated by 2O NMR technologies of TOCSY, DQF-COSY,HMQC and HMBC, etc.

  18. Application of Pattern Recognition Method for Color Assessment of Oriental Tobacco based on HPLC of Polyphenols

    Directory of Open Access Journals (Sweden)

    Dagnon S

    2014-12-01

    Full Text Available The color of Oriental tobaccos was organoleptically assayed, and high performance liquid chromatography (HPLC of polyphenols was performed. The major tobacco polyphenols (chlorogenic acid, its isomers, and rutin, as well as scopoletin and kaempferol-3-rutinoside were quantified. HPLC polyphenol profiles were processed by pattern recognition method (PRM, and the values of indexes of similarity (Is,% between the cultivars studied were determined. It was shown that data from organoleptic color assessment and from PRM based on HPLC profiles of polyphenols of the cultivars studied are largely compatible. Hence, PRM can be suggested as an additional tool for objective color evaluation and classification of Oriental tobacco.

  19. Electrochemically Pretreated Carbon Microfiber Electrodes as Sensitive HPLC-EC Detectors

    Directory of Open Access Journals (Sweden)

    Zdenka Bartosova

    2012-01-01

    Full Text Available The paper focuses on the analysis and detection of electroactive compounds using high-performance liquid chromatography (HPLC combined with electrochemical detection (EC. The fabrication and utilization of electrochemically treated carbon fiber microelectrodes (CFMs as highly sensitive amperometric detectors in HPLC are described. The applied pretreatment procedure is beneficial for analytical characteristics of the sensor as demonstrated by analysis of the model set of phenolic acids. The combination of CFM with separation power of HPLC technique allows for improved detection limits due to unique electrochemical properties of carbon fibers. The CFM proved to be a promising tool for amperometric detection in liquid chromatography.

  20. Preparing for Surgery

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preparing for Surgery Home For Patients Search FAQs Preparing for Surgery ... Surgery FAQ080, August 2011 PDF Format Preparing for Surgery Gynecologic Problems What is the difference between outpatient ...

  1. Preparing for Surgery

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preparing for Surgery Home For Patients Search FAQs Preparing for Surgery ... Surgery FAQ080, August 2011 PDF Format Preparing for Surgery Gynecologic Problems What is the difference between outpatient ...

  2. Simultaneous determination of 12 coumarins in bamboo leaves by HPLC.

    Science.gov (United States)

    Wang, Shuying; Tang, Feng; Yue, Yongde; Yao, Xi; Wei, Qi; Yu, Jin

    2013-01-01

    A simple, rapid, and sensitive HPLC-UV method was developed for qualitative and quantitative analysis of 12 coumarin compounds (skimin, scopolin, scopoletin, umbelliferone, 6,7-dimethoxycoumarin, coumarin, psoralen, xanthotoxin, 5,7-dimethoxycoumarin, pimpinellin, imperatorin, and osthole) in bamboo leaves. The samples were extracted with ethanol-water (70 + 30, v/v) by ultrasonication and purified by Florisil SPE. The method was validated for linearity, LOD, LOQ, accuracy, precision, and recovery. The standard curves in the corresponding ranges had good linearity. LOD was at the range of 0.19 to 0.85 mglkg and LOQ 0.64 to 2.82 mg/kg. The values of RSD for accuracy and intraday and interday precision were less than 3%, except for 6,7-dimethoxycoumarin. Recoveries from spiked samples at 30, 20, and 10 mg/kg in Dendrocalamus giganteus Munro were higher than 70%, except for scopoletin, 6,7-dimethoxycoumarin, and coumarin. The method was validated using field-collected samples taken from Beijing and Changning Counties, SiChuan, China. Six coumarins, namely, skimin, scopolin, scopoletin, umbelliferone, coumarin, and pimpinellin, were found in the extracts of 11 species of bamboo leaves. The concentrations of total coumarins were in the range of 8.67 to 99.2 mg/kg. The maximum concentration of total coumarins was found in Bambusa pervariabilis, and the minimum was in

  3. HPLC determination of valproic acid in human serum.

    Science.gov (United States)

    Kishore, P; Rajani Kumar, V; Satyanarayana, V; Krishna, D R

    2003-06-01

    A HPLC method for the determination of valproic acid (VA) in human serum using diazepam as internal standard (I.S.) is described. The eluates were separated with a C18 250 x 4.6 mm internal diameter reversed phase column maintained at a temperature of 50 degrees C. A mobile phase consisting of acetonitrile and 0.05 M phosphate buffer (pH 3.0) 45:55 v/v was used at a flow rate of 1.2 ml/min. Wavelength was switched from 360 nm to 210 nm during valproic acid retention. The method was linear over a concentration range of 20 to 160 microg/ml for valproic acid. Recovery was greater than 94% over a concentration range of 20 to 120 microg/ml and the limit of quantitation was 1 microg/ml. The intra day and inter day relative standard deviation (R.S.D.) measured at 20, 60, 80 and 120 microg/ml ranged from 1.46 to 5.34% and 0.83 to 5.03% respectively. The method is simple, rapid, accurate and sensitive and it was used for Therapeutic Drug Monitoring (TDM) in Indian epileptic patient population. The results obtained with this method correlated well with clinical practice.

  4. Determination of paraquat in vegetables using HPLC-MS-MS.

    Science.gov (United States)

    Zou, Tingting; He, Pingli; Cao, Jingjing; Li, Zhen

    2015-02-01

    A simple, sensitive, reliable and economical method was developed for the determination of paraquat (a widely used herbicide) in four edible vegetables (cabbage, lettuce, spinach and Chinese cabbage) using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS). The samples were extracted with water under sonication and cleaned up by weak cation exchange solid-phase extraction. Chromatographic separation of paraquat was achieved on a hydrophilic interaction liquid chromatography column (2.1 × 100 mm, 3 µm) with a gradient program using 10 mM ammonium acetate in 0.1% formic acid and acetonitrile as mobile phase. The low salt concentration used in the eluting buffer ensured extended LC-MS analysis of paraquat in different matrices without the necessity of frequent source cleaning. The validity of the developed method was evaluated by spiking paraquat in four edible vegetables at 50 and 500 ng g(-1). Recovery ranged from 43.6 to 73.5%. The limit of detection is 0.94 ng g(-1). With the developed method, the kinetic of paraquat entering plant tissue was also evaluated.

  5. Simplified micromethod for the HPLC measurement of diclofenac in plasma.

    Science.gov (United States)

    Santos, S R; Donzella, H; Bertoline, M A; Pereira, M D; Omosako, C E; Porta, V

    1992-01-01

    A simple and sensitive micromethod based on HPLC is described for the measurement of diclofenac in 200 microliters plasma. A single extraction with dichloromethane in acidic medium was an essential clean-up step. Diclofenac and its internal standard (cyclohexendiphenyl propionic acid) was eluted at 3.3 and 6.5 min from a 4-micron C18 reverse-phase column using a mobile phase consisting of 0.75 M sodium acetate buffer, pH 5.0, and acetonitrile (55:45, v/v) at a flow rate of 0.9 ml/min with detection at 282 nm. The method, validated on the basis of parameters evaluated for the confidence limits of diclofenac measurements in spiked plasma, presented 1 ng/ml sensitivity, 10-10,000 ng/ml linearity, and 3.5% and 5.7% intra- and interassay precision, respectively. Peak plasma diclofenac levels ranging from 177 to 841 ng/ml and from 276 to 1008 ng/ml were obtained for two slow-release formulations. A wide range (1 ng/ml-3 micrograms/ml) was observed for plasma diclofenac levels of volunteers during a 24-h study period.

  6. Some aspects regarding impurities profile in fipronil-HPLC method

    Directory of Open Access Journals (Sweden)

    Ana Csuma,

    2011-12-01

    Full Text Available Using a substance as active pharmaceutical ingredient in veterinary drug formulation requires the characterization of this substance as content in active compound and so in terms of impurities possiblepresent in it, the latter being a mandatory requirement for a drug application. Fipronil is a synthetic product belonging to pesticide class used in veterinary practice to manufacture of some products against fleas, given spot–on or in form of spray, in cats and dogs. The main impurities in fipronil include process related impuritiesand degradation products as a result of exposure to environmental conditions: reduction, oxidation, photolysis and hydrolysis. A HPLC method suitable for analytical separation of fipronil from its impurities was established. Separation was achieved on a reversed phase column using a mixture of methanol, acetonitrile and water as mobile phase. In the chosen chromatographic conditions the resolution between fipronil and its sulphone (the main impurity was > 3 and the tailing factor (T < 2.0. Related impurities have absorbed in thesame band of UV wavelength as the main compound fipronil. Comparing the area of impurities obtained for sample solution with the area of the main peak in diluted standard solution allowed the detection of impurities at concentration < 0.1 %. Chromatographic separation on the same analytical column and detection at 280 nm was validated for assay of the content of active substance in fipronil used as ingredient in drug formulations.

  7. Strong cation exchange monoliths for HPLC by Reactive Gelation.

    Science.gov (United States)

    Brand, Bastian; Krättli, Martin; Storti, Giuseppe; Morbidelli, Massimo

    2011-08-01

    Polymeric monolithic stationary phases for HPLC can be produced by Reactive Gelation. Unlike the conventional method of using porogens, such novel process consists of a number of separate steps, thus enabling a better control of the quality of the final material. A suspension of polymer nanoparticles in water is produced and subsequently swollen with hydrophobic monomers. The particles are then destabilised (usually by salt addition) to make them aggregate into a large percolating structure, the so-called monolith. Finally, the added monomer can then be polymerised to harden the structure. In this work, a polystyrene latex is used as the base material and functionalised by introduction of epoxide groups on the surface and subsequent reaction to sulphonic acid groups, yielding a SO3(-) density of 0.7 mmol/g dry material. Morphological investigations show 54% porosity made of 300 nm large pores. Van Deemter measurements of a large protein show no practical influence of diffusion limitations on the plate number. Finally, a preliminary separation of a test protein mixture is shown, demonstrating the potential of using ion-exchange chromatography on Reactive Gelation monoliths.

  8. Exclusion and retention of compensatory kosmotropes by HPLC columns.

    Science.gov (United States)

    Lever, M

    1998-09-16

    With water as the elution solvent, zwitterionic solutes and polyols were retained on HPLC columns, more than was water, by totally hydrophobic packing materials. Relative retentions were systematically affected by oxygen functional groups in the packing material, explicable as specific retention of water. Reproducible elution sequences of 20 solutes at a variety of hydrophobic surfaces (aromatic and both long- and short-alkyl aliphatic surfaces) showed there is a general process, consistent with interactions with hydration water at the surface having solvent properties distinct from bulk water. Early eluting solutes included glycine, sarcosine and taurine. Glycine betaine followed both these and N,N-dimethylglycine. The natural betaines propionobetaine and dimethylsulfoniopropionate also preceded glycine betaine. Dimethylsulfoxide was strongly retained, as (to a lesser extent) was proline betaine. Polyols eluted in the sequence sorbitol, trehalose, glycerol. Changes in the chemical nature of the surface or base material affected relative retentions of water and solutes. The presence of hydrogen-bonding functions increased retention of polyols, as well as water, relative to zwitterionic solutes. Specific effects retention, constraining models based on the formation of low-density water.

  9. Characterization of petroleum heavy distillates using HPLC and spectroscopic methods

    Energy Technology Data Exchange (ETDEWEB)

    Sarowha, S.L.S.; Sharma, B.K.; Sharma, C.D.; Bhagat, S.D. [Indian Institute of Petroleum, Dehradun (India)

    1997-05-01

    Petroleum heavy distillates find wide application as feedstocks for upgrading through secondary conversion processes. Compositional data on such feedstocks provide useful information to the refiners for selecting processing parameters to achieve product selectivity, quality, and yield. A HPLC method has been optimized to estimate hydrocarbon group types in five lubricating oil base stocks using refractive index (RI) and UV detectors. Data generated at two wavelengths (210 and 254 nm) indicated best results for monoaromatics at 210 nm due to enhanced response and compared well with mass spectrometry data. RI data revealed that saturate content decreases from spindel oil (56%) to heavy oil (42%) which is corroborated by MS data measured for three samples. NMR data exhibited that light oil is more paraffinic (63%) in nature as indicated by branchiness index (0.478). UV data revealed an increasing trend of monoaromatics from spindle (16%) to deasphalted oil (DAO) (20%) and this is supported by MS data, while DAO and heavy oil indicated higher values of diaromatics. 17 refs., 1 fig., 7 tabs.

  10. HPLC retention thermodynamics of grape and wine tannins.

    Science.gov (United States)

    Barak, Jennifer A; Kennedy, James A

    2013-05-08

    The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality.

  11. New validated method for piracetam HPLC determination in human plasma.

    Science.gov (United States)

    Curticapean, Augustin; Imre, Silvia

    2007-01-10

    The new method for HPLC determination of piracetam in human plasma was developed and validated by a new approach. The simple determination by UV detection was performed on supernatant, obtained from plasma, after proteins precipitation with perchloric acid. The chromatographic separation of piracetam under a gradient elution was achieved at room temperature with a RP-18 LiChroSpher 100 column and aqueous mobile phase containing acetonitrile and methanol. The quantitative determination of piracetam was performed at 200 nm with a lower limit of quantification LLQ=2 microg/ml. For this limit, the calculated values of the coefficient of variation and difference between mean and the nominal concentration are CV%=9.7 and bias%=0.9 for the intra-day assay, and CV%=19.1 and bias%=-7.45 for the between-days assay. For precision, the range was CV%=1.8/11.6 in the intra-day and between-days assay, and for accuracy, the range was bias%=2.3/14.9 in the intra-day and between-days assay. In addition, the stability of piracetam in different conditions was verified. Piracetam proved to be stable in plasma during 4 weeks at -20 degrees C and for 36 h at 20 degrees C in the supernatant after protein precipitation. The new proposed method was used for a bioequivalence study of two medicines containing 800 mg piracetam.

  12. Countercurrent chromatographic with upright multilayer coil plante centrifuge for large-scale preparation%一种用于大容量逆流色谱制备的立式多层螺旋管行星式离心机

    Institute of Scientific and Technical Information of China (English)

    吴世华; 孙翠荣; 戴元柏; 周慧; 潘远江; 张虹

    2003-01-01

    Owing to no complications caused by solid supports, such as adsorptive sample loss and deactivation, tailing of solute peaks, and contamination, countercurrent chromatography (CCC) has been an area of intense research since the first introduction of CCC in 1970,[1] and various apparatus and broad applications have been advanced[2,3]. For these developments, the type-J synchronous planet centrifuge has received considerable attention, which relies not only on its relatively simple mechanic design, but also on its high partition efficiency and short elution time caused by mixing and settling for the efficient chromatographic separations. In the past, however, almost all of type-J centrifuges rotated slowly were disposed horizontally due to the original design and some experiments that gravis plays an important role at a low rotary speed as similar to type-V rotating multilayer helical tube in unit gravity[4-9]. In fact,we discovered that the upright apparatus holds more retention of stationary phase than the horiziontal aparatus when large standard tubings were used as mutilayer coil column and the aparatus was operated under same contions. We report here a new coil planet centrifuge with four upright cylindrical columns for large scale countercurrent chromatographic preparation. The design principle and apparatus of UCCC is as samilar to type-J multilayer coil planet centrifuge. Four uptight cylindrical column holders are symmetrically arranged around the centrifuge axis as similar to the type-J HSCCC with three horizontal multilayer coils connected in series[8] . A series of experiments indicat that upright CCC has many advantages over the horizontal CCC when using a large-bore tube as multilayer coil column for large scale countercurrent chromatographic separation.Upright CCC provide a versatile countercurrent chromatographic method for large-scale preparation from very crude sample. It has good preparative capacity and flexible suitability to various sample and

  13. Extractability of Rutin in Herbal Tea Preparations of Moringa stenopetala Leaves

    Directory of Open Access Journals (Sweden)

    Solomon Habtemariam

    2015-08-01

    Full Text Available The study examined the comparative rutin contents and antioxidant potentials of the two closely related Moringa species: the Ethiopian (Moringa stenopetala and Indian Moringa (M. oleifera. It is demonstrated that M. stenopetala leaves extract was a far superior (more than five-fold better antioxidant than M. oleifera. Rutin was the principal constituent of M. stenopetala leaves while the compound was not detected in the leaves of M. oleifera. Quantitative HPLC-based analysis of M. stenopetala leaves revealed the rutin level at a respectable 2.34% ± 0.02% (on dry weight basis, which is equivalent to many commercial natural sources of this highly sought-after bioactive compound. Comparative analysis of rutin in some common herbal tea preparations of M. stenopetala leaves revealed that it is readily extractible with the highest amount obtained (98.8% ± 2.4% when the leaves (1 g were boiled in water (200 mL. For a large-scale exploitation of rutin, a fast and economically-viable isolation approach using solid phase extraction followed by crystallization or flash chromatography is outlined. Overall, the Ethiopian Moringa is distinctively different from the Indian Moringa and could be exploited as an industrial source of rutin for nutritional and/or medical uses.

  14. HPLC Fingerprint of Huoxiang Zhengqi Mixture%藿香正气合剂的 HPLC 指纹图谱研究

    Institute of Scientific and Technical Information of China (English)

    林雀跃; 张荣林; 罗轶; 张慧

    2016-01-01

    目的:建立藿香正气合剂的 HPLC 指纹图谱。方法:样品直接进样,以橙皮苷为参照峰,通过紫外检测器(波长280nm)对藿香正气合剂进行 HPLC 指纹图谱分析。结果:对20批藿香正气合剂供试品进行检测,建立了该药品的 HPLC 指纹图谱并标示了15个共有指纹峰。各共有峰相对保留时间 RSD 均在1.00%以内。结论:该方法准确、重现性好,为藿香正气合剂的进一步质量标准化研究和控制提供依据。%Objective To establish the HPLC fingerprint of Huoxiang Zhengqi Mixture.Methods The constituents of Huoxiang Zhengqi Mixture were analyzed by HPLC with UV detector (wavelength 280nm)using direct sampling and hesperidin used as the refer-ence substance.Results HPLC fingerprint of Huoxiang Zhengqi Mixture,15 common peaks were established on the basis of system atic methodology after 20 batches of samples were tested Variation in the relative retention time of 15 identified common peaks were within 1.00% range.Conclusion The analytical method for Huoxiang Zhengqi Mixture is precise and reliable.The research would be helpful to offer an effective pattern for quality control of Huoxiang Zhengqi Mixture.

  15. HPLC analysis, isolation and identification of a new degradation product in carvedilol tablets.

    Science.gov (United States)

    Galanopoulou, Olga; Rozou, Stavroula; Antoniadou-Vyza, Ekaterini

    2008-09-10

    Carvedilol (CV) is an antagonist of alpha1 and beta1,beta2 membrane adrenoceptors and also a modulator of cardiac electrophysiological properties. It is widely prescribed for the treatment of cardiovascular diseases. During stability testing of CV solid dosage forms an unknown degradation product referred as UP, exceeded the identification thresholds of ICH Q3B guidelines. The HPLC analysis of the detected unknown product was performed by a newly, developed, specific and validated method, also suitable for the quantitative determination of the known CV impurities (imp B, C, E and F) and the other degradation products. The separation was achieved with an X-terra C18 column, using acetonitrile-phosphate buffer pH 2.5 as mobile phase. The isolation of UP was carried out by semi-preparative chromatography method, followed by deep freezing of the collected fractions until the organic and the aqueous phases were separated. Chromatographic behaviour of CV and UP was compared, in mobile phases of different pH and gave valuable information concerning the dissimilarities of their ionization. UP was further studied by MS and 1H NMR spectrometry, revealing structural similarities with the parent molecule. Finally, the unknown peak of degradation product was attributed to a new compound generated from the interaction of CV molecule and polyvinyl pyrrolidone (PVP) in the presence of water molecules. Moisture and temperature was proved to affect the formation of UP and its concentration in CV tablets. Appropriate modifications of the packaging of CV tablets can be made in order to reduce UP concentration down to the accepted levels, during the tablets' shelf life.

  16. Enantiomeric HPLC resolution and absolute stereochemistry assignment of a new poligamain derivative.

    Science.gov (United States)

    Pistolozzi, M; Royo, V; Pereira, A C; Silva, M L A; Silva, R; Cunha, W R; Vaconcelos, K; Cass, Q B; Martins, C H G; Bastos, J K; Varchi, G; Guerrini, A; Bertucci, C

    2013-03-05

    A new aryltetralin lignan derivative, 1, was obtained by reacting dimethyl succinate and piperonal, furnishing the lactone 4-(3',4'-methylenedioxybenzyl)-4,5-dihydro-2(3H)-furanone, which was reacted once again with piperonal and LDA to give the dibenzylbutirolactone 7-hydroxyhinokinin. The cyclization of 7-hydroxyhinokinin into polygamain occurred in the presence of trifluoroacetic acid. The reduction of the furanic ring of polygamain was done by its reaction with DIBAL in THF, furnishing the diol functionalized lignin derivative 1 as single diastereomer. The enantiomeric fractions of 1 were obtained by preparative enantioselective HPLC. The absolute stereochemistry was assigned by electronic circular dichroism (ECD) and nuclear magnetic resonance (NMR) spectroscopy. An all-trans relative configuration was determined by NMR on the bases of ¹H coupling constants and nuclear Overhauser effect (n.O.e.) experiments. The absolute configuration at C1 was assigned on the basis of the ECD sign at 296 nm by comparison to the ECD spectra of structural analogues with defined stereochemistry. The assignment of the absolute configuration was confirmed by applying the exciton chirality method to the well-defined ECD couplets at 285 and 200 nm allied to the two electronic transitions L(b) and B(b) of the aromatic moieties, respectively. Rac-1 and its enantiomeric isomers were evaluated against important bacteria responsible for dental caries. The best results obtained for the (1R,2S,3S) isomer were against Streptococcus mutans (250 μM), Streptococcus salivarius (250 μM), Streptococcus sobrinus (280 μM) and Streptococcus mitis (280 μM). The (1S,2R,3R) isomer was active only against Streptococcus sanguinis (280 μM). The enantiomeric mixture was less active than the (1R,2S,3S) isomer.

  17. Single sample extraction and HPLC processing for quantification of NAD and NADH levels in Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Sporty, J; Kabir, M M; Turteltaub, K; Ognibene, T; Lin, S; Bench, G

    2008-01-10

    A robust redox extraction protocol for quantitative and reproducible metabolite isolation and recovery has been developed for simultaneous measurement of nicotinamide adenine dinucleotide (NAD) and its reduced form, NADH, from Saccharomyces cerevisiae. Following culture in liquid media, approximately 10{sup 8} yeast cells were harvested by centrifugation and then lysed under non-oxidizing conditions by bead blasting in ice-cold, nitrogen-saturated 50-mM ammonium acetate. To enable protein denaturation, ice cold nitrogen-saturated CH{sub 3}CN + 50-mM ammonium acetate (3:1; v:v) was added to the cell lysates. After sample centrifugation to pellet precipitated proteins, organic solvent removal was performed on supernatants by chloroform extraction. The remaining aqueous phase was dried and resuspended in 50-mM ammonium acetate. NAD and NADH were separated by HPLC and quantified using UV-VIS absorbance detection. Applicability of this procedure for quantifying NAD and NADH levels was evaluated by culturing yeast under normal (2% glucose) and calorie restricted (0.5% glucose) conditions. NAD and NADH contents are similar to previously reported levels in yeast obtained using enzymatic assays performed separately on acid (for NAD) and alkali (for NADH) extracts. Results demonstrate that it is possible to perform a single preparation to reliably and robustly quantitate both NAD and NADH contents in the same sample. Robustness of the protocol suggests it will be (1) applicable to quantification of these metabolites in mammalian and bacterial cell cultures; and (2) amenable to isotope labeling strategies to determine the relative contribution of specific metabolic pathways to total NAD and NADH levels in cell cultures.

  18. A sensitive post-column photochemical derivatization/fluorimetric detection system for HPLC determination of bisphosphonates.

    Science.gov (United States)

    Pérez-Ruiz, Tomás; Martínez-Lozano, Carmen; García-Martínez, María Dolores

    2009-02-27

    A new reversed-phase ion-pair high-performance liquid chromatographic (HPLC) method has been developed for the determination of the following bisphosphonic acids: alendronic acid (ALEN), etidronic acid (ETID), ibandronic acid (IBAN) and risedronic acid (RISE). Separation was achieved on a C(18) column using a mixture of 50 mmol L(-1) borate buffer pH 9.0 containing 0.25 mmol L(-1) tetrabutylammonium chloride and 0.5 mmol L(-1) EDTA and acetonitrile (97:3) as the mobile phase. The sensitive detection of the above bisphosphonic acids was based on their oxidation to orthophosphate by the on-line peroxydisulfate-assisted photolysis followed by post-column reaction with molybdate to yield phosphomolybdate. This subsequently reacted with thiamine to generate thiochrome and, finally, the fluorescence of thiochrome was measured at 440 nm with excitation at 375 nm. The developed method is precise with a mean relative standard deviation of 1.3%, sensitive (with a detection limit at the nmol L(-1) level), accurate, specific, rapid (analysis time approximately 13 min) and inexpensive because to the low cost of the reagents. The assay was applied to the analysis of the four bisphosphonic acids in commercial dosage formulations, in which the excipients did not interfere with the determination. The method was also applied to the determination of etidronate, risedronate and ibandronate in human urine. Sample preparation involves precipitation of the analytes from urine along with endogenous phosphates such as calcium salts by addition of calcium chloride at alkaline pH and dissolution of the precipitate in 0.05 mol L(-1) ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid.

  19. Automated precolumn derivatization procedures in HPLC for biomedical and clinical applications

    NARCIS (Netherlands)

    Wolf, Johannes Hendrik

    1992-01-01

    This thesis describes three automated precolumn derivatization procedures for the analysis of carboxylic group-containing compounds. After derivatization with a suitable label, the derivatives are separated on reversed-phashed HPLC and detected by fluorescence. ... Zie: Summary

  20. Multielemental speciation analysis by advanced hyphenated technique - HPLC/ICP-MS: A review.

    Science.gov (United States)

    Marcinkowska, Monika; Barałkiewicz, Danuta

    2016-12-01

    Speciation analysis has become an invaluable tool in human health risk assessment, environmental monitoring or food quality control. Another step is to develop reliable multielemental speciation methodologies, to reduce costs, waste and time needed for the analysis. Separation and detection of species of several elements in a single analytical run can be accomplished by high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Our review assembles articles concerning multielemental speciation determination of: As, Se, Cr, Sb, I, Br, Pb, Hg, V, Mo, Te, Tl, Cd and W in environmental, biological, food and clinical samples analyzed with HPLC/ICP-MS. It addresses the procedures in terms of following issues: sample collection and pretreatment, selection of optimal conditions for elements species separation by HPLC and determination using ICP-MS as well as metrological approach. The presented work is the first review article concerning multielemental speciation analysis by advanced hyphenated technique HPLC/ICP-MS.

  1. Method for Vanadium Speciation in Aqueous Samples by HPLC-ICP ...

    African Journals Online (AJOL)

    NJD

    Anion exchange, vanadium speciation, EDTA, HPLC, ICP-OES. 1. Introduction ... The stock solutions of 200 mmol L–1 EDTA and 500 mmol L–1 sodium carbonate ... Merck, Darmstadt, Germany), and 0.1148 g of ammonium metavanadate ...

  2. Spectroscopic characterization and quantitative determination of atorvastatin calcium impurities by novel HPLC method

    Science.gov (United States)

    Gupta, Lokesh Kumar

    2012-11-01

    Seven process related impurities were identified by LC-MS in the atorvastatin calcium drug substance. These impurities were identified by LC-MS. The structure of impurities was confirmed by modern spectroscopic techniques like 1H NMR and IR and physicochemical studies conducted by using synthesized authentic reference compounds. The synthesized reference samples of the impurity compounds were used for the quantitative HPLC determination. These impurities were detected by newly developed gradient, reverse phase high performance liquid chromatographic (HPLC) method. The system suitability of HPLC analysis established the validity of the separation. The analytical method was validated according to International Conference of Harmonization (ICH) with respect to specificity, precision, accuracy, linearity, robustness and stability of analytical solutions to demonstrate the power of newly developed HPLC method.

  3. Antioxidant, antiinflammatory activities and HPLC analysis of South African Salvia species

    CSIR Research Space (South Africa)

    Kamatou, GGP

    2010-03-01

    Full Text Available -performance liquid chromatography (HPLC) was used to identify various compounds in the extracts. Betulafolientriol oxide and rosmarinic acid were detected in all the species investigated, and rosmarinic acid, carnosic acid, carnosol and oleanolic acid/ursolic acid...

  4. Automated precolumn derivatization procedures in HPLC for biomedical and clinical applications

    NARCIS (Netherlands)

    Wolf, Johannes Hendrik

    1992-01-01

    This thesis describes three automated precolumn derivatization procedures for the analysis of carboxylic group-containing compounds. After derivatization with a suitable label, the derivatives are separated on reversed-phashed HPLC and detected by fluorescence. ... Zie: Summary

  5. Fast HPLC for quality control of Harpagophytum procumbens by using a monolithic silica column: method transfer from conventional particle-based silica column.

    Science.gov (United States)

    Schmidt, Alexander H

    2005-05-06

    The applicability of a monolithic C18-bonded silica column for the rapid HPLC separation of ingredients in medicinal plants and their phytopharmaceutical preparations has been evaluated in the author's laboratory. In this presentation, an existing method for the determination of the iridoid glycoside harpagoside in Harpagophytum procumbens (Devil's Claw) was successfully transferred from a conventional particle-based C18 silica column to a monolithic silica column. The very high porosity of the stationary phase allows chromatography with a much lower backpressure than on conventional columns. Therefore, the flow rate could be easily increased from 0.8 mL/min (particle-based column) to 5 mL/min (monolithic column) and the run-time reduced from 30 to 5 min (that is a reduction about 85% !), without losing any chromatographic resolution of the compound of interest. The amount of harpagoside was measured with the original method on a conventional particle-based silica column and on the adapted method on a monolithic silica column. The statistical mean t-test showed no significant differences of the variances and the means indicating that the fast HPLC method is an acceptable alternative. The shorter analysis time makes the method very valuable for commercial quality control of Harpagophytum extracts and its pharmaceutical preparations.

  6. HPLC detection of plasma concentrations of diclofenac in human volunteers administered with povidone-ethylcellulose-based experimental transdermal matrix-type patches.

    Science.gov (United States)

    Mukherjee, B; Mahapatra, S; Das, S; Roy, G; Dey, S

    2006-06-01

    By developing a high-performance liquid chromatography (HPLC) method, we estimated the blood concentrations of diclofenac in human volunteers administered with the transdermal patches prepared with povidone-ethylcellulose and oral diclofenac tablets. Drug-excipient interaction studies were done using the FTIR technique. The external morphology of the prepared patch before and after application to human skin was analyzed with scanning electron microscopy. FTIR studies revealed that there was no predominant interaction between the drug and polymers. In vivo studies revealed that the average concentrations of drug in plasma were 376, 1562, 2953, 2902, 2864, and 2948 ng/ml after 2, 4, 8, 24, 30, and 48 h from patches each containing 50 mg of diclofenac diethylamine, respectively, and the mean concentrations of drug in plasma after the oral administration of marketed tablet containing 50 mg diclofenac sodium were 383.7, 2569, 3693.5, 162.5, and 55.3 ng/ml at 2, 4, 8, 24, and 30 h after oral administration. Values of Cmax were 3693.5 after oral administration and 2953.8 ng/ml in the case of transdermal application. From this study, we have achieved the sustained blood level of diclofenac from the experimental patches along with an analytical method based on HPLC to determine the diclofenac blood level. Copyright 2006 Prous Science.

  7. Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction

    Institute of Scientific and Technical Information of China (English)

    LI Cun-man; XIAO Yuan-sheng; XUE Xing-ya; FENG Jia-tao; ZHANG Xiu-li; LIANG Xin-miao

    2011-01-01

    An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was per formed with a C1s packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully iso lated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleo tide compound were simultaneously obtained, each with a purity of >91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, ID and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

  8. Application of HPLC-Charged Aerosol Detection%HPLC-电雾式检测器的应用

    Institute of Scientific and Technical Information of China (English)

    刘路; 高旋; 杨永健

    2012-01-01

    电雾式检测器(CAD)是一种新型通用型液相色谱检测器,具有较宽的动态监测范围、较高的灵敏度和重复性、不依赖于化学结构的信号响应一致性、应用广泛和操作简捷等优点,应用于中性、酸性、碱性及两性物质等,特别是无紫外吸收、非挥发性或半挥发性物质的检测.本文简要介绍了CAD检测器的工作原理及其应用.%Charged aerosol detection (CAD) is a novel generic HPLC detector. CAD system has some advantages such as broad dynamic response range, good precision and sensitivity, response independent of chemical properties, widespread application and simple and reliable operation. CAD has been applied for the analysis of neutral, acidic, basic and zwitterionic compounds without volatility and ultraviolet activity. This review introduces its operation principle and selected applications.

  9. Off-line coupling of new generation centrifugal partition chromatography device with preparative high pressure liquid chromatography-mass spectrometry triggering fraction collection applied to the recovery of secoiridoid glycosides from Centaurium erythraea Rafn. (Gentianaceae).

    Science.gov (United States)

    Mandova, Tsvetelina; Audo, Grégoire; Michel, Sylvie; Grougnet, Raphaël

    2017-09-01

    A purification sequence including a Gilson CPC 250 PRO device coupled to PrepHPLC hyphenated with a MS triggering fraction collector was applied to isolate secoiridoid glycosides from a complex methanolic extract of Centaurium erythraea. This species is widely used for ethnomedicinal purposes around the Mediterranean Sea. The solvent system ethyle acetate/ethanol/water 7.5/3/5 was determined using shake-flask method targeting swertiamarin, the major secoiridoid of the extract. Optimization of CPC experimental parameters enabled the injection of 4g of extract with a flow rate of 40mL/min at 3000rpm to provide a secoiridoid glycosides enriched fraction. 130mg of this latter was submitted to a second step of purification by preparative HPLC (gradient water/formic acid (19:1) (A) and methanol (B) as follows: 0min, 85% A; 8min, 60% A; 12min, 55% A; 35min, 55% A; 40min, 10% A; 50min, 10% A; 52min, 85% A; 55min, 85% A) to give swertiamarin (36mg, yield 27.7%, purity 98.2%). Other secoiridoid glycosides (sweroside, gentiopicroside, secologanol, secoxyloganin) were also isolated in minor amounts. As these monoterpene derivatives are responsible for several biological activities, their quick recovery with high yield and purity may serve as a model for further scale-up and industrial development. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. [Glycolytic activity of enzyme preparation from the red king crab (Paralithodes camtschaticus) hepatopancreas].

    Science.gov (United States)

    Rysakova, K S; Novikov, V Iu; Mukhin, V A; Serafimchik, E M

    2008-01-01

    Enzyme preparation exhibiting glycolytic activity yielding chitooligosaccharides along with N-acetyl-D-glucosamine was obtained from the red king crab (Paralithodes camtschaticus) hepatopancreas. The results of the analysis confirmed the presence of endo- and exochitinase activities in the preparation. HPLC showed that the hydrolysis products of chitin and chitosan did not contain D(+)-glucosamine, which is indicative of the absence of deacetylase and, apparently, exochitosanase activities. A comparison of the dependence of the enzyme preparation activity on temperature and pH of the incubation medium suggests that chitinase and protease activities are exhibited by different enzymes.

  11. RISA-HPLC analysis of lung bacterial colonizers of cystic fibrosis children.

    Science.gov (United States)

    Nazaret, S; Assade, F; Brothier, E; Freydière, A-M; Bellon, G; Cournoyer, B

    2009-01-01

    Microbiological analysis of sputum samples, from children affected by cystic fibrosis (CF) and showing signs of acute or chronic infections, is routinely performed by culture-dependent approaches involving selective media and biochemical tests. These identification schemes are time-consuming, and may lead to false negative results. The aim of this work was to evaluate the efficacy of a Ribosomal Intergenic Spacer Analysis (RISA) coupled to high performance liquid chromatography (HPLC) for the detection and monitoring of CF lung microbial colonizers including Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa, the Burkholderia cepacia complex, Stenotrophomonas maltophilia, and Achromobacter xylosoxidans. These RISA-HPLC analyses were performed over a 10-months period on infants (below 18 months) and children that were or were not yet known to be colonised by P. aeruginosa. The RISA-HPLC profiles were found specific of the patients' microbial communities. A specific P. aeruginosa RISA-HPLC peak corresponding to 550 bp PCR products was recorded, and used to investigate P. aeruginosa persistence through time and after various therapeutic treatments. The RISA-HPLC profiles showed the CF children to be colonized by few bacterial species, and sometimes revealed peaks corresponding to bacterial species that were not detected by the selective plating approaches. Significant RISA-HPLC infra-specific variations were observed for most bacterial colonizers of CF lungs except P. aeruginosa. These species could yield as much as 5 distinct RISA-HPLC peaks, with some of these profiles being strain-specific. RISA-HPLC shows a great potential for revealing colonization by novel emerging pathogens, and for evaluating the efficacy of therapeutic treatments on the global bacterial community of CF lungs.

  12. Glucose, cellobiose, lactose and raffinose used as chiral stationary phases in HPLC

    Institute of Scientific and Technical Information of China (English)

    Jian Yu Wang; Feng Zhao; Mei Zhang; Ya Peng; Li Ming Yuan

    2008-01-01

    This paper presents the enantioseparation using glucose,cellobiose,lactose and raffinose as chiral selector bonded to silica gel via an arm in HPLC.Surprisingly,they also possess high enantioseparation selectivity,may be used in normal-phase and reversedphase mode.and there is a big chiral discriminating complementary.This work indicates that oligosacchafides could soon become very attractive as a new class of chiral stationary phase for HPLC.

  13. DETERMINATION OF PROTEINS FROM BUFFALO MILK USING HIGH PERFORMANCE LIQUID CROMATOGRAPHY RP-HPLC

    OpenAIRE

    AURELIA PECE; COROIAN C.; BIANCA GHIRILĂ; G. MURESAN; VIOARA MIRESAN

    2013-01-01

    In the hereby paper, we have undertaken a study on buffalo milk proteins, employing high performance liquid chromatography (HPLC). This RP-HPLC technique is commonly employed in the separation and assessment of caseins K, and in the fresh, as well as processed milk. These methods are also successfully applied in the authenticity and origin assessment of certain cheese products and the qualitative analysis of milk in bubalines, ovines, caprines and bovines (Ferreira si Cacote, 2003; Veloso si...

  14. [The bioequivalence of two oral propafenone preparations].

    Science.gov (United States)

    Koytchev, R; Alken, R G; Mayer, O; Böhm, R; Ellrich, A; Waldner-Kölblin, R G

    1995-05-01

    The bioequivalence of two oral racemic propafenone (CAS 54063-53-5) preparations was tested in an open, randomised, crossover trial with administration of single doses of 300 mg on two different occasions with a washout period of 7 days. 24 healthy, male volunteers, all proved to be rapid hydroxylators of debrisoquine, were enrolled in the trial. The concentrations of R(+)-, S(-)-propafenone and 5-hydroxypropafenone (5-OH-propafenone) were measured up to 12 h after administration by means of a sensitive and specific HPLC method that allowed the simultaneous quantification of all three substances in plasma. The results of 23 volunteers were evaluated pharmacokinetically. Main target parameters were AUC0-infinity and Cmax of both enantiomers of propafenone. Secondary target parameters were AUC0-infinity and Cmax of 5-OH-propafenone as well as tmax for R(+)- and S(-)-propafenone. The 90% confidence intervals for AUC0-infinity for R(+)-, S(-)-, and 5-OH-propafenone were 0.85-1.07, 0.83-1.10 and 0.84-1.05, respectively. The confidence intervals for Cmax were 0.81-1.12, 0.82-1.17 and 0.87-1.09 for R-, S-, and 5-OH-propafenone, respectively. The concentration maxima of both enantiomers were registered on average 15 min earlier after administration of the test preparation. This difference is of no clinical relevance. Both preparations are bioequivalent according to the criteria of the Committee for Proprietary Medicinal Products (CPMP).

  15. A New HPLC-ELSD Method for Simultaneous Determination of N-Acetylglucosamine and N-Acetylgalactosamine in Dairy Foods

    Directory of Open Access Journals (Sweden)

    Ho Jin Kim

    2015-01-01

    Full Text Available A rapid high performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD, using a carbohydrate column, was developed for simultaneous determination of N-acetylglucosamine (GlcNAc and N-acetylgalactosamine (GalNAc in dairy foods. Sample preparation was performed by precipitation using acetonitrile. The limits of detection were 2.097 mg/L for GlcNAc and 3.247 mg/L for GalNAc. The limits of quantification were 6.043 mg/L for GlcNAc and 9.125 mg/L for GalNAc. Accuracy ranged from 96.4 to 105.7% for GlcNAc and from 97.1 to 104.1% for GalNAc. The precision of the method was <1.7% for GlcNAc and <2.2% for GalNAc. The mean recovery of the method was measured by spiking samples with 30.0–120.0 mg/L GlcNAc or 12.5–50.0 mg/L GalNAc and was found to be 95.1–105.5% for GlcNAc and 99.5–105.9% for GalNAc. The stability test results of standard solutions stored at 4, 20, and 40°C were 96.2–104.7% for GlcNAc and 98.0–106.5% for GalNAc. This study determined GlcNAc and GalNAc in dairy foods using HPLC-ELSD method. This rapid, simultaneous quantitation method might be useful as a mean of convenient quality control of dairy foods.

  16. Simultaneous determination of -2 wtexm-2 -O-glucostde, vitexm-2 -O-rhamnoslde, turin, vitexin and hyperoside by HPLC

    Institute of Scientific and Technical Information of China (English)

    Chang-He Wang; Yu-Xuan Wang; Hai-Jing Liu

    2011-01-01

    A simple, precise, and rapid high-performance liquid chromatographic method was developed and validated for the simultaneous determination of vitexin-2"-O-glucoside, vitexin-2"-O-rhamnoside, rutin, vitexin, and hyperoside. The HPLC separation was performed using a Shim-pack VP-ODS C18 column (250 mm ~ 4.6 mm i.d., 5 ~tm) with the isocratic mobile phase consisting of tetrahydrofuran/ acetonitrile/0.05% phosphoric acid solution (20:3:77, v/v/v), and the flow rate was set at 1.0 mL/min. UV detection was carried out at a wavelength of 360 nrn and the whole analysis took 25 min. The method was linear in the range of 4.12-206.00 μg/mL for vitexin-2"-O-glucoside, 4.05-202.50 μg/mL for vitexin-2"-O- rhanmoside, 1.64-82.00 pμg/mL for rutin, 1.74-87.00 gg/mL for vitexin, and 1.41-70.60 p.g/mL for hyperoside with the correlation coefficient for each analyte more than 0.998. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.6 and 2 ng for vitexin-2"-O-glucoside, 0.6 and 2 ng for vitexin-2"-O-rhamnoside, 0.3 and 1 ng for rutin, 1 and 3 ng for vitexin, and 0.5 and 2 ng for hyperoside, respectively. Intra- and inter-day precision and accuracy (RSD) were less than 3%. The developed HPLC method was successfully applied to the analysis of five flavonoids in hawthorn leaves, hawthorn fruits, and the preparations containing hawthorn leaves or fruits.

  17. Nucleoside Fingerprinting of Cultured Cordyceps militaris Strains Using HPLC%人工培养蛹虫草核苷类HPLC指纹图谱的建立

    Institute of Scientific and Technical Information of China (English)

    简伟明; 李洁仪; 梁慧敏

    2014-01-01

    A stable,precise and reproducible HPLC-based method for determining the nucleoside fingerprints of cultured Cordyceps militaris strains has been developed.Extracts were prepared by suspending 0.5 g powdered fruit body in 20 mL 20% methanol and exposing to ultrasound (40 kHz)for 1 h at 30 ℃.After filtration,samples were subjected to HPLC for nucleosides analysis. HPLC spectra obtained from ten cultured C.militaris fruit body samples were subjected to professional analytical software recommended by the Pharmacopoeia Commission of People’s Republic of China (China version 2004A)to create a standard HPLC fingerprint for cultured C.militaris consisting of ten common peaks.Cordycepin and adenosine peaks in the fingerprint were confirmed by comparing the retention times with those of cordycepin and adenosine standards.Similarity coefficients between C.militaris samples and the fingerprint standard were all higher than 0 .9 .%建立了蛹虫草(Cordyceps militaris)核苷类高效液相色谱(HPLC)指纹图谱的分析方法,采集10批不同产地人工培养蛹虫草HPLC图谱,运用“中药色谱指纹图谱相似度评价系统2004A版”软件建立人工蛹虫草标准图谱并以该模式为参照,计算10批不同产地蛹虫草之间的相似度。结果表明:方法的稳定性、精密度、重现性符合方法学要求;建立的核苷类 HPLC指纹图谱共得到10个共有峰,并对确认了虫草素和腺苷峰这两个特征峰,各样品图谱与标准指纹图谱的相似度均在0.9以上。

  18. Physical and chemical properties and stability of sodium cefazolin in buffered eye drops determined with HPLC method.

    Science.gov (United States)

    Kodym, Anna; Bilski, Piotr; Domańska, Agata; Hełminiak, Łukasz; Jabłońska, Maria; Jachymska, Anna

    2012-01-01

    The aim of the studies was to analyze the stability of 1% and 5% eye drops containing sodium cefazolin, prepared in citrate buffer of pH 6.11-6.27, which were stored at the temperature of 4 degrees C and 20 degrees C with light protection. The drops were prepared under aseptic conditions by dissolving sodium cefazolin (Biofazolin, IBA Bioton), dry injection form of the drug, in citrate buffer. The viscosity of the drops was increased using polyvinyl alcohol. The drops were preserved with phenylmercuric borate of 0.001% concentration mixed with beta-phenylethyl alcohol of 0.4% concentration in the drops. The concentration of cefazolin was determined at every three days using HPLC method. Besides, the measurements of pH, osmotic pressure and viscosity were performed as well as the organoleptic analysis of the drops (clarity, color, odor). The concentration of cefazolin in 1% drops after the 30-day-storage at the temperature of 4 degrees C, depending on their composition, decreased in the range of 2.17-6.02%. In 5% drops the decrease in cefazolin concentration was similar, i.e., after 30-day-storage at the temperature of 4 degrees C it was 1.62-6.76%. In 1% and 5% drops stored at the temperature of 20 degrees C the stability of the drops determined as the 10% degradation time of cefazolin was in the range of 9-15 days.

  19. Cluster analysis of historical and modern hard red spring wheat cultivars based on parentage and HPLC analysis of gluten forming proteins

    Science.gov (United States)

    In this study, 30 hard red spring (HRS) wheat cultivars released between 1910 and 2013 were analyzed to determine how they cluster in terms of parentage and protein data, analyzed by reverse-phase HPLC (RP-HPLC) of gliadins, and size-exclusion HPLC (SE-HPLC) of unreduced proteins. Dwarfing genes in...

  20. Identifying Phytoplankton Classes In California Reservoirs Using HPLC Pigment Analysis

    Science.gov (United States)

    Siddiqui, S.; Peacock, M. B.; Kudela, R. M.; Negrey, K.

    2014-12-01

    Few bodies of water are routinely monitored for phytoplankton composition due to monetary and time constraints, especially the less accessible bodies of water in central and southern California. These lakes and estuaries are important for economic reasons such as tourism and fishing. This project investigated the composition of phytoplankton present using pigment analysis to identify dominant phytoplankton groups. A total of 28 different sites with a wide range of salinity (0 - 60) in central and southern California were examined. These included 13 different bodies of water in central California: 6 in the Sierras, 7 in the San Francisco Bay Estuary, and 15 from southern California. The samples were analyzed using high-performance liquid-chromatography (HPLC) to quantify the pigments present (using retention time and the spectral thumbprint). Diagnostic pigments were used to indicate the phytoplankton class composition, focusing on diatoms, dinoflagellates, cryptophytes, and cyanobacteria - all key phytoplankton groups indicative of the health of the sampled reservoir. Our results indicated that cyanobacteria dominated four of the seven bodies of central California water (Mono Lake, Bridgeport Reservoir, Steamboat Slough, and Pinto Lake); cryptophytes and nannoflagellates dominated two of the central California bodies of water (Mare Island Strait and Topaz Lake); and diatoms and dinoflagellates dominated one central California body of water, Oakland Inner Harbor, comprising more than 70% of the phytoplankton present. We expect the bodies of water from Southern California to be as disparate. Though this data is only a snapshot, it has significant implications in comparing different ecosystems across California, and it has the potential to provide valuable insight into the composition of phytoplankton communities.