WorldWideScience

Sample records for high-performance liquid chromatography-based

  1. Development of a high performance liquid chromatography method ...

    African Journals Online (AJOL)

    Development of a high performance liquid chromatography method for simultaneous ... Purpose: To develop and validate a new low-cost high performance liquid chromatography (HPLC) method for ..... Several papers have reported the use of ...

  2. [High-performance liquid-liquid chromatography in beverage analysis].

    Science.gov (United States)

    Bricout, J; Koziet, Y; de Carpentrie, B

    1978-01-01

    Liquid liquid chromatography was performed with columns packed with stationary phases chemically bonded to silica microparticules. These columns show a high efficiency and are used very easily. Flavouring compounds like aromatic aldehydes which have a low volatility were analyzed in brandy using a polar phase alkylnitrile. Sapid substances like amarogentin in Gentiana lutea or glyryrrhizin in Glycyrrhiza glabra were determined by reversed phase chromatography. Finally ionizable substances like synthetic dyes can be analyzed by paired ion chromatography witha non polar stationary phase.

  3. High performance liquid chromatography in pharmaceutical analyses

    Directory of Open Access Journals (Sweden)

    Branko Nikolin

    2004-05-01

    Full Text Available In testing the pre-sale procedure the marketing of drugs and their control in the last ten years, high performance liquid chromatographyreplaced numerous spectroscopic methods and gas chromatography in the quantitative and qualitative analysis. In the first period of HPLC application it was thought that it would become a complementary method of gas chromatography, however, today it has nearly completely replaced gas chromatography in pharmaceutical analysis. The application of the liquid mobile phase with the possibility of transformation of mobilized polarity during chromatography and all other modifications of mobile phase depending upon the characteristics of substance which are being tested, is a great advantage in the process of separation in comparison to other methods. The greater choice of stationary phase is the next factor which enables realization of good separation. The separation line is connected to specific and sensitive detector systems, spectrafluorimeter, diode detector, electrochemical detector as other hyphernated systems HPLC-MS and HPLC-NMR, are the basic elements on which is based such wide and effective application of the HPLC method. The purpose high performance liquid chromatography(HPLC analysis of any drugs is to confirm the identity of a drug and provide quantitative results and also to monitor the progress of the therapy of a disease.1 Measuring presented on the Fig. 1. is chromatogram obtained for the plasma of depressed patients 12 h before oral administration of dexamethasone. It may also be used to further our understanding of the normal and disease process in the human body trough biomedical and therapeutically research during investigation before of the drugs registration. The analyses of drugs and metabolites in biological fluids, particularly plasma, serum or urine is one of the most demanding but one of the most common uses of high performance of liquid chromatography. Blood, plasma or

  4. Comparison of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography for the separation of synthetic cathinones.

    Science.gov (United States)

    Carnes, Stephanie; O'Brien, Stacey; Szewczak, Angelica; Tremeau-Cayel, Lauriane; Rowe, Walter F; McCord, Bruce; Lurie, Ira S

    2017-09-01

    A comparison of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography for the separation of synthetic cathinones has been conducted. Nine different mixtures of bath salts were analyzed in this study. The three different chromatographic techniques were examined using a general set of controlled synthetic cathinones as well as a variety of other synthetic cathinones that exist as positional isomers. Overall 35 different synthetic cathinones were analyzed. A variety of column types and chromatographic modes were examined for developing each separation. For the ultra high performance supercritical fluid chromatography separations, analyses were performed using a series of Torus and Trefoil columns with either ammonium formate or ammonium hydroxide as additives, and methanol, ethanol or isopropanol organic solvents as modifiers. Ultra high performance liquid chromatographic separations were performed in both reversed phase and hydrophilic interaction chromatographic modes using SPP C18 and SPP HILIC columns. Gas chromatography separations were performed using an Elite-5MS capillary column. The orthogonality of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography was examined using principal component analysis. For the best overall separation of synthetic cathinones, the use of ultra high performance supercritical fluid chromatography in combination with gas chromatography is recommended. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. [Analysis of microalbuminuria with immunonephelometry and high performance liquid chromatography. Evaluation of new criteria].

    Science.gov (United States)

    Markó, Lajos; Molnár, Gergo Attila; Wagner, Zoltán; Koszegi, Tamás; Matus, Zoltán; Mohás, Márton; Kuzma, Mónika; Szijártó, István András; Wittmann, István

    2008-01-13

    Hypertension as well as type 2 diabetes mellitus is a major factor in population mortality. Both diseases damage the endothelium, the early sign of which is microalbuminuria, which can be screened by dipstick and can be diagnosed by using immuno-based and high performance liquid chromatography methods. Using high performance liquid chromatography, the non-immunoreactive albumin can be detected as well. The authors aimed at the examination of albuminuria in the case of immunonephelometrically negative patients with high performance liquid chromatography, in diabetic and hypertensive and non-diabetic hypertensive populations. The authors also wanted to compare the present (albumin-creatinine ratio: male: > or =2.5 mg/mmol, female: > or =3.5 mg/mmol) and a new criteria of the Heart Outcomes Prevention Evaluation study (patients without diabetes: immunological method, > or =0.7 mg/mmol; high performance liquid chromatography, > or =3.1 mg/mmol; individuals with diabetes: immunological method, > or =1.4 mg/mmol; high performance liquid chromatography, > or =5.2 mg/mmol) of microalbuminuria. Examination of fresh urines of 469 microalbuminuria negative patients by dipstick were performed by immunonephelometry. Patients, who were microalbuminuria negative by immunonephelometry as well, were further analyzed by high performance liquid chromatography using the Accumintrade mark Kit, based on size-exclusion chromatography. Three times higher albuminuria were found with high performance liquid chromatography than with immunonephelometry. The intraindividual coefficient of variation did not differ in the two methods (37 +/- 31% vs. 40 +/- 31%, p = 0.869; immunonephelometry vs. high performance liquid chromatography; mean +/- standard deviation). Using the present criteria for microalbuminuria, 43% of immunonephelometrically negative patients proved to be microalbuminuric by high performance liquid chromatography. Using the new criteria of the Heart Outcomes Prevention

  6. Gradient High Performance Liquid Chromatography Method ...

    African Journals Online (AJOL)

    Purpose: To develop a gradient high performance liquid chromatography (HPLC) method for the simultaneous determination of phenylephrine (PHE) and ibuprofen (IBU) in solid ..... nimesulide, phenylephrine. Hydrochloride, chlorpheniramine maleate and caffeine anhydrous in pharmaceutical dosage form. Acta Pol.

  7. High-Performance Liquid Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Vestal, Marvin L.

    1984-01-01

    Reviews techniques for online coupling of high-performance liquid chromatography with mass spectrometry, emphasizing those suitable for application to nonvolatile samples. Also summarizes the present status, strengths, and weaknesses of various techniques and discusses potential applications of recently developed techniques for combined liquid…

  8. High-performance liquid chromatography of oligoguanylates at high pH

    Science.gov (United States)

    Stribling, R.; Deamer, D. (Principal Investigator)

    1991-01-01

    Because of the stable self-structures formed by oligomers of guanosine, standard high-performance liquid chromatography techniques for oligonucleotide fractionation are not applicable. Previously, oligoguanylate separations have been carried out at pH 12 using RPC-5 as the packing material. While RPC-5 provides excellent separations, there are several limitations, including the lack of a commercially available source. This report describes a new anion-exchange high-performance liquid chromatography method using HEMA-IEC BIO Q, which successfully separates different forms of the guanosine monomer as well as longer oligoguanylates. The reproducibility and stability at high pH suggests a versatile role for this material.

  9. Radioactivity monitor for high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Reeve, D.R.; Crozier, A.

    1977-01-01

    The coupling of a homogeneous radioactivity monitor to a liquid chromatograph involves compromises between the sensitivity of the monitor and the resolution and speed of analysis of the chromatograph. The theoretical relationships between these parameters are considered and expressions derived which make it possible to calculate suitable monitor operating conditions for most types of high-performance liquid chromatography

  10. Microcystin Detection Characteristics of Fluorescence Immunochromatography and High Performance Liquid Chromatography

    International Nuclear Information System (INIS)

    Pyo, Dong Jin; Park, Geun Young; Choi, Jong Chon; Oh, Chang Suk

    2005-01-01

    Different detection characteristics of fluorescence immunochromatography method and high performance liquid chromatography (HPLC) method for the analysis of cyanobacterial toxins were studied. In particular, low and high limits of detection, detection time and reproducibility and detectable microcystin species were compared when fluorescence immunochromatography method and high performance liquid chromatography method were applied for the detection of microcystin (MC), a cyclic peptide toxin of the freshwater cyanobacterium Microcystis aeruginosa. A Fluorescence immunochromatography assay system has the unique advantages of short detection time and low detection limit, and high performance liquid chromatography detection method has the strong advantage of individual quantifications of several species of microcystins

  11. Pressurized planar electrochromatography, high-performance thin-layer chromatography and high-performance liquid chromatography--comparison of performance.

    Science.gov (United States)

    Płocharz, Paweł; Klimek-Turek, Anna; Dzido, Tadeusz H

    2010-07-16

    Kinetic performance, measured by plate height, of High-Performance Thin-Layer Chromatography (HPTLC), High-Performance Liquid Chromatography (HPLC) and Pressurized Planar Electrochromatography (PPEC) was compared for the systems with adsorbent of the HPTLC RP18W plate from Merck as the stationary phase and the mobile phase composed of acetonitrile and buffer solution. The HPLC column was packed with the adsorbent, which was scrapped from the chromatographic plate mentioned. An additional HPLC column was also packed with adsorbent of 5 microm particle diameter, C18 type silica based (LiChrosorb RP-18 from Merck). The dependence of plate height of both HPLC and PPEC separating systems on flow velocity of the mobile phase and on migration distance of the mobile phase in TLC system was presented applying test solute (prednisolone succinate). The highest performance, amongst systems investigated, was obtained for the PPEC system. The separation efficiency of the systems investigated in the paper was additionally confirmed by the separation of test component mixture composed of six hormones. 2010 Elsevier B.V. All rights reserved.

  12. Microchip-based monolithic column for high performance liquid chromatography

    Data.gov (United States)

    National Aeronautics and Space Administration — We have developed microchip based monolithic columns that can be used for liquid chromatography of small organic molecules, as well as, macromolecules such as...

  13. Combined high-performance liquid chromatography/32P-postlabeling assay of N7-methyldeoxyguanosine

    International Nuclear Information System (INIS)

    Shields, P.G.; Povey, A.C.; Wilson, V.L.; Weston, A.; Harris, C.C.

    1990-01-01

    A highly sensitive and specific assay for the detection of N7-methyl-2'-deoxyguanosine (N7methyldG) has been developed by combining high-performance liquid chromatography, 32 P-postlabeling, and nucleotide chromatography. Separation of normal nucleotides and adducts by high-performance liquid chromatography and then combining a portion of 2'-deoxyguanosine to the N7methyldG allows for quantitation using an internal standard. The directly determined molar ratio is not subject to errors in digestion, variable ATP-specific activity, or assumptions in relative adduct-labeling efficiency. The detection limit was one N7methyldG adduct in 10(7) unmodified 2'-deoxyguanosine bases. N7methyldG adducts have been detected in 5 human lung samples in which O6-methyl-2'-deoxyguanosine adducts had been previously determined. The mean ratio of N7methyldG to O6-methyl-2'-deoxyguanosine was determined to be approximately 10. The current assay complements the high-performance liquid chromatography/ 32 P-postlabeling assay for O6-methyl-2'-deoxyguanosine and increases the detection sensitivity of DNA methylated by exogenous alkylating agents

  14. Ultra-high Performance Liquid Chromatography in Steroid Analysis

    OpenAIRE

    Salonen, Fanny

    2017-01-01

    The latest version of liquid chromatography is ultra-high performance (or pressure) chromatography (UHPLC). In the technique, short and narrow-bore columns with particle sizes below 3 µm are used. The extremely high pressure used results in very short analysis times, excellent separation, and good resolution. This makes UHPLC a good choice for steroidal analysis. Steroids are a highly interesting area of study; they can be recognized as biomarkers for several diseases and are a relevant topic...

  15. Validated High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    Purpose: To develop a simple, rapid and sensitive high performance liquid chromatography (HPLC) method for the determination of cefadroxil monohydrate in human plasma. Methods: Schimadzu HPLC with LC solution software was used with Waters Spherisorb, C18 (5 μm, 150mm × 4.5mm) column. The mobile phase ...

  16. Highly sensitive reversed-phase high-performance liquid chromatography assay for the detection of Tamm-Horsfall protein in human urine.

    Science.gov (United States)

    Akimoto, Masaru; Hokazono, Eisaku; Ota, Eri; Tateishi, Takiko; Kayamori, Yuzo

    2016-01-01

    Tamm-Horsfall protein (also known as uromodulin) is the most abundant urinary protein in healthy individuals. Since initially characterized by Tamm and Horsfall, the amount of urinary excretion and structural mutations of Tamm-Horsfall protein is associated with kidney diseases. However, currently available assays for Tamm-Horsfall protein, which are mainly enzyme-linked immunosorbent assay-based, suffer from poor reproducibility and might give false negative results. We developed a novel, quantitative assay for Tamm-Horsfall protein using reversed-phase high-performance liquid chromatography. A precipitation pretreatment avoided urine matrix interference and excessive sample dilution. High-performance liquid chromatography optimization based on polarity allowed excellent separation of Tamm-Horsfall protein from other major urine components. Our method exhibited high precision (based on the relative standard deviations of intraday [≤2.77%] and interday [≤5.35%] repetitions). The Tamm-Horsfall protein recovery rate was 100.0-104.2%. The mean Tamm-Horsfall protein concentration in 25 healthy individuals was 31.6 ± 18.8 mg/g creatinine. There was a strong correlation between data obtained by high-performance liquid chromatography and enzyme-linked immunosorbent assay (r = 0.906), but enzyme-linked immunosorbent assay values tended to be lower than high-performance liquid chromatography values at low Tamm-Horsfall protein concentrations. The high sensitivity and reproducibility of our Tamm-Horsfall protein assay will reduce the number of false negative results of the sample compared with enzyme-linked immunosorbent assay. Moreover, our method is superior to other high-performance liquid chromatography methods, and a simple protocol will facilitate further research on the physiological role of Tamm-Horsfall protein. © The Author(s) 2015.

  17. Ultra high performance liquid chromatography of seized drugs

    NARCIS (Netherlands)

    Lurie, I.S.

    2010-01-01

    The primary goal of this thesis is to investigate the use of ultra high performance liquid chromatography (UHPLC) for the analysis of seized drugs. This goal was largely achieved and significant progress was made in achieving improved separation and detection of drugs of forensic interest.

  18. Mallow carotenoids determined by high-performance liquid chromatography

    Science.gov (United States)

    Mallow (corchorus olitorius) is a green vegetable, which is widely consumed either fresh or dry by Middle East population. This study was carried out to determine the contents of major carotenoids quantitatively in mallow, by using a High Performance Liquid Chromatography (HPLC) equipped with a Bis...

  19. High-performance liquid chromatography-mass spectrometry-based acetylcholinesterase assay for the screening of inhibitors in natural extracts

    NARCIS (Netherlands)

    de Jong, C.F.; Derks, R.J.E.; Bruyneel, B.; Niessen, W.M.A.; Irth, H.

    2006-01-01

    The present paper describes a High-performance liquid chromatography-mass spectrometry (LC-MS) methodology for the screening of acetylcholinesterase (AChE) inhibitors in natural extracts. AChE activity of sample components is monitored by a post-column biochemical assay that is based on the

  20. performance liquid chromatography

    African Journals Online (AJOL)

    user

    2010-11-22

    Nov 22, 2010 ... ISSN 1684–5315 © 2010 Academic Journals. Full Length Research Paper. Determination ... Key words: Processed food, high-performance liquid chromatography, acrylamide, health hazard. INTRODUCTION. In the year 2002, the ... potatoes, breakfast cereals etc. It was thus confirmed that acrylamide has ...

  1. Analysis of short-chain acids from anaerobic bacteria by high-performance liquid chromatography.

    OpenAIRE

    Guerrant, G O; Lambert, M A; Moss, C W

    1982-01-01

    A standard mixture of 25 short-chain fatty acids was resolved by high-performance liquid chromatography, using an Aminex HPX-87 column. The acids produced in culture media by anaerobic bacteria were analyzed by high-performance liquid chromatography after extraction with ether and reextraction into a small volume of 0.1 N NaOH. The presence of fumaric acid in culture extracts of Peptostreptococcus anaerobius was confirmed by gas chromatography-mass spectrometry analysis of the trapped eluent ...

  2. Ultra-sensitive high performance liquid chromatography-laser-induced fluorescence based proteomics for clinical applications.

    Science.gov (United States)

    Patil, Ajeetkumar; Bhat, Sujatha; Pai, Keerthilatha M; Rai, Lavanya; Kartha, V B; Chidangil, Santhosh

    2015-09-08

    An ultra-sensitive high performance liquid chromatography-laser induced fluorescence (HPLC-LIF) based technique has been developed by our group at Manipal, for screening, early detection, and staging for various cancers, using protein profiling of clinical samples like, body fluids, cellular specimens, and biopsy-tissue. More than 300 protein profiles of different clinical samples (serum, saliva, cellular samples and tissue homogenates) from volunteers (normal, and different pre-malignant/malignant conditions) were recorded using this set-up. The protein profiles were analyzed using principal component analysis (PCA) to achieve objective detection and classification of malignant, premalignant and healthy conditions with high sensitivity and specificity. The HPLC-LIF protein profiling combined with PCA, as a routine method for screening, diagnosis, and staging of cervical cancer and oral cancer, is discussed in this paper. In recent years, proteomics techniques have advanced tremendously in life sciences and medical sciences for the detection and identification of proteins in body fluids, tissue homogenates and cellular samples to understand biochemical mechanisms leading to different diseases. Some of the methods include techniques like high performance liquid chromatography, 2D-gel electrophoresis, MALDI-TOF-MS, SELDI-TOF-MS, CE-MS and LC-MS techniques. We have developed an ultra-sensitive high performance liquid chromatography-laser induced fluorescence (HPLC-LIF) based technique, for screening, early detection, and staging for various cancers, using protein profiling of clinical samples like, body fluids, cellular specimens, and biopsy-tissue. More than 300 protein profiles of different clinical samples (serum, saliva, cellular samples and tissue homogenates) from healthy and volunteers with different malignant conditions were recorded by using this set-up. The protein profile data were analyzed using principal component analysis (PCA) for objective

  3. Quantification of Quercetin and Rutin from Benincasa hispida Seeds and Carissa Congesta Roots by High-performance Thin Layer Chromatography and High-performance Liquid Chromatography.

    Science.gov (United States)

    Doshi, Gaurav Mahesh; Une, Hemant Devidas

    2016-01-01

    In Indian Ayurvedic system, Benincasa hispida (BH) and Carissa congesta (CC) are well-known plants used for major and minor ailments. BH has been regarded as Kushmanda, whereas CC has been used in immune-related disorders of the human system. Quercetin and rutin identified from the vast plethora of plant extracts have proved to possess ethnopharmacological relevance. In present studies, we have determined quercetin and rutin in terms of percentage in BH seeds and CC roots by high-performance thin layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC). After extraction and phytochemical screening, the extracts were subjected to quantification for the presence of quercetin and rutin by HPTLC and HPLC. HPTLC showed quercetin as 44.60, 27.13% and rutin as 32.00, 36.31% w/w, whereas HPLC revealed quercetin as 34.00, 35.00% and rutin as 21.99, 45.03% w/v in BH and CC extracts, respectively. The BH and CC extracts have elucidated peaks that were corresponding with standard peaks on undertaking chromatographic studies. Quercetin and rutin are isolated from BH seeds and CC roots by High Performance. Thin Layer Chromatography and High Performance Liquid Chromatography. HPTLC revealed presence of quercetin as 44.60, 27.13 % and rutin as 32.00, 36.31 % w/w. HPLC revealed presence of quercetin as 34.00, 35.00 % and rutin as 21.99, 45.03 % w/v. Abbreviation Used: HPTLC: High Performance Thin Layer Chromatography; HPLC: High Pressure Liquid Chromatography, UV: Ultraviolet, CC: Carissa congesta, BH: Benincasa hispida.

  4. Quantification of Quercetin and Rutin from Benincasa hispida Seeds and Carissa Congesta Roots by High-performance Thin Layer Chromatography and High-performance Liquid Chromatography

    Science.gov (United States)

    Doshi, Gaurav Mahesh; Une, Hemant Devidas

    2016-01-01

    Objective: In Indian Ayurvedic system, Benincasa hispida (BH) and Carissa congesta (CC) are well-known plants used for major and minor ailments. BH has been regarded as Kushmanda, whereas CC has been used in immune-related disorders of the human system. Quercetin and rutin identified from the vast plethora of plant extracts have proved to possess ethnopharmacological relevance. Materials and Methods: In present studies, we have determined quercetin and rutin in terms of percentage in BH seeds and CC roots by high-performance thin layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC). After extraction and phytochemical screening, the extracts were subjected to quantification for the presence of quercetin and rutin by HPTLC and HPLC. Results: HPTLC showed quercetin as 44.60, 27.13% and rutin as 32.00, 36.31% w/w, whereas HPLC revealed quercetin as 34.00, 35.00% and rutin as 21.99, 45.03% w/v in BH and CC extracts, respectively. Conclusion: The BH and CC extracts have elucidated peaks that were corresponding with standard peaks on undertaking chromatographic studies. SUMMARY Quercetin and rutin are isolated from BH seeds and CC roots by High Performance. Thin Layer Chromatography and High Performance Liquid Chromatography. HPTLC revealed presence of quercetin as 44.60, 27.13 % and rutin as 32.00, 36.31 % w/w. HPLC revealed presence of quercetin as 34.00, 35.00 % and rutin as 21.99, 45.03 % w/v. Abbreviation Used: HPTLC: High Performance Thin Layer Chromatography; HPLC: High Pressure Liquid Chromatography, UV: Ultraviolet, CC: Carissa congesta, BH: Benincasa hispida PMID:26941534

  5. Coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry for arsenic speciation.

    Science.gov (United States)

    Cheng, Heyong; Shen, Lihuan; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao

    2018-04-01

    Nanoliter high-performance liquid chromatography shows low consumption of solvents and samples, offering one of the best choices for arsenic speciation in precious samples in combination with inuctively coupled plasma mass spectrometry. A systematic investigation on coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry from instrument design to injected sample volume and mobile phase was performed in this study. Nanoflow mobile phase was delivered by flow splitting using a conventional high-pressure pump with reuse of mobile phase waste. Dead volume was minimized to 60 nL for the sheathless interface based on the previously developed nanonebulizer. Capillary columns for nanoliter high-performance liquid chromatography were found to be sensitive to sample loading volume. An apparent difference was also found between the mobile phases for nanoliter and conventional high-performance liquid chromatography. Baseline separation of arsenite, arsenate, monomethylarsenic, and dimethylarsenic was achieved within 11 min on a 15 cm C 18 capillary column and within 12 min on a 25 cm strong anion exchange column. Detection limits of 0.9-1.8 μg/L were obtained with precisions variable in the range of 1.6-4.2%. A good agreement between determined and certified values of a certified reference material of human urine (GBW 09115) validated its accuracy along with good recoveries (87-102%). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Fractionation of fecal neutral steroids by high performance liquid chromatography

    International Nuclear Information System (INIS)

    Jackson, E.M.; Kloss, C.A.; Weintraub, S.T.; Mott, G.E.

    1985-01-01

    Fecal neutral steroids were fractionated by high performance liquid chromatography (HPLC) into three major fractions: 5 beta-H, 3-keto steroids; 5 beta-H, 3 beta-hydroxy steroids; and 5 alpha-H and delta 5-3 beta-hydroxy steroids. This separation was achieved in about 10 minutes, with greater than 97% recovery of standards in each fraction. Gas-liquid chromatographic quantitation of fecal steroids fractionated by either HPLC or thin-layer chromatography gave nearly identical results. A method using both C18 reverse phase and silica HPLC to purify radiolabeled sterols is also described

  7. Quality evaluation of moluodan concentrated pill using high-performance liquid chromatography fingerprinting coupled with chemometrics.

    Science.gov (United States)

    Tao, Lingyan; Zhang, Qing; Wu, Yongjiang; Liu, Xuesong

    2016-12-01

    In this study, a fast and effective high-performance liquid chromatography method was developed to obtain a fingerprint chromatogram and quantitative analysis simultaneously of four indexes including gallic acid, chlorogenic acid, albiflorin and paeoniflorin of the traditional Chinese medicine Moluodan Concentrated Pill. The method was performed by using a Waters X-bridge C 18 reversed phase column on an Agilent 1200S high-performance liquid chromatography system coupled with diode array detection. The mobile phase of the high-performance liquid chromatography method was composed of 20 mmol/L phosphate solution and acetonitrile with a 1 mL/min eluent velocity, under a detection temperature of 30°C and a UV detection wavelength of 254 nm. After the methodology validation, 16 batches of Moluodan Concentrated Pill were analyzed by this high-performance liquid chromatography method and both qualitative and quantitative evaluation results were achieved by similarity analysis, principal component analysis and hierarchical cluster analysis. The results of these three chemometrics were in good agreement and all indicated that batch 10 and batch 16 showed significant differences with the other 14 batches. This suggested that the developed high-performance liquid chromatography method could be applied in the quality evaluation of Moluodan Concentrated Pill. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Retention of nucleic acids in ion-pair reversed-phase high-performance liquid chromatography depends not only on base composition but also on base sequence.

    Science.gov (United States)

    Qiao, Jun-Qin; Liang, Chao; Wei, Lan-Chun; Cao, Zhao-Ming; Lian, Hong-Zhen

    2016-12-01

    The study on nucleic acid retention in ion-pair reversed-phase high-performance liquid chromatography mainly focuses on size-dependence, however, other factors influencing retention behaviors have not been comprehensively clarified up to date. In this present work, the retention behaviors of oligonucleotides and double-stranded DNAs were investigated on silica-based C 18 stationary phase by ion-pair reversed-phase high-performance liquid chromatography. It is found that the retention of oligonucleotides was influenced by base composition and base sequence as well as size, and oligonucleotides prone to self-dimerization have weaker retention than those not prone to self-dimerization but with the same base composition. However, homo-oligonucleotides are suitable for the size-dependent separation as a special case of oligonucleotides. For double-stranded DNAs, the retention is also influenced by base composition and base sequence, as well as size. This may be attributed to the interaction of exposed bases in major or minor grooves with the hydrophobic alky chains of stationary phase. In addition, no specific influence of guanine and cytosine content was confirmed on retention of double-stranded DNAs. Notably, the space effect resulted from the stereostructure of nucleic acids also influences the retention behavior in ion-pair reversed-phase high-performance liquid chromatography. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Monitoring aged reversed-phase high performance liquid chromatography columns

    NARCIS (Netherlands)

    Bolck, A; Smilde, AK; Bruins, CHP

    1999-01-01

    In this paper, a new approach for the quality assessment of routinely used reversed-phase high performance liquid chromatography columns is presented. A used column is not directly considered deteriorated when changes in retention occur. If attention is paid to the type and magnitude of the changes,

  10. Quantification of Tea Flavonoids by High Performance Liquid Chromatography

    Science.gov (United States)

    Freeman, Jessica D.; Niemeyer, Emily D.

    2008-01-01

    We have developed a laboratory experiment that uses high performance liquid chromatography (HPLC) to quantify flavonoid levels in a variety of commercial teas. Specifically, this experiment analyzes a group of flavonoids known as catechins, plant-derived polyphenolic compounds commonly found in many foods and beverages, including green and black…

  11. Ionic-liquid-based ultrasound-assisted extraction of isoflavones from Belamcanda chinensis and subsequent screening and isolation of potential α-glucosidase inhibitors by ultrafiltration and semipreparative high-performance liquid chromatography.

    Science.gov (United States)

    Li, Senlin; Li, Sainan; Huang, Yu; Liu, Chunming; Chen, Lina; Zhang, Yuchi

    2017-06-01

    The separation of a compound of interest from its structurally similar homologues to produce high-purity natural products is a challenging problem. This work proposes a novel method for the separation of iristectorigenin A from its structurally similar homologues by ionic-liquid-based ultrasound-assisted extraction and the subsequent screening and isolation of potential α-glucosidase inhibitors via ultrafiltration and semipreparative high-performance liquid chromatography. Ionic-liquid-based ultrasound-assisted extraction was successfully applied to the extraction of tectorigenin, iristectorigenin A, irigenin, and irisflorentin from Belamcanda chinensis. The optimum conditions for the efficient extraction of isoflavones were determined as 1.0 M 1-ethyl-3-methylimidazolium tetrafluoroborate with extraction time of 30 min and a solvent to solid ratio of 30 mL/g. Ultrafiltration with liquid chromatography and mass spectrometry was applied to screen and identify α-glucosidase inhibitors from B. chinensis, followed by the application of semipreparative high-performance liquid chromatography to separate and isolate the active constituents. Four major compounds including tectorigenin, iristectorigenin A, irigenin, and irisflorentin were screened and identified as α-glucosidase inhibitors, and then the four active compounds abovementioned were subsequently isolated by semipreparative high-performance liquid chromatography (99.89, 88.97, 99.79, and 99.97% purity, respectively). The results demonstrate that ionic liquid extraction can be successfully applied to the extraction of isoflavones from B. chinensis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Combined high-performance liquid chromatography-radioimmunoassay for cytokinins

    International Nuclear Information System (INIS)

    MacDonald, E.M.S.; Akiyoshi, D.E.; Morris, R.O.

    1981-01-01

    The cytokinins isopentenyladenosine and ribosylzeatin were conjugated to bovine serum albumin and the conjugates used to raise antisera in rabbits. The resulting antisera had high specificity towards the cytokinin haptens and low cross-reactivity towards other purines. They were used as the basis for a radioimmunoassay for cytokinins, which, when applied in conjunction with high-performance liquid chromatography, allowed rapid and sensitive (to the picogram range) estimation and identification of multiple cytokinins from natural plant and bacterial sources. (orig.)

  13. High-Performance Liquid Chromatography in the Undergraduate Chemical Engineering Laboratory

    Science.gov (United States)

    Frey, Douglas D.; Guo, Hui; Karnik, Nikhila

    2013-01-01

    This article describes the assembly of a simple, low-cost, high-performance liquid chromatography (HPLC) system and its use in the undergraduate chemical engineering laboratory course to perform simple experiments. By interpreting the results from these experiments students are able to gain significant experience in the general method of…

  14. Application of Ionic Liquids in High Performance Reversed-Phase Chromatography

    Directory of Open Access Journals (Sweden)

    Wentao Bi

    2009-06-01

    Full Text Available Ionic liquids, considered “green” chemicals, are widely used in many areas of analytical chemistry due to their unique properties. Recently, ionic liquids have been used as a kind of novel additive in separation and combined with silica to synthesize new stationary phase as separation media. This review will focus on the properties and mechanisms of ionic liquids and their potential applications as mobile phase modifier and surface-bonded stationary phase in reversed-phase high performance liquid chromatography (RP-HPLC. Ionic liquids demonstrate advantages and potential in chromatographic field.

  15. Determination of diflubenzuron and chlorbenzuron in fruits by combining acetonitrile-based extraction with dispersive liquid-liquid microextraction followed by high-performance liquid chromatography.

    Science.gov (United States)

    Ruan, Chunqiang; Zhao, Xiang; Liu, Chenglan

    2015-09-01

    In this study, a simple and low-organic-solvent-consuming method combining an acetonitrile-partitioning extraction procedure followed by "quick, easy, cheap, effective, rugged and safe" cleanup with ionic-liquid-based dispersive liquid-liquid microextraction and high-performance liquid chromatography with diode array detection was developed for the determination of diflubenzuron and chlorbenzuron in grapes and pears. Ionic-liquid-based dispersive liquid-liquid microextraction was performed using the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate as the extractive solvent and acetonitrile extract as the dispersive solvent. The main factors influencing the efficiency of the dispersive liquid-liquid microextraction were evaluated, including the extractive solvent type and volume and the dispersive solvent volume. The validation parameters indicated the suitability of the method for routine analyses of benzoylurea insecticides in a large number of samples. The relative recoveries at three spiked levels ranged between 98.6 and 109.3% with relative standard deviations of less than 5.2%. The limit of detection was 0.005 mg/kg for the two insecticides. The proposed method was successfully used for the rapid determination of diflubenzuron and chlorbenzuron residues in real fruit samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Determination of Caffeine in Beverages by High Performance Liquid Chromatography.

    Science.gov (United States)

    DiNunzio, James E.

    1985-01-01

    Describes the equipment, procedures, and results for the determination of caffeine in beverages by high performance liquid chromatography. The method is simple, fast, accurate, and, because sample preparation is minimal, it is well suited for use in a teaching laboratory. (JN)

  17. High-Performance Liquid Chromatography (HPLC)-Based Detection and Quantitation of Cellular c-di-GMP.

    Science.gov (United States)

    Petrova, Olga E; Sauer, Karin

    2017-01-01

    The modulation of c-di-GMP levels plays a vital role in the regulation of various processes in a wide array of bacterial species. Thus, investigation of c-di-GMP regulation requires reliable methods for the assessment of c-di-GMP levels and turnover. Reversed-phase high-performance liquid chromatography (RP-HPLC) analysis has become a commonly used approach to accomplish these goals. The following describes the extraction and HPLC-based detection and quantification of c-di-GMP from Pseudomonas aeruginosa samples, a procedure that is amenable to modifications for the analysis of c-di-GMP in other bacterial species.

  18. Fast and comprehensive analysis of secondary metabolites in cocoa products using ultra high-performance liquid chromatography directly after pressurized liquid extraction.

    Science.gov (United States)

    Damm, Irina; Enger, Eileen; Chrubasik-Hausmann, Sigrun; Schieber, Andreas; Zimmermann, Benno F

    2016-08-01

    Fast methods for the extraction and analysis of various secondary metabolites from cocoa products were developed and optimized regarding speed and separation efficiency. Extraction by pressurized liquid extraction is automated and the extracts are analyzed by rapid reversed-phase ultra high-performance liquid chromatography and normal-phase high-performance liquid chromatography methods. After extraction, no further sample treatment is required before chromatographic analysis. The analytes comprise monomeric and oligomeric flavanols, flavonols, methylxanthins, N-phenylpropenoyl amino acids, and phenolic acids. Polyphenols and N-phenylpropenoyl amino acids are separated in a single run of 33 min, procyanidins are analyzed by normal-phase high-performance liquid chromatography within 16 min, and methylxanthins require only 6 min total run time. A fourth method is suitable for phenolic acids, but only protocatechuic acid was found in relevant quantities. The optimized methods were validated and applied to 27 dark chocolates, one milk chocolate, two cocoa powders and two food supplements based on cocoa extract. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Preparation and evaluation of surface-bonded tricationic ionic liquid silica as stationary phases for high-performance liquid chromatography.

    Science.gov (United States)

    Qiao, Lizhen; Shi, Xianzhe; Lu, Xin; Xu, Guowang

    2015-05-29

    Two tricationic ionic liquids were prepared and then bonded onto the surface of supporting silica materials through "thiol-ene" click chemistry as new stationary phases for high-performance liquid chromatography. The obtained columns of tricationic ionic liquids were evaluated respectively in the reversed-phase liquid chromatography (RPLC) mode and hydrophilic interaction liquid chromatography (HILIC) mode, and possess ideal column efficiency of 80,000 plates/m in the RPLC mode with naphthalene as the test solute. The tricationic ionic liquid stationary phases exhibit good hydrophobic and shape selectivity to hydrophobic compounds, and RPLC retention behavior with multiple interactions. In the HILIC mode, the retention and selectivity were evaluated through the efficient separation of nucleosides and bases as well as flavonoids, and the typical HILIC retention behavior was demonstrated by investigating retention changes of hydrophilic solutes with water volume fraction in mobile phase. The results show that the tricationic ionic liquid columns possess great prospect for applications in analysis of hydrophobic and hydrophilic samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Rapid pretreatment and determination of bisphenol A in water samples based on vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Yang, Xiao; Diao, Chun-Peng; Sun, Ai-Ling; Liu, Ren-Min

    2014-10-01

    A method for the rapid pretreatment and determination of bisphenol A in water samples based on vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with fluorescence detection was proposed in this paper. A simple apparatus consisting of a test tube and a cut-glass dropper was designed and applied to collect the floating extraction drop in liquid-liquid microextraction when low-density organic solvent was used as the extraction solvent. Solidification and melting steps that were tedious but necessary once the low-density organic solvent used as extraction solvent could be avoided by using this apparatus. Bisphenol A was selected as model pollutant and vortex-assisted liquid-liquid microextraction was employed to investigate the usefulness of the apparatus. High-performance liquid chromatography with fluorescence detection was selected as the analytical tool for the detection of bisphenol A. The linear dynamic range was from 0.10 to 100 μg/L for bisphenol A, with good squared regression coefficient (r(2) = 0.9990). The relative standard deviation (n = 7) was 4.7% and the limit of detection was 0.02 μg/L. The proposed method had been applied to the determination of bisphenol A in natural water samples and was shown to be economical, fast, and convenient. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Assay for dihydroorotase using high-performance liquid chromatography with radioactivity detection

    International Nuclear Information System (INIS)

    Mehdi, S.; Wiseman, J.S.

    1989-01-01

    An assay for measuring dihydroorotase activity was devised. Radiolabeled substrate and product were separated by high-performance liquid chromatography using a reverse-phase column with ion-pairing, and the radioactivity was quantitated by flow detection

  2. High perfomance liquid chromatography in pharmaceutical analyses.

    Science.gov (United States)

    Nikolin, Branko; Imamović, Belma; Medanhodzić-Vuk, Saira; Sober, Miroslav

    2004-05-01

    In testing the pre-sale procedure the marketing of drugs and their control in the last ten years, high performance liquid chromatography replaced numerous spectroscopic methods and gas chromatography in the quantitative and qualitative analysis. In the first period of HPLC application it was thought that it would become a complementary method of gas chromatography, however, today it has nearly completely replaced gas chromatography in pharmaceutical analysis. The application of the liquid mobile phase with the possibility of transformation of mobilized polarity during chromatography and all other modifications of mobile phase depending upon the characteristics of substance which are being tested, is a great advantage in the process of separation in comparison to other methods. The greater choice of stationary phase is the next factor which enables realization of good separation. The separation line is connected to specific and sensitive detector systems, spectrafluorimeter, diode detector, electrochemical detector as other hyphernated systems HPLC-MS and HPLC-NMR, are the basic elements on which is based such wide and effective application of the HPLC method. The purpose high performance liquid chromatography (HPLC) analysis of any drugs is to confirm the identity of a drug and provide quantitative results and also to monitor the progress of the therapy of a disease.1) Measuring presented on the Fig. 1. is chromatogram obtained for the plasma of depressed patients 12 h before oral administration of dexamethasone. It may also be used to further our understanding of the normal and disease process in the human body trough biomedical and therapeutically research during investigation before of the drugs registration. The analyses of drugs and metabolites in biological fluids, particularly plasma, serum or urine is one of the most demanding but one of the most common uses of high performance of liquid chromatography. Blood, plasma or serum contains numerous endogenous

  3. Characterization of natural organic colorants in historical and art objects by high-performance liquid chromatography.

    Science.gov (United States)

    Pauk, Volodymyr; Barták, Petr; Lemr, Karel

    2014-12-01

    High-performance liquid chromatography plays an important role in analysis of historical organic colorants. A number of papers have been published in this field over the last 30 years. Classification of the most commonly used natural dyes and an overview of high-performance liquid chromatography methods with main focus on recent works (2008 to the beginning of 2014) are provided. The review deals with an entire analytical protocol covering sample preparation, chromatographic separation, and suitable detection (UV/visible and fluorescent spectroscopy and mass spectrometric techniques). High-performance liquid chromatography has been successfully used in the complete characterization of some organic dyestuffs present in historical and art objects. The possibilities and difficulties for identification of natural sources of historical colorants are also discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Separation of enantiomers of new psychoactive substances by high-performance liquid chromatography.

    Science.gov (United States)

    Kadkhodaei, Kian; Forcher, Lisa; Schmid, Martin G

    2018-03-01

    New psychoactive substances are defined as compounds with consciousness-changing effects and have been developed simultaneously with classical drugs. They arise through structural modifications of illegal substances and are mainly produced to circumvent laws. Availability is simple, since new psychoactive substances can be purchased from the Internet. Among them many chemical drug compound classes are chiral and thus the two resulting enantiomers can differ in their effects. The aim of this study is to develop a suitable chiral high-performance liquid chromatography separation method for a broad spectrum of new psychoactive substances using cellulose tris(3,5-dichlorophenylcarbamate) as a chiral selector. Experiments were performed by high-performance liquid chromatography in normal-phase mode under isocratic conditions using ultraviolet detection. Direct separation was carried out on a high-performance liquid chromatography column (Lux® i-Cellulose-5, 3.5 μm, Phenomenex®), available since 2016. Excellent separation results were obtained for cathinones. After further optimization, even 47 instead of 39 out of 52 cathinones showed baseline separation. For amphetamine derivatives, satisfactory results were not achieved. Further, new psychoactive substances from other compound classes such as benzofuranes, thiophenes, phenidines, phenidates, morpholines, and ketamines were partially resolved, depending on the polarity and degree of substitution. All analytes, which were mainly purchased from the Internet, were proven to be traded as racemates. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Determination of chloroacetanilide herbicide metabolites in water using high-performance liquid chromatography-diode array detection and high-performance liquid chromatography/mass spectrometry

    Science.gov (United States)

    Hostetler, K.A.; Thurman, E.M.

    2000-01-01

    Analytical methods using high-performance liquid chromatography-diode array detection (HPLC-DAD) and high-performance liquid chromatography/mass spectrometry (HPLC/MS) were developed for the analysis of the following chloroacetanilide herbicide metabolites in water: alachlor ethanesulfonic acid (ESA); alachlor oxanilic acid; acetochlor ESA; acetochlor oxanilic acid; metolachlor ESA; and metolachlor oxanilic acid. Good precision and accuracy were demonstrated for both the HPLC-DAD and HPLC/MS methods in reagent water, surface water, and ground water. The average HPLC-DAD recoveries of the chloroacetanilide herbicide metabolites from water samples spiked at 0.25, 0.5 and 2.0 ??g/l ranged from 84 to 112%, with relative standard deviations of 18% or less. The average HPLC/MS recoveries of the metabolites from water samples spiked at 0.05, 0.2 and 2.0 ??g/l ranged from 81 to 118%, with relative standard deviations of 20% or less. The limit of quantitation (LOQ) for all metabolites using the HPLC-DAD method was 0.20 ??g/l, whereas the LOQ using the HPLC/MS method was at 0.05 ??g/l. These metabolite-determination methods are valuable for acquiring information about water quality and the fate and transport of the parent chloroacetanilide herbicides in water. Copyright (C) 2000 Elsevier Science B.V.

  6. High-performance liquid chromatography analysis methods developed for quantifying enzymatic esterification of flavonoids in ionic liquids

    DEFF Research Database (Denmark)

    Lue, Bena-Marie; Guo, Zheng; Xu, X.B.

    2008-01-01

    Methods using reversed-phase high-performance liquid chromatography (RP-HPLC) with ELSD were investigated to quantify enzymatic reactions of flavonoids with fatty acids in the presence of diverse room temperature ionic liquids (RTILs). A buffered salt (preferably triethylamine-acetate) was found...... essential for separation of flavonoids from strongly polar RTILs, whereby RTILs were generally visible as two major peaks identified based on an ion-pairing/exchanging hypothesis. C8 and C12 stationary phases were optimal while mobile phase pH (3-7) had only a minor influence on separation. The method...

  7. Assessing the detectability of antioxidants in two-dimensional high-performance liquid chromatography.

    Science.gov (United States)

    Bassanese, Danielle N; Conlan, Xavier A; Barnett, Neil W; Stevenson, Paul G

    2015-05-01

    This paper explores the analytical figures of merit of two-dimensional high-performance liquid chromatography for the separation of antioxidant standards. The cumulative two-dimensional high-performance liquid chromatography peak area was calculated for 11 antioxidants by two different methods--the areas reported by the control software and by fitting the data with a Gaussian model; these methods were evaluated for precision and sensitivity. Both methods demonstrated excellent precision in regards to retention time in the second dimension (%RSD below 1.16%) and cumulative second dimension peak area (%RSD below 3.73% from the instrument software and 5.87% for the Gaussian method). Combining areas reported by the high-performance liquid chromatographic control software displayed superior limits of detection, in the order of 1 × 10(-6) M, almost an order of magnitude lower than the Gaussian method for some analytes. The introduction of the countergradient eliminated the strong solvent mismatch between dimensions, leading to a much improved peak shape and better detection limits for quantification. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Screening anti-tumor compounds from Ligusticum wallichii using cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry.

    Science.gov (United States)

    Zhang, Tao; Ding, Yuanyuan; An, Hongli; Feng, Liuxin; Wang, Sicen

    2015-07-14

    Tyrosine 367 Cysteine-fibroblast growth factor receptor 4 cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry was developed. Tyrosine 367 Cysteine-HEK293 cells were used as cell membrane stationary phase. Specificity and reproducibility of the cell membrane chromatography was evaluated using 1-tert-butyl-3-{2-[4-(diethylamino)butylamino]-6-(3,5-dimethoxyphenyl)pyrido[2,3-d]pyrimidin-7-yl}urea, Nimodipine and dexamethasone acetate. Then, anti-tumor components acting on Tyrosine 367 Cysteine-fibroblast growth factor receptor 4 were screened and identified from extracts of Ligusticum wallichii. Components from the extract were retained on the cell membrane chromatographic column. The retained fraction was directly eluted into high-performance liquid chromatography with mass spectrometry system for separation and identification. Finally, Levistolide A was identified as an active component from Ligusticum wallichii extracts. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide-formazan colorimetric assay revealed that Levistolide A inhibits proliferation of overexpressing the mutated receptor cells with dose-dependent manner. Phosphorylation of fibroblast growth factor receptor 4 was also decrease under Levistolide A treatment. Flex dock simulation verified that Levistolide A could bind with the tyrosine kinase domain of fibroblast growth factor receptor 4. Therefore, Levistolide A screened by the cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry can arrest cell growth. In conclusion, the two-dimensional high-performance liquid chromatography method can screen and identify potential anti-tumor ingredients which specifically act on the tyrosine kinase domain of the mutated fibroblast growth factor receptor 4. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Simultaneous determination of niacin and pyridoxine at trace levels by using diode array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry.

    Science.gov (United States)

    Sel, Sabriye; Öztürk Er, Elif; Bakırdere, Sezgin

    2017-12-01

    A highly sensitive and simple diode-array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry method was developed for the simultaneous determination of niacin and pyridoxine in pharmaceutical drugs, tap water, and wastewater samples. To determine the in vivo behavior of niacin and pyridoxine, analytes were subjected to simulated gastric conditions. The calibration plots of the diode-array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry method showed good linearity over a wide concentration range with close to 1.0 correlation coefficients for both analytes. The limit of detection/limit of quantitation values for liquid chromatography quadrupole time-of-flight tandem mass spectrometry analysis were 1.98/6.59 and 1.3/4.4 μg/L for niacin and pyridoxine, respectively, while limit of detection/limit of quantitation values for niacin and pyridoxine in high-performance liquid chromatography analysis were 3.7/12.3 and 5.7/18.9 μg/L, respectively. Recovery studies were also performed to show the applicability of the developed methods, and percentage recovery values were found to be 90-105% in tap water and 94-97% in wastewater for both analytes. The method was also successfully applied for the qualitative and quantitative determination of niacin and pyridoxine in drug samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. High performance liquid chromatography in studies of radiolabeled antibodies

    International Nuclear Information System (INIS)

    Hnatowich, D.J.

    1986-01-01

    High performance liquid chromatography (HPLC) as applied to the separation of antibodies displays the same advantages as in its other applications, namely good resolution accompanied by fast analysis. It is therefore not surprising that many HPLC columns designed for use with antibodies and other proteins are now available commercially. The properties of proteins which provide the separation are size, hydrophobicity, charge and affinity. The features of each are discussed. (author)

  11. High Performance Liquid Chromatography Experiments to Undergraduate Laboratories

    Science.gov (United States)

    Kissinger, Peter T.; And Others

    1977-01-01

    Reviews the principles of liquid chromatography with electrochemical detection (LCEC), an analytical technique that incorporates the advantages of both liquids chromatography and electrochemistry. Also suggests laboratory experiments using this technique. (MLH)

  12. Ionic liquid-based air-assisted liquid-liquid microextraction followed by high performance liquid chromatography for the determination of five fungicides in juice samples.

    Science.gov (United States)

    You, Xiangwei; Chen, Xiaochu; Liu, Fengmao; Hou, Fan; Li, Yiqiang

    2018-01-15

    A novel and simple ionic liquid-based air-assisted liquid-liquid microextraction technique combined with high performance liquid chromatography was developed to analyze five fungicides in juice samples. In this method, ionic liquid was used instead of a volatile organic solvent as the extraction solvent. The emulsion was formed by pulling in and pushing out the mixture of aqueous sample solution and extraction solvent repeatedly using a 10mL glass syringe. No organic dispersive solvent was required. Under the optimized conditions, the limits of detection (LODs) were 0.4-1.8μgL -1 at a signal-to-noise ratio of 3. The limits of quantification (LOQs) set as the lowest spiking levels with acceptable recovery in juices were 10μgL -1 , except for fludioxonil whose LOQ was 20μgL -1 . The proposed method was applied to determine the target fungicides in juice samples, and acceptable recoveries ranging from 74.9% to 115.4% were achieved. Copyright © 2017. Published by Elsevier Ltd.

  13. Chromatographic behavior of small organic compounds in low-temperature high-performance liquid chromatography using liquid carbon dioxide as the mobile phase.

    Science.gov (United States)

    Motono, Tomohiro; Nagai, Takashi; Kitagawa, Shinya; Ohtani, Hajime

    2015-07-01

    Low-temperature high-performance liquid chromatography, in which a loop injector, column, and detection cell were refrigerated at -35ºC, using liquid carbon dioxide as the mobile phase was developed. Small organic compounds (polyaromatic hydrocarbons, alkylbenzenes, and quinones) were separated by low-temperature high-performance liquid chromatography at temperatures from -35 to -5ºC. The combination of liquid carbon dioxide mobile phase with an octadecyl-silica (C18 ) column provided reversed phase mode separation, and a bare silica-gel column resulted in normal phase mode separation. In both the cases, nonlinear behavior at approximately -15ºC was found in the relationship between the temperature and the retention factors of the analytes (van't Hoff plots). In contrast to general trends in high-performance liquid chromatography, the decrease in temperature enhanced the separation efficiency of both the columns. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Determination of atenolol in human plasma using ionic-liquid-based ultrasound-assisted in situ solvent formation microextraction followed by high-performance liquid chromatography.

    Science.gov (United States)

    Zeeb, Mohsen; Farahani, Hadi; Papan, Mohammad Kazem

    2016-06-01

    An efficient analytical method called ionic-liquid-based ultrasound-assisted in situ solvent formation microextraction followed by high-performance liquid chromatography was developed for the determination of atenolol in human plasma. A hydrophobic ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) was formed by the addition of a hydrophilic ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) to a sample solution containing an ion-pairing agent during microextraction. The analyte was extracted into the ionic liquid phase while the microextraction solvent was dispersed throughout the sample by utilizing ultrasound. The sample was then centrifuged, and the extracting phase retracted into the microsyringe and injected to liquid chromatography. After optimization, the calibration curve showed linearity in the range of 2-750 ng/mL with the regression coefficient corresponding to 0.998. The limits of detection (S/N = 3) and quantification (S/N = 10) were 0.5 and 2 ng/mL, respectively. A reasonable relative recovery range of 90-96.7% and satisfactory intra-assay (4.8-5.1%, n = 6) and interassay (5.0-5.6%, n = 9) precision along with a substantial sample clean-up demonstrated good performance of the procedure. It was applied for the determination of atenolol in human plasma after oral administration and some pharmacokinetic data were obtained. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Rapid quantitative analysis of individual anthocyanin content based on high-performance liquid chromatography with diode array detection with the pH differential method.

    Science.gov (United States)

    Wang, Huayin

    2014-09-01

    A new quantitative technique for the simultaneous quantification of the individual anthocyanins based on the pH differential method and high-performance liquid chromatography with diode array detection is proposed in this paper. The six individual anthocyanins (cyanidin 3-glucoside, cyanidin 3-rutinoside, petunidin 3-glucoside, petunidin 3-rutinoside, and malvidin 3-rutinoside) from mulberry (Morus rubra) and Liriope platyphylla were used for demonstration and validation. The elution of anthocyanins was performed using a C18 column with stepwise gradient elution and individual anthocyanins were identified by high-performance liquid chromatography with tandem mass spectrometry. Based on the pH differential method, the high-performance liquid chromatography peak areas of maximum and reference absorption wavelengths of anthocyanin extracts were conducted to quantify individual anthocyanins. The calibration curves for these anthocyanins were linear within the range of 10-5500 mg/L. The correlation coefficients (r(2)) all exceeded 0.9972, and the limits of detection were in the range of 1-4 mg/L at a signal-to-noise ratio ≥5 for these anthocyanins. The proposed quantitative analysis was reproducible with good accuracy of all individual anthocyanins ranging from 96.3 to 104.2% and relative recoveries were in the range 98.4-103.2%. The proposed technique is performed without anthocyanin standards and is a simple, rapid, accurate, and economical method to determine individual anthocyanin contents. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. An Advanced, Interactive, High-Performance Liquid Chromatography Simulator and Instructor Resources

    Science.gov (United States)

    Boswell, Paul G.; Stoll, Dwight R.; Carr, Peter W.; Nagel, Megan L.; Vitha, Mark F.; Mabbott, Gary A.

    2013-01-01

    High-performance liquid chromatography (HPLC) simulation software has long been recognized as an effective educational tool, yet many of the existing HPLC simulators are either too expensive, outdated, or lack many important features necessary to make them widely useful for educational purposes. Here, a free, open-source HPLC simulator is…

  17. 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…

  18. Incorporation of ionic liquid into porous polymer monoliths to enhance the separation of small molecules in reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Wang, Jiafei; Bai, Ligai; Wei, Zhen; Qin, Junxiao; Ma, Yamin; Liu, Haiyan

    2015-06-01

    An ionic liquid was incorporated into the porous polymer monoliths to afford stationary phases with enhanced chromatographic performance for small molecules in reversed-phase high-performance liquid chromatography. The effect of the ionic liquid in the polymerization mixture on the performance of the monoliths was studied in detail. While monoliths without ionic liquid exhibited poor resolution and low efficiency, the addition of ionic liquid to the polymerization mixture provides highly increased resolution and high efficiency. The chromatographic performances of the monoliths were demonstrated by the separations of various small molecules including aromatic hydrocarbons, isomers, and homologues using a binary polar mobile phase. The present column efficiency reached 27 000 plates/m, which showed that the ionic liquid monoliths are alternative stationary phases in the separation of small molecules by high-performance liquid chromatography. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Separation of hemagglutination-inhibiting immunoglobulin M antibody to rubella virus in human serum by high-performance liquid chromatography.

    OpenAIRE

    Kobayashi, N; Suzuki, M; Nakagawa, T; Matumoto, M

    1986-01-01

    High-performance liquid chromatography was successfully used to separate hemagglutination-inhibiting immunoglobulin M (IgM) rubella virus antibody from IgG rubella virus antibody in human serum. The fractionation by high-performance liquid chromatography was as effective as sucrose density gradient centrifugation in separating IgM antibody from IgG antibody.

  20. Quantitative analysis of benzodiazepines in vitreous humor by high-performance liquid chromatography

    Science.gov (United States)

    Bazmi, Elham; Behnoush, Behnam; Akhgari, Maryam; Bahmanabadi, Leila

    2016-01-01

    Objective: Benzodiazepines are frequently screened drugs in emergency toxicology, drugs of abuse testing, and in forensic cases. As the variations of benzodiazepines concentrations in biological samples during bleeding, postmortem changes, and redistribution could be biasing forensic medicine examinations, hence selecting a suitable sample and a validated accurate method is essential for the quantitative analysis of these main drug categories. The aim of this study was to develop a valid method for the determination of four benzodiazepines (flurazepam, lorazepam, alprazolam, and diazepam) in vitreous humor using liquid–liquid extraction and high-performance liquid chromatography. Methods: Sample preparation was carried out using liquid–liquid extraction with n-hexane: ethyl acetate and subsequent detection by high-performance liquid chromatography method coupled to diode array detector. This method was applied to quantify benzodiazepines in 21 authentic vitreous humor samples. Linear curve for each drug was obtained within the range of 30–3000 ng/mL with coefficient of correlation higher than 0.99. Results: The limit of detection and quantitation were 30 and 100 ng/mL respectively for four drugs. The method showed an appropriate intra- and inter-day precision (coefficient of variation forensic toxicology laboratory. PMID:27635251

  1. Determination of trimethyllead reference material using high performance liquid chromatography-inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Lu Hai; Wei Chao; Wang Jun; Chao Jingbo; Zhou Tao; Chen Dazhou

    2005-01-01

    A high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) was combined, and the chromatography conditions were optimized. The stability and homogeneity of a trimethyllead reference material were determined using this method. (authors)

  2. Surface-bonded ionic liquid stationary phases in high-performance liquid chromatography--a review.

    Science.gov (United States)

    Pino, Verónica; Afonso, Ana M

    2012-02-10

    Ionic liquids (ILs) are a class of ionic, nonmolecular solvents which remain in liquid state at temperatures below 100°C. ILs possess a variety of properties including low to negligible vapor pressure, high thermal stability, miscibility with water or a variety of organic solvents, and variable viscosity. IL-modified silica as novel high-performance liquid chromatography (HPLC) stationary phases have attracted considerable attention for their differential behavior and low free-silanol activity. Indeed, around 21 surface-confined ionic liquids (SCIL) stationary phases have been developed in the last six years. Their chromatographic behavior has been studied, and, despite the presence of a positive charge on the stationary phase, they showed considerable promise for the separation of neutral solutes (not only basic analytes), when operated in reversed phase mode. This aspect points to the potential for truly multimodal stationary phases. This review attempts to summarize the state-of-the-art about SCIL phases including their preparation, chromatographic behavior, and analytical performance. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Sensitive determination of nitrophenol isomers by reverse-phase high-performance liquid chromatography in conjunction with liquid-liquid extraction

    Science.gov (United States)

    A method for the highly sensitive determination of 2-, 3- and 4- nitrophenols was developed using reverse-phase high-performance liquid chromatography (RP-HPLC) with a UV photodiode array detector. Using a reverse-phase column and 40% aqueous acetonitrile as an eluent (i.e. isocratic elution), the i...

  4. Determination of Urine Albumin by New Simple High-Performance Liquid Chromatography Method.

    Science.gov (United States)

    Klapkova, Eva; Fortova, Magdalena; Prusa, Richard; Moravcova, Libuse; Kotaska, Karel

    2016-11-01

    A simple high-performance liquid chromatography (HPLC) method was developed for the determination of albumin in patients' urine samples without coeluting proteins and was compared with the immunoturbidimetric determination of albumin. Urine albumin is important biomarker in diabetic patients, but part of it is immuno-nonreactive. Albumin was determined by high-performance liquid chromatography (HPLC), UV detection at 280 nm, Zorbax 300SB-C3 column. Immunoturbidimetric analysis was performed using commercial kit on automatic biochemistry analyzer COBAS INTEGRA ® 400, Roche Diagnostics GmbH, Manheim, Germany. The HLPC method was fully validated. No significant interference with other proteins (transferrin, α-1-acid glycoprotein, α-1-antichymotrypsin, antitrypsin, hemopexin) was found. The results from 301 urine samples were compared with immunochemical determination. We found a statistically significant difference between these methods (P = 0.0001, Mann-Whitney test). New simple HPLC method was developed for the determination of urine albumin without coeluting proteins. Our data indicate that the HPLC method is highly specific and more sensitive than immunoturbidimetry. © 2016 Wiley Periodicals, Inc.

  5. Analysis of new psychoactive substances in human urine by ultra-high performance supercritical fluid and liquid chromatography: Validation and comparison.

    Science.gov (United States)

    Borovcová, Lucie; Pauk, Volodymyr; Lemr, Karel

    2018-05-01

    New psychoactive substances represent serious social and health problem as tens of new compounds are detected in Europe annually. They often show structural proximity or even isomerism, which complicates their analysis. Two methods based on ultra high performance supercritical fluid chromatography and ultra high performance liquid chromatography with mass spectrometric detection were validated and compared. A simple dilute-filter-and-shoot protocol utilizing propan-2-ol or methanol for supercritical fluid or liquid chromatography, respectively, was proposed to detect and quantify 15 cathinones and phenethylamines in human urine. Both methods offered fast separation (chromatography. Limits of detection in urine ranged from 0.01 to 2.3 ng/mL, except for cathinone (5 ng/mL) in supercritical fluid chromatography. Nevertheless, this technique distinguished all analytes including four pairs of isomers, while liquid chromatography was unable to resolve fluoromethcathinone regioisomers. Concerning matrix effects and recoveries, supercritical fluid chromatography produced more uniform results for different compounds and at different concentration levels. This work demonstrates the performance and reliability of supercritical fluid chromatography and corroborates its applicability as an alternative tool for analysis of new psychoactive substances in biological matrixes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Hydrazine Determination in Sludge Samples by High Performance Liquid Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    G. Elias; G. A. Park

    2006-02-01

    A high-performance liquid chromatographic method using ultraviolet (UV) detection was developed to detect and quantify hydrazine in a variety of environmental matrices. The method was developed primarily for sludge samples, but it is also applicable to soil and water samples. The hydrazine in the matrices was derivatized to their hydrazones with benzaldehyde. The derivatized hydrazones were separated using high performance liquid chromatography (HPLC) with a reversed-phase C-18 column in an isocratic mode with methanol-water (95:5, v/v), and detected with UV detection at 313 nm. The detection limit (25 ml) for the new analytical method is 0.0067 mg ml-1of hydrazine. Hydrazine showed low recovery in soil samples because components in soil oxidized hydrazine. Sludge samples that contained relatively high soil content also showed lower recovery. The technique is relatively simple and cost-effective, and is applicable for hydrazine analysis in different environmental matrices.

  7. Optimization of the combination micro-high-performance liquid-chromatography/mass spectrometry

    International Nuclear Information System (INIS)

    Haider, K.

    1997-03-01

    The coupling of liquid chromatography and mass spectrometry is still growing in significance. In this thesis, a particle beam interface has been investigated for combining ion chromatography with mass spectrometric detection. To introduce the eluent directly (without membrane suppressor) into the spectrometer, only methods with low flow rates like microcolumn chromatography can be used. For the preparation of the columns, reversed-phase and silica-based anion exchange materials were packed into PEEK, steel and fused-silica capillaries with i.d. from 130 to 1000 μm using different methods. The performance of the particle beam interface (modified with a new miniaturized aerosol generator) and the mass spectrometric detection has been studied for a series of inorganic anions as well as aminopolycarboxylic acids and the metal-EDTA complexes. Detection limits between 10 and 100 ng injected could be achieved in the multiple ion detection mode of the mass spectrometer for the investigated solutes. A second type of interface, the direct liquid introduction (DLI) has been used to analyze the priority pollutant phenols. This interface is based on a modified GC-interface into the MS. Separation columns used so far include packed fused-silica capillaries with inner diameter of 75 μm and polystyrene-divinylbenzene (functionalized with tert. butyl groups) as stationary phase. Aspects of instrumentation and effects of chemical ionization in the direct liquid introduction mode are discussed. (author)

  8. Detection of argan oil adulteration with vegetable oils by high-performance liquid chromatography-evaporative light scattering detection.

    Science.gov (United States)

    Salghi, Rachid; Armbruster, Wolfgang; Schwack, Wolfgang

    2014-06-15

    Triacylglycerol profiles were selected as indicator of adulteration of argan oils to carry out a rapid screening of samples for the evaluation of authenticity. Triacylglycerols were separated by high-performance liquid chromatography-evaporative light scattering detection. Different peak area ratios were defined to sensitively detect adulteration of argan oil with vegetable oils such as sunflower, soy bean, and olive oil up to the level of 5%. Based on four reference argan oils, mean limits of detection and quantitation were calculated to approximately 0.4% and 1.3%, respectively. Additionally, 19 more argan oil reference samples were analysed by high-performance liquid chromatography-refractive index detection, resulting in highly comparative results. The overall strategy demonstrated a good applicability in practise, and hence a high potential to be transferred to routine laboratories. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses

    OpenAIRE

    Suriyavathana Muthukrishnan; Subha Palanisamy; Senthilkumar Subramanian; Sumathi Selvaraj; Kavitha Rani Mari; Ramalingam Kuppulingam

    2016-01-01

    Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV) were identified by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GC-MS) analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. Th...

  10. Separation of lanthanum from nuclear fuel solutions by high performance liquid chromatography

    International Nuclear Information System (INIS)

    Lazar, G. C.; Petre, M.; Androne, G.; Benga, A.

    2016-01-01

    This paper presents the separation of uranium, praseodymium and lanthanum from nuclear fuel solutions by high performance liquid chromatography (HPLC). The aim of this study is to establish a minimum concentration of lanthanum which can be analyzed by high performance liquid chromatography, and also to study the effect of uranium concentration on the separation of praseodymium and lanthanum. Optimum gradient mode was established for mixture standard stoc solutions with uranium in a concentration of 1 mg/ml, praseodymium and lanthanum in a concentration range of 1-5 μg/ml from each element. These conditions were applied for the separation of lanthanum from a nuclear fuel solution in which praseodymium and lanthanum were added in a concentration of 3 μg/ml from each element. The elution behavior of lanthanum as a function of the pH and the concentration of the mobile phase, using a mixture of 1-octanesulfonic acid sodium salt with a-hidroxyisobutiric acid is presented. (authors)

  11. Integrating qualitative and quantitative characterization of traditional Chinese medicine injection by high-performance liquid chromatography with diode array detection and tandem mass spectrometry.

    Science.gov (United States)

    Xie, Yuan-yuan; Xiao, Xue; Luo, Juan-min; Fu, Chan; Wang, Qiao-wei; Wang, Yi-ming; Liang, Qiong-lin; Luo, Guo-an

    2014-06-01

    The present study aims to describe and exemplify an integrated strategy of the combination of qualitative and quantitative characterization of a multicomponent mixture for the quality control of traditional Chinese medicine injections with the example of Danhong injection (DHI). The standardized chemical profile of DHI has been established based on liquid chromatography with diode array detection. High-performance liquid chromatography coupled with time-of-flight mass spectrometry and high-performance liquid chromatography with electrospray multistage tandem ion-trap mass spectrometry have been developed to identify the major constituents in DHI. The structures of 26 compounds including nucleotides, phenolic acids, and flavonoid glycosides were identified or tentatively characterized. Meanwhile, the simultaneous determination of seven marker constituents, including uridine, adenosine, danshensu, protocatechuic aldehyde, p-coumaric acid, rosmarinic acid, and salvianolic acid B, in DHI was performed by multiwavelength detection based on high-performance liquid chromatography with diode array detection. The integrated qualitative and quantitative characterization strategy provided an effective and reliable pattern for the comprehensive and systematic characterization of the complex traditional Chinese medicine system. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. High-performance liquid chromatography analysis methods developed for quantifying enzymatic esterification of flavonoids in ionic liquids.

    Science.gov (United States)

    Lue, Bena-Marie; Guo, Zheng; Xu, Xuebing

    2008-07-11

    Methods using reversed-phase high-performance liquid chromatography (RP-HPLC) with ELSD were investigated to quantify enzymatic reactions of flavonoids with fatty acids in the presence of diverse room temperature ionic liquids (RTILs). A buffered salt (preferably triethylamine-acetate) was found essential for separation of flavonoids from strongly polar RTILs, whereby RTILs were generally visible as two major peaks identified based on an ion-pairing/exchanging hypothesis. C8 and C12 stationary phases were optimal while mobile phase pH (3-7) had only a minor influence on separation. The method developed was successfully applied for primary screening of RTILs (>20), with in depth evaluation of substrates in 10 RTILs, for their evaluation as reaction media.

  13. Identification, characterization, and high-performance liquid chromatography quantification of process-related impurities in vonoprazan fumarate.

    Science.gov (United States)

    Liu, Lei; Cao, Na; Ma, Xingling; Xiong, Kaihe; Sun, Lili; Zou, Qiaogen

    2016-04-01

    High-performance liquid chromatography analysis of vonoprazan fumarate, a novel proton pump inhibitor drug revealed six impurities. These were identified by liquid chromatography with mass spectrometry. Further, the structures of the impurities were confirmed by synthesis followed by characterization by mass spectrometry, NMR spectroscopy, and infrared spectroscopy. On the basis of these data and knowledge of the synthetic scheme of vonoprazan fumarate, the previously unknown impurity was identified as 1-[5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methyldimethylamine, which is a new compound. The possible mechanisms by which these impurities were formed were also discussed. A high-performance liquid chromatography method was optimized in order to separate, selectively detect, and quantify all process-related impurities of vonoprazan fumarate. The presented method has been validated in terms of linearity, limits of detection, and quantification, and response factors and, therefore, is highly suitable for routine analysis of vonoprazan fumarate related substances as well as stability studies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. High-performance liquid chromatography separation of unsaturated organic compounds by a monolithic silica column embedded with silver nanoparticles.

    Science.gov (United States)

    Zhu, Yang; Morisato, Kei; Hasegawa, George; Moitra, Nirmalya; Kiyomura, Tsutomu; Kurata, Hiroki; Kanamori, Kazuyoshi; Nakanishi, Kazuki

    2015-08-01

    The optimization of a porous structure to ensure good separation performances is always a significant issue in high-performance liquid chromatography column design. Recently we reported the homogeneous embedment of Ag nanoparticles in periodic mesoporous silica monolith and the application of such Ag nanoparticles embedded silica monolith for the high-performance liquid chromatography separation of polyaromatic hydrocarbons. However, the separation performance remains to be improved and the retention mechanism as compared with the Ag ion high-performance liquid chromatography technique still needs to be clarified. In this research, Ag nanoparticles were introduced into a macro/mesoporous silica monolith with optimized pore parameters for high-performance liquid chromatography separations. Baseline separation of benzene, naphthalene, anthracene, and pyrene was achieved with the theoretical plate number for analyte naphthalene as 36,000 m(-1). Its separation function was further extended to cis/trans isomers of aromatic compounds where cis/trans stilbenes were chosen as a benchmark. Good separation of cis/trans-stilbene with separation factor as 7 and theoretical plate number as 76,000 m(-1) for cis-stilbene was obtained. The trans isomer, however, is retained more strongly, which contradicts the long- established retention rule of Ag ion chromatography. Such behavior of Ag nanoparticles embedded in a silica column can be attributed to the differences in the molecular geometric configuration of cis/trans stilbenes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Resolution of the stereoisomers of baclofen by high performance liquid chromatography

    International Nuclear Information System (INIS)

    Weatherby, R.P.; Allan, R.D.; Johnston, G.A.R.

    1984-01-01

    The GABA analogue baclofen [3-(p-chlorophenyl)-4-aminobutanoic acid] has stereospecific actions on the peripheral and central nervous systems. This paper describes the resolution of tritium-labelled baclofen by high performance liquid chromatography on a reverse-phase C18 column using a chiral mobile phase. The method, which may have general application to certain other GABA analogues, affords optically pure (+)- and (-)-baclofen labelled with tritium to high specific activity suitable for ligand binding and other neurochemical studies. (Auth.)

  16. Chemical fingerprint of Ganmaoling granule by double-wavelength ultra high performance liquid chromatography and ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Lou, Qiong; Ye, Xiaolan; Zhou, Yingyi; Li, Hua; Song, Fenyun

    2015-06-01

    A method incorporating double-wavelength ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry was developed for the investigation of the chemical fingerprint of Ganmaoling granule. The chromatographic separations were performed on an ACQUITY UPLC HSS C18 column (2.1 × 50 mm, 1.8 μm) at 30°C using gradient elution with water/formic acid (1%) and acetonitrile at a flow rate of 0.4 mL/min. A total of 11 chemical constituents of Ganmaoling granule were identified from their molecular weight, UV spectra, tandem mass spectrometry data, and retention behavior by comparing the results with those of the reference standards or literature. And 25 peaks were selected as the common peaks for fingerprint analysis to evaluate the similarities among 25 batches of Ganmaoling granule. The results of principal component analysis and orthogonal projection to latent structures discriminant analysis showed that the important chemical markers that could distinguish the different batches were revealed as 4,5-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 4-O-caffeoylquinic acid. This is the first report of the ultra high performance liquid chromatography chemical fingerprint and component identification of Ganmaoling granule, which could lay a foundation for further studies of Ganmaoling granule. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Stationary and through-flow radiochemical detectors in cooperation with high performance liquid chromatography: Application in biochemistry

    International Nuclear Information System (INIS)

    Kehr, J.

    1986-01-01

    A review article is presented containing some original experimental data and discussing the usability of radiochemical detection of labelled compounds using high performance liquid chromatography. The stationary and through-flow types of detection are compared with respect to efficiency, chromatographic zone resolution, usability in biochemical research, and also to the current trends of development of liquid chromatography. (author). 3 figs., 1 tab., 19 refs

  18. Simultaneous Determination of Four Preservatives in Foodstuffs by High Performance Liquid Chromatography

    OpenAIRE

    Mohammad Faraji; Farzaneh Rahbarzare

    2016-01-01

    Background and objectives:  High concentration of preservatives in food may result in gastrointestinal disturbances whereby some patients suffering from asthma, rhinitis, or urticaria. The aim of this study is the introduction and optimization a new method for simultaneous determination of four preservatives (SB, PS, MP, PP) in foodstuff by high performance liquid chromatography. Materials and methods: Important factors in extraction, separation and determination process were optimiz...

  19. Core-Shell Columns in High-Performance Liquid Chromatography: Food Analysis Applications

    OpenAIRE

    Preti, Raffaella

    2016-01-01

    The increased separation efficiency provided by the new technology of column packed with core-shell particles in high-performance liquid chromatography (HPLC) has resulted in their widespread diffusion in several analytical fields: from pharmaceutical, biological, environmental, and toxicological. The present paper presents their most recent applications in food analysis. Their use has proved to be particularly advantageous for the determination of compounds at trace levels or when a large am...

  20. Low Density Solvent-Based Dispersive Liquid-Liquid Microextraction for the Determination of Synthetic Antioxidants in Beverages by High-Performance Liquid Chromatography

    Science.gov (United States)

    Çabuk, Hasan; Köktürk, Mustafa

    2013-01-01

    A simple and efficient method was established for the determination of synthetic antioxidants in beverages by using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography with ultraviolet detection. Butylated hydroxy toluene, butylated hydroxy anisole, and tert-butylhydroquinone were the antioxidants evaluated. Experimental parameters including extraction solvent, dispersive solvent, pH of sample solution, salt concentration, and extraction time were optimized. Under optimal conditions, the extraction recoveries ranged from 53 to 96%. Good linearity was observed by the square of correlation coefficients ranging from 0.9975 to 0.9997. The relative standard deviations ranged from 1.0 to 5.2% for all of the analytes. Limits of detection ranged from 0.85 to 2.73 ng mL−1. The method was successfully applied for determination of synthetic antioxidants in undiluted beverage samples with satisfactory recoveries. PMID:23853535

  1. Low Density Solvent-Based Dispersive Liquid-Liquid Microextraction for the Determination of Synthetic Antioxidants in Beverages by High-Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Hasan Çabuk

    2013-01-01

    Full Text Available A simple and efficient method was established for the determination of synthetic antioxidants in beverages by using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography with ultraviolet detection. Butylated hydroxy toluene, butylated hydroxy anisole, and tert-butylhydroquinone were the antioxidants evaluated. Experimental parameters including extraction solvent, dispersive solvent, pH of sample solution, salt concentration, and extraction time were optimized. Under optimal conditions, the extraction recoveries ranged from 53 to 96%. Good linearity was observed by the square of correlation coefficients ranging from 0.9975 to 0.9997. The relative standard deviations ranged from 1.0 to 5.2% for all of the analytes. Limits of detection ranged from 0.85 to 2.73 ng mL−1. The method was successfully applied for determination of synthetic antioxidants in undiluted beverage samples with satisfactory recoveries.

  2. Sugar Determination in Foods with a Radially Compressed High Performance Liquid Chromatography Column.

    Science.gov (United States)

    Ondrus, Martin G.; And Others

    1983-01-01

    Advocates use of Waters Associates Radial Compression Separation System for high performance liquid chromatography. Discusses instrumentation and reagents, outlining procedure for analyzing various foods and discussing typical student data. Points out potential problems due to impurities and pump seal life. Suggests use of ribose as internal…

  3. Experimental hydrophobicity parameters of perfluorinated alkylated substances from reversed-phase high performance liquid chromatography

    NARCIS (Netherlands)

    de Voogt, P.; Zurano, L.; Serné, P.; Haftka, J.J.H.

    2012-01-01

    Capacity factors of perfluorinated alkylated substances were obtained from isocratic reversed-phase high-performance liquid chromatography-mass spectrometry experiments at different organic modifier strengths of the mobile phase. The resulting capacity factor v. modifier strengths plots were

  4. Analysis of the Constituents in “Zhu She Yong Xue Shuan Tong” by Ultra High Performance Liquid Chromatography with Quadrupole Time-of-Flight Mass Spectrometry Combined with Preparative High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Lin-Lin Wang

    2015-11-01

    Full Text Available “Zhu She Yong Xue Shuan Tong” lyophilized powder (ZSYXST, consists of a series of saponins extracted from Panax notoginseng, which has been widely used in China for the treatment of strokes. In this study, an ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS combined with preparative high performance liquid chromatography (PHPLC method was developed to rapidly identify both major and minor saponins in ZSYXST. Some high content components were removed through PHPLC in order to increase the sensitivity of the trace saponins. Then, specific characteristic fragment ions in both positive and negative mode were utilized to determine the types of aglycone, saccharide, as well as the saccharide chain linkages. As a result, 94 saponins, including 20 pairs of isomers and ten new compounds, which could represent higher than 98% components in ZSYXST, were identified or tentatively identified in commercial ZSYXST samples.

  5. Enantiomeric high-performance liquid chromatography resolution and absolute configuration of 6β-benzoyloxy-3α-tropanol.

    Science.gov (United States)

    Muñoz, Marcelo A; González, Natalia; Joseph-Nathan, Pedro

    2016-07-01

    The absolute configuration of the naturally occurring isomers of 6β-benzoyloxy-3α-tropanol (1) has been established by the combined use of chiral high-performance liquid chromatography with electronic circular dichroism detection and optical rotation detection. For this purpose (±)-1, prepared in two steps from racemic 6-hydroxytropinone (4), was subjected to chiral high-performance liquid chromatography with electronic circular dichroism and optical rotation detection allowing the online measurement of both chiroptical properties for each enantiomer, which in turn were compared with the corresponding values obtained from density functional theory calculations. In an independent approach, preparative high-performance liquid chromatography separation using an automatic fraction collector, yielded an enantiopure sample of OR (+)-1 whose vibrational circular dichroism spectrum allowed its absolute configuration assignment when the bands in the 1100-950 cm(-1) region were compared with those of the enantiomers of esters derived from 3α,6β-tropanediol. In addition, an enantiomerically enriched sample of 4, instead of OR (±)-4, was used for the same transformation sequence, whose high-performance liquid chromatography follow-up allowed their spectroscopic correlation. All evidences lead to the OR (+)-(1S,3R,5S,6R) and OR (-)-(1R,3S,5R,6S) absolute configurations, from where it follows that samples of 1 isolated from Knightia strobilina and Erythroxylum zambesiacum have the OR (+)-(1S,3R,5S,6R) absolute configuration, while the sample obtained from E. rotundifolium has the OR (-)-(1R,3S,5R,6S) absolute configuration. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Quantitative analysis of phylloquinone (vitamin K1) in soy bean oils by high-performance liquid chromatography.

    Science.gov (United States)

    Zonta, F; Stancher, B

    1985-07-19

    A high-performance liquid chromatographic method for determining phylloquinone (vitamin K1) in soy bean oils is described. Resolution of vitamin K1 from interfering peaks of the matrix was obtained after enzymatic digestion, extraction and liquid-solid chromatography on alumina. An isocratic reversed-phase chromatography with UV detection was used in the final stage. The quantitation was carried out by the standard addition method, and the recovery of the whole procedure was 88.2%.

  7. UHPLC: The Greening Face of Liquid Chromatography

    OpenAIRE

    Cielecka-Piontek, Judyta; Zalewski, Przemys?aw; Jeli?ska, Anna; Garbacki, Piotr

    2013-01-01

    Pharmaceutical analysis based on chromatographic separation is an important part of studies aimed at developing routine quality analysis of drugs. High-performance liquid chromatography (HPLC) is one of the main analytical techniques recommended for drug analysis. Although it meets many criteria vital for analysis, it is time-consuming and uses a relatively high amount of organic solvents compared to other analytical techniques. Recently, Ultra-high-performance liquid chromatography (UHPLC) h...

  8. 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…

  9. Improved assay for thymine base damage in E. coli using high performance liquid chromatography

    International Nuclear Information System (INIS)

    Claycamp, H.G.

    1985-01-01

    A simple high performance liquid chromatography (HPLC) technique has been established for the simultaneous assay of thymine and thymidine radiation damage products. The HPLC procedure uses an isocratic mobile phase of 4% acetonitrile in 0.2 M ammonium dihydrogen phosphate (pH 5.0), a reversed-phase octadecylsilicate (5 micro-spherical packing) 0.45 x 25 cm column, and a variable wavelength UV detector. This procedure affords much better resolution than other published procedures that use 10 micron columns or separate assays for bases and nucleosides. For example, irradiation of 5 x 10 -3 M thymidine solutions have been performed to calibrate the system for base damage assays in E. coli. This yields up to 15 resolvable residues within 20 minutes. Sensitivity of the system (at 2210 nm) for 5,6- dihydrothymine (DHT) is about 10 -10 moles. Preliminary results show that this translates to about 0.4 DHT residues per 10 6 daltons of E. coli DNA. This is comparable to the sensitivities of monoclonal assays to thymine damage products that have recently been reported by others. Since it is feasible that the sensitivity of this system can be improved by 2-3 times, this HPLC technique should provide a simple and rapid means of detecting E. coli base damage release and base damage in nucleoside hydrolysates of DNA

  10. High-performance liquid chromatography of rat and mouse islet polypeptides

    DEFF Research Database (Denmark)

    Linde, S; Hansen, B; Welinder, B S

    1990-01-01

    After preparative high-performance liquid chromatography of mouse islet culture medium, concentrated on disposable C18 cartridges (Sep-Pak), an unexpected insulin immunoreactive peak eluting earlier than mouse insulin I and II was detected. Molecular mass determination by mass spectrometry...... on the buffer, the organic modifier and the procedure. In particular the use of methanol-trifluoroacetic acid resulted in extensive oxidation. The oxidation could be minimized by adding 2 mM dithiothreitol to the buffer and by degassing and/or nitrogen-bubbling of the buffer. Minimal formation of Met...

  11. Denaturing high-performance liquid chromatography mutation analysis in patients with reduced Protein S levels

    DEFF Research Database (Denmark)

    Bathum, Lise; Münster, Anna-Marie; Nybo, Mads

    2008-01-01

    diagnosis and risk estimation. The aim was to design a high-throughput genetic analysis based on denaturing high-performance liquid chromatography to identify sequence variations in the gene coding for Protein S. PATIENTS: In total, 55 patients referred to the Section of Thrombosis and Haemostasis, Odense......BACKGROUND: Patients with congenital Protein S deficiency have increased risk of venous thromboembolism. However, Protein S levels show large intra-individual variation and the biochemical assays have low accuracy and a high interlaboratory variability. Genetic analysis might aid in a more precise......, giving a precise diagnosis and subsequently a better risk estimation....

  12. Characterization of Extracellular Vesicles by Size-Exclusion High-Performance Liquid Chromatography (HPLC).

    Science.gov (United States)

    Huang, Tao; He, Jiang

    2017-01-01

    Extracellular vesicles (EVs) have recently attracted substantial attention due to the potential diagnostic and therapeutic relevance. Although a variety of techniques have been used to isolate and analyze EVs, it is still far away from satisfaction. Size-exclusion chromatography (SEC), which separates subjects by size, has been widely applied in protein purification and analysis. The purpose of this chapter is to show the applications of size-exclusion high-performance liquid chromatography (HPLC) as methods for EV characterization of impurities or contaminants of small size, and thus for quality assay for the purity of the samples of EVs.

  13. Highly sensitive assay for tyrosine hydroxylase activity by high-performance liquid chromatography.

    Science.gov (United States)

    Nagatsu, T; Oka, K; Kato, T

    1979-07-21

    A highly sensitive assay for tyrosine hydroxylase (TH) activity by high-performance liquid chromatography (HPLC) with amperometric detection was devised based on the rapid isolation of enzymatically formed DOPA by a double-column procedure, the columns fitted together sequentially (the top column of Amberlite CG-50 and the bottom column of aluminium oxide). DOPA was adsorbed on the second aluminium oxide column, then eluted with 0.5 M hydrochloric acid, and assayed by HPLC with amperometric detection. D-Tyrosine was used for the control. alpha-Methyldopa was added to the incubation mixture as an internal standard after incubation. This assay was more sensitive than radioassays and 5 pmol of DOPA formed enzymatically could be measured in the presence of saturating concentrations of tyrosine and 6-methyltetrahydropterin. The TH activity in 2 mg of human putamen could be easily measured, and this method was found to be particularly suitable for the assay of TH activity in a small number of nuclei from animal and human brain.

  14. Hb A1c Separation by High Performance Liquid Chromatography in Hemoglobinopathies

    Directory of Open Access Journals (Sweden)

    Vani Chandrashekar

    2016-01-01

    Full Text Available Hb A1c measurement is subject to interference by hemoglobin traits and this is dependent on the method used for determination. In this paper we studied the difference between Hb A1c measured by HPLC in hemoglobin traits and normal chromatograms. We also studied the correlation of Hb A1c with age. Hemoglobin analysis was carried out by high performance liquid chromatography. Spearman’s rank correlation was used to study correlation between A1c levels and age. Mann-Whitney U test was used to study the difference in Hb A1c between patients with normal hemoglobin and hemoglobin traits. A total of 431 patients were studied. There was positive correlation with age in patients with normal chromatograms only. No correlation was seen in Hb E trait or beta thalassemia trait. No significant difference in Hb A1c of patients with normal chromatograms and patients with hemoglobin traits was seen. There is no interference by abnormal hemoglobin in the detection of A1c by high performance liquid chromatography. This method cannot be used for detection of A1c in compound heterozygous and homozygous disorders.

  15. Determination of citrus limonoid glucosides by high performance liquid chromatography coupled to post-column reaction with Ehrlich’s Reagent

    Science.gov (United States)

    A method for the identification and quantification of citrus limonoid glucosides in juices based upon high performance liquid chromatography (HPLC) separation coupled to post-column reaction with Ehrlichs’s reagent has been developed. This method utilizes a phenyl stationary phase and an isocratic ...

  16. Simultaneous determination of several phytohormones in natural coconut juice by hollow fiber-based liquid-liquid-liquid microextraction-high performance liquid chromatography.

    Science.gov (United States)

    Wu, Yunli; Hu, Bin

    2009-11-06

    A simple, selective, sensitive and inexpensive method of hollow fiber-based liquid-liquid-liquid microextraction (HF-LLLME) combined with high performance liquid chromatography (HPLC)-ultraviolet (UV) detection was developed for the determination of four acidic phytohormones (salicylic acid (SA), indole-3-acetic acid (IAA), (+/-) abscisic acid (ABA) and (+/-) jasmonic acid (JA)) in natural coconut juice. To the best of our knowledge, this is the first report on the use of liquid phase microextraction (LPME) as a sample pretreatment technique for the simultaneous analysis of several phytohormones. Using phenetole to fill the pores of hollow fiber as the organic phase, 0.1molL(-1) NaOH solution in the lumen of hollow fiber as the acceptor phase and 1molL(-1) HCl as the donor phase, a simultaneous preconcentration of four target phytohormones was realized. The acceptor phase was finally withdrawn into the microsyringe and directly injected into HPLC for the separation and quantification of the target phytohormones. The factors affecting the extraction efficiency of four phytohormones by HF-LLLME were optimized with orthogonal design experiment, and the data was analyzed by Statistical Product and Service Solutions (SPSS) software. Under the optimized conditions, the enrichment factors for SA, IAA, ABA and JA were 243, 215, 52 and 48, with the detection limits (S/N=3) of 4.6, 1.3, 0.9ngmL(-1) and 8.8 microg mL(-1), respectively. The relative standard deviations (RSDs, n=7) were 7.9, 4.9, 6.8% at 50ngmL(-1) level for SA, IAA, ABA and 8.4% at 500 microg mL(-1) for JA, respectively. To evaluate the accuracy of the method, the developed method was applied for the simultaneous analysis of several phytohormones in five natural coconut juice samples, and the recoveries for the spiked samples were in the range of 88.3-119.1%.

  17. tRNA separation by high-performance liquid chromatography using an aggregate of ODS-Hypersil and trioctylmethylammonium chloride

    NARCIS (Netherlands)

    Bischoff, Rainer; Graeser, E.; Mclaughlin, L.W.

    1983-01-01

    High-performance liquid chromatography on a reversed-phase support treated with a tetraalkylammonium salt was used to separate tRNAs from baker's yeast. While resolution by this column appears to result from both anion-exchange and reversed-phase chromatography, it is the hydrophobic interactions

  18. An on-line high performance liquid chromatography-crocin bleaching assay for detection of antioxidants

    NARCIS (Netherlands)

    Bountagkidou, O.; Klift, van der E.J.C.; Tsimidou, M.Z.; Ordoudi, S.A.; Beek, van T.A.

    2012-01-01

    An on-line HPLC (high performance liquid chromatography) method for the rapid screening of individual antioxidants in mixtures was developed using crocin as a substrate (i.e. oxidation probe) and 2,2'-azobis(2-amidinopropane dihydrochloride (AAPH)) in phosphate buffer (pH 7.5) as a radical

  19. Separation of four flavonol glycosides from Solanum rostratum Dunal using aqueous two-phase flotation followed by preparative high-performance liquid chromatography.

    Science.gov (United States)

    Chang, Lin; Shao, Qian; Xi, Xingjun; Chu, Qiao; Wei, Yun

    2017-02-01

    Aqueous two-phase flotation followed by preparative high-performance liquid chromatography was used to separate four flavonol glycosides from Solanum rostratum Dunal. In the aqueous two-phase flotation section, the effects of sublation solvent, solution pH, (NH 4 ) 2 SO 4 concentration in aqueous solution, cosolvent, N 2 flow rate, flotation time, and volumes of the polyethylene glycol phase on the recovery were investigated in detail, and the optimal conditions were selected: 50 wt% polyethylene glycol 1000 ethanol solvent as the flotation solvent, pH 4, 350 g/L of (NH 4 ) 2 SO 4 concentration in aqueous phase, 40 mL/min of N 2 flow rate, 30 min of flotation time, 10.0 mL of flotation solvent volume, and two times. After aqueous two-phase flotation concentration, the flotation products were purified by preparative high-performance liquid chromatography. The purities of the final products A and B were 98.1 and 99.0%. Product B was the mixture of three compounds based on the analysis of high-performance liquid chromatography at the temperature of 10°C, while product A was hyperoside after the identification by nuclear magnetic resonance. Astragalin, 3'-O-methylquercetin 3-O-β-d-galactopyranoside, and 3'-O-methylquercetin 3-O-β-d-glucopyranoside were obtained with the purity of 93.8, 97.1, and 99.2%, respectively, after the further separation of product B using preparative high-performance liquid chromatography. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Versatile ligands for high-performance liquid chromatography: An overview of ionic liquid-functionalized stationary phases.

    Science.gov (United States)

    Zhang, Mingliang; Mallik, Abul K; Takafuji, Makoto; Ihara, Hirotaka; Qiu, Hongdeng

    2015-08-05

    Ionic liquids (ILs), a class of unique substances composed purely by cation and anions, are renowned for their fascinating physical and chemical properties, such as negligible volatility, high dissolution power, high thermal stability, tunable structure and miscibility. They are enjoying ever-growing applications in a great diversity of disciplines. IL-modified silica, transforming the merits of ILs into chromatographic advantages, has endowed the development of high-performance liquid chromatography (HPLC) stationary phase with considerable vitality. In the last decade, IL-functionalized silica stationary phases have evolved into a series of branches to accommodate to different HPLC modes. An up-to-date overview of IL-immobilized stationary phases is presented in this review, and divided into five parts according to application mode, i.e., ion-exchange, normal-phase, reversed-phase, hydrophilic interaction and chiral recognition. Specific attention is channeled to synthetic strategies, chromatographic behavior and separation performance of IL-functionalized silica stationary phases. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Recent advances in ultra-high performance liquid chromatography for the analysis of traditional chinese medicine

    Science.gov (United States)

    Traditional Chinese medicines (TCMs) have been widely used for the prevention and treatment of various diseases for thousands of years in China. Ultra Performance Liquid Chromatography (UHPLC) is a relatively new technique offering new possibilities in liquid chromatography. This paper reviews recen...

  2. Simultaneous Determination of Eight Bioactive Compounds in Dianthus superbus by High-performance Liquid Chromatography.

    Science.gov (United States)

    Yun, Bo-Ra; Yang, Hye Jin; Weon, Jin Bae; Lee, Jiwoo; Eom, Min Rye; Ma, Choong Je

    2016-05-01

    Dianthus superbus, one of traditional herbal medicine, is widely used to treat urethritis, carbuncles and carcinoma. A simultaneous determination method was established for controlling the quality of D. superbus using the eight compounds, (E)-methyl-4-hydroxy-4-(8a-methyl-3-oxodecahydronaphthalen-4a-yl) (1), diosmetin-7-O(2'',6''-di-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside (2), vanillic acid (3), 4-hydroxyphenyl acetic acid (4), 4-methoxyphenyl acetic acid (5), (E)-4-methoxycinnamic acid (6), 3-methoxy-4-hydroxyphenylethanol (7), and methyl hydroferulate (8) isolated from D. superbus. This analysis method was developed using high performance liquid chromatography coupled with diode array detector with a Shishedo C18 column at a column temperature of 3°C. The mobile phase was composed of 0.1% trifluoroacetic acid in water and acetonitrile. The flow rate was 1 ml/min and detection wavelength was set at 205 nm and 280 nm. Validation was performed in order to demonstrate selectivity, accuracy and precision of the method. The calibration curves showed good linearity (R (2) > 0.99). The limits of detection and limits of quantification were within the ranges 0.0159-0.6205 μg/ml and 0.3210-1.8802 μg/ml, respectively. Moreover, the relative standard deviations of intra- and inter-day precision were both Dianthus superbus was established by high performance liquid chromatography-diode array detectorDeveloped analysis method is validated with linearity, precious and accuracyThe newly established method was successfully evaluated contents of eight compounds in 12 D. superbus samples (D.1.D.12) from various regions and compared. Abbreviations used: HPLC: High performance liquid chromatography, LOD: Limits of detection, LOQ: Limits of quantification, RSD: Relative standard deviation.

  3. A high-performance liquid chromatography-based radiometric assay for sucrose-phosphate synthase and other UDP-glucose requiring enzymes

    International Nuclear Information System (INIS)

    Salvucci, M.E.; Crafts-Brandner, S.J.

    1991-01-01

    A method for product analysis that eliminates a problematic step in the radiometric sucrose-phosphate synthase assay is described. The method uses chromatography on a boronate-derivatized high-performance liquid chromatography column to separate the labeled product, [14C]sucrose phosphate, from unreacted uridine 5'-diphosphate-[14C]glucose (UDP-Glc). Direct separation of these compounds eliminates the need for treatment of the reaction mixtures with alkaline phosphatase, thereby avoiding the problem of high background caused by contaminating phosphodiesterase activity in alkaline phosphatase preparations. The method presented in this paper can be applied to many UDP-Glc requiring enzymes; here the authors show its use for determining the activities of sucrose-phosphate synthase, sucrose synthase, and uridine diphosphate-glucose pyrophosphorylase in plant extracts

  4. Determination of sunset yellow and tartrazine in food samples by combining ionic liquid-based aqueous two-phase system with high performance liquid chromatography.

    Science.gov (United States)

    Sha, Ou; Zhu, Xiashi; Feng, Yanli; Ma, Weixing

    2014-01-01

    We proposed a simple and effective method, by coupling ionic liquid-based aqueous two-phase systems (IL-ATPSs) with high performance liquid chromatography (HPLC), for the analysis of determining tartrazine and sunset yellow in food samples. Under the optimized conditions, IL-ATPSs generated an extraction efficiency of 99% for both analytes, which could then be directly analyzed by HPLC without further treatment. Calibration plots were linear in the range of 0.01-50.0 μg/mL for both Ta and SY. The limits of detection were 5.2 ng/mL for Ta and 6.9 ng/mL for SY. This method proves successful for the separation/analysis of tartrazine and sunset yellow in soft drink sample, candy sample, and instant powder drink and leads to consistent results as obtained from the Chinese national standard method.

  5. Improved method for the determination of the cortisol production rate using high-performance liquid chromatography and liquid scintillation counting

    NARCIS (Netherlands)

    van Ingen, H. E.; Endert, E.

    1988-01-01

    Two new methods for the determination of the cortisol production rate using reversed-phase high-performance liquid chromatography are described. One uses ultraviolet detection at 205 nm, the other on-line post-column derivatization with benzamidine, followed by fluorimetric detection. The specific

  6. Simultaneous Analysis of Ursolic Acid and Oleanolic Acid in Guava Leaves Using QuEChERS-Based Extraction Followed by High-Performance Liquid Chromatography

    OpenAIRE

    Xu, Chang; Liao, Yiyi; Fang, Chunyan; Tsunoda, Makoto; Zhang, Yingxia; Song, Yanting; Deng, Shiming

    2017-01-01

    In this paper, a novel method of QuEChERS-based extraction coupled with high-performance liquid chromatography has been developed for the simultaneous determination of ursolic acid (UA) and oleanolic acid (OA) in guava leaves. The QuEChERS-based extraction parameters, including the amount of added salt, vortex-assisted extraction time, and absorbent amount, and the chromatographic conditions were investigated for the analysis of UA and OA in guava leaves. Under the optimized conditions, the m...

  7. A simple, rapid and validated high-performance liquid chromatography method suitable for clinical measurements of human mercaptalbumin and non-mercaptalbumin.

    Science.gov (United States)

    Yasukawa, Keiko; Shimosawa, Tatsuo; Okubo, Shigeo; Yatomi, Yutaka

    2018-01-01

    Background Human mercaptalbumin and human non-mercaptalbumin have been reported as markers for various pathological conditions, such as kidney and liver diseases. These markers play important roles in redox regulations throughout the body. Despite the recognition of these markers in various pathophysiologic conditions, the measurements of human mercaptalbumin and non-mercaptalbumin have not been popular because of the technical complexity and long measurement time of conventional methods. Methods Based on previous reports, we explored the optimal analytical conditions for a high-performance liquid chromatography method using an anion-exchange column packed with a hydrophilic polyvinyl alcohol gel. The method was then validated using performance tests as well as measurements of various patients' serum samples. Results We successfully established a reliable high-performance liquid chromatography method with an analytical time of only 12 min per test. The repeatability (within-day variability) and reproducibility (day-to-day variability) were 0.30% and 0.27% (CV), respectively. A very good correlation was obtained with the results of the conventional method. Conclusions A practical method for the clinical measurement of human mercaptalbumin and non-mercaptalbumin was established. This high-performance liquid chromatography method is expected to be a powerful tool enabling the expansion of clinical usefulness and ensuring the elucidation of the roles of albumin in redox reactions throughout the human body.

  8. Analysis of lignans in Magnoliae Flos by turbulent flow chromatography with online solid-phase extraction and high-performance liquid chromatography with tandem mass spectrometry.

    Science.gov (United States)

    Zhou, Xuan; Chen, Cen; Ye, Xiaolan; Song, Fenyun; Fan, Guorong; Wu, Fuhai

    2016-04-01

    In this study, a method coupling turbulent flow chromatography with online solid-phase extraction and high-performance liquid chromatography with tandem mass spectrometry was developed for analyzing the lignans in Magnoliae Flos. By the online pretreatment of turbulent flow chromatography solid-phase extraction, the impurities removal and analytes concentration were automatically processed, and the lignans were separated rapidly and well. Seven lignans of Magnoliae Flos including epieudesmin, magnolin, 1-irioresinol-B-dimethyl ether, epi-magnolin, fargesin aschantin, and demethoxyaschantin were identified by comparing their retention behavior, UV spectra, and mass spectra with those of reference substances or literature data. The developed method was validated, and the good results showed that the method was not only automatic and rapid, but also accurate and reliable. The turbulent flow chromatography with online solid-phase extraction and high-performance liquid chromatography with tandem mass spectrometry method holds a high potential to become an effective method for the quality control of lignans in Magnoliae Flos and a useful tool for the analysis of other complex mixtures. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Serum Protein Profile Study of Clinical Samples Using High Performance Liquid Chromatography-Laser Induced Fluorescence

    DEFF Research Database (Denmark)

    Karemore, Gopal Raghunath; Ukendt, Sujatha; Rai, Lavanya

    2009-01-01

    The serum protein profiles of normal subjects, patients diagnosed with cervical cancer, and oral cancer were recorded using High Performance Liquid Chromatography combined with Laser Induced Fluorescence detection (HPLC-LIF). Serum protein profiles of the above three classes were tested for estab...

  10. DETERMINATION OF CHLOROPHEONIS, NITROPHENOIS AND METHYLPHENOIS IN GROUND-WATER SAMPLES USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

    Science.gov (United States)

    A high performance liquid chromatography (HPLC) method was developed to quantitatively determine phenolic compounds and their isomers in aqueous samples. The HPLC method can analyze a mixture of 15 contaminants in the same analytical run with an analysis time of 25 minutes. The...

  11. DETERMINATION OF CHLOROPHENOLS, NITROPHENOLS, AND METHYLPHENOLS IN GROUND-WATER SAMPLES USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

    Science.gov (United States)

    A high performance liquid chromatography (HPLC) method was developed to quantitatively determine phenolic compounds and their isomers in aqueous samples. The HPLC method can analyze a mixture of 15 contaminants in the same analytical run with an analysis time of 25 minutes. The...

  12. High-performance liquid chromatography determination of dapsone, monoacetyldapsone, and pyrimethamine in filter paper blood spots

    DEFF Research Database (Denmark)

    Rønn, A M; Lemnge, M M; Angelo, H R

    1995-01-01

    A high-performance liquid chromatography method for the simultaneous analysis of dapsone (DDS), the major metabolite of DDS, monoacetyldapsone (MADDS), and pyrimethamine (PYR) was modified for capillary blood samples obtained by finger prick and dried on filter paper. Limit of quantitation using...

  13. Identification of chemical components in Baidianling Capsule based on gas chromatography-mass spectrometry and high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Wu, Wenying; Chen, Yu; Wang, Binjie; Sun, Xiaoyang; Guo, Ping; Chen, Xiaohui

    2017-08-01

    Baidianling Capsule, which is made from 16 Chinese herbs, has been widely used for treating vitiligo clinically. In this study, the sensitive and rapid method has been developed for the analysis of chemical components in Baidianling Capsule by gas chromatography-mass spectrometry in combination with retention indices and high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry. Firstly, a total of 110 potential volatile compounds obtained from different extraction procedures including alkanes, alkenes, alkynes, ketones, ethers, aldehydes, alcohols, phenols, organic acids, esters, furans, pyrrole, acid amides, heterocycles, and oxides were detected from Baidianling Capsule by gas chromatography-mass spectrometry, of which 75 were identified by mass spectrometry in combination with the retention index. Then, a total of 124 components were tentatively identified by high-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry. Fifteen constituents from Baidianling Capsule were accurately identified by comparing the retention times with those of reference compounds, others were identified by comparing the retention times and mass spectrometry data, as well as retrieving the reference literature. This study provides a practical strategy for rapidly screening and identifying the multiple constituents of a complex traditional Chinese medicine. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Crosslinked polymeric ionic liquids as solid-phase microextraction sorbent coatings for high performance liquid chromatography.

    Science.gov (United States)

    Yu, Honglian; Merib, Josias; Anderson, Jared L

    2016-03-18

    Neat crosslinked polymeric ionic liquid (PIL) sorbent coatings for solid-phase microextraction (SPME) compatible with high-performance liquid chromatography (HPLC) are reported for the first time. Six structurally different PILs were crosslinked to nitinol supports and applied for the determination of select pharmaceutical drugs, phenolics, and insecticides. Sampling conditions including sample solution pH, extraction time, desorption solvent, desorption time, and desorption solvent volume were optimized using design of experiment (DOE). The developed PIL sorbent coatings were stable when performing extractions under acidic pH and remained intact in various organic desorption solvents (i.e., methanol, acetonitrile, acetone). The PIL-based sorbent coating polymerized from the IL monomer 1-vinyl-3-(10-hydroxydecyl) imidazolium chloride [VC10OHIM][Cl] and IL crosslinker 1,12-di(3-vinylbenzylimidazolium) dodecane dichloride [(VBIM)2C12] 2[Cl] exhibited superior extraction performance compared to the other studied PILs. The extraction efficiency of pharmaceutical drugs and phenolics increased when the film thickness of the PIL-based sorbent coating was increased while many insecticides were largely unaffected. Satisfactory analytical performance was obtained with limits of detection (LODs) ranging from 0.2 to 2 μg L(-1) for the target analytes. The accuracy of the analytical method was examined by studying the relative recovery of analytes in real water samples, including tap water and lake water, with recoveries varying from 50.2% to 115.9% and from 48.8% to 116.6%, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Nitrate and nitrite content in bottled beverages by ion-pair high-performance liquid chromatography.

    Science.gov (United States)

    Song, Yang; Deng, Gui-Fang; Xu, Xiang-Rong; Chen, Yong-Hong; Chen, Feng; Li, Hua-Bin

    2013-01-01

    Nitrate and nitrite levels in six types of beverages--total of 292 individual samples from 73 brands (four bottles each)--from Guangzhou city in China were evaluated by ion-pair high-performance liquid chromatography. All samples contained nitrate. Nitrate and nitrite ranges were 0.43-46.08 and safety of Chinese bottled beverages.

  16. Enantioselective analysis of drugs: contributions of high-performance liquid chromatography and capillary electrophoresis

    OpenAIRE

    Bonato, Pierina Sueli; Jabor, Valquíria Aparecida Polisel; Gaitani, Cristiane Masetto de

    2005-01-01

    The demand for analytical methods suitable for accurate and reproducible determination of drug enantiomers has increased significantly in the last years. High-performance liquid chromatography (HPLC) using chiral stationary phases and capillary electrophoresis (CE) are the most important techniques used for this purpose. In this paper, the fundamental aspects of chiral separations using both techniques are presented. Some important aspects for the development of enantioselective methods, part...

  17. Theoretical aspects of gradient reversed-phase high performance liquid chromatography of styrene-butylacrylate block copolymers

    NARCIS (Netherlands)

    Kolarova, L.; Jandera, P.; Vonk, E.C.; Claessens, H.A.

    2004-01-01

    Butylacrylate – styrene co-polymers prepared by atom transfer radical polymeratization were separated on an octadecyl silica column by gradient elution with tetrahydrofuran in water, up to the molar masses 10,000. In reversed-phase high performance liquid chromatography (RP-HPLC), the retention of

  18. Gas chromatography-mass spectrometry and high-performance liquid chromatographic analyses of thermal degradation products of common plastics

    OpenAIRE

    Pacakova, V.; Leclercq, P.A.

    1991-01-01

    The thermo-oxidation of five commonly used materials, namely low-density polyethylene, retarded polyethylene, paper with a polyethylene foil, a milk package and filled polypropylene, was studied. Capillary gas chromatography and gas chromatography-mass spectrometry were used to analyze the volatile degradation products, while high-performance liquid chromatography was employed to measure polycyclic aromatic hydrocarbons. The results are discussed from the point of view of toxicity of the prod...

  19. Determination of dasatinib in the tablet dosage form by ultra high performance liquid chromatography, capillary zone electrophoresis, and sequential injection analysis.

    Science.gov (United States)

    Gonzalez, Aroa Garcia; Taraba, Lukáš; Hraníček, Jakub; Kozlík, Petr; Coufal, Pavel

    2017-01-01

    Dasatinib is a novel oral prescription drug proposed for treating adult patients with chronic myeloid leukemia. Three analytical methods, namely ultra high performance liquid chromatography, capillary zone electrophoresis, and sequential injection analysis, were developed, validated, and compared for determination of the drug in the tablet dosage form. The total analysis time of optimized ultra high performance liquid chromatography and capillary zone electrophoresis methods was 2.0 and 2.2 min, respectively. Direct ultraviolet detection with detection wavelength of 322 nm was employed in both cases. The optimized sequential injection analysis method was based on spectrophotometric detection of dasatinib after a simple colorimetric reaction with folin ciocalteau reagent forming a blue-colored complex with an absorbance maximum at 745 nm. The total analysis time was 2.5 min. The ultra high performance liquid chromatography method provided the lowest detection and quantitation limits and the most precise and accurate results. All three newly developed methods were demonstrated to be specific, linear, sensitive, precise, and accurate, providing results satisfactorily meeting the requirements of the pharmaceutical industry, and can be employed for the routine determination of the active pharmaceutical ingredient in the tablet dosage form. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Determination of Sunset Yellow and Tartrazine in Food Samples by Combining Ionic Liquid-Based Aqueous Two-Phase System with High Performance Liquid Chromatography

    Science.gov (United States)

    Sha, Ou; Zhu, Xiashi; Feng, Yanli; Ma, Weixing

    2014-01-01

    We proposed a simple and effective method, by coupling ionic liquid-based aqueous two-phase systems (IL-ATPSs) with high performance liquid chromatography (HPLC), for the analysis of determining tartrazine and sunset yellow in food samples. Under the optimized conditions, IL-ATPSs generated an extraction efficiency of 99% for both analytes, which could then be directly analyzed by HPLC without further treatment. Calibration plots were linear in the range of 0.01–50.0 μg/mL for both Ta and SY. The limits of detection were 5.2 ng/mL for Ta and 6.9 ng/mL for SY. This method proves successful for the separation/analysis of tartrazine and sunset yellow in soft drink sample, candy sample, and instant powder drink and leads to consistent results as obtained from the Chinese national standard method. PMID:25538857

  1. Determination of Sunset Yellow and Tartrazine in Food Samples by Combining Ionic Liquid-Based Aqueous Two-Phase System with High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Ou Sha

    2014-01-01

    Full Text Available We proposed a simple and effective method, by coupling ionic liquid-based aqueous two-phase systems (IL-ATPSs with high performance liquid chromatography (HPLC, for the analysis of determining tartrazine and sunset yellow in food samples. Under the optimized conditions, IL-ATPSs generated an extraction efficiency of 99% for both analytes, which could then be directly analyzed by HPLC without further treatment. Calibration plots were linear in the range of 0.01–50.0 μg/mL for both Ta and SY. The limits of detection were 5.2 ng/mL for Ta and 6.9 ng/mL for SY. This method proves successful for the separation/analysis of tartrazine and sunset yellow in soft drink sample, candy sample, and instant powder drink and leads to consistent results as obtained from the Chinese national standard method.

  2. Separation of three anthraquinone glycosides including two isomers by preparative high-performance liquid chromatography and high-speed countercurrent chromatography from Rheum tanguticum Maxim. ex Balf.

    Science.gov (United States)

    Chen, Tao; Li, Hongmei; Zou, Denglang; Liu, Yongling; Chen, Chen; Zhou, Guoying; Li, Yulin

    2016-08-01

    Anthraquinone glycosides, such as chrysophanol 1-O-β-d-glucoside, chrysophanol 8-O-β-d-glucoside, and physion 8-O-β-d-glucoside, are the accepted important active components of Rheum tanguticum Maxim. ex Balf. due to their pharmacological properties: antifungal, antimicrobial, cytotoxic, and antioxidant activities. However, an effective method for the separation of the above-mentioned anthraquinone glycosides from this herb is not currently available. Especially, greater difficulty existed in the separation of the two isomers chrysophanol 1-O-β-d-glucoside and chrysophanol 8-O-β-d-glucoside. This study demonstrated an efficient strategy based on preparative high-performance liquid chromatography and high-speed countercurrent chromatography for the separation of the above-mentioned anthraquinone glycosides from Rheum tanguticum Maxim.ex Balf. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Determination of oxymatrine in Sophora Radix by high performance liquid chromatography

    International Nuclear Information System (INIS)

    Yang, Seung Kwon; Yun, Young Ja; Namgung, Mi Ok

    2004-01-01

    A high performance liquid chromatographic method was designed for the quantitative analysis of oxymatrine in Sophora Radix. The separation of oxymatrine was performed by reversed-phase chromatography with a C 18 column and a buffered aqueous solution containing acetonitrile, and monitored by UV absorption at 215 nm. Extraction of oxymatrine in Sophora Radix was carried out using various solvents and extraction methods. The optimum extraction efficiency for the crushed Sophora Radix was achieved by reflux at 80 .deg. C in 50% ethanol for five hours. Most extraction methods used to complicate pretreatments. In this study, sublimation was employed for a extraction method without going through complicate pretreatments. Sublimation was carried out under high vacuum (1x10 -3 torr) and at high temperature (200 .deg. C). Extraction efficiency using Sublimation was found to be inferior to other extraction methods

  4. Application of dispersive liquid-liquid microextraction for the preconcentration of eight parabens in real samples and their determination by high-performance liquid chromatography.

    Science.gov (United States)

    Shen, Xiong; Liang, Jian; Zheng, Luxia; Lv, Qianzhou; Wang, Hong

    2017-11-01

    A simple and sensitive method for the simultaneous determination of eight parabens in human plasma and urine samples was developed. The samples were preconcentrated using dispersive liquid-liquid microextraction based on the solidification of floating organic drops and determined by high-performance liquid chromatography with ultraviolet detection. The influence of variables affecting the extraction efficiency was investigated and optimized using Placket-Burman design and Box-Behnken design. The optimized values were: 58 μL of 1-decanol (as extraction solvent), 0.65 mL methanol (as disperser solvent), 1.5% w/v NaCl in 5.0 mL of sample solution, pH 10.6, and 4.0 min centrifugation at 4000 rpm. The extract was injected into the high-performance liquid chromatography system for analysis. Under the optimum conditions, the linear ranges for eight parabens in plasma and urine were 1.0-1000 ng/mL, with correlation coefficients above 0.994. The limit of detection was 0.2-0.4 and 0.1-0.4 ng/mL for plasma and urine samples, respectively. Relative recoveries were between 80.3 and 110.7%, while relative standard deviations were less than 5.4%. Finally, the method was applied to analyze the parabens in 98 patients of primary breast cancer. Results showed that parabens existed widely, at least one paraben detected in 96.9% (95/98) of plasma samples and 98.0% (96/98) of urine samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Determination of low molecular weight thiols using monobromobimane fluorescent labeling and high-performance liquid chromatography

    Science.gov (United States)

    Fahey, Robert C.; Newton, Gerald L.

    1988-01-01

    Methods are described for the preparation and high-performance liquid chromatography (HPLC) analysis of monobromobimane derivatives of low molecular weight thiols in extracts of biological samples. Typical problems encountered in the development and application of these methods are discussed. Analysis of mung bean extract is used as an example.

  6. Analysis of major antioxidants from extracts of Myrmecodia pendans by UV/visible spectrophotometer, liquid chromatography/tandem mass spectrometry, and high-performance liquid chromatography/UV techniques.

    Science.gov (United States)

    Engida, Adam Mekonnen; Faika, Sitti; Nguyen-Thi, Bich Thuyen; Ju, Yi-Hsu

    2015-06-01

    In the present work, heat reflux extraction with ethanol/water (80:20; v/v) as the solvent was used to extract antioxidants from Myrmecodia pendans. The crude extract (CE) was fractionated using hexane and ethyl acetate. Ethyl acetate fraction (EAF) and aqueous fraction were collected. Antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl-radical radical and ferric reducing power of the CE, EAF, and aqueous fraction were evaluated. EAF showed comparable antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl-radical radical and ferric reducing power to those of the CE. UV/visible, liquid chromatography/electrospray ionization/tandem mass spectrometry, and high-performance liquid chromatography were employed for identifying the major antioxidant compounds in the EAF. Three major phenolic compounds (rosmarinic acid, procyanidin B1, and polymer of procyanidin B1) were identified. The first two compounds were confirmed and quantified by high-performance liquid chromatography using authentic standards, but confirmation of the third compound was hampered by a lack of commercial standard. Concentrations of rosmarinic acid and procyanidin B1 in the EAF were found to be 20.688 ± 1.573 mg/g dry sample and 3.236 ± 0.280 mg/g dry sample, respectively. All these three compounds are reported for the first time in sarang semut. Copyright © 2014. Published by Elsevier B.V.

  7. Analysis of major antioxidants from extracts of Myrmecodia pendans by UV/visible spectrophotometer, liquid chromatography/tandem mass spectrometry, and high-performance liquid chromatography/UV techniques

    Directory of Open Access Journals (Sweden)

    Adam Mekonnen Engida

    2015-06-01

    Full Text Available In the present work, heat reflux extraction with ethanol/water (80:20; v/v as the solvent was used to extract antioxidants from Myrmecodia pendans. The crude extract (CE was fractionated using hexane and ethyl acetate. Ethyl acetate fraction (EAF and aqueous fraction were collected. Antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl-radical radical and ferric reducing power of the CE, EAF, and aqueous fraction were evaluated. EAF showed comparable antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl-radical radical and ferric reducing power to those of the CE. UV/visible, liquid chromatography/electrospray ionization/tandem mass spectrometry, and high-performance liquid chromatography were employed for identifying the major antioxidant compounds in the EAF. Three major phenolic compounds (rosmarinic acid, procyanidin B1, and polymer of procyanidin B1 were identified. The first two compounds were confirmed and quantified by high-performance liquid chromatography using authentic standards, but confirmation of the third compound was hampered by a lack of commercial standard. Concentrations of rosmarinic acid and procyanidin B1 in the EAF were found to be 20.688 ± 1.573 mg/g dry sample and 3.236 ± 0.280 mg/g dry sample, respectively. All these three compounds are reported for the first time in sarang semut.

  8. Simultaneous determination of estrogens and progestogens in honey using high performance liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    This work describes the development and validation of a method for the simultaneous determination of 13 estrogens and progestogens in honey by high performance liquid chromatography-tandem mass spectrometry. The target compounds were preconcentrated by solid phase extraction. Pretreatment variables ...

  9. Determination of methyldibromoglutaronitrile in cosmetic products by high-performance liquid chromatography with electrochemical detection. Method validation

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Zachariae, Claus; Johansen, Jeanne D

    2004-01-01

    An increased frequency of contact allergy to methyldibromoglutaronitrile (MDBGN), a commonly used preservative in cosmetics and other consumer products, has been reported in recent years. A high-performance liquid chromatography (HPLC) method for the determination of MDBGN in cosmetic products has...

  10. Determination of methyldibromoglutaronitrile in cosmetic products by high-performance liquid chromatography with electrochemical detection. Method validation

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Zachariae, Claus; Johansen, Jeanne D

    2004-01-01

    An increased frequency of contact allergy to methyldibromoglutaronitrile (MDBGN), a commonly used preservative in cosmetics and other consumer products, has been reported in recent years. A high-performance liquid chromatography (HPLC) method for the determination of MDBGN in cosmetic products ha...

  11. Determination of sulfonamides in butter samples by ionic liquid magnetic bar liquid-phase microextraction high-performance liquid chromatography.

    Science.gov (United States)

    Wu, Lijie; Song, Ying; Hu, Mingzhu; Xu, Xu; Zhang, Hanqi; Yu, Aimin; Ma, Qiang; Wang, Ziming

    2015-01-01

    A novel, simple, and environmentally friendly pretreatment method, ionic liquid magnetic bar liquid-phase microextraction, was developed for the determination of sulfonamides in butter samples by high-performance liquid chromatography. The ionic liquid magnetic bar was prepared by inserting a stainless steel wire into the hollow of a hollow fiber and immobilizing ionic liquid in the micropores of the hollow fiber. In the extraction process, the ionic liquid magnetic bars were used to stir the mixture of sample and extraction solvent and enrich the sulfonamides in the mixture. After extraction, the analyte-adsorbed ionic liquid magnetic bars were readily isolated with a magnet from the extraction system. It is notable that the present method was environmentally friendly since water and only several microliters of ionic liquid were used in the whole extraction process. Several parameters affecting the extraction efficiency were investigated and optimized, including the type of ionic liquid, sample-to-extraction solvent ratio, the number of ionic liquid magnetic bars, extraction temperature, extraction time, salt concentration, stirring speed, pH of the extraction solvent, and desorption conditions. The recoveries were in the range of 73.25-103.85 % and the relative standard deviations were lower than 6.84 %. The experiment results indicated that the present method was effective for the extraction of sulfonamides in high-fat content samples.

  12. On the use of ionic liquids as mobile phase additives in high-performance liquid chromatography. A review.

    Science.gov (United States)

    García-Alvarez-Coque, M C; Ruiz-Angel, M J; Berthod, A; Carda-Broch, S

    2015-07-09

    The popularity of ionic liquids (ILs) has grown during the last decades in several analytical separation techniques. Consequently, the number of reports devoted to the applications of ILs is still increasing. This review is focused on the use of ILs (mainly imidazolium-based associated to chloride and tetrafluoroborate) as mobile phase additives in high-performance liquid chromatography (HPLC). In this approach, ILs just function as salts, but keep several kinds of intermolecular interactions, which are useful for chromatographic separations. Both cation and anion can be adsorbed on the stationary phase, creating a bilayer. This gives rise to hydrophobic, electrostatic and other specific interactions with the stationary phase and solutes, which modify the retention behaviour and peak shape. This review updates the advances in this field, with emphasis on topics not always deeply considered in the literature, such as the mechanisms of retention, the estimation of the suppressing potency of silanols, modelling and optimisation of the chromatographic performance, and the comparison with other additives traditionally used to avoid the silanol problem. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Comparison of ultra-high performance supercritical fluid chromatography and ultra-high performance liquid chromatography for the separation of spirostanol saponins.

    Science.gov (United States)

    Zhu, Ling-Ling; Zhao, Yang; Xu, Yong-Wei; Sun, Qing-Long; Sun, Xin-Guang; Kang, Li-Ping; Yan, Ren-Yi; Zhang, Jie; Liu, Chao; Ma, Bai-Ping

    2016-02-20

    Spirostanol saponins are important active components of some herb medicines, and their isolation and purification are crucial for the research and development of traditional Chinese medicines. We aimed to compare the separation of spirostanol saponins by ultra-high performance supercritical fluid chromatography (UHPSFC) and ultra-high performance liquid chromatography (UHPLC). Four groups of spirostanol saponins were separated respectively by UHPSFC and UHPLC. After optimization, UHPSFC was performed with a HSS C18 SB column or a Diol column and with methanol as the co-solvent. A BEH C18 column and mobile phase containing water (with 0.1% formic acid) and acetonitrile were used in UHPLC. We found that UHPSFC could be performed automatically and quickly. It is effective in separating the spirostanol saponins which share the same aglycone and vary in sugar chains, and is very sensitive to the number and the position of hydroxyl groups in aglycones. However, the resolution of spirostanol saponins with different aglycones and the same sugar moiety by UHPSFC was not ideal and could be resolved by UHPLC instead. UHPLC is good at differentiating the variation in aglycones, and is influenced by double bonds in aglycones. Therefore, UHPLC and UHPSFC are complementary in separating spirostanol saponins. Considering the naturally produced spirostanol saponins in herb medicines are different both in aglycones and in sugar chains, a better separation can be achieved by combination of UHPLC and UHPSFC. UHPSFC is a powerful technique for improving the resolution when UHPLC cannot resolve a mixture of spirostanol saponins and vice versa. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. A high-performance liquid chromatography-based radiometric assay for acyl-CoA:alcohol transacylase from jojoba.

    Science.gov (United States)

    Garver, W S; Kemp, J D; Kuehn, G D

    1992-12-01

    Acyl-CoA:alcohol transacylase catalyzes the final step in the biosynthesis of storage liquid wax esters from acyl-CoA fatty acids and fatty alcohols in a limited number of microbes, algae, and Simmondsia chinensis Link (jojoba). An improved and automated method of enzyme assay for this catalyst from cotyledons of jojoba is described. The assay method uses reversed-phase C18 high performance liquid chromatography (HPLC) to separate the labeled C30:1 liquid wax product, [14C]-dodecanyl-octadecenoate, from the unreacted substrate, [14C]octadecenoyl-CoA (oleyl-CoA), and other components produced from enzymes present in the crude homogenate of jojoba cotyledons, including [14C]-octadecenoic acid (oleic acid) and [14C]octadecenol (oleyol). Methods are also described for microscale chemical synthesis in one vessel of 14C-radiolabeled substrates and products for the transacylase. These labeled reagents are required to confirm the HPLC separations of reaction products. The radioactive components are quantitated using an on-line flow-through scintillation detector enabling sensitive and precise analysis of the reaction products.

  15. Identification and Quantitation of Asparagine and Citrulline Using High-Performance Liquid Chromatography (HPLC)

    OpenAIRE

    Bai, Cheng; Reilly, Charles C.; Wood, Bruce W.

    2007-01-01

    High-performance liquid chromatography (HPLC) analysis was used for identification of two problematic ureides, asparagine and citrulline. We report here a technique that takes advantage of the predictable delay in retention time of the co-asparagine/citrulline peak to enable both qualitative and quantitative analysis of asparagine and citrulline using the Platinum EPS reverse-phase C18 column (Alltech Associates). Asparagine alone is eluted earlier than citrulline alone, but when both of them...

  16. Overview of online two-dimensional liquid chromatography based on cell membrane chromatography for screening target components from traditional Chinese medicines.

    Science.gov (United States)

    Muhammad, Saqib; Han, Shengli; Xie, Xiaoyu; Wang, Sicen; Aziz, Muhammad Majid

    2017-01-01

    Cell membrane chromatography is a simple, specific, and time-saving technique for studying drug-receptor interactions, screening of active components from complex mixtures, and quality control of traditional Chinese medicines. However, the short column life, low sensitivity, low column efficiency (so cannot resolve satisfactorily mixture of compounds), low peak capacity, and inefficient in structure identification were bottleneck in its application. Combinations of cell membrane chromatography with multidimensional chromatography such as two-dimensional liquid chromatography and high sensitivity detectors like mass have significantly reduced many of the above-mentioned shortcomings. This paper provides an overview of the current advances in online two-dimensional-based cell membrane chromatography for screening target components from traditional Chinese medicines with particular emphasis on the instrumentation, preparation of cell membrane stationary phase, advantages, and disadvantages compared to alternative approaches. The last section of the review summarizes the applications of the online two-dimensional high-performance liquid chromatography based cell membrane chromatography reported since its emergence to date (2010-June 2016). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Core-Shell Columns in High-Performance Liquid Chromatography: Food Analysis Applications

    Science.gov (United States)

    Preti, Raffaella

    2016-01-01

    The increased separation efficiency provided by the new technology of column packed with core-shell particles in high-performance liquid chromatography (HPLC) has resulted in their widespread diffusion in several analytical fields: from pharmaceutical, biological, environmental, and toxicological. The present paper presents their most recent applications in food analysis. Their use has proved to be particularly advantageous for the determination of compounds at trace levels or when a large amount of samples must be analyzed fast using reliable and solvent-saving apparatus. The literature hereby described shows how the outstanding performances provided by core-shell particles column on a traditional HPLC instruments are comparable to those obtained with a costly UHPLC instrumentation, making this novel column a promising key tool in food analysis. PMID:27143972

  18. Hb A1c Separation by High Performance Liquid Chromatography in Hemoglobinopathies

    OpenAIRE

    Chandrashekar, Vani

    2016-01-01

    Hb A1c measurement is subject to interference by hemoglobin traits and this is dependent on the method used for determination. In this paper we studied the difference between Hb A1c measured by HPLC in hemoglobin traits and normal chromatograms. We also studied the correlation of Hb A1c with age. Hemoglobin analysis was carried out by high performance liquid chromatography. Spearman's rank correlation was used to study correlation between A1c levels and age. Mann-Whitney U test was used to st...

  19. Determination of 1-hydroxypyrene in human urine by high-performance liquid chromatography

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Poulsen, O M; Christensen, J M

    1993-01-01

    A high-performance liquid chromatography (HPLC)/fluorescence method for quantitative analysis of 1-hydroxypyrene in urine was developed. The method validation analysis showed the method to be in analytical control. No significant systematical errors could be demonstrated. The entire run time....... The developed method is presently used for measurement of 1-hydroxypyrene in urine samples from workers exposed to a low airborne level of polycyclic aromatic hydrocarbons, generally less than 25 micrograms/m3. The urine samples of exposed workers (n = 122) showed a range of 1-hydroxypyrene from the limit...

  20. Synthesis of monodisperse silica microspheres and modification with diazoresin for mixed-mode ultra high performance liquid chromatography separations.

    Science.gov (United States)

    Cong, Hailin; Yu, Bing; Tian, Chao; Zhang, Shuai; Yuan, Hua

    2017-11-01

    Monodisperse silica particles with average diameters of 1.9-2.9 μm were synthesized by a modified Stöber method, in which tetraethyl orthosilicate was continuously supplied to the reaction mixture containing KCl electrolyte, water, ethanol, and ammonia. The obtained silica particles were modified by self-assembly with positively charged photosensitive diazoresin on the surface. After treatment with ultraviolet light, the ionic bonding between silica and diazoresin was converted into covalent bonding through a unique photochemistry reaction of diazoresin. Depending on the chemical structure of diazoresin and mobile phase composition, the diazoresin-modified silica stationary phase showed different separation mechanisms, including reversed phase and hydrophilic interactions. Therefore, a variety of baseline separation of benzene analogues and organic acids was achieved by using the diazoresin-modified silica particles as packing materials in ultra high performance liquid chromatography. According to the π-π interactional difference between carbon rings of fullerenes and benzene rings of diazoresin, C 60 and C 70 were also well separated by ultra-high performance liquid chromatography. Because it has a small size, the ∼2.5 μm monodisperse diazoresin-modified silica stationary phase shows ultra-high efficiency compared with the commercial C 18 -silica high-performance liquid chromatography stationary phase with average diameters of ∼5 μm. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Evaluation between ultrahigh pressure liquid chromatography and high-performance liquid chromatography analytical methods for characterizing natural dyestuffs.

    Science.gov (United States)

    Serrano, Ana; van Bommel, Maarten; Hallett, Jessica

    2013-11-29

    An evaluation was undertaken of ultrahigh pressure liquid chromatography (UHPLC) in comparison to high-performance liquid chromatography (HPLC) for characterizing natural dyes in cultural heritage objects. A new UHPLC method was optimized by testing several analytical parameters adapted from prior UHPLC studies developed in diverse fields of research. Different gradient elution programs were tested on seven UHPLC columns with different dimensions and stationary phase compositions by applying several mobile phases, flow rates, temperatures, and runtimes. The UHPLC method successfully provided more improved data than that achieved by the HPLC method. Indeed, even though carminic acid has shown circa 146% higher resolution with HPLC, UHPLC resulted in an increase of 41-61% resolution and a decrease of 91-422% limit of detection, depending on the dye compound. The optimized method was subsequently assigned to analyse 59 natural reference materials, in which 85 different components were ascribed with different physicochemical properties, in order to create a spectral database for future characterization of dyes in cultural heritage objects. The majority of these reference samples could be successfully distinguished with one single method through the examination of these compounds' retention times and their spectra acquired with a photodiode array detector. These results demonstrate that UHPLC analyses are extremely valuable for the acquisition of more precise chromatographic information concerning natural dyes with complex mixtures of different and/or closely related physicochemical properties, essential for distinguishing similar species of plants and animals used to colour cultural heritage objects. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Purification of a 166mHo solution by successive high-performance liquid chromatography and gravitational chromatography for half-life determination

    International Nuclear Information System (INIS)

    Florence Gueguen; Helene Isnard; Carole Bresson; Celine Caussignac; Guillaume Stadelmann; Anthony Nonell; Sebastien Mialle; Karsten Kossert; Frederic Chartier

    2014-01-01

    A methodology to purify a 166m Ho solution has been developed by a combination of activity and mass concentration measurements in order to further determine the 166m Ho half-life. The isobaric interference at m/q ≃ 166 requires Ho purification from non-natural Er with a high purification degree due to the large amount of Ho as opposed to Er. The Ho/Er separation was achieved using high-performance liquid chromatography on a semi-preparative column followed by purification on gravitational chromatography. The efficiency of the separation was evaluated after precise determination of the Er isotopic composition. The purification methodology enabled to separate Ho from Er. (author)

  3. Constructing a LabVIEW-Controlled High-Performance Liquid Chromatography (HPLC) System: An Undergraduate Instrumental Methods Exercise

    Science.gov (United States)

    Smith, Eugene T.; Hill, Marc

    2011-01-01

    In this laboratory exercise, students develop a LabVIEW-controlled high-performance liquid chromatography system utilizing a data acquisition device, two pumps, a detector, and fraction collector. The programming experience involves a variety of methods for interface communication, including serial control, analog-to-digital conversion, and…

  4. Quantitation of bilirubin conjugates with high-performance liquid chromatography in patients with low total serum bilirubin levels

    NARCIS (Netherlands)

    Jansen, P. L.; Cuypers, H. T.; Peters, W. H.

    1984-01-01

    Bilirubin mono- and diconjugates were determined by alkaline methanolysis and high-performance liquid chromatography (HPLC) in serum from patients with metastatic liver disease and liver cirrhosis. Conjugates could be detected and quantitated at normal or low total bilirubin levels. Comparison with

  5. Identification and quantification of cannabinoids in Cannabis sativa L. plants by high performance liquid chromatography-mass spectrometry

    NARCIS (Netherlands)

    Aizpurua-Olaizola, Oier; Omar, Jone; Navarro, Patricia; Olivares, Maitane; Etxebarria, Nestor; Usobiaga, Aresatz

    2014-01-01

    High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) has been successfully applied to cannabis plant extracts in order to identify cannabinoid compounds after their quantitative isolation by means of supercritical fluid extraction (SFE). MS conditions were optimized by means

  6. Toxic Compounds Analysis With High Performance Liquid Chromatography Detected By Electro Chemical Detector (Ecd)

    OpenAIRE

    Hideharu Shintaniq

    2014-01-01

    The principal area of application of high performance liquid chromatography-electrochemical detector (HPLC-ECD) has been in the analysis of naturally-occurring analytes, such as catecholamines, and pharmaceuticals in biological samples, HPLC-ECD has also applied to the analysis of pesticides and other analytes of interest to the toxicologist. In this paper, toxic area is described. In these, ammatoxins, aromatic amine, nitro-compounds, algal toxins, fungal toxins, pesticides, veterinary drug ...

  7. Determination of Peroxide-Based Explosives Using Liquid Chromatography with On-Line Infrared Detection

    NARCIS (Netherlands)

    Schulte-Ladbeck, Rasmus; Edelmann, Andrea; Quintas, Guillermo; Lendl, Bernhard; Karst, U.

    2006-01-01

    A nondestructive analytical method for peroxide-based explosives determination in solid samples is described. Reversed-phase high-performance liquid chromatography in combination with on-line Fourier transform infrared (FT-IR) detection is used for the analysis of triacetonetriperoxide (TATP) and

  8. Instrumental liquid chromatography: a practical manual on high-performance liquid chromatographic methods

    National Research Council Canada - National Science Library

    Parris, N. A

    1976-01-01

    Available texts on liquid chromatography have tended to emphasize the developments in the theoretical understanding of the technique and methodology or to list numerous applications, complete with experimental details...

  9. NONLINEAR-REGRESSION METHODS FOR MODELING OF HETEROSCEDASTIC RETENTION DATA IN REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

    NARCIS (Netherlands)

    HENDRIKS, MMWB; COENEGRACHT, PMJ; DOORNBOS, DA

    1994-01-01

    New models have been developed that accurately describe the response surfaces of capacity factors that are a function of changes in the pH and the fraction of organic modifier in reversed-phase high-performance liquid chromatography (RP-HPLC). The purpose of this article is to illustrate one of the

  10. Neutral monosaccharide composition analysis of plant-derived oligo- and polysaccharides by high performance liquid chromatography.

    Science.gov (United States)

    Yan, Jun; Shi, Songshan; Wang, Hongwei; Liu, Ruimin; Li, Ning; Chen, Yonglin; Wang, Shunchun

    2016-01-20

    A novel analytical method for neutral monosaccharide composition analysis of plant-derived oligo- and polysaccharides was developed using hydrophilic interaction liquid chromatography coupled to a charged aerosol detector. The effects of column type, additives, pH and column temperature on retention and separation were evaluated. Additionally, the method could distinguish potential impurities in samples, including chloride, sulfate and sodium, from sugars. The results of validation demonstrated that this method had good linearity (R(2) ≥ 0.9981), high precision (relative standard deviation ≤ 4.43%), and adequate accuracy (94.02-103.37% recovery) and sensitivity (detection limit: 15-40 ng). Finally, the monosaccharide compositions of the polysaccharide from Eclipta prostrasta L. and stachyose were successfully profiled through this method. This report represents the first time that all of these common monosaccharides could be well-separated and determined simultaneously by high performance liquid chromatography without additional derivatization. This newly developed method is convenient, efficient and reliable for monosaccharide analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. New high-performance liquid chromatography assay for glycosyltransferases based on derivatization with anthranilic acid and fluorescence detection.

    Science.gov (United States)

    Anumula, Kalyan Rao

    2012-07-01

    Assays were developed using the unique labeling chemistry of 2-aminobenzoic acid (2AA; anthranilic acid, AA) for measuring activities of both β1-4 galactosyltransferase (GalT-1) and α2-6 sialyltransferase (ST-6) by high-performance liquid chromatography (HPLC) with fluorescence detection (Anumula KR. 2006. Advances in fluorescence derivatization methods for high-performance liquid chromatographic analysis of glycoprotein carbohydrates. Anal Biochem. 350:1-23). N-Acetylglucosamine (GlcNAc) and N-acetyllactosamine were used as acceptors and uridine diphosphate (UDP)-galactose and cytidine monophosphate (CMP)-N-acetylneuraminic acid (NANA) as donors for GalT-1 and ST-6, respectively. Enzymatic products were labeled in situ with AA and were separated from the substrates on TSKgel Amide 80 column using normal-phase conditions. Enzyme units were determined from the peak areas by comparison with the concomitantly derivatized standards Gal-β1-4GlcNAc and NANA-α2-6 Gal-β1-4GlcNAc. Linearity (time and enzyme concentration), precision (intra- and interassay) and reproducibility for the assays were established. The assays were found to be useful in monitoring the enzyme activities during isolation and purification. The assays were highly sensitive and performed equal to or better than the traditional radioactive sugar-based measurements. The assay format can also be used for measuring the activity of other transferases, provided that the carbohydrate acceptors contain a reducing end for labeling. An assay for glycoprotein acceptors was developed using IgG. A short HPLC profiling method was developed for the separation of IgG glycans (biantennary G0, G1, G2, mono- and disialylated), which facilitated the determination of GalT-1 and ST-6 activities in a rapid manner. Furthermore, this profiling method should prove useful for monitoring the changes in IgG glycans in clinical settings.

  12. Collaborative trial validation study of two methods, one based on high performance liquid chromatography-tandem mass spectrometry and on gas chromatography-mass spectrometry for the determination of acrylamide in bakery and potato products.

    Science.gov (United States)

    Wenzl, Thomas; Karasek, Lubomir; Rosen, Johan; Hellenaes, Karl-Erik; Crews, Colin; Castle, Laurence; Anklam, Elke

    2006-11-03

    A European inter-laboratory study was conducted to validate two analytical procedures for the determination of acrylamide in bakery ware (crispbreads, biscuits) and potato products (chips), within a concentration range from about 20 microg/kg to about 9000 microgg/kg. The methods are based on gas chromatography-mass spectrometry (GC-MS) of the derivatised analyte and on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) of native acrylamide. Isotope dilution with isotopically labelled acrylamide was an integral part of both methods. The study was evaluated according to internationally accepted guidelines. The performance of the HPLC-MS/MS method was found to be superior to that of the GC-MS method and to be fit-for-the-purpose.

  13. Direct enantioseparation of nitrogen-heterocyclic pesticides on cellulose-based chiral column by high-performance liquid chromatography.

    Science.gov (United States)

    Chai, Tingting; Yang, Wenwen; Qiu, Jing; Hou, Shicong

    2015-01-01

    The enantiomeric separation of eight pesticides including bitertanol (), diclobutrazol (), fenbuconazole (), triticonazole (), imazalil (), triapenthenol (), ancymidol (), and carfentrazone-ethyl () was achieved, using normal-phase high-performance liquid chromatography on two cellulosed-based chiral columns. The effects of isopropanol composition from 2% to 30% in the mobile phase and column temperature from 5 to 40 °C were investigated. Satisfactory resolutions were obtained for bitertanol (), triticonazole (), imazalil () with the (+)-enantiomer eluted first and fenbuconazole () with the (-)-enantiomer eluted first on Lux Cellulose-2 and Lux Cellulose-3. (+)-Enantiomers of diclobutrazol () and triapenthenol () were first eluted on Lux Cellulose-2. (-)-Carfentrazone-ethyl () were eluted first on Lux Cellulose-2 and Lux Cellulose-3 with incomplete separation. Reversed elution orders were obtained for ancymidol (7). (+)-Ancymidol was first eluted on Lux Cellulose-2 while on Lux Cellulose-3 (-)-ancymidol was first eluted. The results of the elution order at different column temperatures suggested that column temperature did not affect the optical signals of the enantiomers. These results will be helpful to prepare and analyze individual enantiomers of chiral pesticides. © 2014 Wiley Periodicals, Inc.

  14. Separation and preparation of xanthochymol and guttiferone E by high performance liquid chromatography and high speed counter-current chromatography combined with silver nitrate coordination reaction.

    Science.gov (United States)

    Li, Jun; Gao, Ruixi; Zhao, Dan; Huang, Xianju; Chen, Yu; Gan, Fei; Liu, Hui; Yang, Guangzhong

    2017-08-18

    Xanthochymol (XCM) and guttiferone E (GFE), a pair of π bond benzophenone isomers from Garcinia xanthochymus, were once reported to be difficult or impossible to separate. The present study reports the successful separation of these two isomers through high performance liquid chromatography (HPLC), as well as their effective isolation using high speed counter-current chromatography (HSCCC) based on the silver nitrate (AgNO 3 ) coordination reaction. First, an effective HPLC separation system was developed, achieving a successful baseline separation with resolution of 2.0. Based on the partition coefficient (K) resolved by HPLC, the two-phase solvent system was determined as n-hexane, methanol and water with the uncommon volume ratio of 4:6:1. A crude extract of Garcinia xanthochymus (0.2g) was purified by normal HSCCC and refined with AgNO 3 -HSCCC. Monomers of XCM and GFE were identified by HPLC, mass spectrometry (MS) and nuclear magnetic resonance (NMR). The results demonstrate the separation and isolation of π bond benzophenone isomers using ordinary octadecyl silane (C 18 ) columns and HSCCC. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Analysis of chlorpheniramine in human urine samples using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Mehdi Maham

    2014-09-01

    Full Text Available A simple and environmentally friendly microextraction technique was used for determination of chlorpheniramine (CPM, an antihistamine drug, in human urine samples using dispersive liquid-liquid microextraction (DLLME followed by high performance liquid chromatography with diode array detection (HPLC-DAD. In this extraction technique, an appropriate mixture of acetonitrile (disperser solvent and carbon tetrachloride (extraction solvent was rapidly injected into the urine sample containing the target analyte. Tiny droplets of extractant were formed and dispersed into the sample solution and then sedimented at the bottom of the conical test tube by centrifugation. Under optimal conditions, the calibration curve was linear in the range of 0.055-5.5 µg mL-1, with a detection limit of 16.5 ng mL-1. This proposed method was successfully applied to the analysis of real urine samples. Low consumption of toxic organic solvents, simplicity of operation, low cost and acceptable figures of merit are the main advantages of the proposed technique.

  16. Determination of chlorophenols in honey samples using in-situ ionic liquid-dispersive liquid-liquid microextraction as a pretreatment method followed by high-performance liquid chromatography.

    Science.gov (United States)

    Fan, Chen; Li, Nai; Cao, Xueli

    2015-05-01

    In-situ ionic liquid-dispersive liquid-liquid microextraction (IL-DLLME) method was developed as a pretreatment method for the detection of six chlorophenols (CPs) in honey samples. The hydrophobic ionic liquid [C4MIM][NTf2], formed in-situ by the hydrophilic ionic liquid [C4MIM][BF4] and the ion exchange reagent LiNTf2 was used as the microextractant solvent of CPs from honey sample. Then the enriched analytes were back-extracted into 40 μL of 0.14 M NaOH solution and finally subjected to analysis by high-performance liquid chromatography. The method showed low limit of detection of CPs, 0.8-3.2 μg/L and high enrichment factor, 34-65 with the recoveries range from 91.60% to 114.33%. The method is simple, rapid, environmentally friendly and with high extraction efficiency. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Optimisation of high-performance liquid chromatography with diode array detection using an automatic peak tracking procedure based on augmented iterative target transformation factor analysis

    NARCIS (Netherlands)

    van Zomeren, Paul; Hoogvorst, A.; Coenegracht, P.M J; de Jong, G.J.

    2004-01-01

    An automated method for the optimisation of high-performance liquid chromatography is developed. First of all, the sample of interest is analysed with various eluent compositions. All obtained data are combined into one augmented data matrix. Subsequently, augmented iterative target transformation

  18. EXTRACTION AND QUANTITATIVE ANALYSIS OF ELEMENTAL SULFUR FROM SULFIDE MINERAL SURFACES BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY. (R826189)

    Science.gov (United States)

    A simple method for the quantitative determination of elemental sulfur on oxidized sulfide minerals is described. Extraction of elemental sulfur in perchloroethylene and subsequent analysis with high-performance liquid chromatography were used to ascertain the total elemental ...

  19. Optimized method for the determination of itopride in human plasma by high-performance liquid chromatography with fluorimetric detection.

    Science.gov (United States)

    Ptácek, Pavel; Klíma, Josef; Macek, Jan

    2009-03-15

    A high-performance liquid chromatographic method with fluorescence detection for the determination of itopride in human plasma is reported. The sample preparation was based on liquid-liquid extraction of itopride from plasma with t-butylmethylether and dichloromethane (70:30, v/v) mixture followed by a back extraction of the analyte to the phosphate buffer (pH 3.2). Liquid chromatography was performed on an octadecylsilica column (55 mm x 4 mm, 3 microm particles), the mobile phase consisted of acetonitrile-triethylamine-15 mM dihydrogenpotassium phosphate (14.5:0.5:85, v/v/v), pH of the mobile phase was adjusted to 4.8. The run time was 3 min. The fluorimetric detector was operated at 250/342 nm (excitation/emission wavelength). Naratriptan was used as the internal standard. The limit of quantitation was 9.5 ng/ml using 0.5 ml of plasma. The method precision and inaccuracy were less than 8%. The assay was applied to the analysis of samples from a bioequivalence study.

  20. High-throughput, Highly Sensitive Analyses of Bacterial Morphogenesis Using Ultra Performance Liquid Chromatography*

    Science.gov (United States)

    Desmarais, Samantha M.; Tropini, Carolina; Miguel, Amanda; Cava, Felipe; Monds, Russell D.; de Pedro, Miguel A.; Huang, Kerwyn Casey

    2015-01-01

    The bacterial cell wall is a network of glycan strands cross-linked by short peptides (peptidoglycan); it is responsible for the mechanical integrity of the cell and shape determination. Liquid chromatography can be used to measure the abundance of the muropeptide subunits composing the cell wall. Characteristics such as the degree of cross-linking and average glycan strand length are known to vary across species. However, a systematic comparison among strains of a given species has yet to be undertaken, making it difficult to assess the origins of variability in peptidoglycan composition. We present a protocol for muropeptide analysis using ultra performance liquid chromatography (UPLC) and demonstrate that UPLC achieves resolution comparable with that of HPLC while requiring orders of magnitude less injection volume and a fraction of the elution time. We also developed a software platform to automate the identification and quantification of chromatographic peaks, which we demonstrate has improved accuracy relative to other software. This combined experimental and computational methodology revealed that peptidoglycan composition was approximately maintained across strains from three Gram-negative species despite taxonomical and morphological differences. Peptidoglycan composition and density were maintained after we systematically altered cell size in Escherichia coli using the antibiotic A22, indicating that cell shape is largely decoupled from the biochemistry of peptidoglycan synthesis. High-throughput, sensitive UPLC combined with our automated software for chromatographic analysis will accelerate the discovery of peptidoglycan composition and the molecular mechanisms of cell wall structure determination. PMID:26468288

  1. Salting-out assisted liquid-liquid extraction coupled to ultra-high performance liquid chromatography-tandem mass spectrometry for the determination of tetracycline residues in infant foods.

    Science.gov (United States)

    Moreno-González, David; García-Campaña, Ana M

    2017-04-15

    The use of salting-out assisted liquid-liquid extraction (SALLE) combined with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) has been evaluated for the determination of tetracyclines in infant foods based on meat and vegetables or in milk. To obtain satisfactory extraction efficiencies for the studied analytes, several parameters affecting the SALLE procedure were optimized. Analytical performances of the method were satisfactory, obtaining limits of quantification lower than 0.48μgkg -1 in all cases. The precision, expressed as relative standard deviation (%, RSD) was below 11.3%. The extraction efficiency for fortified samples ranged from 89.2 to 96.8%, with RSDs lower than 7.3%. Matrix effect was evaluated for all samples studied, being lower than |21|% in all cases. In relation to the low solvent consumption, the proposed methodology could be considered rapid, cheap and environmentally friendly. Its applicability has been successfully tested in a wide range of infant foods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Determination of gouty arthritis' biomarkers in human urine using reversed-phase high-performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Lei-Wen Xiang

    2014-04-01

    Full Text Available Creatinine, uric acid, hypoxanthine and xanthine are important diagnostic biomarkers in human urine for gouty arthritis or renal disease diacrisis. A simple method for simultaneous determination of these biomarkers in urine based on reversed-phase high-performance liquid chromatography (RP-HPLC with ultraviolet (UV detector was proposed. After pretreatment by dilution, centrifugation and filtration, the biomarkers in urine samples were separated by ODS-BP column by elution with methanol/50 mM NaH2PO4 buffer solution at pH 5.26 (5:95. Good linearity between peak areas and concentrations of standards was obtained for the biomarkers with correlation coefficients in the range of 0.9957–0.9993. The proposed analytical method has satisfactory repeatability (the recovery of data in a range of creatinine, uric acid, hypoxanthine and xanthine was 93.49–97.90%, 95.38–96.45%, 112.46–115.78% and 90.82–97.13% with standard deviation of <5%, respectively and the limits of detection (LODs, S/N≥3 for creatinine, uric acid, hypoxanthine, and xanthine were 0.010, 0.025, 0.050 and 0.025 mg/L, respectively. The established method was proved to be simple, accurate, sensitive and reliable for the quantitation of gouty arthritis' biomarkers in human urine samples. The ratio of creatinine to uric acid was found to be a possible factor for assessment of gouty arthritis. Keywords: Gouty arthritis, Creatinine, Uric acid, Hypoxanthine, Xanthine, High-performance liquid chromatography

  3. Nontargeted Screening Method for Illegal Additives Based on Ultrahigh-Performance Liquid Chromatography-High-Resolution Mass Spectrometry.

    Science.gov (United States)

    Fu, Yanqing; Zhou, Zhihui; Kong, Hongwei; Lu, Xin; Zhao, Xinjie; Chen, Yihui; Chen, Jia; Wu, Zeming; Xu, Zhiliang; Zhao, Chunxia; Xu, Guowang

    2016-09-06

    Identification of illegal additives in complex matrixes is important in the food safety field. In this study a nontargeted screening strategy was developed to find illegal additives based on ultrahigh-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS). First, an analytical method for possible illegal additives in complex matrixes was established including fast sample pretreatment, accurate UHPLC separation, and HRMS detection. Second, efficient data processing and differential analysis workflow were suggested and applied to find potential risk compounds. Third, structure elucidation of risk compounds was performed by (1) searching online databases [Metlin and the Human Metabolome Database (HMDB)] and an in-house database which was established at the above-defined conditions of UHPLC-HRMS analysis and contains information on retention time, mass spectra (MS), and tandem mass spectra (MS/MS) of 475 illegal additives, (2) analyzing fragment ions, and (3) referring to fragmentation rules. Fish was taken as an example to show the usefulness of the nontargeted screening strategy, and six additives were found in suspected fish samples. Quantitative analysis was further carried out to determine the contents of these compounds. The satisfactory application of this strategy in fish samples means that it can also be used in the screening of illegal additives in other kinds of food samples.

  4. Quantification of glibenclamide in cleaning samples of pharmaceutical equipment through high performance liquid chromatography

    International Nuclear Information System (INIS)

    Baeza Fonte, Alen Nils; Diaz Aguila, Elsa Eneida; Martinez Alfonso; Nancy

    2012-01-01

    to submit a selective analytical method for quantization of glibenclamide in cleaning samples of pharmaceutical equipment using high performance liquid chromatography. The mobile phase consisted of an equal mixing of acetonitrile/phosphate buffer KH 2 PO 4 ; with 0.037 mol/L concentration pH 5.25 and flow of 1.5 mL/min, in a Nucleosil 100 C8 column. Glibenclamide was injected with progesterone as internal standard and using an UV detector= 230 nm

  5. High performance liquid chromatographic determination of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-08

    ) high performance liquid chromatography (HPLC) grade .... applications. These are important requirements if the reagent is to be applicable to on-line pre or post column derivatisation in a possible automation of the analytical.

  6. 21 CFR 862.2260 - High pressure liquid chromatography system for clinical use.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false High pressure liquid chromatography system for... Clinical Laboratory Instruments § 862.2260 High pressure liquid chromatography system for clinical use. (a) Identification. A high pressure liquid chromatography system for clinical use is a device intended to separate...

  7. Isolation and purification of six iridoid glycosides from gardenia jasminoides fruit by medium-pressure liquid chromatography combined with macroporous resin chromatography.

    Science.gov (United States)

    Wang, Yun; Liu, Hui; Shen, Lifeng; Yao, Lan; Ma, Yinlian; Yu, Dingrong; Chen, Jianhong; Li, Puling; Chen, Ying; Zhang, Cun

    2015-12-01

    Gardeniae fructus is one of the most frequently used herbs in traditional Chinese medicine. In the present study, a process for the enrichment of six iridoid glycosides from Gardeniae fructus was developed using medium-pressure liquid chromatography combined with macroporous resin and reversed-phase chromatography. The purities of different fractions from Gardeniae fructus were assessed using quantitative high-performance liquid chromatography. After fractionation using HPD-100 column chromatography, a 30% ethanol fraction was selected based on high-performance liquid chromatography and liquid chromatography with mass spectrometry qualitative analysis to separate and purify. Based on the orientation analysis results, six compounds-deacetyl asperulosidic acid methyl ester, gardenoside, ixoroside, scandoside methyl ester, genipin-1-O-β-d-gentiobioside, and geniposide-were successfully isolated and purified in three to four combined steps from Gardeniae fructus. The purities of these compounds were found by high-performance liquid chromatography analysis to be 97.9, 98.1, 95.5, 96.3, 97.1, and 98.7%, respectively. Moreover, their structures were elucidated by NMR spectroscopy and liquid chromatography with tandem mass spectrometry. The separation process was highly efficient, rapid, and accurate, making it a potential approach for the large-scale production of iridoids in the laboratory and providing several marker compounds for quality control. This procedure may be meaningful for the purification of other natural products used in traditional Chinese medicine. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Determination of Fusarium toxins in functional vegetable milks applying salting-out-assisted liquid-liquid extraction combined with ultra-high-performance liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Hamed, Ahmed M; Arroyo-Manzanares, Natalia; García-Campaña, Ana M; Gámiz-Gracia, Laura

    2017-11-01

    Vegetable milks are considered as functional foods due to their physiological benefits. Although the consumption of these products has significantly increased, they have received little attention in legislation with regard to contaminants. However, they may contain mycotoxins resulting from the use of contaminated raw materials. In this work, ultra-high-performance liquid chromatography tandem mass spectrometry has been proposed for the determination of the most relevant Fusarium toxins (fumonisin B 1 and B 2 , HT-2 and T-2 toxins, zearalenone, deoxynivalenol and fusarenon-X) in different functional beverages based on cereals, legumes and seeds. Sample treatment consisted of a simple salting-out-assisted liquid-liquid extraction with no further clean-up. The method provided limits of quantification between 3.2 and 57.7 µg L -1 , recoveries above 80% and precision with RSD lower than 12%. The method was also applied for studying the occurrence of these mycotoxins in market samples of vegetable functional beverages and deoxynivalenol was found in three oat-based commercial drinks.

  9. Strategy for reduced calibration sets to develop quantitative structure-retention relationships in high-performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Andries, Jan P.M. [University of Professional Education, Department of Life Sciences, P.O. Box 90116, 4800 RA Breda (Netherlands); Claessens, Henk A. [University of Professional Education, Department of Life Sciences, P.O. Box 90116, 4800 RA Breda (Netherlands); Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory of Polymer Chemistry, P.O. Box 513 (Helix, STW 1.35), 5600 MB Eindhoven (Netherlands); Heyden, Yvan Vander [Department of Analytical Chemistry and Pharmaceutical Technology, Vrije Universiteit Brussel-VUB, Laarbeeklaan 103, B-1090 Brussels (Belgium); Buydens, Lutgarde M.C., E-mail: L.Buydens@science.ru.nl [Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands)

    2009-10-12

    In high-performance liquid chromatography, quantitative structure-retention relationships (QSRRs) are applied to model the relation between chromatographic retention and quantities derived from molecular structure of analytes. Classically a substantial number of test analytes is used to build QSRR models. This makes their application laborious and time consuming. In this work a strategy is presented to build QSRR models based on selected reduced calibration sets. The analytes in the reduced calibration sets are selected from larger sets of analytes by applying the algorithm of Kennard and Stone on the molecular descriptors used in the QSRR concerned. The strategy was applied on three QSRR models of different complexity, relating logk{sub w} or log k with either: (i) log P, the n-octanol-water partition coefficient, (ii) calculated quantum chemical indices (QCI), or (iii) descriptors from the linear solvation energy relationship (LSER). Models were developed and validated for 76 reversed-phase high-performance liquid chromatography systems. From the results we can conclude that it is possible to develop log P models suitable for the future prediction of retentions with as few as seven analytes. For the QCI and LSER models we derived the rule that three selected analytes per descriptor are sufficient. Both the dependent variable space, formed by the retention values, and the independent variable space, formed by the descriptors, are covered well by the reduced calibration sets. Finally guidelines to construct small calibration sets are formulated.

  10. Validation of a high-performance liquid chromatography/fluorescence detection method for the simultaneous quantification of fifteen polycyclic aromatic hydrocarbons

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Olsen, I L; Holst, E

    1991-01-01

    A high-performance liquid chromatography/fluorescence method using multiple wavelength shift for simultaneous quantification of different PAH compounds was developed. The new method was superior to the methods of DONG and GREENBERG [J. Liquid Chromatogr. 11, 1887-1905 (1988)] and WISE et al...... that no systematic errors, and only small unsystematic errors, could be demonstrated. Furthermore, the method had a good reproducibility and a high sensitivity....

  11. High Performance Liquid Chromatography Determination of Urinary Hippuric Acid and Benzoic Acid as Indices for Glue Sniffer Urine

    OpenAIRE

    Abdul Rahim Yacob; Mohamad Raizul Zinalibdin

    2010-01-01

    A simple method for the simultaneous determination of hippuric acid and benzoic acid in urine using reversed-phase high performance liquid chromatography was described. Chromatography was performed on a Nova-Pak C18 (3.9 x 150 mm) column with a mobile phase of mixed solution methanol: water: acetic acid (20:80:0.2) and UV detection at 254 nm. The calibration curve was linear within concentration range at 0.125 to 6.0 mg/ml of hippuric acid and benzoic acid. The recovery, ...

  12. Screening of Norharmane from Seven Cyanobacteria by High-performance Liquid Chromatography.

    Science.gov (United States)

    Karan, Tunay; Erenler, Ramazan

    2017-10-01

    Cyanobacteria, including pharmaceutically and medicinally valuable compounds attract the great attention lately. Norharmane (9H-pyrido (3,4-b) indole found in some cyanobacteria revealed a great number of biological effects. Seven cyanobacteria were isolated and identified from Yesilirmak River and Gaziosmanpasa University Campus to determine the norharmane content. Cyanobacteria collected from Tokat, Turkey were isolated and identified by morphologically. Norharmane (9H-pyrido [3,4-b] indole) quantities were presented for seven cyanobacteria, Chroococcus minutus (Kütz.) Nägeli, Geitlerinema carotinosum (Geitler) Anagnostidis, Nostoc linckia Bornet ex Bornet and Flahault, Anabaena oryzae F. E. Fritsch, Oscillatoria limnetica Lemmermann, Phormidium sp . Kützing ex Gomont, and Cylindrospermum sp . Kutzing ex E. Bornet and C. Flahault by high-performance liquid chromatography. The norharmane amount indicated for cyanobacterial culture media altered in a species-dependent kind in the range of 0.81-10.87 μg/g. C. minutus produced the most norharmane among the investigated cyanobacteria as 10.87 μg/g. Cyanobacteria could be an important source of norharmane as well as pharmaceutically valuable compounds. Seven cyanobacteria were isolated and identified from Yesilirmak RiverQuantitative analysis of norharmane was executed on isolated cyanobacteriaFour cyanobecteria species included the norharmane Chroococcus minutus contained the most norharmane (10.87 μg/g). Abbreviations used: HPLC: High performance liquid chromatograph.

  13. Screening of Norharmane from Seven Cyanobacteria by High-performance Liquid Chromatography

    Science.gov (United States)

    Karan, Tunay; Erenler, Ramazan

    2017-01-01

    Background: Cyanobacteria, including pharmaceutically and medicinally valuable compounds attract the great attention lately. Norharmane (9H-pyrido (3,4-b) indole found in some cyanobacteria revealed a great number of biological effects. Objective: Seven cyanobacteria were isolated and identified from Yesilirmak River and Gaziosmanpasa University Campus to determine the norharmane content. Materials and Methods: Cyanobacteria collected from Tokat, Turkey were isolated and identified by morphologically. Norharmane (9H-pyrido [3,4-b] indole) quantities were presented for seven cyanobacteria, Chroococcus minutus (Kütz.) Nägeli, Geitlerinema carotinosum (Geitler) Anagnostidis, Nostoc linckia Bornet ex Bornet and Flahault, Anabaena oryzae F. E. Fritsch, Oscillatoria limnetica Lemmermann, Phormidium sp. Kützing ex Gomont, and Cylindrospermum sp. Kutzing ex E. Bornet and C. Flahault by high-performance liquid chromatography. Results: The norharmane amount indicated for cyanobacterial culture media altered in a species-dependent kind in the range of 0.81–10.87 μg/g. C. minutus produced the most norharmane among the investigated cyanobacteria as 10.87 μg/g. Conclusion: Cyanobacteria could be an important source of norharmane as well as pharmaceutically valuable compounds. SUMMARY Seven cyanobacteria were isolated and identified from Yesilirmak RiverQuantitative analysis of norharmane was executed on isolated cyanobacteriaFour cyanobecteria species included the norharmaneChroococcus minutus contained the most norharmane (10.87 μg/g). Abbreviations used: HPLC: High performance liquid chromatograph. PMID:29142439

  14. Simultaneous determination of iridoid glycosides, phenethylalcohol glycosides and furfural derivatives in Rehmanniae Radix by high performance liquid chromatography coupled with triple-quadrupole mass spectrometry

    DEFF Research Database (Denmark)

    Xu, Jun; Wu, Jie; Zhu, Ling-Ying

    2012-01-01

    In this study, a sensitive and selective method for simultaneously quantifying eight major components (four iridoid glycosides, three phenethylalcohol glycosides and one furfural derivative) of Rehmanniae Radix by high performance liquid chromatography coupled with triple-quadrupole mass spectrom......In this study, a sensitive and selective method for simultaneously quantifying eight major components (four iridoid glycosides, three phenethylalcohol glycosides and one furfural derivative) of Rehmanniae Radix by high performance liquid chromatography coupled with triple-quadrupole mass...

  15. An optimized method for the measurement of acetaldehyde by high-performance liquid chromatography.

    Science.gov (United States)

    Guan, Xiangying; Rubin, Emanuel; Anni, Helen

    2012-03-01

    Acetaldehyde is produced during ethanol metabolism predominantly in the liver by alcohol dehydrogenase and rapidly eliminated by oxidation to acetate via aldehyde dehydrogenase. Assessment of circulating acetaldehyde levels in biological matrices is performed by headspace gas chromatography and reverse phase high-performance liquid chromatography (RP-HPLC). We have developed an optimized method for the measurement of acetaldehyde by RP-HPLC in hepatoma cell culture medium, blood, and plasma. After sample deproteinization, acetaldehyde was derivatized with 2,4-dinitrophenylhydrazine (DNPH). The reaction was optimized for pH, amount of derivatization reagent, time, and temperature. Extraction methods of the acetaldehyde-hydrazone (AcH-DNP) stable derivative and product stability studies were carried out. Acetaldehyde was identified by its retention time in comparison with AcH-DNP standard, using a new chromatography gradient program, and quantitated based on external reference standards and standard addition calibration curves in the presence and absence of ethanol. Derivatization of acetaldehyde was performed at pH 4.0 with an 80-fold molar excess of DNPH. The reaction was completed in 40 minutes at ambient temperature, and the product was stable for 2 days. A clear separation of AcH-DNP from DNPH was obtained with a new 11-minute chromatography program. Acetaldehyde detection was linear up to 80 μM. The recovery of acetaldehyde was >88% in culture media and >78% in plasma. We quantitatively determined the ethanol-derived acetaldehyde in hepatoma cells, rat blood and plasma with a detection limit around 3 μM. The accuracy of the method was volume (70 μl) plasma sampling. An optimized method for the quantitative determination of acetaldehyde in biological systems was developed using derivatization with DNPH, followed by a short RP-HPLC separation of AcH-DNP. The method has an extended linear range, is reproducible and applicable to small-volume sampling of culture

  16. A simple high performance liquid chromatography method for analyzing paraquat in soil solution samples.

    Science.gov (United States)

    Ouyang, Ying; Mansell, Robert S; Nkedi-Kizza, Peter

    2004-01-01

    A high performance liquid chromatography (HPLC) method with UV detection was developed to analyze paraquat (1,1'-dimethyl-4,4'-dipyridinium dichloride) herbicide content in soil solution samples. The analytical method was compared with the liquid scintillation counting (LSC) method using 14C-paraquat. Agreement obtained between the two methods was reasonable. However, the detection limit for paraquat analysis was 0.5 mg L(-1) by the HPLC method and 0.05 mg L(-1) by the LSC method. The LSC method was, therefore, 10 times more precise than the HPLC method for solution concentrations less than 1 mg L(-1). In spite of the high detection limit, the UC (nonradioactive) HPLC method provides an inexpensive and environmentally safe means for determining paraquat concentration in soil solution compared with the 14C-LSC method.

  17. Analyses of Indole Compounds in Sugar Cane (Saccharum officinarum L. Juice by High Performance Liquid Chromatography and Liquid Chromatography-Mass Spectrometry after Solid-Phase Extraction

    Directory of Open Access Journals (Sweden)

    Jean Wan Hong Yong

    2017-03-01

    Full Text Available Simultaneous quantitative analysis of 10 indole compounds, including indole-3-acetic acid (IAA, one of the most important naturally occurring auxins and some of its metabolites, by high performance liquid chromatography (HPLC and liquid chromatography-mass spectrometry (LC-MS after solid-phase extraction (SPE was reported for the first time. The analysis was carried out using a reverse phase HPLC gradient elution, with an aqueous mobile phase (containing 0.1% formic acid modified by methanol. Furthermore, a novel SPE procedure was developed for the pre-concentration and purification of indole compounds using C18 SPE cartridges. The combination of SPE, HPLC, and LC-MS was applied to screen for the indole compounds present in sugar cane (Saccharum officinarum L. juice, a refreshing beverage with various health benefits. Finally, four indole compounds were successfully detected and quantified in sugar cane juice by HPLC, which were further unequivocally confirmed by LC-MS/MS experiments operating in the multiple reaction monitoring (MRM mode.

  18. Analysis of aqueous humour in uveitis by high performance liquid chromatography and sodium dodecyl sulphate-polyacrylamide gel electrophoresis

    NARCIS (Netherlands)

    Murray, P. I.; Hoekzema, R.; Luyendijk, L.; Kijlstra, A.

    1992-01-01

    Aqueous humour from patients with Fuchs' heterochromic cyclitis (FHC) and other types of uveitis was analysed by high performance liquid chromatography (HPLC) and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Using HPLC, the number of peaks and their respective elution times

  19. Simultaneous Determination of Caffeine and Vitamin B6 in Energy Drinks by High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Leacock, Rachel E.; Stankus, John J.; Davis, Julian M.

    2011-01-01

    A high-performance liquid chromatography experiment to determine the concentration of caffeine and vitamin B6 in sports energy drinks has been developed. This laboratory activity, which is appropriate for an upper-level instrumental analysis course, illustrates the standard addition method and simultaneous determination of two species. (Contains 1…

  20. Quantitative structure-retention relationships of pesticides in reversed-phase high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Aschi, Massimiliano; D'Archivio, Angelo Antonio; Maggi, Maria Anna; Mazzeo, Pietro; Ruggieri, Fabrizio

    2007-01-01

    In this paper, a quantitative structure-retention relationships (QSRR) method is employed to predict the retention behaviour of pesticides in reversed-phase high-performance liquid chromatography (HPLC). A six-parameter nonlinear model is developed by means of a feed-forward artificial neural network (ANN) with back-propagation learning rule. Accurate description of the retention factors of 26 compounds including commonly used insecticides, herbicides and fungicides and some metabolites is successfully achieved. In addition to the acetonitrile content, included to describe composition of the water-acetonitrile mobile phase, the octanol-water partition coefficient (from literature) and four quantum chemical descriptors are considered to account for the effect of solute structure on the retention. These are: the total dipole moment, the mean polarizability, the anisotropy of polarizability and a descriptor of hydrogen bonding ability based on the atomic charges on hydrogen bond donor and acceptor chemical functionalities. The proposed nonlinear QSRR model exhibits a high degree of correlation between observed and computed retention factors and a good predictive performance in wide range of mobile phase composition (40-65%, v/v acetonitrile) that supports its application for the prediction of the chromatographic behaviour of unknown pesticides. A multilinear regression model based on the same six descriptors shows a significantly worse predictive capability

  1. Quantitative structure-retention relationships of pesticides in reversed-phase high-performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Aschi, Massimiliano [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy); D' Archivio, Angelo Antonio [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy)]. E-mail: darchivi@univaq.it; Maggi, Maria Anna [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy); Mazzeo, Pietro [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy); Ruggieri, Fabrizio [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy)

    2007-01-23

    In this paper, a quantitative structure-retention relationships (QSRR) method is employed to predict the retention behaviour of pesticides in reversed-phase high-performance liquid chromatography (HPLC). A six-parameter nonlinear model is developed by means of a feed-forward artificial neural network (ANN) with back-propagation learning rule. Accurate description of the retention factors of 26 compounds including commonly used insecticides, herbicides and fungicides and some metabolites is successfully achieved. In addition to the acetonitrile content, included to describe composition of the water-acetonitrile mobile phase, the octanol-water partition coefficient (from literature) and four quantum chemical descriptors are considered to account for the effect of solute structure on the retention. These are: the total dipole moment, the mean polarizability, the anisotropy of polarizability and a descriptor of hydrogen bonding ability based on the atomic charges on hydrogen bond donor and acceptor chemical functionalities. The proposed nonlinear QSRR model exhibits a high degree of correlation between observed and computed retention factors and a good predictive performance in wide range of mobile phase composition (40-65%, v/v acetonitrile) that supports its application for the prediction of the chromatographic behaviour of unknown pesticides. A multilinear regression model based on the same six descriptors shows a significantly worse predictive capability.

  2. High Performance Liquid Chromatography of Vitamin A: A Quantitative Determination.

    Science.gov (United States)

    Bohman, Ove; And Others

    1982-01-01

    Experimental procedures are provided for the quantitative determination of Vitamin A (retinol) in food products by analytical liquid chromatography. Standard addition and calibration curve extraction methods are outlined. (SK)

  3. Validated High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    Purpose: To develop a simple, rapid and sensitive high performance liquid ... response, tailing factor and resolution of six replicate injections was < 3 %. ... Cefadroxil monohydrate, Human plasma, Pharmacokinetics Bioequivalence ... Drug-free plasma was obtained from the local .... Influence of probenicid on the renal.

  4. An Efficient Protocol for Preparation of Gallic Acid from Terminalia bellirica (Gaertn.) Roxb by Combination of Macroporous Resin and Preparative High-Performance Liquid Chromatography.

    Science.gov (United States)

    Zou, Denglang; Chen, Tao; Chen, Chen; Li, Hongmei; Liu, Yongling; Li, Yulin

    2016-08-01

    In this article, macroporous resin column chromatography and preparative high-performance liquid chromatography were applied for preparation of gallic acid from Terminalia bellirica (Gaertn.) Roxb. In the first step, six kinds of resins were investigated by adsorption and desorption tests and AB-8 macroporous resin was selected for the enrichment of gallic acid. As a result, 20 g of gallic acid at a purity of 71% could be separated from 100 g of crude extract in which the content of gallic acid was 16.7% and the recovery of gallic acid reached 85.0%. In the second step, preparative high-performance liquid chromatography was selected to purify gallic acid. As a result, 640 mg of gallic acid at a purity of 99.1% was obtained from 1 g of sample in 35 min. The results demonstrated that macroporous resin coupled with preparative high-performance liquid chromatography was suitable for preparation of gallic acid from T. bellirica (Gaertn.) Roxb. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Thin-layer chromatography coupled with high performance liquid chromatography for determining tetrabromobisphenol A/S and their derivatives in soils.

    Science.gov (United States)

    Liu, Aifeng; Shen, Zhaoshuang; Tian, Yong; Shi, Rongguang; Liu, Yi; Zhao, Zongshan; Xian, Mo

    2017-12-01

    As brominated flame retardants (BFRs), tetrabromobisphenol A/S (TBBPA/S) and their derivatives have raised wide concerns owing to their widely usage, distributions and adverse effects on human health, thus monitoring these BFRs was urgently needed. In this study, a rapid and cost-effective method based on thin-layer chromatography (TLC) sample pre-treatment coupled with high performance liquid chromatography-diode array detector (HPLC-DAD) (UV=214nm) was developed for determining TBBPA/S and their derivatives in soils, including TBBPA, TBBPA bis(allyl ether) (TBBPA-BAE), TBBPA bis(2,3-dibromopropyl ether) (TBBPA-BDBPE), TBBPS bis(allyl ether) (TBBPS-BAE) and TBBPS bis(2,3-dibromopropyl ether) (TBBPS-BDBPE). The method detection limits (MDLs) and the method quantification limits (MQLs) for these BFRs ranged from 0.023 to 0.087μgg -1 dw and 0.076-0.29μgg -1 dw, respectively. The recoveries were 41-108% and both RSD of repeatability and intermediate precision were less than 11%. The developed method presented good performance for analyzing natural soil samples collected from BFRs industrial park, suggesting its great application potential for monitoring environmental TBBPA/S and their derivatives. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. The Determination of Polyethylene Glycol in Untreated Urine Samples by High Performance Liquid Chromatography for Intestinal Permeability Studies

    DEFF Research Database (Denmark)

    Larsen, Elfinn; Pedersen, Walther Batsberg; Philipsen, E.

    1985-01-01

    Polyethylene glycol in urine samples has been investigated by high performance liquid chromatography. The molecular weights ranged from 634 to 1338. The urine samples were applied to the chromatographic system without any pre-treatment. For samples with a concentration of 0.2% polyethylene glycol...

  7. Ultra Performance Liquid Chromatography Tandem Mass ...

    African Journals Online (AJOL)

    NICOLAAS

    drugs alone.16. After a single oral dose of 120–800 mg of NTB in healthy sub- jects in a fasting state the peak plasma NTB concentration (tmax) was found to be 4–7 h, with a half-life of approximately 9–17 h.17 ... performance liquid chromatography mass spectrometry/mass .... to the likely biological plasma constituents.

  8. High-performance liquid chromatography for determination of α-tocopherol in vegetables

    Directory of Open Access Journals (Sweden)

    Marcin Horbowicz

    2013-12-01

    Full Text Available A simple method for the determination of α-tocopherol in vegetables is described. The procedure consists of the following steps: saponification, extraction, silica-column clean-up, and high-performance liquid chromatography. Elution time for D, L-α-tocopherol was 9.0 min using a Zorbax Sil (250 x 4.6 mm column and an isocratic mobile phase of hexane-methanol (99.3 + 0.7, with a flow rate of 1 ml/min, and detection at 292 nm using a variable UV detector. The average recovery of α-tocopherol was 91.2%, and the minimum detectable amount was 0.1 mg/100 g of fresh vegetable tissue. This method is comparable to gas-chromatographic determination of α-tocopherol, but has fewer analytical steps and gives more reproducible results.

  9. Simultaneous determination of atorvastatin and valsartan in human plasma by solid-based disperser liquid-liquid microextraction followed by high-performance liquid chromatography-diode array detection.

    Science.gov (United States)

    Farajzadeh, Mir Ali; Khorram, Parisa; Pazhohan, Azar

    2016-04-01

    A simple, sensitive, and efficient method has been developed for simultaneous estimation of valsartan and atorvastatin in human plasma by combination of solid-based dispersive liquid-liquid microextraction and high performance liquid chromatography-diode array detection. In the proposed method, 1,2-dibromoethane (extraction solvent) is added on a sugar cube (as a solid disperser) and it is introduced into plasma sample containing the analytes. After manual shaking and centrifugation, the resultant sedimented phase is subjected to back extraction into a small volume of sodium hydrogen carbonate solution using air-assisted liquid-liquid microextraction. Then the cloudy solution is centrifuged and the obtained aqueous phase is transferred into a microtube and analyzed by the separation system. Under the optimal conditions, extraction recoveries are obtained in the range of 81-90%. Calibration curves plotted in drug-free plasma sample are linear in the ranges of 5-5000μgL(-1) for valsartan and 10-5000μgL(-1) for atorvastatin with the coefficients of determination higher than 0.997. Limits of detection and quantification of the studied analytes in plasma sample are 0.30-2.6 and 1.0-8.2μgL(-1), respectively. Intra-day (n=6) and inter-days (n=4) precisions of the method are satisfactory with relative standard deviations less than 7.4% (at three levels of 10, 500, and 2000μgL(-1), each analyte). These data suggest that the method can be successfully applied to determine trace amounts of valsartan and atorvastatin in human plasma samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. RECENT ADVANCES IN ULTRA-HIGH PERFORMANCE LIQUID CHROMATOGRAPHY FOR THE ANALYSIS OF TRADITIONAL CHINESE MEDICINE

    Science.gov (United States)

    Huang, Huilian; Liu, Min; Chen, Pei

    2014-01-01

    Traditional Chinese medicine has been widely used for the prevention and treatment of various diseases for thousands of years in China. Ultra-high performance liquid chromatography (UHPLC) is a relatively new technique offering new possibilities. This paper reviews recent developments in UHPLC in the separation and identification, fingerprinting, quantification, and metabolism of traditional Chinese medicine. Recently, the combination of UHPLC with MS has improved the efficiency of the analysis of these materials. PMID:25045170

  11. Burn-up measurements on nuclear reactor fuels using high performance liquid chromatography

    International Nuclear Information System (INIS)

    Sivaraman, N.; Subramaniam, S.; Srinivasan, T.G.; Vasudeva Rao, P.R.

    2002-01-01

    Burn-up measurements on thermal as well as fast reactor fuels were carried out using high performance liquid chromatography (HPLC). A column chromatographic technique using di-(2-ethylhexyl) phosphoric acid (HDEHP) coated column was employed for the isolation of lanthanides from uranium, plutonium and other fission products. Ion-pair HPLC was used for the separation of individual lanthanides. The atom percent fissions were calculated from the concentrations of the lanthanide (neodymium in the case of thermal reactor and lanthanum for the fast reactor fuels) and from uranium and plutonium contents of the dissolver solutions. The HPLC method was also used for determining the fractional fissions from uranium and plutonium for the thermal reactor fuel. (author)

  12. Characterization of phenolic amides from cortex lycii by ultra high-performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry

    Science.gov (United States)

    High performance liquid chromatography (UPLC) and flow injection electrospray ionization with ion trap mass spectrometry (FIMS) fingerprints combined with the principal component analysis (PCA) were examined for their potential in differentiating commercial organic and conventional sage samples. The...

  13. Analysis by high-performance liquid chromatography of teucrin A in beverages flavoured with an extract of Teucrium chamaedrys L.

    Science.gov (United States)

    Bosisio, E; Giavarini, F; Dell'Agli, M; Galli, G; Galli, C L

    2004-05-01

    Due to its liver toxicity, the medicinal use of germander (Teucrium chamaedrys L.) was banned in some countries. Nevertheless, alcoholic extracts are still permitted as flavour ingredients since they are fundamental in providing a bitter aromatic taste. Teucrin A represents the substance of major concern regarding the potential toxicity of germander. Hence, teucrin A represents the best analytical and toxicological marker of alcoholic extracts of T. chamaedrys. A sensitive high-performance liquid chromatography method to detect teucrin A in beverages is reported. Teucrin A was prepared by isolation from the plant extract using column chromatography and crystallization. The identity and purity (99%) were established by melting point, nuclear magnetic resonance and liquid chromatography-mass spectrometry. The high-performance liquid chromatography procedure was validated and its intra- and interday performance was established (relative standard deviation beverages not containing T. chamaedrys spiked with a range of concentrations of teucrin A. The limit of detection was 0.1 ppm and the limit of quantification was 0.3 ppm. Teucrin A accounted for about 70% of the neo-clerodane diterpenoids found in the total extract of a specimen of T. chamaedrys. The content (+/- standard deviation) in 18 batches of different geographical origin was 2338 +/- 740 ppm, per cent coefficient of variation = 32, minimum-maximum = 999 - 3445 ppm. The mean level of teucrin A in 10 bottles of the same brand was 6.1 +/- 0.8 ppm, per cent coefficient of variation = 12. In 10 different brands found on the Italian market, the content of teucrin A ranged from not detectable to 10 ppm.

  14. Determination of Polycyclic Aromatic Hydrocarbons in Automobile Exhaust by Means of High-Performance Liquid Chromatography with Fluorescence Detection

    DEFF Research Database (Denmark)

    Nielsen, Tom

    1979-01-01

    A chromatographic method has been developed and applied to the determination of polycyclic aromatic hydrocarbons (PAHs) in particulate matter in automobile exhaust, in petrols, and in crankcase oils. The PAHs were purified from other organic compounds by thin-layer chromatography, separated by high......-performance liquid chromatography, and measured by means of on-line fluorescence detection. The identities of the PAHs were verified by comparing the emission spectra obtained by a stop-flow technique with those of standard PAHs...

  15. Binary Solvents Dispersive Liquid-Liquid Microextraction (BS-DLLME) Method for Determination of Tramadol in Urine Using High-Performance Liquid Chromatography.

    Science.gov (United States)

    Kiarostami, Vahid; Rouini, Mohamad-Reza; Mohammadian, Razieh; Lavasani, Hoda; Ghazaghi, Mehri

    2014-02-03

    Tramadol is an opioid, synthetic analog of codeine and has been used for the treatment of acute or chronic pain may be abused. In this work, a developed Dispersive liquid liquid microextraction (DLLME) as binary solvents-based dispersive liquid-liquid microextraction (BS-DLLME) combined with high performance liquid chromatography (HPLC) with fluorescence detection (FD) was employed for determination of tramadol in the urine samples. This procedure involves the use of an appropriate mixture of binary extraction solvents (70 μL CHCl3 and 30 μL ethyl acetate) and disperser solvent (600 μL acetone) for the formation of cloudy solution in 5 ml urine sample comprising tramadol and NaCl (7.5%, w/v). After centrifuging, the small droplets of extraction solvents were precipitated. In the final step, the HPLC with fluorescence detection was used for determination of tramadol in the precipitated phase. Various factors on the efficiency of the proposed procedure were investigated and optimized. The detection limit (S/N = 3) and quantification limit (S/N = 10) were found 0.2 and 0.9 μg/L, respectively. The relative standard deviations (RSD) for the extraction of 30 μg L of tramadol was found 4.1% (n = 6). The relative recoveries of tramadol from urine samples at spiking levels of 10, 30 and 60 μg/L were in the range of 95.6 - 99.6%. Compared with other methods, this method provides good figures of merit such as good repeatability, high extraction efficiency, short analysis time, simple procedure and can be used as microextraction technique for routine analysis in clinical laboratories.

  16. Highly Sensitive Determination of 2,4,6-Trinitrotoluene and Related Byproducts Using a Diol Functionalized Column for High Performance Liquid Chromatography

    NARCIS (Netherlands)

    Gümüscü, B.; Erdogan, Zeynep; Guler, Mustafa O.; Tekinay, Turgay

    2016-01-01

    In this work, a new detection method for complete separation of 2,4,6-trinitrotoluene (TNT); 2,4-dinitrotoluene (2,4-DNT); 2,6-dinitrotoluene (2,6-DNT); 2-aminodinitrotoluene (2-ADNT) and 4-aminodinitrotoluene (4-ADNT) molecules in high-performance liquid-chromatography (HPLC) with UV sensor has

  17. Development of high performance liquid chromatography for rapid determination of burn-up of nuclear fuels

    International Nuclear Information System (INIS)

    Joseph, M.; Karunasagar, D.; Saha, B.

    1996-01-01

    Burn-up an important parameter during evaluation of the performance of any nuclear fuel. Among the various techniques available, the preferred one for its determination is based on accurate measurement of a suitable fission product monitor and the residual heavy elements. Since isotopes of rare earth elements are generally used as burn-up monitors, conditions were standardized for rapid separation (within 15 minutes) of light rare earths using high performance liquid chromatography based on either anion exchange (Partisil 10 SAX) in methanol-nitric acid medium or by cation exchange on a reverse phase column (Spherisorb 5-ODS-2 or Supelcosil LC-18) dynamically modified with 1-octane sulfonate or camphor-10-sulfonic acid (β). Both these methods were assessed for separation of individual fission product rare earths from their mixtures. A new approach has been examined in detail for rapid assay of neodymium, which appears promising for faster and accurate measurement of burn-up. (author)

  18. Supercritical fluid chromatography versus high performance liquid chromatography for enantiomeric and diastereoisomeric separations on coated polysaccharides-based stationary phases: Application to dihydropyridone derivatives.

    Science.gov (United States)

    Hoguet, Vanessa; Charton, Julie; Hecquet, Paul-Emile; Lakhmi, Chahinaze; Lipka, Emmanuelle

    2018-05-11

    For analytical applications, SFC has always remained in the shadow of LC. Analytical enantioseparation of eight dihydropyridone derivatives, was run in both High Performance Liquid Chromatography and Supercritical Fluid Chromatography. Four polysaccharide based chiral stationary phases namely amylose and cellulose tris(3, 5-dimethylphenylcarbamate), amylose tris((S)-α-phenylethylcarbamate) and cellulose tris(4-methylbenzoate) with four mobile phases consisted of either n-hexane/ethanol or propan-2-ol (80:20 v:v) or carbon dioxide/ethanol or propan-2-ol (80:20 v:v) mixtures were investigated under same operatory conditions (temperature and flow-rate). The elution strength, enantioselectivity and resolution were compared in the two methodologies. For these compounds, for most of the conditions, HPLC afforded shorter retention times and a higher resolution than SFC. HPLC appears particularly suitable for the separation of the compounds bearing two chiral centers. For instance compound 7 was baseline resolved on OD-H CSP under n-Hex/EtOH 80/20, with resolution values equal to 2.98, 1.55, 4.52, between the four stereoisomers in less than 17 min, whereas in SFC, this latter is not fully separated in 23 min under similar eluting conditions. After analytical screenings, the best conditions were transposed to semi-preparative scale. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Determination of diacylhydrazines-type insect growth regulator JS-118 residues in cabbage and soil by high performance liquid chromatography with DAD detection.

    Science.gov (United States)

    Hu, J-Y; Deng, Z-B; Qin, D-M

    2009-12-01

    JS-118 is a diacylhydrazines-type insect growth regulator used extensively in China now. An analytical method for residues determination of JS-118 in cabbage and soil samples by high performance liquid chromatography with DAD detection was established and optimized. Primary secondary amine solid phase extraction cartridge was used for sample preparation. Mean recoveries for the analyte ranged from 96.6% to 107.0% with CV value less than 4.7%. The limit of quantification is 0.01 mg/kg. Direct confirmation of JS-118 residues in samples was realized by high performance liquid chromatography-mass spectrometry. The proposed method is simple, rapid and reliable to perform and could be utilized for monitoring of pesticides residues.

  20. Separation and Quantitation of Polyamines in Plant Tissue by High Performance Liquid Chromatography of Their Dansyl Derivatives

    Science.gov (United States)

    Smith, Mary A.; Davies, Peter J.

    1985-01-01

    High performance liquid chromatography in combination with fluorescence spectrophotometry can be used to separate and quantitate polyamines (putrescine, cadaverine, spermidine, spermine), prepared as their dansyl derivatives, from plant tissue. The procedure gives sensitive and consistent results for polyamine determinations in plant tissue. In a standard mixture, the minimal detection level was less than 1 picomole of polyamines. PMID:16664216

  1. [Qualitative and quantitative analysis of amygdalin and its metabolite prunasin in plasma by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry].

    Science.gov (United States)

    Gao, Meng; Wang, Yuesheng; Wei, Huizhen; Ouyang, Hui; He, Mingzhen; Zeng, Lianqing; Shen, Fengyun; Guo, Qiang; Rao, Yi

    2014-06-01

    A method was developed for the determination of amygdalin and its metabolite prunasin in rat plasma after intragastric administration of Maxing shigan decoction. The analytes were identified by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and quantitatively determined by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry. After purified by liquid-liquid extraction, the qualitative analysis of amygdalin and prunasin in the plasma sample was performed on a Shim-pack XR-ODS III HPLC column (75 mm x 2.0 mm, 1.6 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on a Triple TOF 5600 quadrupole time of flight mass spectrometer. The quantitative analysis of amygdalin and prunasin in the plasma sample was performed by separation on an Agilent C18 HPLC column (50 mm x 2.1 mm, 1.7 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on an AB Q-TRAP 4500 triple quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operated in negative ion mode and multiple-reaction monitoring (MRM) mode. The qualitative analysis results showed that amygdalin and its metabolite prunasin were detected in the plasma sample. The quantitative analysis results showed that the linear range of amygdalin was 1.05-4 200 ng/mL with the correlation coefficient of 0.999 0 and the linear range of prunasin was 1.25-2 490 ng/mL with the correlation coefficient of 0.997 0. The method had a good precision with the relative standard deviations (RSDs) lower than 9.20% and the overall recoveries varied from 82.33% to 95.25%. The limits of detection (LODs) of amygdalin and prunasin were 0.50 ng/mL. With good reproducibility, the method is simple, fast and effective for the qualitative and quantitative analysis of the amygdalin and prunasin in plasma sample of rats which were administered by Maxing shigan decoction.

  2. Quantification of sulphur amino acids by ultra-high performance liquid chromatography in aquatic invertebrates.

    Science.gov (United States)

    Thera, Jennifer C; Kidd, Karen A; Dodge-Lynch, M Elaine; Bertolo, Robert F

    2017-12-15

    We examined the performance of an ultra-high performance liquid chromatography method to quantify protein-bound sulphur amino acids in zooplankton. Both cysteic acid and methionine sulfone were linear from 5 to 250 pmol (r 2  = 0.99), with a method detection limit of 13 pmol and 9 pmol, respectively. Although there was no matrix effect on linearity, adjacent peaks and co-eluting noise from the invertebrate proteins increased the detection limits when compared to common standards. Overall, performance characteristics were reproducible and accurate, and provide a means for quantifying sulphur amino acids in aquatic invertebrates, an understudied group. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Air-assisted liquid-liquid microextraction integrated with QuEChERS for determining endocrine-disrupting compounds in fish by high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Luo, Zhoufei; Lu, Jing; Li, Haipu; Tu, Yi; Wan, Yuehao; Yang, Zhaoguang

    2018-09-15

    A new, sensitive, and rapid method based on the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) approach and air-assisted liquid-liquid microextraction (AALLME) technology was developed for the determination of 20 endocrine-disrupting compounds (EDCs) in fish by high-performance liquid chromatography-tandem mass spectrometry. The method first integrates AALLME into QuEChERS to achieve clean-up and enrichment of the EDCs in one step. A self-made glass tube was enfolded with plasticine to withstand the high centrifugal force. The established method was developed by optimization of the parameters. High linearities (R 2  > 0.9924) and recoveries (78.2-118.6%) at three spiked levels (5, 10, and 20 ng g -1 ), and low relative standard deviation values (1.1-14.5%) and limits of detection (0.03-0.80 ng g -1 ) were obtained. The method comparison shows that the proposed method is superior as it involves less organic solvent usage, simple operation and high efficiency. This method was successfully applied to different fishes for analyzing EDCs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Quantitative determination of acetaminophen, phenylephrine and carbinoxamine in tablets by high-performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Carina de A. Bastos

    2009-01-01

    Full Text Available An alternative methodology for analysis of acetaminophen (Ace, phenylephrine (Phe and carbinoxamine (Car in tablets by ion-pair reversed phase high performance liquid chromatography was validated. The pharmaceutical preparations were analyzed by using a C18 column (5 μm, 300 mm, 3.9 mm and mobile phase consisting of 60% methanol and 40% potassium monobasic phosphate aqueous solution (62.46 mmol L-1 added with 1 mL phosphoric acid, 0.50 mL triethylamine and 0.25 g sodium lauryl sulfate. Isocratic analysis was performed under direct UV detection at 220 nm for Phe and Car and at 300 nm for Ace within 5 min.

  5. Standardization of heparins by means of high performance liquid chromatography equipped with a low angle laser light scattering detector

    NARCIS (Netherlands)

    Hennink, W.E.; van den Berg, J.W.A.; Feijen, Jan

    1987-01-01

    This study shows that HPLC-LALLS (high performance liquid chromatography with a light-scattering detector) is a convenient and reliable method for the characterization of standard heparin samples, provided that polyelectrolyte artefacts are suppressed by a suitable dialysis procedure. The method has

  6. Simultaneous determination of nitroimidazoles, benzimidazoles, and chloramphenicol components in bovine milk by ultra-high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Wang, Yuanyuan; Li, Xiaowei; Zhang, Zhiwen; Ding, Shuangyang; Jiang, Haiyang; Li, Jiancheng; Shen, Jianzhong; Xia, Xi

    2016-02-01

    A sensitive, confirmatory ultra-high performance liquid chromatography-tandem mass spectrometric method was developed and validated to detect 23 veterinary drugs and metabolites (nitroimidazoles, benzimidazoles, and chloramphenicol components) in bovine milk. Compounds of interest were sequentially extracted from milk with acetonitrile and basified acetonitrile using sodium chloride to induce liquid-liquid partition. The extract was purified on a mixed mode solid-phase extraction cartridge. Using rapid polarity switching in electrospray ionization, a single injection was capable of detecting both positively and negatively charged analytes in a 9 min chromatography run time. Recoveries based on matrix-matched calibrations and isotope labeled internal standards for milk ranged from 51.7% to 101.8%. The detection limits and quantitation limits of the analytical method were found to be within the range of 2-20 ng/kg and 5-50 ng/kg, respectively. The recommended method is simple, specific, and reliable for the routine monitoring of nitroimidazoles, benzimidazoles, and chloramphenicol components in bovine milk samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Analysis of native human plasma proteins and haemoglobin for the presence of bityrosine by high-performance liquid chromatography

    DEFF Research Database (Denmark)

    Daneshvar, B; Frandsen, H; Dragsted, L O

    1997-01-01

    fluorescent substance, bityrosine. High-performance liquid chromatography (HPLC) analysis of acid hydrolyzed serum albumin after oxidation with peroxidase/H2O2 or with Cu++/H2O2 showed that bityrosine had been formed whereas oxidation of this protein with Fe(III)/ascorbate did not result in the formation...

  8. UHPLC: The Greening Face of Liquid Chromatography.

    Science.gov (United States)

    Cielecka-Piontek, Judyta; Zalewski, Przemysław; Jelińska, Anna; Garbacki, Piotr

    2013-01-01

    Pharmaceutical analysis based on chromatographic separation is an important part of studies aimed at developing routine quality analysis of drugs. High-performance liquid chromatography (HPLC) is one of the main analytical techniques recommended for drug analysis. Although it meets many criteria vital for analysis, it is time-consuming and uses a relatively high amount of organic solvents compared to other analytical techniques. Recently, Ultra-high-performance liquid chromatography (UHPLC) has been frequently proposed as an alternative to HPLC, which means introducing an environment-friendly approach to drug analysis achieved by reducing the consumption of solvents. It also offers greater chromatographic resolution and higher sensitivity as well as requiring less time due to faster analysis. This review focuses on the basics of UHPLC, compares that technique with HPLC and discusses the possibilities of applying UHPLC for the analysis of different pharmaceuticals and biopharmaceuticals.

  9. Fast and sensitive analysis of beta blockers by ultra-high-performance liquid chromatography coupled with ultra-high-resolution TOF mass spectrometry.

    Science.gov (United States)

    Tomková, Jana; Ondra, Peter; Kocianová, Eva; Václavík, Jan

    2017-07-01

    This paper presents a method for the determination of acebutolol, betaxolol, bisoprolol, metoprolol, nebivolol and sotalol in human serum by liquid-liquid extraction and ultra-high-performance liquid chromatography coupled with ultra-high-resolution TOF mass spectrometry. After liquid-liquid extraction, beta blockers were separated on a reverse-phase analytical column (Acclaim RS 120; 100 × 2.1 mm, 2.2 μm). The total run time was 6 min for each sample. Linearity, limit of detection, limit of quantification, matrix effects, specificity, precision, accuracy, recovery and sample stability were evaluated. The method was successfully applied to the therapeutic drug monitoring of 108 patients with hypertension. This method was also used for determination of beta blockers in 33 intoxicated patients. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Rapid determination of some psychotropic drugs in complex matrices by tandem dispersive liquid-liquid microextraction followed by high performance liquid chromatography.

    Science.gov (United States)

    Asghari, Alireza; Fahimi, Ebrahim; Bazregar, Mohammad; Rajabi, Maryam; Boutorabi, Leila

    2017-05-01

    Simple and rapid determinations of some psychotropic drugs in some pharmaceutical wastewater and human plasma samples were successfully accomplished via the tandem dispersive liquid-liquid microextraction combined with high performance liquid chromatography-ultraviolet detection (TDLLME-HPLC-UV). TDLLME of the three psychotropic drugs clozapine, chlorpromazine, and thioridazine was easily performed through two consecutive dispersive liquid-liquid microextractions. By performing this convenient method, proper sample preconcentrations and clean-ups were achieved in just about 7min. In order to achieve the best extraction efficiency, the effective parameters involved were optimized. The optimal experimental conditions consisted of 100μL of CCl 4 (as the extraction organic solvent), and the pH values of 13 and 2 for the donor and acceptor phases, respectively. Under these optimum experimental conditions, the proposed TDLLME-HPLC-UV technique provided a good linearity in the range of 5-3000ngmL -1 for the three psychotropic drugs with the correlation of determinations (R 2 s) higher than 0.996. The limits of quantification (LOQs) and limits of detection (LODs) obtained were 5.0ngmL -1 and 1.0-1.5ngmL -1 , respectively. Also the proper enrichment factors (EFs) of 96, 99, and 88 for clozapine, chlorpromazine, and thioridazine, respectively, and good extraction repeatabilities (relative standard deviations below 9.3%, n=5) were obtained. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Simultaneous determination of caffeine, paracetamol, and ibuprofen in pharmaceutical formulations by high-performance liquid chromatography with UV detection and by capillary electrophoresis with conductivity detection.

    Science.gov (United States)

    Cunha, Rafael R; Chaves, Sandro C; Ribeiro, Michelle M A C; Torres, Lívia M F C; Muñoz, Rodrigo A A; Dos Santos, Wallans T P; Richter, Eduardo M

    2015-05-01

    Paracetamol, caffeine and ibuprofen are found in over-the-counter pharmaceutical formulations. In this work, we propose two new methods for simultaneous determination of paracetamol, caffeine and ibuprofen in pharmaceutical formulations. One method is based on high-performance liquid chromatography with diode-array detection and the other on capillary electrophoresis with capacitively coupled contactless conductivity detection. The separation by high-performance liquid chromatography with diode-array detection was achieved on a C18 column (250×4.6 mm(2), 5 μm) with a gradient mobile phase comprising 20-100% acetonitrile in 40 mmol L(-1) phosphate buffer pH 7.0. The separation by capillary electrophoresis with capacitively coupled contactless conductivity detection was achieved on a fused-silica capillary (40 cm length, 50 μm i.d.) using 10 mmol L(-1) 3,4-dimethoxycinnamate and 10 mmol L(-1) β-alanine with pH adjustment to 10.4 with lithium hydroxide as background electrolyte. The determination of all three pharmaceuticals was carried out in 9.6 min by liquid chromatography and in 2.2 min by capillary electrophoresis. Detection limits for caffeine, paracetamol and ibuprofen were 4.4, 0.7, and 3.4 μmol L(-1) by liquid chromatography and 39, 32, and 49 μmol L(-1) by capillary electrophoresis, respectively. Recovery values for spiked samples were between 92-107% for both proposed methods. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Utilization of highly robust and selective crosslinked polymeric ionic liquid-based sorbent coatings in direct-immersion solid-phase microextraction and high-performance liquid chromatography for determining polar organic pollutants in waters.

    Science.gov (United States)

    Pacheco-Fernández, Idaira; Najafi, Ali; Pino, Verónica; Anderson, Jared L; Ayala, Juan H; Afonso, Ana M

    2016-09-01

    Several crosslinked polymeric ionic liquid (PIL)-based sorbent coatings of different nature were prepared by UV polymerization onto nitinol wires. They were evaluated in a direct-immersion solid-phase microextraction (DI-SPME) method in combination with high-performance liquid chromatography (HPLC) and diode array detection (DAD). The studied PIL coatings contained either vinyl alkyl or vinylbenzyl imidazolium-based (ViCnIm- or ViBCnIm-) IL monomers with different anions, as well as different dicationic IL crosslinkers. The analytical performance of these PIL-based SPME coatings was firstly evaluated for the extraction of a group of 10 different model analytes, including hydrocarbons and phenols, while exhaustively comparing the performance with commercial SPME fibers such as polydimethylsyloxane (PDMS), polyacrylate (PA) and polydimethylsiloxane/divinylbenzene (PDMS/DVB), and using all fibers under optimized conditions. Those fibers exhibiting a high selectivity for polar compounds were selected to carry out an analytical method for a group of 5 alkylphenols, including bisphenol-A (BPA) and nonylphenol (n-NP). Under optimum conditions, average relative recoveries of 108% and inter-day precision values (3 non-consecutive days) lower than 19% were obtained for a spiked level of 10µgL(-1). Correlations coefficients for the overall method ranged between 0.990 and 0.999, and limits of detection were down to 1µgL(-1). Tap water, river water, and bottled water were analyzed to evaluate matrix effects. Comparison with the PA fiber was also performed in terms of analytical performance. Partition coefficients (logKfs) of the alkylphenols to the SPME coating varied from 1.69 to 2.45 for the most efficient PIL-based fiber, and from 1.58 to 2.30 for the PA fiber. These results agree with those obtained by the normalized calibration slopes, pointing out the affinity of these PILs-based coatings. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Separation of anionic oligosaccharides by high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Green, E.D.; Baenziger, J.U.

    1986-01-01

    The authors have developed methods for rapid fractionation of anionic oligosaccharides containing sulfate and/or sialic acid moieties by high-performance liquid chromatography (HPLC). Ion-exchange HPLC on amine-bearing columns (Micropak AX-10 and AX-5) at pH 4.0 is utilized to separate anionic oligosaccharides bearing zero, one, two, three, or four charges, independent of the identity of the anionic moieties (sulfate and/or sialic acid). Ion-exchange HPLC at pH 1.7 allows separation of neutral, mono-, di-, and tetrasialylated, monosulfated, and disulfated oligosaccharides. Oligosaccharides containing three sialic acid residues and those bearing one each of sulfate and sialic acid, however, coelute at pH 1.7. Since the latter two oligosaccharide species separate at pH 4.0, analysis at pH 4.0 followed by analysis at pH 1.7 can be utilized to completely fractionate complex mixtures of sulfated and sialylated oligosaccharides. Ion-suppression amine adsorption HPLC has previously been shown to separate anionic oligosaccharides on the basis of net carbohydrate content (size). In this study they demonstrate the utility of ion-suppression amine adsorption HPLC for resolving sialylated oligosaccharide isomers which differ only in the linkages of sialic acid residues (α2,3 vs α2,6) and/or location of α2,3- and α2,6-linked sialic acid moieties on the peripheral branches of oligosaccharides. These two methods can be used in tandem to separate oligosaccharides, both analytically and preparatively, based on their number, types, and linkages of anionic moieties

  14. Simultaneous Determination of Food-Related Biogenic Amines and Precursor Amino Acids Using in Situ Derivatization Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction by Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry.

    Science.gov (United States)

    He, Yongrui; Zhao, Xian-En; Wang, Renjun; Wei, Na; Sun, Jing; Dang, Jun; Chen, Guang; Liu, Zhiqiang; Zhu, Shuyun; You, Jinmao

    2016-11-02

    A simple, rapid, sensitive, selective, and environmentally friendly method, based on in situ derivatization ultrasound-assisted dispersive liquid-liquid microextraction (in situ DUADLLME) coupled with ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) using multiple reaction monitoring (MRM) mode has been developed for the simultaneous determination of food-related biogenic amines and amino acids. A new mass-spectrometry-sensitive derivatization reagent 4'-carbonyl chloride rosamine (CCR) was designed, synthesized, and first reported. Parameters and conditions of in situ DUADLLME and UHPLC-MS/MS were optimized in detail. Under the optimized conditions, the in situ DUADLLME was completed speedily (within 1 min) with high derivatization efficiencies (≥98.5%). With the cleanup and concentration of microextraction step, good analytical performance was obtained for the analytes. The results showed that this method was accurate and practical for quantification of biogenic amines and amino acids in common food samples (red wine, beer, wine, cheese, sausage, and fish).

  15. Simultaneous determination of furfural and its degradation products, furoic acid and maleic acid, in transformer oil by the reversed-phase vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography.

    Science.gov (United States)

    Wang, Yifan; Li, Haiyan; Yang, Zhen; Zhang, Weijie; Hua, Jia

    2017-12-01

    To explore why the use of furfural as a transformer oil-paper insulation aging characteristic is problematic in real world application, we developed a method for the simultaneous determination of furfural, furoic acid, and maleic acid in transformer oil by reversed-phase vortex-assisted liquid-liquid microextraction combined with high-performance liquid chromatography. The conditions for the proposed method were optimized, and the obtained extract can be directly analyzed by high-performance liquid chromatography. The detection limits (signal-to-noise ratio = 3) of the method ranged from 1.0 to 4.6 μg/L, the enrichment factors for furfural, furoic acid, maleic acid, and fumaric acid were 4.6, 25.1, 15.6, and 17.5, respectively, and the recovery rates for three analytes (fumaric acid was undetected) range from 82.1 to 106.2%. The contents of furfural, furoic acid, and maleic acid resulted from accelerated aging of transformer insulation oil-paper were measured using the present method for the first time, and the aging samples were analyzed by liquid chromatography with mass spectrometry for the identification of furoic acid and maleic acid in the aging transformer oil samples. Using the optimal method, the target products of samples at different aging time were tracked and measured. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Simultaneous determination of phenolic compounds in Equisetum palustre L. by ultra high performance liquid chromatography with tandem mass spectrometry combined with matrix solid-phase dispersion extraction.

    Science.gov (United States)

    Wei, Zuofu; Pan, Youzhi; Li, Lu; Huang, Yuyang; Qi, Xiaolin; Luo, Meng; Zu, Yuangang; Fu, Yujie

    2014-11-01

    A method based on matrix solid-phase dispersion extraction followed by ultra high performance liquid chromatography with tandem mass spectrometry is presented for the extraction and determination of phenolic compounds in Equisetum palustre. This method combines the high efficiency of matrix solid-phase dispersion extraction and the rapidity, sensitivity, and accuracy of ultra high performance liquid chromatography with tandem mass spectrometry. The influential parameters of the matrix solid-phase dispersion extraction were investigated and optimized. The optimized conditions were as follows: silica gel was selected as dispersing sorbent, the ratio of silica gel to sample was selected to be 2:1 (400/200 mg), and 8 mL of 80% methanol was used as elution solvent. Furthermore, a fast and sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed for the determination of nine phenolic compounds in E. palustre. This method was carried out within <6 min, and exhibited satisfactory linearity, precision, and recovery. Compared with ultrasound-assisted extraction, the proposed matrix solid-phase dispersion procedure possessed higher extraction efficiency, and was more convenient and time saving with reduced requirements on sample and solvent amounts. All these results suggest that the developed method represents an excellent alternative for the extraction and determination of active components in plant matrices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Sensitivity enhancement by chromatographic peak concentration with ultra-high performance liquid chromatography-nuclear magnetic resonance spectroscopy for minor impurity analysis.

    Science.gov (United States)

    Tokunaga, Takashi; Akagi, Ken-Ichi; Okamoto, Masahiko

    2017-07-28

    High performance liquid chromatography can be coupled with nuclear magnetic resonance (NMR) spectroscopy to give a powerful analytical method known as liquid chromatography-nuclear magnetic resonance (LC-NMR) spectroscopy, which can be used to determine the chemical structures of the components of complex mixtures. However, intrinsic limitations in the sensitivity of NMR spectroscopy have restricted the scope of this procedure, and resolving these limitations remains a critical problem for analysis. In this study, we coupled ultra-high performance liquid chromatography (UHPLC) with NMR to give a simple and versatile analytical method with higher sensitivity than conventional LC-NMR. UHPLC separation enabled the concentration of individual peaks to give a volume similar to that of the NMR flow cell, thereby maximizing the sensitivity to the theoretical upper limit. The UHPLC concentration of compound peaks present at typical impurity levels (5.0-13.1 nmol) in a mixture led to at most three-fold increase in the signal-to-noise ratio compared with LC-NMR. Furthermore, we demonstrated the use of UHPLC-NMR for obtaining structural information of a minor impurity in a reaction mixture in actual laboratory-scale development of a synthetic process. Using UHPLC-NMR, the experimental run times for chromatography and NMR were greatly reduced compared with LC-NMR. UHPLC-NMR successfully overcomes the difficulties associated with analyses of minor components in a complex mixture by LC-NMR, which are problematic even when an ultra-high field magnet and cryogenic probe are used. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Deep eutectic solvent-based ultrasound-assisted dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography for the determination of ultraviolet filters in water samples.

    Science.gov (United States)

    Wang, Huazi; Hu, Lu; Liu, Xinya; Yin, Shujun; Lu, Runhua; Zhang, Sanbing; Zhou, Wenfeng; Gao, Haixiang

    2017-09-22

    In the present study, a simple and rapid sample preparation method designated ultrasound-assisted dispersive liquid-liquid microextraction based on a deep eutectic solvent (DES) followed by high-performance liquid chromatography with ultraviolet (UV) detection (HPLC-UVD) was developed for the extraction and determination of UV filters from water samples. The model analytes were 2,4-dihydroxybenzophenone (BP-1), benzophenone (BP) and 2-hydroxy-4-methoxybenzophenone (BP-3). The hydrophobic DES was prepared by mixing trioctylmethylammonium chloride (TAC) and decanoic acid (DecA). Various influencing factors (selection of the extractant, amount of DES, ultrasound duration, salt addition, sample volume, sample pH, centrifuge rate and duration) on UV filter recovery were systematically investigated. Under optimal conditions, the proposed method provided good recoveries in the range of 90.2-103.5% and relative standard deviations (inter-day and intra-day precision, n=5) below 5.9%. The enrichment factors for the analytes ranged from 67 to 76. The limits of detection varied from 0.15 to 0.30ngmL -1 , depending on the analytes. The linearities were between 0.5 and 500ngmL -1 for BP-1 and BP and between 1 and 500ngmL -1 for BP-3, with coefficients of determination greater than 0.99. Finally, the proposed method was applied to the determination of UV filters in swimming pool and river water samples, and acceptable relative recoveries ranging from 82.1 to 106.5% were obtained. Copyright © 2017. Published by Elsevier B.V.

  19. High Performance Liquid Chromatography-mass Spectrometry Analysis of High Antioxidant Australian Fruits with Antiproliferative Activity Against Cancer Cells.

    Science.gov (United States)

    Sirdaarta, Joseph; Maen, Anton; Rayan, Paran; Matthews, Ben; Cock, Ian Edwin

    2016-05-01

    145 unique mass signals were detected in the lemon aspen methanolic and aqueous extracts by nonbiased high-performance liquid chromatography-mass spectrometry analysis. Of these, 20 compounds were identified as being of particular interest due to their reported antioxidant and/or anticancer activities. The lack of toxicity and antiproliferative activity of the high antioxidant plant extracts against HeLa and CaCo2 cancer cell lines indicates their potential in the treatment and prevention of some cancers. Australian fruit extracts with high antioxidant contents were potent inhibitors of CaCo2 and HeLa carcinoma cell proliferationMethanolic lemon aspen extract was particularly potent, with IC50 values of 480 μg/mL (HeLa) and 769 μg/mL (CaCo2)High-performance liquid chromatography-mass spectrometry-quadrupole time-of-flight analysis highlighted and putatively identified 20 compounds in the antiproliferative lemon aspen extractsIn contrast, lower antioxidant content extracts stimulated carcinoma cell proliferationAll extracts with antiproliferative activity were nontoxic in the Artemia nauplii assay. Abbreviations used: DPPH: di (phenyl)- (2,4,6-trinitrophenyl) iminoazanium, HPLC: High-performance liquid chromatography, IC50: The concentration required to inhibit by 50%, LC50: The concentration required to achieve 50% mortality, MS: Mass spectrometry.

  20. High Performance Liquid Chromatography-mass Spectrometry Analysis of High Antioxidant Australian Fruits with Antiproliferative Activity Against Cancer Cells

    Science.gov (United States)

    Sirdaarta, Joseph; Maen, Anton; Rayan, Paran; Matthews, Ben; Cock, Ian Edwin

    2016-01-01

    g/mL). All other extracts were nontoxic. A total of 145 unique mass signals were detected in the lemon aspen methanolic and aqueous extracts by nonbiased high-performance liquid chromatography-mass spectrometry analysis. Of these, 20 compounds were identified as being of particular interest due to their reported antioxidant and/or anticancer activities. Conclusions: The lack of toxicity and antiproliferative activity of the high antioxidant plant extracts against HeLa and CaCo2 cancer cell lines indicates their potential in the treatment and prevention of some cancers. SUMMARY Australian fruit extracts with high antioxidant contents were potent inhibitors of CaCo2 and HeLa carcinoma cell proliferationMethanolic lemon aspen extract was particularly potent, with IC50 values of 480 μg/mL (HeLa) and 769 μg/mL (CaCo2)High-performance liquid chromatography-mass spectrometry-quadrupole time-of-flight analysis highlighted and putatively identified 20 compounds in the antiproliferative lemon aspen extractsIn contrast, lower antioxidant content extracts stimulated carcinoma cell proliferationAll extracts with antiproliferative activity were nontoxic in the Artemia nauplii assay. Abbreviations used: DPPH: di (phenyl)- (2,4,6-trinitrophenyl) iminoazanium, HPLC: High-performance liquid chromatography, IC50: The concentration required to inhibit by 50%, LC50: The concentration required to achieve 50% mortality, MS: Mass spectrometry. PMID:27279705

  1. Haemoglobin variants may cause significant differences in haemoglobin A1c as measured by high-performance liquid chromatography and enzymatic methods in diabetic patients: a cross-sectional study.

    Science.gov (United States)

    Otabe, Shuichi; Nakayama, Hitomi; Ohki, Tsuyoshi; Soejima, Eri; Tajiri, Yuji; Yamada, Kentaro

    2017-07-01

    Background We aimed to determine whether the discrepancy between haemoglobin A1c values determined by high-performance liquid chromatography and enzymatic haemoglobin A1c measurements in diabetic patients was clinically relevant. Methods We randomly recruited 1421 outpatients undergoing diabetic treatment and follow-up who underwent at least three haemoglobin A1c measurements between April 2014 and March 2015 at our clinic. In 6369 samples, haemoglobin A1c was simultaneously measured by HA-8160 and MetaboLead (enzymatic assay), and the values were compared. Results haemoglobin A1c measurements by high-performance liquid chromatography and enzymatic assay were strongly correlated (correlation coefficient: 0.9828, linear approximation curve y = 0.9986x - 0.2507). Mean haemoglobin A1c (6.8 ± 1.0%) measured by high-performance liquid chromatography was significantly higher than that measured by enzymatic assay (6.5 ± 1.0%, P liquid chromatography than those from enzymatic assay. Of these, three had Hb Toranomon [β112 (G14) Cys→Trp]. The fourth had Hb Ube-2 [α68 (E17) Asn→Asp]. One other subject presented consistently higher haemoglobin A1c values (>1%) by high-performance liquid chromatography than those from enzymatic assay and was diagnosed with a -77 (T > C) mutation in the δ-globin gene. These unrelated asymptomatic subjects had normal erythrocyte profiles, without anaemia. Conclusions We showed that haemoglobin A1c values measured by high-performance liquid chromatography were significantly higher than those measured by enzymatic assay in diabetic subjects. However, when an oversized deviation (>0.7%) between glycaemic control status and haemoglobin A1c is apparent, clinicians should check the methods used to measure haemoglobin A1c and consider the possible presence of a haemoglobin variant.

  2. Measurement of food flavonoids by high-performance liquid chromatography: A review.

    Science.gov (United States)

    Merken, H M; Beecher, G R

    2000-03-01

    The flavonoids are plant polyphenols found frequently in fruits, vegetables, and grains. Divided into several subclasses, they include the anthocyanidins, pigments chiefly responsible for the red and blue colors in fruits, fruit juices, wines, and flowers; the catechins, concentrated in tea; the flavanones and flavanone glycosides, found in citrus and honey; and the flavones, flavonols, and flavonol glycosides, found in tea, fruits, vegetables, and honey. Known for their hydrogen-donating antioxidant activity as well as their ability to complex divalent transition metal cations, flavonoids are propitious to human health. Computer-controlled high-performance liquid chromatography (HPLC) has become the analytical method of choice. Many systems have been developed for the detection and quantification of flavonoids across one, two, or three subclasses. A summary of the various HPLC and sample preparation methods that have been employed to quantify individual flavonoids within a subclass or across several subclasses are tabulated in this review.

  3. Clinical value of serum bilirubin subfractionation by high-performance liquid chromatography and conventional methods in patients with primary biliary cirrhosis

    NARCIS (Netherlands)

    Jansen, P. L.; Peters, W. H.; Janssens, A. R.

    1986-01-01

    The clinical value of serum bilirubin subfractionation, using high-performance liquid chromatography (HPLC), was studied in 26 patients with primary biliary cirrhosis (PBC) from whom 59 serum samples were obtained. Total bilirubin (TB) levels were determined by alkaline methanolysis and HPLC

  4. Improved method for the determination of serotonin in plasma by high-performance liquid chromatography using on-line sample pre-treatment

    NARCIS (Netherlands)

    Takkenberg, B.; Endert, E.; van Ingen, H. E.; Ackermans, M.

    1991-01-01

    An improved method for the determination of serotonin in platelet-rich plasma (PRP) and platelet-poor plasma (PPP), by reversed-phase high-performance liquid chromatography with electrochemical detection and direct plasma injection, is described. The chromatographic system comprises a strong

  5. Separation of deuteriated isotopomers of dopamine by ion-pair reversed-phase high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Masters, C.F.; Markey, S.P.; Mefford, I.N.; Duncan, M.W.

    1988-01-01

    The ion-pair reversed-phase separation of dopamine and deuterium-substituted dopamine isotopomers is described. Chromatographic parameters and deuterium isotope effects governing the resolution are examined and compared to the factors regulating the resolution are examined and compared to the factors regulating the resolution of the chemically distinct entities dopamine, norepinephrine, and epinephrine. The potential utility of the [ 2 H 7 ]dopamine, isotopomer as an internal standard for the high-performance liquid chromatography analysis of dopamine is demonstrated by using aluminum oxide extraction prior to chromatographic separation

  6. Plasma capric acid concentrations in healthy subjects determined by high-performance liquid chromatography.

    Science.gov (United States)

    Shrestha, Rojeet; Hui, Shu-Ping; Imai, Hiromitsu; Hashimoto, Satoru; Uemura, Naoto; Takeda, Seiji; Fuda, Hirotoshi; Suzuki, Akira; Yamaguchi, Satoshi; Hirano, Ken-Ichi; Chiba, Hitoshi

    2015-09-01

    Capric acid (FA10:0, decanoic acid) is a medium-chain fatty acid abundant in tropical oils such as coconut oil, whereas small amounts are present in milk of goat, cow, and human. Orally ingested FA10:0 is transported to the liver and quickly burnt within it. Only few reports are available for FA10:0 concentrations in human plasma. Fasting (n = 5, male/female = 3/2, age 31 ± 9.3 years old) and non-fasting (n = 106, male/female = 44/62, age 21.9 ± 3.2 years old) blood samples were collected from apparently healthy Japanese volunteers. The total FA10:0 in the plasma were measured by high-performance liquid chromatography after derivatization with 2-nitrophenylhydrazine followed by UV detection. Inter and intra-assay coefficient of variation of FA10:0 assay at three different concentrations ranged in 1.7-3.9 and 1.3-5.4%, respectively, with an analytical recovery of 95.2-104.0%. FA10:0 concentration was below detection limit (0.1 µmol/L) in each fasting human plasma. FA10:0 was not detected in 50 (47.2%) of 106 non-fasting blood samples, while 29 (27.4%) plasma samples contained FA10:0 less than or equal to 0.5 µmol/L (0.4 ± 0.1), and 27 (25.5%) contained it at more than 0.5 µmol/L (0.9 ± 0.3). A half of the non-fasting plasma samples contained detectable FA10:0. This simple, precise, and accurate high-performance liquid chromatography method might be useful for monitoring plasma FA10:0 during medium-chain triglycerides therapy. © The Author(s) 2015.

  7. Analytical Method Validation of High-Performance Liquid Chromatography and Stability-Indicating Study of Medroxyprogesterone Acetate Intravaginal Sponges

    Directory of Open Access Journals (Sweden)

    Nidal Batrawi

    2017-02-01

    Full Text Available Medroxyprogesterone acetate is widely used in veterinary medicine as intravaginal dosage for the synchronization of breeding cycle in ewes and goats. The main goal of this study was to develop reverse-phase high-performance liquid chromatography method for the quantification of medroxyprogesterone acetate in veterinary vaginal sponges. A single high-performance liquid chromatography/UV isocratic run was used for the analytical assay of the active ingredient medroxyprogesterone. The chromatographic system consisted of a reverse-phase C18 column as the stationary phase and a mixture of 60% acetonitrile and 40% potassium dihydrogen phosphate buffer as the mobile phase; the pH was adjusted to 5.6. The method was validated according to the International Council for Harmonisation (ICH guidelines. Forced degradation studies were also performed to evaluate the stability-indicating properties and specificity of the method. Medroxyprogesterone was eluted at 5.9 minutes. The linearity of the method was confirmed in the range of 0.0576 to 0.1134 mg/mL ( R 2 > 0.999. The limit of quantification was shown to be 3.9 µg/mL. Precision and accuracy ranges were found to be %RSD <0.2 and 98% to 102%, respectively. Medroxyprogesterone capacity factor value of 2.1, tailing factor value of 1.03, and resolution value of 3.9 were obtained in accordance with ICH guidelines. Based on the obtained results, a rapid, precise, accurate, sensitive, and cost-effective analysis procedure was proposed for quantitative determination of medroxyprogesterone in vaginal sponges. This analytical method is the only available method to analyse medroxyprogesterone in veterinary intravaginal dosage form.

  8. Fundamental and practical studies on high-performance liquid affinity chromatography of biopolymers with novel stationary phases

    Energy Technology Data Exchange (ETDEWEB)

    Bacolod, M.D.

    1992-01-01

    Rigid microparticulate stationary phases having surface-bound metal chelating functions were developed and evaluated in high performance metal chelate affinity chromatography of proteins. Silica- and polystyrene-divinylbenzene-based metal chelate sorbents were produced in wide pore and in non-porous type of column packings. A major effort has been placed on development of non-porous highly crosslinked polystyrene-divinylbenzene (PSDVB). These PSDVB microparticles were produced by a two-step swelling polymerization, and exhibited excellent mechanical strength over a wide range of flow-rates and composition used in high performance liquid chromatography (HPLC). Simple and reproducible hydrophilic coatings were developed for the surface modification of hydrophobic PSDVB supports. A tetradentate metal chelating ligand, ethylenediamine-N, N[prime]-diacetic acid (EDDA), was covalently bound to the surface of the various supports. Sorbents having iminodiacetic acid (IDA) metal chelating functions were also evaluated. The hydrophilic character and surface coverage of various stationary phases were assessed chromatographically. Studies concerning the effects of eluent pH as well as the nature and concentration of salts on retention and selectivity with different metal chelate stationary phases having various immobilized metal ions were carried out. Elution schemes were developed for rapid separation of proteins in metal chelate affinity chromatography. EDDA stationary phases in metal forms can be viewed as complementary to IDA stationary phases since they afforded different selectivity and retentivity toward proteins. Hydrophilic PSDVB could be functionalized with IDA or EDDA metal chelating ligands or lectins. The non-porous metal chelate stationary phases afforded rapid separation of proteins by the development of multiple gradient systems, which permitted higher column peak capacity, enabling the separation of a greater number of proteins in a single chromatographic run.

  9. Identification of tyrosinase specific inhibitors from Xanthium strumarium fruit extract using ultrafiltration-high performance liquid chromatography.

    Science.gov (United States)

    Wang, Zhiqiang; Hwang, Seung Hwan; Huang, Bo; Lim, Soon Sung

    2015-10-01

    In this study, a strategy based on ultrafiltration-high performance liquid chromatography coupled with diode array detection (UF-HPLC-DAD) was proposed for screening tyrosinase specific inhibitors in Xanthii fructus. The false negatives were distinguished by optimizing the UF-HPLC-DAD parameters to reduce the background noise; the false positives were distinguished by introducing a blocked tyrosinase in the control group for comparison. To obtain the best blocker, the competitive experiments were performed using various known ligands. Using this strategy, three competitive inhibitors (protocatechuic acid; 3,5-di-O-caffeoylquinic acid; and 1,5-di-O-caffeoylquinic acid) and one mixed-type inhibitor (chlorogenic acid) were identified. These results were verified using tyrosinase inhibition assay, kinetic analysis, and structural simulation of the complex. Our experimental results suggest that the proposed strategy could be useful for high-throughput identification of tyrosinase specific inhibitors in natural products. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Optimization of dispersive liquid-phase microextraction based on solidified floating organic drop combined with high-performance liquid chromatography for the analysis of glucocorticoid residues in food.

    Science.gov (United States)

    Huang, Yuan; Zheng, Zhiqun; Huang, Liying; Yao, Hong; Wu, Xiao Shan; Li, Shaoguang; Lin, Dandan

    2017-05-10

    A rapid, simple, cost-effective dispersive liquid-phase microextraction based on solidified floating organic drop (SFOD-LPME) was developed in this study. Along with high-performance liquid chromatography, we used the developed approach to determine and enrich trace amounts of four glucocorticoids, namely, prednisone, betamethasone, dexamethasone, and cortisone acetate, in animal-derived food. We also investigated and optimized several important parameters that influenced the extraction efficiency of SFOD-LPME. These parameters include the extractant species, volumes of extraction and dispersant solvents, sodium chloride addition, sample pH, extraction time and temperature, and stirring rate. Under optimum experimental conditions, the calibration graph exhibited linearity over the range of 1.2-200.0ng/ml for the four analytes, with a reasonable linearity(r 2 : 0.9990-0.9999). The enrichment factor was 142-276, and the detection limits was 0.39-0.46ng/ml (0.078-0.23μg/kg). This method was successfully applied to analyze actual food samples, and good spiked recoveries of over 81.5%-114.3% were obtained. Copyright © 2017. Published by Elsevier B.V.

  11. 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.

  12. Identification of glycosaminoglycans using high-performance liquid chromatography on a hydroxyapatite column.

    Science.gov (United States)

    Narita, H; Takeda, Y; Takagaki, K; Nakamura, T; Harata, S; Endo, M

    1995-11-20

    Glycosaminoglycans (heparin, heparan sulfate, dermatan sulfate, chondroitin sulfate, and hyaluronic acid) were labeled with a fluorescent reagent, 2-aminopyridine. The fluoro-labeled glycosaminoglycans were subjected to high-performance liquid chromatography on a hydroxyapatite column. The binding property of each glycosaminoglycan to hydroxyapatite was different. The structural properties of glycosaminoglycans bound to hydroxyapatite were then investigated using chemical desulfated or enzymic depolymerized glycosaminoglycans. This revealed that the sulfate content and molecular weight of the glycosaminoglycans correlated with their binding properties to hydroxyapatite. Desulfated dermatan sulfate but not desulfated chondroitin 6-sulfate bound to the hydroxyapatite. These data indicate that iduronic acid residues of glycosaminoglycans are important for the binding property. The method described which uses hydroxyapatite columns facilitates rapid separation and microanalysis of the glycosaminoglycans, especially dermatan sulfate and chondroitin sulfate.

  13. SIMULTANEOUS DETERMINATION OF PARACETAMOL AND IBUPROFENE MIXTURES BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

    Directory of Open Access Journals (Sweden)

    Sophi Damayanti

    2010-06-01

    Full Text Available Analytical method for the determination of paracetamol and ibuprofene mixtures has been developed by High Performance Liquid Chromatography using C-18 column and acetinitrile - phosphate buffer pH = 4.5 (75:25 containing 0.075% sodium hexanesulfunate as a mobile phase. The detector was set at 215 nm. Using such conditions, retention time for paracetamol and ibuprofen was 4.89 and 7.11 min, respectively. The recovery for paracetamol and ibuprofen was found to be 101.07± 0.73% and 102.02 ± 1.58%, respectively. The detector limits of the method was 1.30 and 1.60 μg/mL with the relative standard deviation (RSD 0.74 and 1.52% for paracetamol and ibuprofen, respectively.   Keywords: paracetamol, ibuprofen, multi-component, validation, HPLC.

  14. Development of high performance liquid chromatography method for miconazole analysis in powder sample

    Science.gov (United States)

    Hermawan, D.; Suwandri; Sulaeman, U.; Istiqomah, A.; Aboul-Enein, H. Y.

    2017-02-01

    A simple high performance liquid chromatography (HPLC) method has been developed in this study for the analysis of miconazole, an antifungal drug, in powder sample. The optimized HPLC system using C8 column was achieved using mobile phase composition containing methanol:water (85:15, v/v), a flow rate of 0.8 mL/min, and UV detection at 220 nm. The calibration graph was linear in the range from 10 to 50 mg/L with r 2 of 0.9983. The limit of detection (LOD) and limit of quantitation (LOQ) obtained were 2.24 mg/L and 7.47 mg/L, respectively. The present HPLC method is applicable for the determination of miconazole in the powder sample with a recovery of 101.28 % (RSD = 0.96%, n = 3). The developed HPLC method provides short analysis time, high reproducibility and high sensitivity.

  15. Discrimination of Black Ball-point Pen Inks by High Performance Liquid Chromatography (HPLC)

    International Nuclear Information System (INIS)

    Mohamed Izzharif Abdul Halim; Norashikin Saim; Rozita Osman; Halila Jasmani; Nurul Nadhirah Zainal Abidin

    2013-01-01

    In this study, thirteen types of black ball-point pen inks of three major brands were analyzed using high performance liquid chromatography (HPLC). Separation of the ink components was achieved using Bondapak C-18 column with gradient elution using water, ethanol and ethyl acetate. The chromatographic data obtained at wavelength 254.8 nm was analyzed using agglomerative hierarchical clustering (AHC) and principle component analysis (PCA). AHC was able to group the inks into three clusters. This result was supported by PCA, whereby distinct separation of the three different brands was achieved. Therefore, HPLC in combination with chemometric methods may be a valuable tool for the analysis of black ball-point pen inks for forensic purposes. (author)

  16. Introduction to modern liquid chromatography

    National Research Council Canada - National Science Library

    Snyder, Lloyd R; Kirkland, J. J; Dolan, John W

    2010-01-01

    "High-performance liquid chromatography (HPLC) is today the leading technique for chemical analysis and related applications, with an ability to separate, analyze, and/or purify virtually any sample...

  17. Comparison of high-performance liquid chromatography and supercritical fluid chromatography using evaporative light scattering detection for the determination of plasticizers in medical devices.

    Science.gov (United States)

    Lecoeur, Marie; Decaudin, Bertrand; Guillotin, Yoann; Sautou, Valérie; Vaccher, Claude

    2015-10-23

    Recently, interest in supercritical fluid chromatography (SFC) has increased due to its high throughput and the development of new system improving chromatographic performances. However, most papers dealt with fundamental studies and chiral applications and only few works described validation process of SFC method. Likewise, evaporative light scattering detection (ELSD) has been widely employed in liquid chromatography but only a few recent works presented its quantitative performances hyphenated with SFC apparatus. The present paper discusses about the quantitative performances of SFC-ELSD compared to HPLC-ELSD, for the determination of plasticizers (ATBC, DEHA, DEHT and TOTM) in PVC tubing used as medical devices. After the development of HPLC-ELSD, both methods were evaluated based on the total error approach using accuracy profile. The results show that HPLC-ELSD was more precise than SFC-ELSD but lower limits of quantitation were obtained by SFC. Hence, HPLC was validated in the ± 10% acceptance limits whereas SFC lacks of accuracy to quantify plasticizers. Finally, both methods were used to determine the composition of plasticized-PVC medical devices. Results demonstrated that SFC and HPLC both hyphenated with ELSD provided similar results. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Early detection of degraded A14-125I-insulin in human fibroblasts by the use of high performance liquid chromatography

    International Nuclear Information System (INIS)

    Stentz, F.B.; Harris, H.L.; Kitabchi, A.E.

    1983-01-01

    We studied the metabolism of A14-125I-insulin in intact human fibroblasts using high performance liquid chromatography (HPLC) to detect and separate its early degradation products. The high resolving power of HPLC enabled us to separate what has been considered ''intact insulin'' by Sephadex G-50 chromatography or TCA precipitability into two additional peaks that had decreased biochemical properties with respect to immunoprecipitability and receptor binding but not decreased TCA precipitability. We conclude that human fibroblast is capable of metabolizing insulin within 2 min at 37 degrees C into intermediate molecules that can be detected by HPLC but not by TCA precipitability or molecular sieve chromatography

  19. Resolution of RNA using high-performance liquid chromatography

    NARCIS (Netherlands)

    Mclaughlin, L.W.; Bischoff, Rainer

    1987-01-01

    High-performance liquid chromatographic techniques can be very effective for the resolution and isolation of nucleic acids. The characteristic ionic (phosphodiesters) and hydrophobic (nucleobases) properties of RNAs can be exploited for their separation. In this respect anion-exchange and

  20. A reversed-phase high-performance liquid chromatography method for the determination of cotrimoxazole (trimethoprim/ sulphamethoxazole) in children treated for malaria

    DEFF Research Database (Denmark)

    Rønn, A M; Mutabingwa, T K; Kreisby, S

    1999-01-01

    A high-performance liquid chromatography (HPLC) method was developed for the simultaneous analysis of trimethoprim (TMP), sulphamethoxazole (SMX), and acetylsulphamethoxazole (AcSMX) in small amounts of blood. The method involved precipitation with 50 microL trichloracetic acid (1M) to 125 micro...

  1. Salting-out homogenous extraction followed by ionic liquid/ionic liquid liquid-liquid micro-extraction for determination of sulfonamides in blood by high performance liquid chromatography.

    Science.gov (United States)

    Liu, Zhongling; Yu, Wei; Zhang, Hanqi; Gu, Fanbin; Jin, Xiangqun

    2016-12-01

    Salting-out homogenous extraction followed by ionic liquid/ionic liquid dispersive liquid-liquid micro-extraction system was developed and applied to the extraction of sulfonamides in blood. High-performance liquid chromatography was applied to the determination of the analytes. The blood sample was centrifuged to obtain the serum. After the proteins in the serum were removed in the presence of acetonitrile, ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate, dipotassium hydrogen phosphate, ionic liquid 1-Hexyl-3-methylimidazolium hexafluorophosphate were added into the resulting solution. After the resulting mixture was ultrasonically shaken and centrifuged, the precipitate was separated. The acetonitrile was added in the precipitate and the analytes were extracted into the acetonitrile phase. The parameters affecting the extraction efficiency, such as volume of ionic liquid, amount of dipotassium hydrogen phosphate, volume of dispersant, extraction time and temperature were investigated. The limits of detection of sulfamethizole (STZ), sulfachlorpyridazine (SCP), sulfamethoxazole (SMX) and Sulfisoxazole (SSZ) were 4.78, 3.99, 5.21 and 3.77μgL -1 , respectively. When the present method was applied to the analysis of real blood samples, the recoveries of analytes ranged from 90.0% to 113.0% and relative standard deviations were lower than 7.2%. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Quality control of 99mTc-DTPA-octreotide by reverse high performance liquid chromatography

    International Nuclear Information System (INIS)

    Cheng, Z.; Lin, Q.F.; Jin, X.H.; Wang, F.; Bai, H.S.; Chen, D.M.; Fan, H.Q.; Du, J.

    1998-01-01

    DTPA-Octreotide(Pentetreotide), a somatostatin analogue which can bind specifically and with high affinity to somatostatin receptor in vitro and vivo, labeled with 99m Tc by tin reduction in acetate buffer, has been characterized by Reverse-phase High performance Liquid Chromatography. The effect of different solvents, mobile phase pH, linear gradient and the injected volume on the separation efficiency was evaluated. The results show that the separation efficiency is best using μBondapak-C 18 (300x3.9 mm 2 ), linear gradient of 40% to 80% methanol (1.0 ml/min) in 0.05M acetate buffer (pH 5.5) over a 30 min period and maintaining for another 10 min. The labeled product is a mixture which mainly consists of five components (a, b, c, d, e) successfully proved by HPLC. Paper chromatography is also evaluated in this paper. It may be used to determine the radiochemical purity of the labeling product, but is not a good choice for the verification each components. (author)

  3. Ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction for the separation and determination of estrogens in water samples by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Zhang, Rui; Wang, Chuanliu; Yue, Qiaohong; Zhou, Tiecheng; Li, Na; Zhang, Hanqi; Hao, Xiaoke

    2014-11-01

    An ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction method was proposed for the extraction and concentration of 17-α-estradiol, 17-β-estradiol-benzoate, and quinestrol in environmental water samples by high-performance liquid chromatography with fluorescence detection. 1-Hexyl-3-methylimidazolium tetrafluoroborate was applied as foaming agent in the foam flotation process and dispersive solvent in microextraction. The introduction of the ion-pairing and salting-out agent NH4 PF6 was beneficial to the improvement of recoveries for the hydrophobic ionic liquid phase and analytes. Parameters of the proposed method including concentration of 1-hexyl-3-methylimidazolium tetrafluoroborate, flow rate of carrier gas, floatation time, types and concentration of ionic liquids, salt concentration in samples, extraction time, and centrifugation time were evaluated. The recoveries were between 98 and 105% with relative standard deviations lower than 7% for lake water and well water samples. The isolation of the target compounds from the water was found to be efficient, and the enrichment factors ranged from 4445 to 4632. This developing method is free of volatile organic solvents compared with regular extraction. Based on the unique properties of ionic liquids, the application of foam floatation, and dispersive liquid-liquid microextraction was widened. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. ANALISIS RESIDU KLORPIRIFOS DALAM SAYUR-SAYURAN DENGAN TEKNIK HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC

    Directory of Open Access Journals (Sweden)

    Aman Sentosa Panggabean

    2016-06-01

    Full Text Available The research about analysis of chlorpyrifos residue in vegetables by using High Performance Liquid Chromatography (HPLC technique has been done. To obtain the optimal measurement results, the measurement performed several important parameters in the chromatographic system was composition of mobile phase, volume injection sample, flow rate and pH eluent. Optimum measurement conditions obtained was mobile phase composition (water : methanol with 70 : 30, volume injection sample are 5 mL, flow rate are 0.5mL/menit and pH eluent are 7. The analytical performance that obtained is good showed with the reproducibility value as percentage coefficient variance (% CV was 0.0664%, limit of detection (LOD was 0.44 ppm, with a recovery percentage of > 95%. The results obtained showed the HPLC technique can be used for the routine analysis in the determination of chlorpyrifos for the vegetable samples. Keywords: Chlorpyrifos, Vegetables, HPLC.

  5. Evaluation and application of microwave-assisted extraction and dispersive liquid-liquid microextraction followed by high-performance liquid chromatography for the determination of polar heterocyclic aromatic amines in hamburger patties.

    Science.gov (United States)

    Aeenehvand, Saeed; Toudehrousta, Zahra; Kamankesh, Marzieh; Mashayekh, Morteza; Tavakoli, Hamid Reza; Mohammadi, Abdorreza

    2016-01-01

    This study developed an analytical method based on microwave-assisted extraction and dispersive liquid-liquid microextraction followed by high-performance liquid chromatography for the determination of three polar heterocyclic aromatic amines from hamburger patties. Effective parameters controlling the performance of the microextraction process, such as the type and volume of extraction and disperser solvents, microwave time, nature of alkaline aqueous solution, pH and salt amount, were optimized. The calibration graphs were linear in the range of 1-200 ng g(-1), with a coefficient of determination (R(2)) better than 0.9993. The relative standard deviations (RSD) for seven analyses were between 3.2% and 6.5%. The recoveries of those compounds in hamburger patties were from 90% to 105%. Detection limits were between 0.06 and 0.21 ng g(-1). A comparison of the proposed method with the existing literature demonstrates that it is a simple, rapid, highly selective and sensitive, and it gives good enrichment factors and detection limits for determining HAAs in real hamburger patties samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Screening antiallergic components from Carthamus tinctorius using rat basophilic leukemia 2H3 cell membrane chromatography combined with high-performance liquid chromatography and tandem mass spectrometry.

    Science.gov (United States)

    Han, Shengli; Huang, Jing; Cui, Ronghua; Zhang, Tao

    2015-02-01

    Carthamus tinctorius, used in traditional Chinese medicine, has many pharmacological effects, such as anticoagulant effects, antioxidant effects, antiaging effects, regulation of gene expression, and antitumor effects. However, there is no report on the antiallergic effects of the components in C. tinctorius. In the present study, we investigated the antiallergic components of C. tinctorius and its mechanism of action. A rat basophilic leukemia 2H3/cell membrane chromatography coupled online with high-performance liquid chromatography and tandem mass spectrometry method was developed to screen antiallergic components from C. tinctorius. The screening results showed that Hydroxysafflor yellow A, from C. tinctorius, was the targeted component that retained on the rat basophilic leukemia 2H3/cell membrane chromatography column. We measured the amount of β-hexosaminidase and histamine released in mast cells and the key markers of degranulation. The release assays showed that Hydroxysafflor yellow A could attenuate the immunoglobulin E induced release of allergic cytokines without affecting cell viability from 1.0 to 50.0 μM. In conclusion, the established rat basophilic leukemia 2H3 cell membrane chromatography coupled with online high-performance liquid chromatography and tandem mass spectrometry method successfully screened and identified Hydroxysafflor yellow A from C. tinctorius as a potential antiallergic component. Pharmacological analysis elucidated that Hydroxysafflor yellow A is an effective natural component for inhibiting immunoglobulin E-antigen-mediated degranulation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. EPA Method 8321B (SW-846): Solvent-Extractable Nonvolatile Compounds by High Performance Liquid Chromatography-Thermospray-Mass Spectrometry (HPLC-TS-MS) or Ultraviolet (UV) Detection

    Science.gov (United States)

    Method 8321B describes procedures for preparation and analysis of solid, aqueous liquid, drinking water and wipe samples using high performance liquid chromatography and mass spectrometry for extractable non-volatile compounds.

  8. Analysis of drugs of abuse in human plasma by dispersive liquid-liquid microextraction and high-performance liquid chromatography.

    Science.gov (United States)

    Fernández, P; Regenjo, M; Bermejo, A M; Fernández, A M; Lorenzo, R A; Carro, A M

    2015-04-01

    Opioids and cocaine are widely used at present, both for recreational purposes and as drugs of abuse. This raises the need to develop new analytical methods specifically designed for the simultaneous detection of several drugs of abuse in biological samples. In this work, dispersive liquid-liquid microextraction (DLLME) was assessed as a new sample treatment for the simultaneous extraction of morphine (MOR), 6-acetylmorphine (6AM), cocaine (COC), benzoylecgonine (BZE) and methadone (MET) from human plasma. Preliminary assays were done before developing an experimental design based on a Uniform Network Doehlert which allowed the optimum extraction conditions to be identified, namely: a volume of extractant solvent (chloroform) and dispersant solvent (acetonitrile) of 220 µl and 3.2 ml, respectively; 0.2 g of NaCl as a salting-out additive; pH 10.6 and ultrasound stirring for 3.5 min. The resulting extracts were analyzed by high-performance liquid chromatography with photodiode array detection (HPLC-PDA), using an XBridge® RP18 column (250 × 4.6 mm i.d., 5 µm particle size). Calibration graphs were linear over the concentration range 0.1-10 µg ml⁻¹, and detection limits ranged from 13.9 to 28.5 ng ml⁻¹. Precision calculated at three different concentration levels in plasma was included in the range 0.1-6.8% RSD. Recoveries of the five drugs were all higher than 84% on average. Finally the proposed method was successfully applied to 22 plasma samples from heroin, cocaine and/or methadone users, and the most frequently detected drug was benzoylecgonine, followed by methadone, cocaine and morphine. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Determination of Flurbiprofen in Human Plasma by High-Performance Liquid Chromatography.

    Science.gov (United States)

    Yilmaz, Bilal; Erdem, Ali Fuat

    2015-10-01

    A simple high-performance liquid chromatography method has been developed for determination of flurbiprofen in human plasma. The method was validated on an Ace C18 column using UV detection. The mobile phase was acetonitrile-0.05 M potassium dihydrogen phosphate solution (60:40, v/v) adjusted to pH 3.5 with phosphoric acid. The calibration curve was linear between the concentration range of 0.10-5.0 μg/mL. Intra- and inter-day precision values for flurbiprofen in plasma were flurbiprofen from human plasma were between 93.0 and 98.9%. The limits of detection and quantification of flurbiprofen were 0.03 and 0.10 μg/mL, respectively. In addition, this assay was applied to determine the pharmacokinetic parameters of flurbiprofen in six healthy Turkish volunteers who had been given 100 mg flurbiprofen. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Dispersive liquid-liquid microextraction followed by high-performance liquid chromatography-ultraviolet detection to determination of opium alkaloids in human plasma.

    Science.gov (United States)

    Ahmadi-Jouibari, Toraj; Fattahi, Nazir; Shamsipur, Mojtaba; Pirsaheb, Meghdad

    2013-11-01

    A novel, simple, rapid and sensitive dispersive liquid-liquid microextraction method based on the solidification of floating organic drop (DLLME-SFO) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was used to determine opium alkaloids in human plasma. During the extraction procedure, plasma protein was precipitated by using a mixture of zinc sulfate solution and acetonitrile. Some effective parameters on extraction were studied and optimized. Under the optimum conditions (extraction solvent: 30.0 μl 1-undecanol; disperser solvent: 470 μl acetone; pH: 9; salt addition: 1%(w/v) NaCl and extraction time: 0.5 min), calibration curves are linear in the range of 1.5-1000 μgl(-1) and limit of detections (LODs) are in the range of 0.5-5 μgl(-1). The relative standard deviations (RSDs) for 100 μgl(-1) of morphine and codeine, 10.0 μgl(-1) of papaverine and 20.0 μgl(-1) of noscapine in diluted human plasma are in the range of 4.3-7.4% (n=5). Finally, the method was successfully applied in the determination of opium alkaloids in the actual human plasma samples. The relative recoveries of plasma samples spiked with alkaloids are 88-110.5%. The obtained results show that DLLME-SFO combined with HPLC-UV is a fast and simple method for the determination of opium alkaloids in human plasma. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Methacrylate-bonded covalent-organic framework monolithic columns for high performance liquid chromatography.

    Science.gov (United States)

    Liu, Li-Hua; Yang, Cheng-Xiong; Yan, Xiu-Ping

    2017-01-06

    Covalent-organic frameworks (COFs) are a newfangled class of intriguing microporous materials. Considering their unique properties, COFs should be promising as packing materials for high performance liquid chromatography (HPLC). However, the irregular shape and sub-micrometer size of COFs synthesized via the traditional methods render the main obstacles for the application of COFs in HPLC. Herein, we report the preparation of methacrylate-bonded COF monolithic columns for HPLC to overcome the above obstacles. The prepared COF bonded monolithic columns not only show good homogeneity and permeability, but also give high column efficiency, good resolution and precision for HPLC separation of small molecules including polycyclic aromatic hydrocarbons, phenols, anilines, nonsteroidal anti-inflammatory drugs and benzothiophenes. Compared with the bare polymer monolithic column, the COF bonded monolithic columns show enhanced hydrophobic, π-π and hydrogen bond interactions in reverse phase HPLC. The results reveal the great potential of COF bonded monoliths for HPLC and COFs in separation sciences. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. [Determination of glycyrrhizinic acid in biotransformation system by reversed-phase high performance liquid chromatography].

    Science.gov (United States)

    Li, Hui; Lu, Dingqiang; Liu, Weimin

    2004-05-01

    A method for determining glycyrrhizinic acid in the biotransformation system by reversed-phase high performance liquid chromatography (RP-HPLC) was developed. The HPLC conditions were as follows: Hypersil C18 column (4.6 mm i.d. x 250 mm, 5 microm) with a mixture of methanol-water-acetic acid (70:30:1, v/v) as the mobile phase; flow rate at 1.0 mL/min; and UV detection at 254 nm. The linear range of glycyrrhizinic acid was 0.2-20 microg. The recoveries were 98%-103% with relative standard deviations between 0.16% and 1.58% (n = 3). The method is simple, rapid and accurate for determining glycyrrhizinic acid.

  13. Home-made online hyphenation of pressurized liquid extraction, turbulent flow chromatography, and high performance liquid chromatography, Cistanche deserticola as a case study.

    Science.gov (United States)

    Song, Qingqing; Li, Jun; Liu, Xiao; Zhang, Yuan; Guo, Liping; Jiang, Yong; Song, Yuelin; Tu, Pengfei

    2016-03-18

    Incompatibility between the conventional pressurized liquid extraction (PLE) devices and high performance liquid chromatography (HPLC) extensively hinders direct and green chemical analysis of herbal materials. Herein, a facile PLE module was configured, and then it was online hyphenated with HPLC via a turbulent flow chromatography (TFC) column. Regarding PLE module, a long PEEK tube (0.13 × 1000 mm) was employed to generate desired pressure (approximately 13.0 MPa) when warm acidic water (70 °C) was delivered as extraction solvent at a high flow rate (2.5 mL/min), and a hollow guard column (3.0 × 4.0 mm) was implemented to hold crude materials. Effluent was collected from the outlet of PEEK tube, concentrated, and subjected onto HPLC coupled with hybrid ion trap-time of flight mass spectrometer to assess the extraction efficiency and also to profile the chemical composition of Cistanche deserticola (CD) that is honored as "Ginseng of the desert". Afterwards, a TFC column was introduced to accomplish online transmission of low molecule weight components from PLE module to HPLC coupled with diode array detection, and two electronic 6-port/2-channel valves were in charge of alternating the whole system between extraction (0-3.0 min) and elution (3.0-35.0 min) phases. Quantitative method was developed and validated for simultaneous determination of eight primary phenylethanoid glycosides in CD using online PLE-TFC-HPLC. All findings demonstrated that the home-made platform is advantageous at direct chemical analysis, as well as time-, solvent-, and material-savings, suggesting a robust tool for chemical fingerprinting of herbs. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Detection of Free Polyamines in Plants Subjected to Abiotic Stresses by High-Performance Liquid Chromatography (HPLC).

    Science.gov (United States)

    Gong, Xiaoqing; Liu, Ji-Hong

    2017-01-01

    High-performance liquid chromatography (HPLC) is a sensitive, rapid, and accurate technique to detect and characterize various metabolites from plants. The metabolites are extracted with different solvents and eluted with appropriate mobile phases in a designed HPLC program. Polyamines are known to accumulate under abiotic stress conditions in various plant species and thought to provide protection against oxidative stress by scavenging reactive oxygen species. Here, we describe a common method to detect the free polyamines in plant tissues both qualitatively and quantitatively.

  15. Determination of triazine herbicides in juice samples by microwave-assisted ionic liquid/ionic liquid dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography.

    Science.gov (United States)

    Su, Rui; Li, Dan; Wu, Lijie; Han, Jing; Lian, Wenhui; Wang, Keren; Yang, Hongmei

    2017-07-01

    A novel microextraction method, termed microwave-assisted ionic liquid/ionic liquid dispersive liquid-liquid microextraction, has been developed for the rapid enrichment and analysis of triazine herbicides in fruit juice samples by high-performance liquid chromatography. Instead of using hazardous organic solvents, two kinds of ionic liquids, a hydrophobic ionic liquid (1-hexyl-3-methylimidazolium hexafluorophosphate) and a hydrophilic ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate), were used as the extraction solvent and dispersion agent, respectively, in this method. The extraction procedure was induced by the formation of cloudy solution, which was composed of fine drops of 1-hexyl-3-methylimidazolium hexafluorophosphate dispersed entirely into sample solution with the help of 1-butyl-3-methylimidazolium tetrafluoroborate. In addition, an ion-pairing agent (NH 4 PF 6 ) was introduced to improve recoveries of the ionic liquid phase. Several experimental parameters that might affect the extraction efficiency were investigated. Under the optimum experimental conditions, the linearity for determining the analytes was in the range of 5.00-250.00 μg/L, with the correlation coefficients of 0.9982-0.9997. The practical application of this effective and green method is demonstrated by the successful analysis of triazine herbicides in four juice samples, with satisfactory recoveries (76.7-105.7%) and relative standard deviations (lower than 6.6%). In general, this method is fast, effective, and robust to determine triazine herbicides in juice samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. [Detection of the preservative chlorphenesin in cosmetics by high-performance liquid chromatography].

    Science.gov (United States)

    Ikarashi, Yoshiaki; Miyazawa, Norimasa; Shimamura, Kimio; Sato, Nobuo; Yoshizawa, Ken-ichi; Hayashi, Masahito; Takano, Katsuhiro; Miyamoto, Michiko; Kojima, Takashi; Sakaguchi, Hiroshi; Fujiio, Makiko

    2009-01-01

    A simple determination method for preservative chlorphenesin in cosmetics was developed. Cosmetic samples were dissolved in methanol. The sample solution was analyzed by high-performance liquid chromatography (HPLC) with ODS column, using water-methanol (55:45) or water-acetonitrile (3:1) adjusted to pH 2.5 with phosphoric acid as the mobile phase. Chlorphenesin was detected with ultraviolet light detection at 280 nm. A linear relation was obtained between the peak areas and the concentrations of chlorphenesin in the range of 1-500 microg/ml. The determination limit of chlorphenesin was 1-2 microg/ml. Recoveries of chlorphenesin spiked in lotion and milky lotion at the levels of 0.03% and 0.3% were 98.8-100.0%. This method was applied for cosmetics including 0.03% and 0.3% of chlorphenesin and their content corresponded with the determined values.

  17. [Analysis of the preservative chlorphenesin in cosmetics by high performance liquid chromatography].

    Science.gov (United States)

    Zhu, Huijuan; Zhang, Weiqiang; Yang, Yanwei; Zhu, Ying

    2014-01-01

    An analytical method was developed for the determination of the preservative of chlorphenesin in cosmetics by high performance liquid chromatography (HPLC). A C18 column (250 mm x 4.6 mm, 5 microm) and a photodiode array detector were used. The mobile phase was methanol-water (55:45, v/v) with a flow rate of 1.0 mL/min. The detection wavelength was set at 280 nm and the column temperature was 25 degrees C. The limit of detection was 3 ng. A good linear relationship was obtained between the peak area and the mass concentration of chlorphenesin in the range of 1 - 500 mg/L and the correlation coefficient was 1.000 0. The recoveries of chlorphenesin at different spiked levels were 99.0% - 103% with the relative standard deviations (RSD) chlorphenesin in cosmetics.

  18. Buffer-Free High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a simple, economical and reproducible high performance liquid chromatographic (HPLC) method for the determination of theophylline in pharmaceutical dosage forms. Method: Caffeine was used as the internal standard and reversed phase C-18 column was used to elute the drug and ...

  19. Tantala-based sol-gel coating for capillary microextraction on-line coupled to high-performance liquid chromatography.

    Science.gov (United States)

    Tran, MinhPhuong; Turner, Erica B; Segro, Scott S; Fang, Li; Seyyal, Emre; Malik, Abdul

    2017-11-03

    A sol-gel organic-inorganic hybrid sorbent, consisting of chemically integrated tantalum (V) ethoxide (TaEO) and polypropylene glycol methacrylate (PPGM), was developed for capillary microextraction (CME). The sol-gel sorbent was synthesized within a fused silica capillary through hydrolytic polycondensation of TaEO and chemical incorporation of PPGM into the evolving sol-gel tantala network. A part of the organic-inorganic hybrid sol-gel network evolving in the vicinity of the capillary walls had favorable conditions to get chemically bonded to the silanol groups on the capillary surface forming a surface-bonded coating. The newly developed sol-gel sorbent was employed to isolate and enrich a variety of analytes from aqueous samples for on-line analysis by high-performance liquid chromatography (HPLC) equipped with a UV detector. CME was performed on aqueous samples containing trace concentrations of analytes representing polycyclic aromatic hydrocarbons, ketones, alcohols, amines, nucleosides, and nucleotides. This sol-gel hybrid coating provided efficient extraction with CME-HPLC detection limits ranging from 4.41pM to 28.19 pM. Due to direct chemical bonding between the sol-gel sorbent coating and the fused silica capillary inner surface, this sol-gel sorbent exhibited enhanced solvent stability. The sol-gel tantala-based sorbent also exhibited excellent pH stability over a wide pH range (pH 0-pH 14). Furthermore, it displayed great performance reproducibility in CME-HPLC providing run-to-run HPLC peak area relative standard deviation (RSD) values between 0.23% and 3.83%. The capillary-to-capillary RSD (n=3), characterizing capillary preparation method reproducibility, ranged from 0.24% to 4.11%. The results show great performance consistency and application potential for the sol-gel tantala-PPGM sorbent in various fields including biomedical, pharmaceutical, and environmental areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Automatic identification approach for high-performance liquid chromatography-multiple reaction monitoring fatty acid global profiling.

    Science.gov (United States)

    Tie, Cai; Hu, Ting; Jia, Zhi-Xin; Zhang, Jin-Lan

    2015-08-18

    Fatty acids (FAs) are a group of lipid molecules that are essential to organisms. As potential biomarkers for different diseases, FAs have attracted increasing attention from both biological researchers and the pharmaceutical industry. A sensitive and accurate method for globally profiling and identifying FAs is required for biomarker discovery. The high selectivity and sensitivity of high-performance liquid chromatography-multiple reaction monitoring (HPLC-MRM) gives it great potential to fulfill the need to identify FAs from complicated matrices. This paper developed a new approach for global FA profiling and identification for HPLC-MRM FA data mining. Mathematical models for identifying FAs were simulated using the isotope-induced retention time (RT) shift (IRS) and peak area ratios between parallel isotope peaks for a series of FA standards. The FA structures were predicated using another model based on the RT and molecular weight. Fully automated FA identification software was coded using the Qt platform based on these mathematical models. Different samples were used to verify the software. A high identification efficiency (greater than 75%) was observed when 96 FA species were identified in plasma. This FAs identification strategy promises to accelerate FA research and applications.

  1. Determination of phenmedipham and desmedipham in a commercial herbicide by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Lončar Eva S.

    2004-01-01

    Full Text Available Betanal AM-11 is the herbicide that is using to control one-year old weeds with wide leafs in sugar beet fields. Active ingredients of the herbicide are phenmedipham and desmedipham. Commercial emulsifiable concentrate (EC contains 80 g/L ( 10% of each active compound. We applied high performance liquid chromatography (HPLC with diode array detector (DAD at 254 nm for the determination of phenmedipham and desmedipham in commercial samples of Betanal AM-11. This method involves reversed-phase separation of the components on C-18 bonded silica with methanol-water (51+49, v/v as the eluent. The procedure was highly selective and reproducible and can be successfully used in determining contents of phenmedipham and desmedipham on micro and macro levels.

  2. Bioanalytical Applications of Fluorescence Line-Narrowing and Non-Line-Narrowing Spectroscopy Interfaced with Capillary Electrophoresis and High-Performance Liquid Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Kenneth Paul [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    Capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) are widely used analytical separation techniques with many applications in chemical, biochemical, and biomedical sciences. Conventional analyte identification in these techniques is based on retention/migration times of standards; requiring a high degree of reproducibility, availability of reliable standards, and absence of coelution. From this, several new information-rich detection methods (also known as hyphenated techniques) are being explored that would be capable of providing unambiguous on-line identification of separating analytes in CE and HPLC. As further discussed, a number of such on-line detection methods have shown considerable success, including Raman, nuclear magnetic resonance (NMR), mass spectrometry (MS), and fluorescence line-narrowing spectroscopy (FLNS). In this thesis, the feasibility and potential of combining the highly sensitive and selective laser-based detection method of FLNS with analytical separation techniques are discussed and presented. A summary of previously demonstrated FLNS detection interfaced with chromatography and electrophoresis is given, and recent results from on-line FLNS detection in CE (CE-FLNS), and the new combination of HPLC-FLNS, are shown.

  3. On-line radiometry in high-performance liquid chromatography using a storage loop

    International Nuclear Information System (INIS)

    Nieuwkerk, H.J. van.

    1987-01-01

    Difficulty with radiometric chromatography is that large measured volumes are required for accurate detections, but large volumes cause band widening and thus poor separation capacity. The solution proposed here is based on the use of a capillary storage loop for temporary residence of the column eluate. To avoid back mixing, the liquid is interspaced with a second, immiscible, phase ('spacer') so as to form a sequence of small 10-50 μl separate segments. This train passes the on-line radiometric detector to obtain a first scan of the chromatogram, called the 'direct' measurement. It then reaches the storage loop. The usual on-line UV measurement is done in the same run. The eluate cum spacer is, at a later stage, pumped through the detector at a greatly reduced flow rate to obtain the 'reversed' or 'delayed' measurement. Beta-detection is based on liquid scintillation. Accordingly, the (organic) liquid scintillant is used as the 'spacer'. In most cases it is possible to extract the analyte from the aqueous eluate into the organic phase during transport to and storage in the loop. This ensures a high counting efficiency. If the analyte is non-extractable, the counting efficiency is considerably less but the number of counts collected is still sufficient for quantitative assay, due to the extended counting time. The report is divided into 5 chapters, each dealing with a radiometric HPCL separation making use of this method. 36 figs.; 124 refs.; 16 tables

  4. Analysis of microdialysate monoamines, including noradrenaline, dopamine and serotonin, using capillary ultra-high performance liquid chromatography and electrochemical detection.

    Science.gov (United States)

    Ferry, Barbara; Gifu, Elena-Patricia; Sandu, Ioana; Denoroy, Luc; Parrot, Sandrine

    2014-03-01

    Electrochemical methods are very often used to detect catecholamine and indolamine neurotransmitters separated by conventional reverse-phase high performance liquid chromatography (HPLC). The present paper presents the development of a chromatographic method to detect monoamines present in low-volume brain dialysis samples using a capillary column filled with sub-2μm particles. Several parameters (repeatability, linearity, accuracy, limit of detection) for this new ultrahigh performance liquid chromatography (UHPLC) method with electrochemical detection were examined after optimization of the analytical conditions. Noradrenaline, adrenaline, serotonin, dopamine and its metabolite 3-methoxytyramine were separated in 1μL of injected sample volume; they were detected above concentrations of 0.5-1nmol/L, with 2.1-9.5% accuracy and intra-assay repeatability equal to or less than 6%. The final method was applied to very low volume dialysates from rat brain containing monoamine traces. The study demonstrates that capillary UHPLC with electrochemical detection is suitable for monitoring dialysate monoamines collected at high sampling rate. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. High-performance liquid chromatography with fluorescence detection for the rapid analysis of pheophytins and pyropheophytins in virgin olive oil.

    Science.gov (United States)

    Li, Xueqi; Woodman, Michael; Wang, Selina C

    2015-08-01

    Pheophytins and pyropheophytin are degradation products of chlorophyll pigments, and their ratios can be used as a sensitive indicator of stress during the manufacturing and storage of olive oil. They increase over time depending on the storage condition and if the oil is exposed to heat treatments during the refining process. The traditional analysis method includes solvent- and time-consuming steps of solid-phase extraction followed by analysis by high-performance liquid chromatography with ultraviolet detection. We developed an improved dilute/fluorescence method where multi-step sample preparation was replaced by a simple isopropanol dilution before the high-performance liquid chromatography injection. A quaternary solvent gradient method was used to include a fourth strong solvent wash on a quaternary gradient pump, which avoided the need to premix any solvents and greatly reduced the oil residues on the column from previous analysis. This new method not only reduces analysis cost and time but shows reliability, repeatability, and improved sensitivity, especially important for low-level samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Development and validation of high-performance liquid chromatography and high-performance thin-layer chromatography methods for the quantification of khellin in Ammi visnaga seed

    Science.gov (United States)

    Kamal, Abid; Khan, Washim; Ahmad, Sayeed; Ahmad, F. J.; Saleem, Kishwar

    2015-01-01

    Objective: The present study was used to design simple, accurate and sensitive reversed phase-high-performance liquid chromatography RP-HPLC and high-performance thin-layer chromatography (HPTLC) methods for the development of quantification of khellin present in the seeds of Ammi visnaga. Materials and Methods: RP-HPLC analysis was performed on a C18 column with methanol: Water (75: 25, v/v) as a mobile phase. The HPTLC method involved densitometric evaluation of khellin after resolving it on silica gel plate using ethyl acetate: Toluene: Formic acid (5.5:4.0:0.5, v/v/v) as a mobile phase. Results: The developed HPLC and HPTLC methods were validated for precision (interday, intraday and intersystem), robustness and accuracy, limit of detection and limit of quantification. The relationship between the concentration of standard solutions and the peak response was linear in both HPLC and HPTLC methods with the concentration range of 10–80 μg/mL in HPLC and 25–1,000 ng/spot in HPTLC for khellin. The % relative standard deviation values for method precision was found to be 0.63–1.97%, 0.62–2.05% in HPLC and HPTLC for khellin respectively. Accuracy of the method was checked by recovery studies conducted at three different concentration levels and the average percentage recovery was found to be 100.53% in HPLC and 100.08% in HPTLC for khellin. Conclusions: The developed HPLC and HPTLC methods for the quantification of khellin were found simple, precise, specific, sensitive and accurate which can be used for routine analysis and quality control of A. visnaga and several formulations containing it as an ingredient. PMID:26681890

  7. High-performance liquid chromatography coupled with tandem mass spectrometry technology in the analysis of Chinese Medicine Formulas: A bibliometric analysis (1997-2015).

    Science.gov (United States)

    He, Xi-Ran; Li, Chun-Guang; Zhu, Xiao-Shu; Li, Yuan-Qing; Jarouche, Mariam; Bensoussan, Alan; Li, Ping-Ping

    2017-01-01

    There is a recognized challenge in analyzing traditional Chinese medicine formulas because of their complex chemical compositions. The application of modern analytical techniques such as high-performance liquid chromatography coupled with a tandem mass spectrometry has improved the characterization of various compounds from traditional Chinese medicine formulas significantly. This study aims to conduct a bibliometric analysis to recognize the overall trend of high-performance liquid chromatography coupled with tandem mass spectrometry approaches in the analysis of traditional Chinese medicine formulas, its significance and possible underlying interactions between individual herbs in these formulas. Electronic databases were searched systematically, and the identified studies were collected and analyzed using Microsoft Access 2010, Graph Pad 5.0 software and Ucinet software package. 338 publications between 1997 and 2015 were identified, and analyzed in terms of annual growth and accumulated publications, top journals, forms of traditional Chinese medicine preparations and highly studied formulas and single herbs, as well as social network analysis of single herbs. There is a significant increase trend in using high-performance liquid chromatography coupled with tandem mass spectrometry related techniques in analysis of commonly used forms of traditional Chinese medicine formulas in the last 3 years. Stringent quality control is of great significance for the modernization and globalization of traditional Chinese medicine, and this bibliometric analysis provided the first and comprehensive summary within this field. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. A highly selective dispersive liquid-liquid microextraction approach based on the unique fluorous affinity for the extraction and detection of per- and polyfluoroalkyl substances coupled with high performance liquid chromatography tandem-mass spectrometry.

    Science.gov (United States)

    Wang, Juan; Shi, Yali; Cai, Yaqi

    2018-04-06

    In the present study, a highly selective fluorous affinity-based dispersive liquid-liquid microextraction (DLLME) technique was developed for the extraction and analysis of per- and polyfluoroalkyl substances (PFASs) followed by high performance liquid chromatography tandem-mass spectrometry. Perfluoro-tert-butanol with multiple C-F bonds was chosen as the extraction solvent, which was injected into the aqueous samples with a dispersive solvent (acetonitrile) in a 120:800 (μL, v/v) mixture for PFASs enrichment. The fluorous affinity-based extraction mechanism was confirmed by the significantly higher extraction recoveries for PFASs containing multiple fluorine atoms than those for compounds with fewer or no fluorine atoms. The extraction recoveries of medium and long-chain PFASs (CF 2  > 5) exceeded 70%, except perfluoroheptanoic acid, while those of short-chain PFASs were lower than 50%, implying that the proposed DLLME may not be suitable for their extraction due to weak fluorous affinity. This highly fluoroselective DLLME technique can greatly decrease the matrix effect that occurs in mass spectrometry detection when applied to the analysis of urine samples. Under the optimum conditions, the relative recoveries of PFASs with CF 2  > 5 ranged from 80.6-121.4% for tap water, river water and urine samples spiked with concentrations of 10, 50 and 100 ng/L. The method limits of quantification for PFASs in water and urine samples were in the range of 0.6-8.7 ng/L. Furthermore, comparable concentrations of PFASs were obtained via DLLME and solid-phase extraction, confirming that the developed DLLME technique is a promising method for the extraction of PFASs in real samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Monitoring gradient profile on-line in micro- and nano-high performance liquid chromatography using conductivity detection.

    Science.gov (United States)

    Zhang, Min; Chen, Apeng; Lu, Joann J; Cao, Chengxi; Liu, Shaorong

    2016-08-19

    In micro- or nano-flow high performance liquid chromatography (HPLC), flow-splitters and gradient elutions are commonly used for reverse phase HPLC separations. When a flow splitter was used at a high split-ratio (e.g., 1000:1 or higher), the actual gradient may deviate away from the programmed gradient. Sometimes, mobile phase concentrations can deviate by as much as 5%. In this work, we noticed that the conductivity (σ) of a gradient decreased with the increasing organic-solvent fraction (φ). Based on the relationship between σ and φ, a method was developed for monitoring gradient profile on-line to record any deviations in these HPLC systems. The conductivity could be measured by a traditional conductivity detector or a capacitively coupled contactless conductivity detector (C(4)D). The method was applied for assessing the performance of an electroosmotic pump (EOP) based nano-HPLC. We also observed that σ value of the gradient changed with system pressure; a=0.0175ΔP (R(2)=0.964), where a is the percentage of the conductivity increase and ΔP is the system pressure in bar. This effect was also investigated. Copyright © 2016. Published by Elsevier B.V.

  10. Simultaneous Determination of Four Preservatives in Foodstuffs by High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji

    2016-04-01

    Full Text Available Background and objectives:  High concentration of preservatives in food may result in gastrointestinal disturbances whereby some patients suffering from asthma, rhinitis, or urticaria. The aim of this study is the introduction and optimization a new method for simultaneous determination of four preservatives (SB, PS, MP, PP in foodstuff by high performance liquid chromatography. Materials and methods: Important factors in extraction, separation and determination process were optimized using the one variable at a time method.  Figures of merit of the proposed method were evaluated. The amount of SB, PS, MP, PP in some food samples were determined using the proposed method. Result: The results showed that the obtained chromatogram of extract was free of significant interferences. The preservatives recoveries ranged from 88% to 110 %. Concentration of SB, PS, MP and PP in the 20studied samples ranges between N.D-639.9, N.D -214.5, N.D -579.8 and N.D -30.5 mg kg-1, respectively  Conclusion: The performance and reliability of proposed method as a simple, efficient and fast method for determination of SB, PS, MP, PP in the food samples was demonstrated.

  11. Rapid determination of triclosan in personal care products using new in-tube based ultrasound-assisted salt-induced liquid-liquid microextraction coupled with high performance liquid chromatography-ultraviolet detection.

    Science.gov (United States)

    Chen, Ming-Jen; Liu, Ya-Ting; Lin, Chiao-Wen; Ponnusamy, Vinoth Kumar; Jen, Jen-Fon

    2013-03-12

    This paper describes the development of a novel, simple and efficient in-tube based ultrasound-assisted salt-induced liquid-liquid microextraction (IT-USA-SI-LLME) technique for the rapid determination of triclosan (TCS) in personal care products by high performance liquid chromatography-ultraviolet (HPLC-UV) detection. IT-USA-SI-LLME method is based on the rapid phase separation of water-miscible organic solvent from the aqueous phase in the presence of high concentration of salt (salting-out phenomena) under ultrasonication. In the present work, an indigenously fabricated home-made glass extraction device (8-mL glass tube inbuilt with a self-scaled capillary tip) was utilized as the phase separation device for USA-SI-LLME. After the extraction, the upper extractant layer was narrowed into the self-scaled capillary tip by pushing the plunger plug; thus, the collection and measurement of the upper organic solvent layer was simple and convenient. The effects of various parameters on the extraction efficiency were thoroughly evaluated and optimized. Under optimal conditions, detection was linear in the concentration range of 0.4-100ngmL(-1) with correlation coefficient of 0.9968. The limit of detection was 0.09ngmL(-1) and the relative standard deviations ranged between 0.8 and 5.3% (n=5). The applicability of the developed method was demonstrated for the analysis of TCS in different commercial personal care products and the relative recoveries ranged from 90.4 to 98.5%. The present method was proven to be a simple, sensitive, less organic solvent consuming, inexpensive and rapid procedure for analysis of TCS in a variety of commercially available personal care products or cosmetic preparations. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Simultaneous determination of acidic 3,4-dihydroxyphenylalanine metabolites and 5-hydroxyindole-3-acetic acid in urine by high-performance liquid chromatography

    NARCIS (Netherlands)

    Stroomer, A. E.; Overmars, H.; Abeling, N. G.; van Gennip, A. H.

    1990-01-01

    We describe a simple and rapid quantitative method for the simultaneous determination of 3,4-dihydroxyphenylalanine acid metabolites and 5-hydroxyindole-3-acetic acid. After solvent extraction from acidified urine, the acids are analyzed by reversed-phase high-performance liquid chromatography. For

  13. Classification of cultivation locations of Panax quinquefolius L samples using high performance liquid chromatography-electrospray ionization mass spectrometry and chemometric analysis

    Science.gov (United States)

    Panax quinquefolius L (P. quinquefolius L) samples grown in the United States and China were analyzed with high performance liquid chromatography-mass spectrometry (HPLC—MS). Prior to classification, the two-way datasets were subjected to pretreatment including baseline correction and retention tim...

  14. Determination of alpha-Tocopherol (vitamin E) in irradiated garlic by high performance liquid chromatography (HPLC)

    International Nuclear Information System (INIS)

    Rios, Magda Dias Goncalves; Penteado, Marilene de Vuono Camargo

    2003-01-01

    The effects of 60 Co ionizing radiations in doses of 0, 75, 100, 150, 200 and 250Gy on garlic, upon the α-tocopherol concentration were studied. The α-tocopherol contents were established by high performance liquid chromatography (HPLC), after direct hexane extraction from the garlic samples. The α-tocopherol was determined through normal phase column, and mobile phase was composed by hexane: iso-propyl alcohol (99:01 v/v), with 2mL/min flow rate and fluorescence detector. It is statistically shown that an irradiation dose of up to 150 Gy does not affect the garlic α-tocopherol content. (author)

  15. A green ionic liquid-based vortex-forced MSPD method for the simultaneous determination of 5-HMF and iridoid glycosides from Fructus Corni by ultra-high performance liquid chromatography.

    Science.gov (United States)

    Du, Kunze; Li, Jin; Bai, Yun; An, Mingrui; Gao, Xiu-Mei; Chang, Yan-Xu

    2018-04-01

    A simple and green ionic liquid-based vortex-forced matrix solid phase dispersion (IL-VFMSPD) method was presented to simultaneously extract 5-hydroxymethyl furfurol (5-HMF) and iridoid glycosides in Fructus Corni by ultra-high performance liquid chromatography. Ionic liquid was used as a green elution reagent in vortex-forced MSPD process. A few parameters such as the type of ionic liquid, the type of sorbent, ratio of sample to sorbent, the concentration and volume of ionic liquid, grinding time and vortex time, were investigated in detail and an orthogonal design experiment was introduced to confirm the best conditions in this procedure. With the final optimized method, the recoveries of the target compounds in Fructus Corni were in the range of 95.2-103% (RSD<5.0%) and the method displayed a good linearity within the range of 0.8-200 μg mL -1 for morroniside, sweroside, loganin, cornuside and 1.2-300 μg mL -1 for 5-HMF. The limits of detection ranged from 0.02 to 0.08 μg mL -1 for all compounds. The results showed that the newly established method was efficiently applied to extract and determine iridoid glycosides and 5-HMF for quality control of Fructus Corni. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. High-performance liquid chromatography of quinoidal imminium compounds derived from triphenylmethanes

    Science.gov (United States)

    Abidi, S.L.

    1983-01-01

    A series of eleven p-aminotriphenylmethane dyes have been studied by high-performance liquid chromatography (HPLC). The combined use of HPLC and spectrophotometry permits specific detection of these compounds in the visible range around 600 nm. As the high affinity of the imminium cations for the active sites of the hydrocarbonaceous stationary phase has presented difficulties for reversed-phase HPLC with pure solvents, organic electrolytes were added to the mobile phase to facilitate the elution of the components with improved selectivity, sensitivity (minimum detection limit, 0.1 μg/ml), and peak symmetry. The effects of chromatographic variables on the component retentivity were investigated. Retention times of the dye analytes decreased with increasing concentration of the added ionic reagent and with decreasing number of the hydrophobic alkyl substituents on the nitrogen atom. The influence of pH on the retention parameters appears to parallel that observed previously for cationic quaternary ammonium compounds. Among the acidic reagents employed, naphthalenesulfonic acid yielded the most satisfactory results. The use of binary electrolyte systems invariably improved the chromatographic behavior of the imminium solutes analyzed. Results obtained with two different octadecylsilica columns have been compared.

  17. Facile and sensitive determination of N-nitrosamines in food samples by high-performance liquid chromatography via combining fluorescent labeling with dispersive liquid-liquid microextraction.

    Science.gov (United States)

    Lu, Shuaimin; Wu, Di; Li, Guoliang; Lv, Zhengxian; Gong, Peiwei; Xia, Lian; Sun, Zhiwei; Chen, Guang; Chen, Xuefeng; You, Jinmao; Wu, Yongning

    2017-11-01

    The intake of N-nitrosamines (NAs) from foodstuffs is considered to be an important influence factor for several cancers. But the rapid and sensitive screening of NAs remains a challenge in the field of food safety. Inspired by that, a sensitive and rapid method was demonstrated for determination of five NAs (Nitrosopyrrolidine, Nitrosodimethylamine, Nitrosodiethylamine, Nitrosodipropylamine and Nitrosodibutylamine) using dispersive liquid-liquid microextraction (DLLME) followed by high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The NAs were firstly denitrosated and labeled by 2-(11H-benzo[a]carbazol-11-yl) ethyl carbonochloridate (BCEC-Cl) and finally enriched by DLLME. Furthermore, the main DLLME conditions were optimized systematically. Under the optimal conditions, satisfactory limits of detection (LODs) were obtained with a range of 0.01-0.07ngg -1 , which were significantly lower than the reported methods. The developed method showed many merits including rapidity, simplicity, high sensitivity and excellent selectivity, which shows a broad prospect in food safety analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Quantitative Determination of Bioactive Constituents in Noni Juice by High-performance Liquid Chromatography with Electrospray Ionization Triple Quadrupole Mass Spectrometry.

    Science.gov (United States)

    Yan, Yongqiu; Lu, Yu; Jiang, Shiping; Jiang, Yu; Tong, Yingpeng; Zuo, Limin; Yang, Jun; Gong, Feng; Zhang, Ling; Wang, Ping

    2018-01-01

    Noni juice has been extensively used as folk medicine for the treatment of arthritis, infections, analgesic, colds, cancers, and diabetes by Polynesians for many years. Due to the lack of standard scientific evaluation methods, various kinds of commercial Noni juice with different quality and price were available on the market. To establish a sensitive, reliable, and accurate high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-MS/MS) method for separation, identification, and simultaneous quantitative analysis of bioactive constituents in Noni juice. The analytes and eight batches of commercially available samples from different origins were separated and analyzed by the HPLC-ESI-MS/MS method on an Agilent ZORBAX SB-C 18 (150 mm × 4.6 mm i.d., 5 μm) column using a gradient elution of acetonitrile-methanol-0.05% glacial acetic acid in water (v/v) at a constant flow rate of 0.5 mL/min. Seven components were identification and all of the assay parameters were within the required limits. Components were within the correlation coefficient values ( R 2 ≥ 0.9993) at the concentration ranges tested. The precision of the assay method was high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometryThe presented method was successfully applied to the quality control of eight batches of commercially available samples of Noni juiceThis method is simple, sensitive, reliable, accurate, and efficient method with strong specificity, good precision, and high recovery rate and provides a reliable basis for quality control of Noni juice. Abbreviations used: HPLC-ESI-MS/MS: High-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry, LOD: Limit of detection, LOQ: Limit of quantitation, S/N: Signal-to-noise ratio, RSD: Relative standard deviations, DP: Declustering potential, CE: Collision energy, MRM: Multiple reaction monitoring, RT

  19. Application and optimization of microwave-assisted extraction and dispersive liquid-liquid microextraction followed by high-performance liquid chromatography for sensitive determination of polyamines in turkey breast meat samples.

    Science.gov (United States)

    Bashiry, Moein; Mohammadi, Abdorreza; Hosseini, Hedayat; Kamankesh, Marzieh; Aeenehvand, Saeed; Mohammadi, Zaniar

    2016-01-01

    A novel method based on microwave-assisted extraction and dispersive liquid-liquid microextraction (MAE-DLLME) followed by high-performance liquid chromatography (HPLC) was developed for the determination of three polyamines from turkey breast meat samples. Response surface methodology (RSM) based on central composite design (CCD) was used to optimize the effective factors in DLLME process. The optimum microextraction efficiency was obtained under optimized conditions. The calibration graphs of the proposed method were linear in the range of 20-200 ng g(-1), with the coefficient determination (R(2)) higher than 0.9914. The relative standard deviations were 6.72-7.30% (n = 7). The limits of detection were in the range of 0.8-1.4 ng g(-1). The recoveries of these compounds in spiked turkey breast meat samples were from 95% to 105%. The increased sensitivity in using the MAE-DLLME-HPLC-UV has been demonstrated. Compared with previous methods, the proposed method is an accurate, rapid and reliable sample-pretreatment method. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Fiber-based monolithic columns for liquid chromatography.

    Science.gov (United States)

    Ladisch, Michael; Zhang, Leyu

    2016-10-01

    Fiber-based monoliths for use in liquid chromatographic separations are defined by columns packed with aligned fibers, woven matrices, or contiguous fiber structures capable of achieving rapid separations of proteins, macromolecules, and low molecular weight components. A common denominator and motivating driver for this approach, first initiated 25 years ago, was reducing the cost of bioseparations in a manner that also reduced residence time of retained components while achieving a high ratio of mass to momentum transfer. This type of medium, when packed into a liquid chromatography column, minimized the fraction of stagnant liquid and resulted in a constant plate height for non-adsorbing species. The uncoupling of dispersion from eluent flow rate enabled the surface chemistry of the stationary phase to be considered separately from fluid transport phenomena and pointed to new ways to apply chemistry for the engineering of rapid bioseparations. This paper addresses developments and current research on fiber-based monoliths and explains how the various forms of this type of chromatographic stationary phase have potential to provide new tools for analytical and preparative scale separations. The different stationary phases are discussed, and a model that captures the observed constant plate height as a function of mobile phase velocity is reviewed. Methods that enable hydrodynamically stable fiber columns to be packed and operated over a range of mobile phase flow rates, together with the development of new fiber chemistries, are shown to provide columns that extend the versatility of liquid chromatography using monoliths, particularly at the preparative scale. Graphical Abstract Schematic representation of a sample mixture being separated by a rolled-stationary phase column, resulting separated peaks shown in the chromatogram.

  1. Integration of electrochemistry with ultra-performance liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Cai, Yi; Zheng, Qiuling; Liu, Yong; Helmy, Roy; Loo, Joseph A; Chen, Hao

    2015-01-01

    This study presents the development of ultra-performance liquid chromatography (UPLC) mass spectrometry (MS) combined with electrochemistry (EC) for the first time and its application for the structural analysis of proteins/peptides that contain disulfide bonds. In our approach, a protein/peptide mixture sample undergoes a fast UPLC separation and subsequent electrochemical reduction in an electrochemical flow cell followed by online MS and tandem mass spectrometry (MS/MS) analyses. The electrochemical cell is coupled to the mass spectrometer using our recently developed desorption electrospray ionization (DESI) interface. Using this UPLC/EC/DESI-MS method, peptides that contain disulfide bonds can be differentiated from those without disulfide bonds, as the former are electroactive and reducible. MS/MS analysis of the disulfide-reduced peptide ions provides increased information on the sequence and disulfide-linkage pattern. In a reactive DESI- MS detection experiment in which a supercharging reagent was used to dope the DESI spray solvent, increased charging was obtained for the UPLC-separated proteins. Strikingly, upon online electrolytic reduction, supercharged proteins (e.g., α-lactalbumin) showed even higher charging, which will be useful in top- down protein structure MS analysis as increased charges are known to promote protein ion dissociation. Also, the separation speed and sensitivity are enhanced by approximately 1(~)2 orders of magnitude by using UPLC for the liquid chromatography (LC)/EC/MS platform, in comparison to the previously used high- performance liquid chromatography (HPLC). This UPLC/EC/DESI-MS method combines the power of fast UPLC separation, fast electrochemical conversion, and online MS structural analysis for a potentially valuable tool for proteomics research and bioanalysis.

  2. High-performance liquid chromatography of metal complexes of pheophytins a and b

    International Nuclear Information System (INIS)

    Brykina, G.D.; Lazareva, E.E.; Uvarova, M.I.; Shpigun, O.A.

    1997-01-01

    Cu(2), Zn(2), Pb(2), Hg(2), and Ce(4) complexes of phenophytins a and b were synthesized. The chromatographic retention parameters of pheophytins a and b, chlorophylls a and b, and the above complexes were determined under conditions of normal-phase and reversed-phase high-performance liquid chromatography (HPLC). The adsorption of metal pheophytinates in the hexane-n-butanol (96:4)-Silasorb 600 and acetonitrile-ethanol-acetic acid (40:40:16)-Nucleosil C 18 systems was studied by HPLC. Factors that affect the chromatographic and adsorption characteristics of compounds (structural differences between pheophytinates of the a and b series, the nature of the central metal atom, and the nature of the mobile and stationary phases) are discussed. It is demonstrated that pheophytins a and b their metal complexes can be identified and quantiatively determined by HPLC in the concentration range (0.6-44.0)[10 -6 M

  3. Optimisation of pressurized liquid extraction using a multivariate chemometric approach for the determination of anticancer drugs in sludge by ultra high performance liquid chromatography-tandem mass spectrometry

    OpenAIRE

    Seira , Jordan; Claparols , Catherine; Joannis-Cassan , Claire; Albasi , Claire; Montréjaud-Vignoles , Mireille; Sablayrolles , Caroline

    2013-01-01

    International audience; The present paper describes an analytical method for the determination of 2 widely administered anticancer drugs, ifosfamide and cyclophosphamide, contained in sewage sludge. The method relies on the extraction from the solid matrix by pressurized liquid extraction, sample purification by solid-phase extraction and analysis by ultra high performance liquid chromatography coupled with tandem mass spectrometry. The different parameters affecting the extraction efficiency...

  4. Development of On-Line High Performance Liquid Chromatography (HPLC)-Biochemical Detection Methods as Tools in the Identification of Bioactives

    Science.gov (United States)

    Malherbe, Christiaan J.; de Beer, Dalene; Joubert, Elizabeth

    2012-01-01

    Biochemical detection (BCD) methods are commonly used to screen plant extracts for specific biological activities in batch assays. Traditionally, bioactives in the most active extracts were identified through time-consuming bio-assay guided fractionation until single active compounds could be isolated. Not only are isolation procedures often tedious, but they could also lead to artifact formation. On-line coupling of BCD assays to high performance liquid chromatography (HPLC) is gaining ground as a high resolution screening technique to overcome problems associated with pre-isolation by measuring the effects of compounds post-column directly after separation. To date, several on-line HPLC-BCD assays, applied to whole plant extracts and mixtures, have been published. In this review the focus will fall on enzyme-based, receptor-based and antioxidant assays. PMID:22489144

  5. Two-way and three-way approaches to ultra high performance liquid chromatography-photodiode array dataset for the quantitative resolution of a two-component mixture containing ciprofloxacin and ornidazole.

    Science.gov (United States)

    Dinç, Erdal; Ertekin, Zehra Ceren; Büker, Eda

    2016-09-01

    Two-way and three-way calibration models were applied to ultra high performance liquid chromatography with photodiode array data with coeluted peaks in the same wavelength and time regions for the simultaneous quantitation of ciprofloxacin and ornidazole in tablets. The chromatographic data cube (tensor) was obtained by recording chromatographic spectra of the standard and sample solutions containing ciprofloxacin and ornidazole with sulfadiazine as an internal standard as a function of time and wavelength. Parallel factor analysis and trilinear partial least squares were used as three-way calibrations for the decomposition of the tensor, whereas three-way unfolded partial least squares was applied as a two-way calibration to the unfolded dataset obtained from the data array of ultra high performance liquid chromatography with photodiode array detection. The validity and ability of two-way and three-way analysis methods were tested by analyzing validation samples: synthetic mixture, interday and intraday samples, and standard addition samples. Results obtained from two-way and three-way calibrations were compared to those provided by traditional ultra high performance liquid chromatography. The proposed methods, parallel factor analysis, trilinear partial least squares, unfolded partial least squares, and traditional ultra high performance liquid chromatography were successfully applied to the quantitative estimation of the solid dosage form containing ciprofloxacin and ornidazole. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Qualitative and Quantitative Analysis of Volatile Components of Zhengtian Pills Using Gas Chromatography Mass Spectrometry and Ultra-High Performance Liquid Chromatography.

    Science.gov (United States)

    Liu, Cui-Ting; Zhang, Min; Yan, Ping; Liu, Hai-Chan; Liu, Xing-Yun; Zhan, Ruo-Ting

    2016-01-01

    Zhengtian pills (ZTPs) are traditional Chinese medicine (TCM) which have been commonly used to treat headaches. Volatile components of ZTPs extracted by ethyl acetate with an ultrasonic method were analyzed by gas chromatography mass spectrometry (GC-MS). Twenty-two components were identified, accounting for 78.884% of the total components of volatile oil. The three main volatile components including protocatechuic acid, ferulic acid, and ligustilide were simultaneously determined using ultra-high performance liquid chromatography coupled with diode array detection (UHPLC-DAD). Baseline separation was achieved on an XB-C18 column with linear gradient elution of methanol-0.2% acetic acid aqueous solution. The UHPLC-DAD method provided good linearity (R (2) ≥ 0.9992), precision (RSD components, protocatechuic acid, ferulic acid, and ligustilide, in 13 batches of ZTPs, which is suitable for discrimination and quality assessment of ZTPs.

  7. [Separation and identification of bovine lactoferricin by high performance liquid chromatography-matrix-assisted laser desorption/ionization time of flight/ time of flight mass spectrometry].

    Science.gov (United States)

    An, Meichen; Liu, Ning

    2010-02-01

    A high performance liquid chromatography-matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometry (HPLC-MALDI-TOF/TOF MS) method was developed for the separation and identification of bovine lactoferricin (LfcinB). Bovine lactoferrin was hydrolyzed by pepsin and then separated by ion exchange chromatography and reversed-phase liquid chromatography (RP-LC). The antibacterial activities of the fractions from RP-LC separation were determined and the protein concentration of the fraction with the highest activity was measured, whose sequence was indentified by MALDI-TOF/TOF MS. The relative molecular mass of LfcinB was 3 124.89 and the protein concentration was 18.20 microg/mL. The method of producing LfcinB proposed in this study has fast speed, high accuracy and high resolution.

  8. Automated high performance liquid chromatography and liquid scintillation counting determination of pesticide mixture octanol/water partition rates

    International Nuclear Information System (INIS)

    Moody, R.P.; Carroll, J.M.; Kresta, A.M.

    1987-01-01

    Two novel methods are reported for measuring octanol/water partition rates of pesticides. A liquid scintillation counting (LSC) method was developed for automated monitoring of 14 C-labeled pesticides partitioning in biphasic water/octanol cocktail systems with limited success. A high performance liquid chromatography (HPLC) method was developed for automated partition rate monitoring of several constituents in a pesticide mixture, simultaneously. The mean log Kow +/- SD determined from triplicate experimental runs were for: 2,4-D-DMA (2,4-dichlorophenoxyacetic acid dimethylamine), 0.65 +/- .17; Deet (N,N-diethyl-m-toluamide), 2.02 +/- .01; Guthion (O,O-dimethyl-S-(4-oxo-1,2,3-benzotriazin-3(4H)-ylmethyl) phosphorodithioate), 2.43 +/- .03; Methyl-Parathion (O,O-dimethyl-O-(p-nitrophenyl) phosphorothioate), 2.68 +/- .05; and Fenitrothion (O,O-dimethyl O-(4-nitro-m-tolyl) phosphorothioate), 3.16 +/- .03. A strong positive linear correlation (r = .9979) was obtained between log Kow and log k' (log Kow = 2.35 (log k') + 0.63). The advantages that this automated procedure has in comparison with the standard manual shake-flask procedure are discussed

  9. Rapid determination of some beta-blockers in complicated matrices by tandem dispersive liquid-liquid microextraction followed by high performance liquid chromatography.

    Science.gov (United States)

    Hemmati, Maryam; Asghari, Alireza; Bazregar, Mohammad; Rajabi, Maryam

    2016-11-01

    In this research work, an efficient tandem dispersive liquid-liquid microextraction (TDLLME) procedure coupled with high performance liquid chromatography-ultraviolet detection (HPLC-UV) was successfully applied for the determination of beta-blockers in human plasma and pharmaceutical wastewater samples. High clean-up and preconcentration factor are easily and rapidly feasible via this novel, cheap, and safe microextraction method, leading to high quality experimental data. It consists of two sequential dispersive liquid-liquid microextraction methods, accomplished via air/ultrasonic agitation and air agitation, respectively. In order to enrich the optimal values for the mentioned procedures, the Box-Behnken design (BBD) combined with the desirability function (DF) was used. The optimum values were found to be 11.0 % (w/v) of the salt amount, an initial pH value of 12.0, 103 μL of organic extractant phase, and 45 μL of aqueous extractant phase with pH value of 2.0, resulted in reasonable recovery percentages with a logical desirability. Under optimal experimental conditions, good linear ranges (3-2000 ng mL -1 for metoprolol and 2.5-2500 ng mL -1 for propranolol with the correlation of determinations (R 2 s) higher than 0.99) and low limits of detection (0.8 and 1.0 ng mL -1 for propranolol and metoprolol, respectively) were obtainable. Also, TDLLME-HPLC-UV provided good proper repeatabilities (relative standard deviations (RSDs) below 5.7 %, n = 3) and high enrichment factors (EFs) of 75-100. Graphical abstract TDLLME of beta-blockers from complicated matrices.

  10. Determination of Four Major Saponins in Skin and Endosperm of Seeds of Horse Chestnut (Aesculus Hippocastanum L.) Using High Performance Liquid Chromatography with Positive Confirmation by Thin Layer Chromatography

    OpenAIRE

    Abudayeh, Zead Helmi Mahmoud; Al Azzam, Khaldun Mohammad; Naddaf, Ahmad; Karpiuk, Uliana Vladimirovna; Kislichenko, Viktoria Sergeevna

    2015-01-01

    urpose: To separate and quantify four major saponins in the extracts of the skin and the endosperm of seeds of horse chestnut (Aesculus hippocastanum L.) using ultrasonic solvent extraction followed by a high performance liquid chromatography-diode array detector (HPLC-DAD) with positive confirmation by thin layer chromatography (TLC). Methods: The saponins: escin Ia, escin Ib, isoescin Ia and isoescin Ib were extracted using ultrasonic extraction method. The optimized ex...

  11. L-ascorbic acid losses in Kenyan vegetables during cooking as determined by high performance liquid chromatography

    OpenAIRE

    N.M.N. Wekesa; S.C. Chhabra; H.M. Thairu

    2001-01-01

    The loss of L-ascorbic acid (L-AA) in 14 different cooked local vegetables found in Nairobi markets was determined by high performance liquid chromatography. The effect of quantity of water on the loss of L-AA during cooking was studied with cowpea leaves. It was found that more L-AA was lost when larger amount of water was used than when smaller amount was used. The effect of the sharpness of the knife on the loss of L-AA was studied with spinach. It was found that more loss of L-AA occurred...

  12. Determination of 2-naphthylamine in urine by a novel reversed-phase high-performance liquid chromatography method

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Poulsen, O M; Christensen, J M

    1992-01-01

    A high-performance liquid chromatographic method for the determination of 2-naphthylamine in urine using fluorescence detection was developed. The method validation analysis showed the method to be in analytical control, i.e. the distribution of the difference between the observed and true values...... of the method evaluation samples did not deviate significantly from the normal distribution. The recovery of the method was 85%. The entire run time of chromatography was 10 min using isocratic elution (acetonitrile-water, 35:65), and the retention time for 2-naphthylamine was 5.8 min. The relative short time...

  13. [Determination of sulpride in human plasma by high performance liquid chromatography].

    Science.gov (United States)

    Yu, X; Luo, Z; Tang, J; Yu, P

    1997-11-01

    This paper describes a reliable method for the pharmacokinetic study of Sulpride in human plasma by reversed-phase high performance liquid chromatography. To compensate the loss of Sulpride during the extraction procedure we used an internal standard very similar in chemical structure and UV absorbance to those of Sulpride. The mobile phase was methanol-water-acetic acid (60:30:1) with a flow rate of 1.2 mL/min. A UV detector was used at 290 nm. The linear range was 5-100 mg/L and the detectable limit was 1.0 mg/L. The recovery and RSD were 97.95%-99.96% and 2.6%-5.1% respectively. The results showed that this method is a sensitive and accurate one which makes the pharmacokinetic study of Sulpride possible. If the concentration was too low to be detected by UV monitor, a fluorescence detector could be used with the excitation wavelength at 299 nm and emission at 342 nm. We analyzed the plasma samples from 30 day-treated psychotic patients and got the satisfactory results.

  14. The high pressure electronic control system in liquid chromatography

    International Nuclear Information System (INIS)

    Popescu, Stefan; Popeneciu, Gabriel; Toadere, Florin

    2002-01-01

    The Liquid Chromatography system can perform a wide variety of measurements and separations especially for the organic liquids, with maximum applications flexibility for less than half price of Gas Chromatography. The repeatability and accuracy of results in quantitative high pressure liquid chromatography are highly dependent on the reproducibility and accuracy of both integrated flow rate and mobile phase composition. Flow rate fluctuation leads to poor reproducibility in both integrated peak areas and retention times. Similarly, poor control of mobile phase composition will cause poor repeatability of retention time and peak heights. The our Solvent Delivery System SDS 200 is a single pump system which provides precise compensated flow rates from 0.01 to 10 mL/min, selectable upper pressure limits of 0 to 100 bar or 10 to 450 bar, and solvent compressibility correction. Ternary solvent system on-line mixing capability saves time, reduces solvent waste and provides more flexibility for difficult separations. The pump itself has two different displacement pistons which are used alternately on both suction and discharge, so that intake of the solvent are synchronous. The evacuated solvent from the two pump's chambers is mixed in the reference unit and then is supplied to the damping unit for flow ripple reduction. The SDS Electronic Module ensures the functions: controls the programmed flow rate, detects and shows the solvent pressure in solvent, supplies the step motor, measures and limits the solvent pressure. The control panel of SDS 200, contains a two-stages flow decimal programmer, a eight-positions knob for upper pressure limits, an alarm LED and a parallel port for connection to a PC system. (authors)

  15. Quantitative Analysis of Ingenol in Euphorbia species via Validated Isotope Dilution Ultra-high Performance Liquid Chromatography Tandem Mass Spectrometry

    Czech Academy of Sciences Publication Activity Database

    Béres, T.; Dragull, K.; Pospíšil, Jiří; Tarkowská, Danuše; Dančák, M.; Bíba, Ondřej; Tarkowski, P.; Doležal, K.; Strnad, Miroslav

    2018-01-01

    Roč. 29, č. 1 (2018), s. 23-29 ISSN 0958-0344 R&D Projects: GA ČR GA17-14007S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Euphorbia genus * ingenol * isotope-dilution method * mass spectrometry * ultra-high performance liquid chromatography Subject RIV: FD - Oncology ; Hematology OBOR OECD: Analytical chemistry Impact factor: 2.292, year: 2016

  16. Simultaneous and rapid determination of deoxynivalenol and its acetylate derivatives in wheat flour and rice by ultra high performance liquid chromatography with photo diode array detection.

    Science.gov (United States)

    Xu, Jiao-Jiao; Zhou, Jian; Huang, Bai-Fen; Cai, Zeng-Xuan; Xu, Xiao-Min; Ren, Yi-Ping

    2016-06-01

    A simple and reliable method of ultra high performance liquid chromatography coupled with photo-diode array detection has been proposed for the simultaneous determination of deoxynivalenol and its acetylated derivatives in wheat flour and rice, especially focusing on the optimization of sample extraction, cleanup, and chromatographic separation conditions. Sample pretreatment consisted of a first step using a quick, easy, cheap, effective, rugged, and safe based extraction procedure and a subsequent cleanup step based on solid-phase extraction. The method was extensively validated in wheat flour and rice, obtaining satisfactory analytical performance with good linearity (R(2) ≥ 0.999), acceptable recoveries (80.0-104.4%), and repeatability (RSDs 1.3-10.7%). The limits of detection (21.7-57.4 μg/kg) and quantitation (72.3-191.4 μg/kg) for deoxynivalenols were lower than those usually permitted by various countries' legislation in these food matrices. The method was applied to 34 wheat and rice samples. The results were further compared with results of ultra high performance liquid chromatography with electrospray ionization tandem mass spectrometry. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Analysis of Nitro-aromatic and Nitramine Explosives by Atmospheric Pressure Chemical Ionization / High Performance Liquid Chromatography / Mass Spectrometry / Mass Spectrometry

    International Nuclear Information System (INIS)

    Hicks, B.J.; Han, W.; Robben, J.R.

    2009-01-01

    This procedure is capable of separating and quantifying twenty-nine high explosives and internal surrogates with a single injection. After the initial preparation step, the sample is introduced to the high performance liquid chromatograph for target separation, ionized by atmospheric pressure chemical ionization and the explosives of interest are isolated / quantified by mass spectrometry / mass spectrometry. Concentrations of the target explosives are measured relative to the response of both internal and external standard concentrations. A C-18 reverse phase high performance liquid chromatograph column is used for separation. Ionization is performed using both positive and negative atmospheric pressure chemical ionization resulting in a molecular ion with little fragmentation. These ions are isolated at the first quadrupole of the mass spectrometer, dissociated by collision with argon in the collision cell and the resulting daughter ions are isolated at the second quadrupole. These daughter ions then reach the detector where they are quantified. To date this procedure represents the most thorough high performance liquid chromatography / mass spectrometry / mass spectrometry explosives analysis available in the environmental chemistry market. (authors)

  18. Comprehensive analysis of chemical constituents in Xingxiong injection by high performance liquid chromatography coupled with mass spectrometry.

    Science.gov (United States)

    Guo, Long; Dou, Li-Li; Duan, Li; Liu, Ke; Bi, Zhi-Ming; Li, Ping; Liu, E-Hu

    2015-09-01

    Xingxiong injection (XXI) is a widely used Chinese herbal formula prepared by the folium ginkgo extract and ligustrazine for the treatment of cardiovascular and cerebrovascular diseases. Compared with the pharmacological studies, chemical analysis and quality control studies on this formula are relatively limited. In the present study, a high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-QTOF MS) method was applied to comprehensive analysis of constituents in XXI. According to the fragmentation rules and previous reports, thirty ginkgo flavonoids, four ginkgo terpene lactones, and one alkaloid were identified. A high performance liquid chromatography coupled with triple quadrupole mass spectrometry (HPLC-QQQ MS) method was then applied to quantify ten major constituents in XXI. The method validation results indicated that the developed method had desirable specificity, linearity, precision and accuracy. The total contents of ginkgo flavonoids were about 22.05-25.51 μg·mL(-1) and the ginkgo terpene lactones amounts were about 4.41-8.70 μg·mL(-1) in six batches of XXI samples, respectively. Furthermore, cosine ratio algorithm and distance measurements were employed to evaluate the similarity of XXI samples, and the results demonstrated a high-quality consistency. This work could provide comprehensive information on the quality control of Xingxiong injection, which be helpful in the establishment of a rational quality control standard. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  19. Simultaneous determination of quinolones for veterinary use by high-performance liquid chromatography with electrochemical detection.

    Science.gov (United States)

    Rodríguez Cáceres, M I; Guiberteau Cabanillas, A; Galeano Díaz, T; Martínez Cañas, M A

    2010-02-01

    A selective method based on high-performance liquid chromatography with electrochemical detection (HPLC-ECD) has been developed to enable simultaneous determination of three fluoroquinolones (FQs), namely danofloxacin (DANO), difloxacin (DIFLO) and sarafloxacin (SARA). The fluoroquinolones are separated on a Novapack C-18 column and detected in a high sensitivity amperometric cell at a potential of +0.8 V. Solid-phase extraction was used for the extraction of the analytes in real samples. The range of concentration examined varied from 10 to 150 ng g(-1) for danofloxacin, from 25 to 100 ng g(-1) for sarafloxacin and from 50 to 315 ng g(-1) for difloxacin, respectively. The method presents detection limits under 10 ng g(-1) and recoveries around 90% for the three analytes have been obtained in the experiments with fortified samples. This HPLC-ECD approach can be useful in the routine analysis of antibacterial residues being less expensive and less complicated than other more powerful tools as hyphenated techniques. 2009 Elsevier B.V. All rights reserved.

  20. Analysis of serotonin concentrations in human milk by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Chiba, Takeshi; Maeda, Tomoji; Tairabune, Tomohiko; Tomita, Takashi; Sanbe, Atsushi; Takeda, Rika; Kikuchi, Akihiko; Kudo, Kenzo

    2017-03-25

    Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in milk volume homeostasis in the mammary gland during lactation; 5-HT in milk may also affect infant development. However, there are few reports on 5-HT concentrations in human breast milk. To address this issue, we developed a simple method based on high-performance liquid chromatography with fluorescence detection (HPLC-FD) for measuring 5-HT concentrations in human breast milk. Breast milk samples were provided by four healthy Japanese women. Calibration curves for 5-HT in each sample were prepared with the standard addition method between 5 and 1000 ng/ml, and all had correlation coefficients >0.999. The recovery of 5-HT was 96.1%-101.0%, with a coefficient of variation of 3.39%-8.62%. The range of 5-HT concentrations estimated from the calibration curves was 11.1-51.1 ng/ml. Thus, the HPLC-FD method described here can effectively extract 5-HT from human breast milk with high reproducibility. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Simultaneous determination of three purines in Alysicarpus vaginalis (L.) DC. by hollow fiber-based liquid-phase microextraction combined with high-performance liquid chromatography.

    Science.gov (United States)

    Liu, Hongjiao; Lei, Ming; Liang, Xiao; Jiang, Zhen; Guo, Xingjie

    2014-02-01

    In this paper, a three-phase hollow fiber liquid-phase microextraction (HF-LPME) method combined with high-performance liquid chromatography (HPLC) was developed for the determination of hypoxanthine (HX), xanthine (Xan) and adenine (A) and then for the first time successfully applied to the analysis of HX, Xan and A in Alysicarpus vaginalis (L.) DC. medicinal materials. Different factors affecting the HF-LPME procedure were investigated and optimized. Under optimal extraction conditions (1-octanol as organic solvent, pH of the donor and acceptor phase 10.0 and 3.5, respectively, extraction time 40 min, stirring rate 800 rpm and salt addition 10%, w/v), HX, Xan and A could be determined within the test ranges with a good correlation coefficient (r(2) > 0.9992). The limit of detection for HX, Xan and A was 153, 173 and 97 ng/mL, respectively, and the intra- and inter-day relative standard deviations were no more than 9.8%. The content of HX, Xan and A in Alysicarpus vaginalis (L.) DC. medicinal materials was 120.40, 18.37 and 62.75 µg/g, respectively. This procedure afforded a convenient, sensitive, accurate and inexpensive method with a high extraction efficiency for determination of HX, Xan and A. Copyright © 2013 John Wiley & Sons, Ltd.

  2. Determination of Alternaria mycotoxins in wine and juice using ionic liquid modified countercurrent chromatography as a pretreatment method followed by high-performance liquid chromatography.

    Science.gov (United States)

    Fan, Chen; Cao, Xueli; Liu, Man; Wang, Wei

    2016-03-04

    Alternariol (AOH), alternariol monomethyl ether (AME), and tenuazonic acid (TeA) are some of the main Alternaria mycotoxins that can be found as contaminants in food materials. The objective of this study was to develop a pretreatment method with countercurrent chromatography (CCC) for enrichment and cleanup of trace Alternaria mycotoxins in food samples prior to high-performance liquid chromatography (HPLC) analysis. An Analytical CCC instrument with a column volume 22.5mL was used, and a two-phase solvent system composed of ethyl acetate and water modified with 6% [HOOMIM][Cl] in mass to volume ratio was selected. Under the optimized CCC operation conditions, trace amounts of AOH, AME, and TeA in large volume of liquid sample were efficiently extracted and enriched in the stationary phase, and then eluted out just by reversing the stationary phase as mobile phase in the opposite flowing direction tail-to-head. The enrichment and elution strategies are unique and can be fulfilled online with high enrichment factors (87-114) and high recoveries (81.14-110.94%). The method has been successively applied to the determination of Alternaria mycotoxins in real apple juice and wine samples with the limits of detection (LOD) in the range of 0.03-0.14μgL(-1). Totally 12 wine samples and 15 apple juice samples from the local market were analyzed. The detection rate of AOH and AME in both kinds of the samples were more than 50%, while TeA was found in relatively high level of 1.75-49.61μgL(-1) in some of the apple juice samples. The proposed method is simple, rapid, and sensitive and could also be used for the analysis and monitoring of Alternaria mycotoxin in other food samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Cation exchange separation of 16 rare earth metals by microscale high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Ishii, D.; Hirose, A.; Iwasaki, Y.

    1978-01-01

    The separation of rare earth metals has been studied with a microcolumn of 0.5 mm i.d. and 75 mm length, packed with TSK LS-212 high-performance cation exchange resin. A micro-feeder (Model MF-2, from Azumadenki Kogyo) was used to drive carrier and sample solutions through the ion exchange column and detection cell. By combining a 250 μl syringe and a 0.5 mm i.d. sampling tube the micro-feeder, 0.1-1.0 μl rare earth metals were separated within 38 min, using only 304 μl of 0.4M α-hydroxy-isobutyric acid solution adjusted to pH 3.1-6.0 with ammonia solution as gradient carrier solution. The gradient elution was successfully performed by applying a new technique developed for microscale liquid chromatography. (author)

  4. Speciation analysis of cobalt in foods by high-performance liquid chromatography and neutron activation analysis

    International Nuclear Information System (INIS)

    Muto, Toshio; Koyama, Motoko

    1994-01-01

    A combined method by coupling high-performance liquid chromatography (HPLC, as a separation method) with neutron activation analysis (as a detection method) have been applied to the speciation analysis of cobalt in daily foods (e.g. egg, fish and milk). Cobalt species including free cobalt, vitamin B 12 and protein-bound cobalt were separated with a preparative HPLC and a centrifuge. Subsequently, the determination of cobalt in the separated species was made by neutron activation analysis. The results showed that the content of the total cobalt in the foods was found to lie in the range 0.4-11ng/g(0.4-11ppb) based on wet weight. The compositions of free cobalt, vitamin B 12 and protein-bound cobalt were ranged 16-43%, 55-73%, 2.3-17%, respectively. These experimental evidences suggest that the combination of HPLC and neutron activation analysis is expected to be a useful tool for speciation analysis of trace elements in biological as well as environmental materials. (author)

  5. Method Development and Validation for the Determination of Caffeine: An Alkaloid from Coffea arabica by High-performance Liquid Chromatography Method.

    Science.gov (United States)

    Naveen, P; Lingaraju, H B; Deepak, M; Medhini, B; Prasad, K Shyam

    2018-01-01

    The present study was investigated to develop and validate a reversed phase high performance liquid chromatography method for the determination of caffeine from bean material of Coffee arabica. The separation was achieved on a reversed-phase C18 column using a mobile phase composed of water: methanol (50:50) at a flow rate of 1.0 mlmin-1. The detection was carried out on a UV detector at 272 nm. The developed method was validated according to the requirements for International Conference on Harmonisation (ICH) guidelines, which includes specificity, linearity, precision, accuracy, limit of detection and limit of quantitation. The developed method validates good linearity with excellent correlation coefficient (R2 > 0.999). In repeatability and intermediate precision, the percentage relative standard deviation (% RSD) of peak area was less than 1% shows high precision of the method. The recovery rate for caffeine was within 98.78% - 101.28% indicates high accuracy of the method. The low limit of detection and limit of quantitation of caffeine enable the detection and quantitation of caffeine from C. arabica at low concentrations. The developed HPLC method is a simple, rapid, precisely, accurately and widely accepted and it is recommended for efficient assays in routine work. A simple, accurate, and sensitive high-performance liquid chromatography (HPLC) method for caffeine from Coffea arabica has been developed and validated. The developed HPLC method was validated for linearity, specificity, precision, recovery, limits of detection, and limits of quantification by the International Conference on Harmonization guidelines. The results revealed that the proposed method is highly reliable. This method could be successfully applied for routine quality work analysis. Abbreviation Used: C. arabica : Coffee arabica, ICH: International Conference on Harmonisation, % RSD: Percentage Relative Standard Deviation, R2: Correlation Coefficient, ppm: Parts per million, LOD: Limits

  6. Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry

    International Nuclear Information System (INIS)

    Mroczek, Tomasz; Ndjoko-Ioset, Karine; Glowniak, Kazimierz; Mietkiewicz-Capala, Agnieszka; Hostettmann, Kurt

    2006-01-01

    From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface on XTerra C 18 column using a gradient elution. Based on MS n spectra, 18 various alkaloids have been tentatively determined for the first time in this plant as the following types of structure: echimidine-N-oxide (three diasteroisomers), 7-sarracinyl-9-viridiflorylretronecine (two diasteroisomers), echimidine (two diasteroisomers), lycopsamine (two diasteroisomers), dihydroechinatine-N-oxide, dihydroheliospathuline-N-oxide, lycopsamine-N-oxide (three diasteroisomers), 7-acetyllycopsamine-N-oxide, symphytine-N-oxide (two diasteroisomers) and 2'',3''-epoxyechiumine-N-oxide

  7. Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mroczek, Tomasz [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland)]. E-mail: tmroczek@pharmacognosy.org; Ndjoko-Ioset, Karine [Laboratoire de Pharmacognosie et Phytochimie, Ecole de Pharmacie Geneve-Lausanne, Universite de Geneve, Quai Ernest-Ansermet 30, CH-1211 Geneva 4 (Switzerland); Glowniak, Kazimierz [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland); Mietkiewicz-Capala, Agnieszka [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland); Hostettmann, Kurt [Laboratoire de Pharmacognosie et Phytochimie, Ecole de Pharmacie Geneve-Lausanne, Universite de Geneve, Quai Ernest-Ansermet 30, CH-1211 Geneva 4 (Switzerland)

    2006-05-04

    From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface on XTerra C{sub 18} column using a gradient elution. Based on MS {sup n} spectra, 18 various alkaloids have been tentatively determined for the first time in this plant as the following types of structure: echimidine-N-oxide (three diasteroisomers), 7-sarracinyl-9-viridiflorylretronecine (two diasteroisomers), echimidine (two diasteroisomers), lycopsamine (two diasteroisomers), dihydroechinatine-N-oxide, dihydroheliospathuline-N-oxide, lycopsamine-N-oxide (three diasteroisomers), 7-acetyllycopsamine-N-oxide, symphytine-N-oxide (two diasteroisomers) and 2'',3''-epoxyechiumine-N-oxide.

  8. Analytical method for high resolution liquid chromatography for quality control French Macaw

    International Nuclear Information System (INIS)

    Garcia Penna, Caridad M; Torres Amaro, Leonid; Menendez Castillo, Rosa; Sanchez, Esther; Martinez Espinosa, Vivian; Gonzalez, Maria Lidia; Rodriguez, Carlos

    2007-01-01

    Was developed and validated an analytical method for high resolution liquid chromatography applicable to quality control of drugs dry French Macaw (Senna alata L. Roxb.) With ultraviolet detection at 340 nm. The method for high resolution liquid chromatography used to quantify the sennosides A and B, main components, was validated and proved to be specific, linear, precise and accurate. (Author)

  9. Ultra-high-performance liquid chromatography-tandem mass spectrometry measurement of climbazole deposition from hair care products onto artificial skin and human scalp

    NARCIS (Netherlands)

    Chen, G.; Hoptroff, M.; Fei, X.; Su, Y.; Janssen, H.-G.

    2013-01-01

    A sensitive and specific ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the measurement of climbazole deposition from hair care products onto artificial skin and human scalp. Deuterated climbazole was used as the internal

  10. Comprehensive sample analysis using high performance liquid chromatography with multi-detection.

    Science.gov (United States)

    Pravadali, Sercan; Bassanese, Danielle N; Conlan, Xavier A; Francis, Paul S; Smith, Zoe M; Terry, Jessica M; Shalliker, R Andrew

    2013-11-25

    Herein we assess the separation space offered by a liquid chromatography system with an optimised uni-dimensional separation for the determination of the key chemical entities in the highly complex matrix of a tobacco leaf extract. Multiple modes of detection, including UV-visible absorbance, chemiluminescence (acidic potassium permanganate, manganese(IV), and tris(2,2'-bipyridine)ruthenium(III)), mass spectrometry and DPPH radical scavenging were used in an attempt to systematically reduce the data complexity of the sample whilst obtaining a greater degree of molecule-specific information. A large amount of chemical data was obtained, but several limitations in the ability to assign detector responses to particular compounds, even with the aid of complementary detection systems, were observed. Thirty-three compounds were detected via MS on the tobacco extract and 12 out of 32 compounds gave a peak height ratio (PHR) greater than 0.33 on one or more detectors. This paper serves as a case study of these limitations, illustrating why multidimensional chromatography is an important consideration when developing a comprehensive chemical detection system. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Screening bioactive quality control markers of QiShenYiQi dripping pills based on the relationship between the ultra-high performance liquid chromatography fingerprint and vascular protective activity.

    Science.gov (United States)

    Zhuo, Limeng; Peng, Jingjing; Zhao, Yunli; Li, Dongxiang; Xie, Xiuman; Tong, Ling; Yu, Zhiguo

    2017-10-01

    Traditional Chinese medicine consists of complex phytochemical constituents. Selecting appropriate analytical markers of traditional Chinese medicine is a critical step in quality control. Currently, the combination of fingerprinting and efficacy evaluation is considered as a useful method for screening active ingredients in complex mixtures. This study was designed to develop an orthogonal partial least squares model for screening bioactive quality control markers of QishenYiqi dripping pills based on the fingerprint-efficacy relationship. First, the chemical fingerprints of 49 batches of QishenYiqi dripping pill samples were established by ultra-high performance liquid chromatography coupled with a photodiode array detector. Second, ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry was exploited to systematically investigate the 36 copossessing fingerprint components in QishenYiqi dripping pills. The vascular protective activity of QishenYiqi dripping pills was determined by using a cell counting kit-8 assay. Finally, fingerprint-efficacy relationship was established by orthogonal partial least squares model. The results indicated that ten components exhibited strong correlation with vascular protective activity, and these were preliminarily screened as quality control markers. The present study provided a novel idea for the study of the pharmacodynamic material basis and quality evaluation of QishenYiqi dripping pills. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Bioconversion of red ginseng saponins in the gastro-intestinal tract in vitro model studied by high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry

    NARCIS (Netherlands)

    Kong, H.; Wang, M.; Venema, K.; Maathuis, A.; Heijden, R. van der; Greef, J. van der; Xu, G.; Hankemeier, T.

    2009-01-01

    A high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry (HPLC-FTICR-MS) method was developed to investigate the metabolism of ginsenosides in in vitro models of the gastro-intestinal tract. The metabolites were identified by

  13. Binary Solvents Dispersive Liquid—Liquid Microextraction (BS-DLLME) Method for Determination of Tramadol in Urine Using High-Performance Liquid Chromatography

    Science.gov (United States)

    2014-01-01

    Background Tramadol is an opioid, synthetic analog of codeine and has been used for the treatment of acute or chronic pain may be abused. In this work, a developed Dispersive liquid liquid microextraction (DLLME) as binary solvents-based dispersive liquid-liquid microextraction (BS-DLLME) combined with high performance liquid chromatography (HPLC) with fluorescence detection (FD) was employed for determination of tramadol in the urine samples. This procedure involves the use of an appropriate mixture of binary extraction solvents (70 μL CHCl3 and 30 μL ethyl acetate) and disperser solvent (600 μL acetone) for the formation of cloudy solution in 5 ml urine sample comprising tramadol and NaCl (7.5%, w/v). After centrifuging, the small droplets of extraction solvents were precipitated. In the final step, the HPLC with fluorescence detection was used for determination of tramadol in the precipitated phase. Results Various factors on the efficiency of the proposed procedure were investigated and optimized. The detection limit (S/N = 3) and quantification limit (S/N = 10) were found 0.2 and 0.9 μg/L, respectively. The relative standard deviations (RSD) for the extraction of 30 μg L of tramadol was found 4.1% (n = 6). The relative recoveries of tramadol from urine samples at spiking levels of 10, 30 and 60 μg/L were in the range of 95.6 – 99.6%. Conclusions Compared with other methods, this method provides good figures of merit such as good repeatability, high extraction efficiency, short analysis time, simple procedure and can be used as microextraction technique for routine analysis in clinical laboratories. PMID:24495475

  14. Speciation of mercury in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography-inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Jia Xiaoyu; Han Yi; Liu Xinli; Duan Taicheng; Chen Hangting

    2011-01-01

    The dispersive liquid-liquid microextraction (DLLME) combined with high performance liquid chromatography-inductively coupled plasma mass spectrometry for the speciation of mercury in water samples was described. Firstly methylmercury (MeHg + ) and mercury (Hg 2+ ) were complexed with sodium diethyldithiocarbamate, and then the complexes were extracted into carbon tetrachloride by using DLLME. Under the optimized conditions, the enrichment factors of 138 and 350 for MeHg + and Hg 2+ were obtained from only 5.00 mL sample solution. The detection limits of the analytes (as Hg) were 0.0076 ng mL -1 for MeHg + and 0.0014 ng mL -1 for Hg 2+ , respectively. The relative standard deviations for ten replicate measurements of 0.5 ng mL -1 MeHg + and Hg 2+ were 6.9% and 4.4%, respectively. Standard reference material of seawater (GBW(E)080042) was analyzed to verify the accuracy of the method and the results were in good agreement with the certified values. Finally, the developed method was successfully applied for the speciation of mercury in three environmental water samples.

  15. Dehydroepiandrosterone sulfate quantification in serum using high-performance liquid chromatography/mass spectrometry and a deuterated internal standard: a technique suitable for routine use or as a reference method

    International Nuclear Information System (INIS)

    Shackleton, C.H.; Kletke, C.; Wudy, S.; Pratt, J.H.

    1990-01-01

    A thermospray high-performance liquid chromatography/mass spectrometry method for determination of serum dehydroepiandrosterone sulfate is described. The steroid was measured intact using [7,7-2H2]dehydroepiandrosterone sulfate as internal standard. The analysis was carried out in the negative ion mode by determining the peak height ratio of the molecular anions of the analyte and internal standard. The method was used to determine the steroid in serum from 15 male and female normal adults and the following values were obtained: males, 272 +/- 45 micrograms/dl (range, 197 to 331 micrograms/dl) and females, 215 +/- 67 micrograms/dl (range, 107 to 347 micrograms/dl). In addition, dehydroepiandrosterone sulfate was measured by high-performance liquid chromatography/mass spectrometry and radioimmunoassay (a commercial kit) on 25 individuals of all age groups. There was strong correlation between the values obtained, but the radioimmunoassay values were generally double those obtained by high-performance liquid chromatography/mass spectrometry. Three other steroid sulfates, androsterone sulfate, epiandrosterone sulfate, and androst-5-ene-3 beta, 17 beta-diol sulfate, were also assayed. In males, these had mean values of 112, 44, and 13 micrograms/dl and, in females, they had mean values of 84, 25, and 6 micrograms/dl, respectively. Radioimmunoassay cross-reactivity measurement for these steroids (as reference compounds) showed that they were unlikely to contribute greatly to the discrepancy between radioimmunoassay and high-performance liquid chromatography/mass spectrometry values

  16. Investigation into the temporal stability of aqueous standard solutions of psilocin and psilocybin using high performance liquid chromatography.

    Science.gov (United States)

    Anastos, N; Barnett, N W; Pfeffer, F M; Lewis, S W

    2006-01-01

    This paper reports an investigation into the temporal stability of aqueous solutions of psilocin and psilocybin reference drug standards over a period of fourteen days. This study was performed using high performance liquid chromatography utilising a (95:5% v/v) methanol: 10 mM ammonium formate, pH 3.5 mobile phase and absorption detection at 269 nm. It was found that the exclusion of light significantly prolonged the useful life of standards, with aqueous solutions of both psilocin and psilocybin being stable over a period of seven days.

  17. Multi-detection of corticosteroids in sports doping and veterinary control using high-resolution liquid chromatography/time-of-flight mass spectrometry

    NARCIS (Netherlands)

    Touber, M.E.; Engelen, M.C.; Georgakopoulus, C.; Rhijn, van J.A.; Nielen, M.W.F.

    2007-01-01

    A liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS) method was developed using the latest high-resolution LC column technology, the ultra performance liquid chromatography (UPLC (TM)), and electrospray ionization (ESI) in the positive ion mode. Gradient UPLC separation conditions

  18. Microwave-assisted ionic liquid homogeneous liquid-liquid microextraction coupled with high performance liquid chromatography for the determination of anthraquinones in Rheum palmatum L.

    Science.gov (United States)

    Wang, Zhibing; Hu, Jianxue; Du, Hongxia; He, Shuang; Li, Qing; Zhang, Hanqi

    2016-06-05

    The microwave-assisted ionic liquid homogeneous liquid-liquid microextraction (MA-IL-HLLME) coupled with high performance liquid chromatography with diode array detection (HPLC-DAD) was developed for the determination of anthraquinones, including aloe-emodin, emodin, chrysophanol and physcion in root of Rheum palmatum L. Several experimental parameters influencing the extraction efficiency, including amount of sample, type and volume of ionic liquid, volume and pH value of extraction medium, microwave power and extraction time, concentration of NH4PF6 as well as centrifugal condition were optimized. When 140μL of ionic liquid ([C8MIM][BF4]) was used as an extraction solvent, target analytes can be extracted from sample matrix in one minute with the help of microwave irradiation. The MA-IL-HLLME is simple and quick. The calibration curves exhibited good linear relationship (r>0.9984). The limits of detection and quantification were in the range of 0.015-0.026 and 0.051-0.088μgmL(-1), respectively. The spiked recovery for each analyte was in the range of 81.13-93.07% with relative standard deviations lower than 6.89%. The present method is free of volatile organic solvents, and represents lower expenditures of sample, extraction time and solvent, compared with ultrasonic and heat reflux extraction. The results indicated that the present method can be successfully applied to the determination of anthraquinones in medicinal plant. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Ionic liquid as a mobile phase additive in high-performance liquid chromatography for the simultaneous determination of eleven fluorescent whitening agents in paper materials.

    Science.gov (United States)

    Wang, Qing; Chen, Xianbo; Qiu, Bin; Zhou, Liang; Zhang, Hui; Xie, Juan; Luo, Yan; Wang, Bin

    2016-04-01

    In the present study, 11 4,4'-diaminostilbene-2,2'-disulfonic acid based fluorescent whitening agents with different numbers of sulfonic acid groups were separated by using an ionic liquid as a mobile phase additive in high-performance liquid chromatography with fluorescence detection. The effects of ionic liquid concentration, pH of mobile phase B, and composition of mobile phase A on the separation of fluorescent whitening agents were systematically investigated. The ionic liquid tetrabutylammonium tetrafluoroborate is superior to tetrabutylammomnium bromide for the separation of the fluorescent whitening agents. The optimal separation conditions were an ionic liquid concentration at 8 mM and the pH of mobile phase B at 8.5 with methanol as mobile phase A. The established method exhibited low limits of detection (0.04-0.07 ng/mL) and wide linearity ranges (0.30-20 ng/mL) with high linear correlation coefficients from 0.9994 to 0.9998. The optimized procedure was applied to analyze target analytes in paper samples with satisfactory results. Eleven target analytes were quantified, and the recoveries of spiked paper samples were in the range of 85-105% with the relative standard deviations from 2.1 to 5.1%. The obtained results indicated that the method was efficient for detection of 11 fluorescent whitening agents. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Fingerprint analysis and quality consistency evaluation of flavonoid compounds for fermented Guava leaf by combining high-performance liquid chromatography time-of-flight electrospray ionization mass spectrometry and chemometric methods.

    Science.gov (United States)

    Wang, Lu; Tian, Xiaofei; Wei, Wenhao; Chen, Gong; Wu, Zhenqiang

    2016-10-01

    Guava leaves are used in traditional herbal teas as antidiabetic therapies. Flavonoids are the main active of Guava leaves and have many physiological functions. However, the flavonoid compositions and activities of Guava leaves could change due to microbial fermentation. A high-performance liquid chromatography time-of-flight electrospray ionization mass spectrometry method was applied to identify the varieties of the flavonoids in Guava leaves before and after fermentation. High-performance liquid chromatography, hierarchical cluster analysis and principal component analysis were used to quantitatively determine the changes in flavonoid compositions and evaluate the consistency and quality of Guava leaves. Monascus anka Saccharomyces cerevisiae fermented Guava leaves contained 2.32- and 4.06-fold more total flavonoids and quercetin, respectively, than natural Guava leaves. The flavonoid compounds of the natural Guava leaves had similarities ranging from 0.837 to 0.927. The flavonoid compounds from the Monascus anka S. cerevisiae fermented Guava leaves had similarities higher than 0.993. This indicated that the quality consistency of the fermented Guava leaves was better than that of the natural Guava leaves. High-performance liquid chromatography fingerprinting and chemometric analysis are promising methods for evaluating the degree of fermentation of Guava leaves based on quality consistency, which could be used in assessing flavonoid compounds for the production of fermented Guava leaves. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. A high-performance liquid chromatography method for the serotonin release assay is equivalent to the radioactive method.

    Science.gov (United States)

    Sono-Koree, N K; Crist, R A; Frank, E L; Rodgers, G M; Smock, K J

    2016-02-01

    The serotonin release assay (SRA) is considered the gold standard laboratory test for heparin-induced thrombocytopenia (HIT). The historic SRA method uses platelets loaded with radiolabeled serotonin to evaluate platelet activation by HIT immune complexes. However, a nonradioactive method is desirable. We report the performance characteristics of a high-performance liquid chromatography (HPLC) SRA method. We validated the performance characteristics of an HPLC-SRA method, including correlation with a reference laboratory using the radioactive method. Serotonin released from reagent platelets was quantified by HPLC using fluorescent detection. Results were expressed as % release and classified as positive, negative, or indeterminate based on previously published cutoffs. Serum samples from 250 subjects with suspected HIT were tested in the HPLC-SRA and with the radioactive method. Concordant classifications were observed in 230 samples (92%). Sera from 41 healthy individuals tested negative. Between-run imprecision studies showed standard deviation of performance characteristics, equivalent to the historic radioactive method, but avoids the complexities of working with radioactivity. © 2015 John Wiley & Sons Ltd.

  2. New approach to the determination phosphorothioate oligonucleotides by ultra high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Studzińska, Sylwia; Mounicou, Sandra; Szpunar, Joanna; Łobiński, Ryszard; Buszewski, Bogusław

    2015-01-15

    This text presents a novel method for the separation and detection of phosphorothioate oligonucleotides with the use of ion pair ultra high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry The research showed that hexafluoroisopropanol/triethylamine based mobile phases may be successfully used when liquid chromatography is coupled with such elemental detection. However, the concentration of both HFIP and TEA influences the final result. The lower concentration of HFIP, the lower the background in ICP-MS and the greater the sensitivity. The method applied for the analysis of serum samples was based on high resolution inductively coupled plasma mass spectrometry. Utilization of this method allows determination of fifty times lower quantity of phosphorothioate oligonucleotides than in the case of quadrupole mass analyzer. Monitoring of (31)P may be used to quantify these compounds at the level of 80 μg L(-1), while simultaneous determination of sulfur is very useful for qualitative analysis. Moreover, the results presented in this paper demonstrate the practical applicability of coupling LC with ICP-MS in determining phosphorothioate oligonucleotides and their metabolites in serum within 7 min with a very good sensitivity. The method was linear in the concentration range between 0.2 and 3 mg L(-1). The limit of detection was in the range of 0.07 and 0.13 mg L(-1). Accuracy varied with concentration, but was in the range of 3%. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Analysis of Caffeic Acid Extraction From Ocimum gratissimum Linn. by High Performance Liquid Chromatography and its Effects on a Cervical Cancer Cell Line

    Directory of Open Access Journals (Sweden)

    Je-Chiuan Ye

    2010-09-01

    Conclusion: This paper shows that high performance liquid chromatography is a suitable analytical method for determining caffeic acid levels in O. gratissimum, Ju ZenTa, and several vegetable oils. Caffeic acid can suppress the proliferation of HeLa cells.

  4. Validation of a technique by high-performance liquid chromatography for the determination of total isoflavones

    Directory of Open Access Journals (Sweden)

    Pilar A. Soledispa Cañarte

    2017-04-01

    Full Text Available Context: Isoflavones may act as selective regulators in the prevention of various diseases. The most important source of isoflavones is the soy, from which different phytotherapeutics are elaborated of use in Ecuadorian population. However, its concentration varies depending on several factors, therefore quality assessment need to be carried out through out several analytical methods. Aims: To validate an analytical method by high precision liquid chromatography (HPLC to quantify total isoflavones in herbal medicine. Methods: To quantify isoflavones, it was used a brand liquid chromatography with UV/VIS detector at 260 nm, C-18 column using isocratic method. The mobile phase was composed of 2% acetic acid: acetonitrile (75:25. The quantification was performed against reference standard. The parameters for the validation followed the established in the USP 33. Results: The chromatogram presented six peaks with elution between 1.557 and 18.913 min. The linearity of the system and the method got r2 equal to 0.98 and 0.99 respectively. The coefficients of variation 1.5% in the study of repetitiveness and 2% in intermediate precision. The accuracy of the adjusted lineal model exhibited r=0.95 and intercept reliable interval (-0.921; 1.743. Conclusions: The validated method was specific, accurate, precise and linear. It can be used for quality control and stability studies of isoflavones present in herbal medicine.

  5. Selective on-line detection of boronic acids and derivatives in high-performance liquid chromatography eluates by post-column reaction with alizarin

    NARCIS (Netherlands)

    Duval, F.L.; Wardani, P.A.; Zuilhof, H.; Beek, van T.A.

    2015-01-01

    An on-line high-performance liquid chromatography (HPLC) method for the rapid and selective detection of boronic acids in complex mixtures was developed. After optimization experiments at an HPLC flow rate of 0.40 mL/min, the HPLC-separated analytes were mixed post-column with a solution of 75 µM

  6. Ionic-liquid-based dispersive liquid-liquid microextraction combined with magnetic solid-phase extraction for the determination of aflatoxins B1 , B2 , G1 , and G2 in animal feeds by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Zhao, Jiao; Zhu, Yan; Jiao, Yang; Ning, Jinyan; Yang, Yaling

    2016-10-01

    A novel two-step extraction technique combining ionic-liquid-based dispersive liquid-liquid microextraction with magnetic solid-phase extraction was developed for the preconcentration and separation of aflatoxins in animal feedstuffs before high-performance liquid chromatography coupled with fluorescence detection. In this work, ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate was used as the extractant in dispersive liquid-liquid microextraction, and hydrophobic pelargonic acid modified Fe 3 O 4 magnetic nanoparticles as an efficient adsorbent were applied to retrieve the aflatoxins-containing ionic liquid. Notably, the target of magnetic nanoparticles was the ionic liquid rather than the aflatoxins. Because of the rapid mass transfer associated with the dispersive liquid-liquid microextraction and magnetic solid phase steps, fast extraction could be achieved. The main parameters affecting the extraction recoveries of aflatoxins were investigated and optimized. Under the optimum conditions, vortexing at 2500 rpm for 1 min in the dispersive liquid-liquid microextraction and magnetic solid-phase extraction and then desorption by sonication for 2 min with acetonitrile as eluent. The recoveries were 90.3-103.7% with relative standard deviations of 3.2-6.4%. Good linearity was observed with correlation coefficients ranged from 0.9986 to 0.9995. The detection limits were 0.632, 0.087, 0.422 and 0.146 ng/mL for aflatoxins B 1 , B2, G1, and G2, respectively. The results were also compared with the pretreatment method carried out by conventional immunoaffinity columns. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Simultaneous determination of caffeine, theobromine, and theophylline by high-performance liquid chromatography.

    Science.gov (United States)

    Bispo, Marcia S; Veloso, Márcia Cristina C; Pinheiro, Heloísa Lúcia C; De Oliveira, Rodolfo F S; Reis, José Oscar N; De Andrade, Jailson B

    2002-01-01

    This work relates the development of an analytical methodology to simultaneously determine three methylxanthines (caffeine, theobromine, and theophylline) in beverages and urine samples based on reversed-phase high-performance liquid chromatography. Separation is made with a Bondesil C18 column using methanol-water-acetic acid or ethanol-water-acetic acid (20:75:5, v/v/v) as the mobile phase at 0.7 mL/min. Identification is made by absorbance detection at 273 nm. Under optimized conditions, the detection limit of the HPLC method is 0.1 pg/mL for all three methylxanthines. This method is applied to urine and to 25 different beverage samples, which included coffee, tea, chocolate, and coconut water. The concentration ranges determined in the beverages and urine are: < 0.1 pg/mL to 350 microg/mL and 3.21 microg/mL to 71.2 microg/mL for caffeine; < 0.1 pg/mL to 32 microg mL and < 0.1 pg/mL to 13.2 microg/mL for theobromine; < 0.1 pg/mL to 47 microg/mL and < 0.1 pg/mL to 66.3 microg/mL for theophylline. The method proposed in this study is rapid and suitable for the simultaneous quantitation of methylxanthines in beverages and human urine samples and requires no extraction step or derivatization.

  8. Separation of amino acids and antibiotics by narrow-bore and normal-bore high-performance liquid chromatography with pre-column derivatization.

    Science.gov (United States)

    Fiedler, H P; Plaga, A

    1987-01-16

    The selectivity, efficiency and lifetime of normal- and narrow-bore columns for high-performance liquid chromatography were investigated for the separation and quantification of amino acids and the amino acid-like antibiotics phosphinothricin and phosphinothricylalanylalanine in biological samples. These compounds were determined by an automated pre-column derivatization with o-phthalaldehyde-2-mercaptoethanol reagent and UV detection at 338 nm.

  9. The simple and sensitive measurement of malondialdehyde in selected specimens of biological origin and some feed by reversed phase high performance liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Czauderna, M.; Kowalczyk, J.; Marounek, Milan

    2011-01-01

    Roč. 879, č. 23 (2011), s. 2251-2258 ISSN 1570-0232 Institutional research plan: CEZ:AV0Z50450515 Keywords : Malondialdehyde * 2,4-Dinitrophenylhydrazine * High performance liquid chromatography Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.888, year: 2011

  10. Characterisation of uremic "Middle molecular"fractions by gas chromatography mass spectrometry, isotachophoresis, and liquid chromatography

    NARCIS (Netherlands)

    Schoots, A.C.; Mikkers, F.E.P.; Claessens, H.A.; Smet, de R.; Landschoot, van N.; Ringoir, S.M.G.

    1982-01-01

    Uremic ultrafiltrates (and normal serum, for comparison) were fractionated by means of gel filtration. The collected fractions were further investigated by combined analytical techniques: "high- performance" liquid chromatography, gas chromatography, mass spectrometry, and isotachophoresis.

  11. High-performance Liquid Chromatographic Ultraviolet Detection of Nilotinib in Human Plasma from Patients with Chronic Myelogenous Leukemia, and Comparison with Liquid Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    Nakahara, Ryosuke; Satho, Yuhki; Itoh, Hiroki

    2016-11-01

    A method for determining nilotinib concentration in human plasma is proposed using high-performance liquid chromatography and ultraviolet detection. Nilotinib and the internal standard dasatinib were separated using a mobile phase of 0.5% Na 2 PO 4 H 2 O (pH 2.5)-acetonitrile-methanol (55:25:20, v/v/v) on a Capcell Pak C18 MG II column (250 × 4.6 mm) at a flow rate of 1.0 ml/min, and ultraviolet measurement at 250 nm. The calibration curve exhibited linearity over the nilotinib concentration range of 50-2,500 ng/ml at 250 nm, with relative standard deviations (n = 5) of 7.1%, 2.5%, and 2.9% for 250, 1,500, and 2,500 ng/ml, respectively. The detection limit for nilotinib was 5 ng/ml due to three blank determinations (ρ = 3). This method was successfully applied to assaying nilotinib in human plasma samples from patients with chronic myelogenous leukemia. In addition, we compared the results with those measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) at BML, Inc. (a commercial laboratory). A strong correlation was observed between the nilotinib concentrations measured by our high-performance liquid chromatographic method and those obtained by LC/MS-MS (r 2 = 0.988, P < 0.01). © 2016 Wiley Periodicals, Inc.

  12. Analysis of aromatic amines in water samples by liquid-liquid-liquid microextraction with hollow fibers and high-performance liquid chromatography.

    Science.gov (United States)

    Zhao, Limian; Zhu, Lingyan; Lee, Hian Kee

    2002-07-19

    Liquid-liquid-liquid microextraction (LLLME) with hollow fibers in high-performance liquid chromatography (HPLC) has been applied as a rapid and sensitive quantitative method for the detection of four aromatic amines (3-nitroaniline, 4-chloroaniline, 4-bromoaniline and 3,4-dichloroaniline) in environmental water samples. The preconcentration procedure was induced by the pH difference inside and outside the hollow fiber. The target compounds were extracted from 4-ml aqueous sample (donor solution, pH approximately 13) through a microfilm of organic solvent (di-n-hexyl ether), immobilized in the pores of a hollow fiber (1.5 cm length x 0.6 mm I.D.), and finally into 4 microl of acid acceptor solution inside the fiber. After a prescribed period of time, the acceptor solution inside the fiber was withdrawn into the microsyringe and directly injected into the HPLC system for analysis. Factors relevant to the extraction procedure were studied. Up to 500-fold enrichment of analytes could be obtained under the optimized conditions (donor solution: 0.1 M sodium hydroxide solution with 20% sodium chloride and 2% acetone; organic phase: di-n-hexyl ether; acceptor solution: 0.5 M hydrochloric acid and 500 mM 18-crown-6 ether; extraction time of 30 min; stirring at 1,000 rev./min). The procedure also served as a sample clean-up step. The influence of humic acid on the extraction efficiency was also investigated, and more than 85% relative recoveries of the analytes at two different concentrations (20 and 100 microg/l) were achieved at various concentration of humic acid. This technique is a low cost, simple and fast approach to the analysis of polar compounds in aqueous samples.

  13. Blind column selection protocol for two-dimensional high performance liquid chromatography.

    Science.gov (United States)

    Burns, Niki K; Andrighetto, Luke M; Conlan, Xavier A; Purcell, Stuart D; Barnett, Neil W; Denning, Jacquie; Francis, Paul S; Stevenson, Paul G

    2016-07-01

    The selection of two orthogonal columns for two-dimensional high performance liquid chromatography (LC×LC) separation of natural product extracts can be a labour intensive and time consuming process and in many cases is an entirely trial-and-error approach. This paper introduces a blind optimisation method for column selection of a black box of constituent components. A data processing pipeline, created in the open source application OpenMS®, was developed to map the components within the mixture of equal mass across a library of HPLC columns; LC×LC separation space utilisation was compared by measuring the fractional surface coverage, fcoverage. It was found that for a test mixture from an opium poppy (Papaver somniferum) extract, the combination of diphenyl and C18 stationary phases provided a predicted fcoverage of 0.48 and was matched with an actual usage of 0.43. OpenMS®, in conjunction with algorithms designed in house, have allowed for a significantly quicker selection of two orthogonal columns, which have been optimised for a LC×LC separation of crude extractions of plant material. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Determination of catechin in lotus rhizomes by high-performance liquid chromatography.

    Science.gov (United States)

    Yan, Shou-Lei; Wang, Qing-Zhang; Peng, Guang-Hua

    2009-08-01

    A novel method was developed to analyze lotus rhizome polyphenolic catechin using high-performance liquid chromatography (HPLC). The retain time of catechin was 14.72 min under the optimized condition. Mass spectrometry was further employed to qualify and quantify the purity of the catechin peak. Good linearity (R=0.9997) was obtained within the range of 50-1,000 ng. The coefficient of variance was determined as 5.2%, with a recovery rate of 97%. The detection and quantification limitations of catechin were 23 ng and 50 ng, respectively. The catechin level was 0.0025% in the lotus rhizome, and 0.011% in the knot of the lotus rhizome (Nelumbo nucifera cv. 'damao jie'). The optimized conditions of HPLC for catechin detection in the lotus rhizome matrix were as follows: the SuperlcosIL™ LC-18 analytical column (150 mm×4.6 mm, 5 µm), methanol-water-acetic acid (10:90:1, volume ratio) as the mobile phase, an UV detector at 280 nm, a flow rate of 0.8 ml/min, column temperature at 30°C, and an injection volume of 10 µl.

  15. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses.

    Science.gov (United States)

    Muthukrishnan, Suriyavathana; Palanisamy, Subha; Subramanian, Senthilkumar; Selvaraj, Sumathi; Mari, Kavitha Rani; Kuppulingam, Ramalingam

    2016-08-01

    Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV) were identified by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GC-MS) analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy) tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases. Copyright © 2016. Published by Elsevier B.V.

  16. Solid-Phase Extraction Combined with High Performance Liquid ...

    African Journals Online (AJOL)

    Methods: Solid-phase extraction method was employed for the extraction of the estrogen from milk and high performance liquid chromatography-diode array detector (HPLC-DAD) was used for the determination of estrogen. Results: Optimal chromatographic conditions were achieved on an Eclipse XDB-C18 column at a ...

  17. Identification of Ginkgo biloba supplements adulteration using high performance thin layer chromatography and ultra high performance liquid chromatography-diode array detector-quadrupole time of flight-mass spectrometry.

    Science.gov (United States)

    Avula, Bharathi; Sagi, Satyanarayanaraju; Gafner, Stefan; Upton, Roy; Wang, Yan-Hong; Wang, Mei; Khan, Ikhlas A

    2015-10-01

    Ginkgo biloba is one of the most widely sold herbal supplements and medicines in the world. Its popularity stems from having a positive effect on memory and the circulatory system in clinical studies. As ginkgo popularity increased, non-proprietary extracts were introduced claiming to have a similar phytochemical profile as the clinically tested extracts. The standardized commercial extracts of G. biloba leaf used in ginkgo supplements contain not less than 6% sesquiterpene lactones and 24% flavonol glycosides. While sesquiterpene lactones are unique constituents of ginkgo leaf, the flavonol glycosides are found in many other botanical extracts. Being a high value botanical, low quality ginkgo extracts may be subjected to adulteration with flavonoids to meet the requirement of 24% flavonol glycosides. Chemical analysis by ultra high performance liquid chromatography-mass spectrometry revealed that adulteration of ginkgo leaf extracts in many of these products is common, the naturally flavonol glycoside-rich extract being spiked with pure flavonoids or extracts made from another flavonoid-rich material, such as the fruit/flower of Japanese sophora (Styphnolobium japonicum), which also contains the isoflavone genistein. Recently, genistein has been proposed as an analytical marker for the detection of adulteration of ginkgo extracts with S. japonicum. This study confirms that botanically authenticated G. biloba leaf and extracts made therefrom do not contain genistein, and the presence of which even in trace amounts is suggestive of adulteration. In addition to the mass spectrometric approach, a high performance thin layer chromatography method was developed as a fast and economic method for chemical fingerprint analysis of ginkgo samples.

  18. [Determination of aspirin and free salicylic acid in lysinipirine injection by high performance liquid chromatography].

    Science.gov (United States)

    Dong, Yu; Zhao, Yuan-zheng; Zhang, Yi-na

    2002-05-01

    The contents of aspirin and free salicylic acid in lysinipirine injection were determined by high performance liquid chromatography (HPLC). A Hypersil BDS C18 column was used with the mobile phase of methanol-water-acetic acid (35:65:3, volume ratio) and the detection wavelength of 280 nm. The average recoveries of aspirin and salicylic acid added were 99.27% (RSD = 0.8%) and 99.61%(RSD = 1.3%), respectively. The calibration curves had good linearity in the range of 0.028 g/L -0.141 mg/L and 0.77 mg/L -3.85 mg/L, and the correlation coefficients were 0.9999 and 0.9998 for aspirin and salicylic acid respectively.

  19. Determination of free urinary cortisol in cushing's syndrome using reversed-phase high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Eduardo Kinio Sugawara

    2010-01-01

    Full Text Available Determination of free urinary cortisol is a test of choice in the diagnosis of Cushing's syndrome. In this study, cortisol was quantified using reversed-phase high-performance liquid chromatography (RP-HPLC in urine samples previously extracted with ether and using triamcinolone acetonide as internal standard (IS. A BDS-Hypersil-C18® column, water-acetonitrile (72:28; v/v, with a flow rate of 1.0 mL/min and detection at 243 nm were used. This method showed to be both effective and efficient, with sensitivity and linearity ranging from 2.50 to 150 μg/L, and can be used in substitution to the radioimmunoassay technique within this concentration range.

  20. Chiral ligand exchange high-speed countercurrent chromatography: mechanism, application and comparison with conventional liquid chromatography in enantioseparation of aromatic α-hydroxyl acids

    Science.gov (United States)

    Tong, Shengqiang; Shen, Mangmang; Cheng, Dongping; Ito, Yoichiro; Yan, Jizhong

    2014-01-01

    This work concentrates on the separation mechanism and application of chiral ligand exchange high-speed countercurrent chromatography (HSCCC) in enantioseparations, and comparison with traditional chiral ligand exchange high performance liquid chromatography (HPLC). The enantioseparation of ten aromatic α-hydroxyl acids were performed by these two chromatographic methods. Results showed that five of the racemates were successfully enantioseparated by HSCCC while only three of the racemates could be enantioseparated by HPLC using a suitable chiral ligand mobile phase additive. For HSCCC, the two-phase solvent system was composed of butanol-water (1:1, v/v), to which N-n-dodecyl-L-proline was added in the organic phase as chiral ligand and cupric acetate was added in the aqueous phase as a transition metal ion. Various operation parameters in HSCCC were optimized by enantioselective liquid-liquid extraction. Based on the results of the present studies the separation mechanism for HSCCC was proposed. For HPLC, the optimized mobile phase composed of aqueous solution containing 6 mmol L−1 L-phenylalanine and 3 mmol L−1 cupric sulfate and methanol was used for enantioseparation. Among three ligands tested on a conventional reverse stationary phase column, only one was found to be effective. In the present studies HSCCC presented unique advantages due to its high versatility of two-phase solvent systems and it could be used as an alternative method for enantioseparations. PMID:25087742

  1. Quantitative analysis of pharmaceuticals in biological fluids using high-performance liquid chromatography coupled to mass spectrometry: a review.

    Science.gov (United States)

    Plumb, R S; Dear, G J; Mallett, D N; Higton, D M; Pleasance, S; Biddlecombe, R A

    2001-01-01

    1. The development of bio-analysis of drug molecules over the last 10 years is reviewed, focusing on advances in sample preparation, liquid chromatography and detection. 2. Developments have led to improvements in detection sensitivity, enhancements in specificity and increased capacity. 3. Emerging technologies such as monolithic column chromatography and miniaturized chip-based systems are discussed.

  2. Determination of 6-mercaptopurine and azathioprine in plasma by high-performance liquid chromatography.

    Science.gov (United States)

    Ding, T L; Benet, L Z

    1979-07-21

    Using 1-ml plasma samples, levels of 6-mercaptopurine (6MP) as low as 5 ng/ml and azathioprine (AZA) as low as 40 ng/ml can be detected using a high-performance liquid chromatography reversed-phase column procedure following extraction. Both compounds were stable in frozen plasma for seven weeks. AZA stability in blood was temperature dependent; the half-lives of AZA breakdown to 6MP at 37 degrees were 28 and 46 min in blood drawn from two rhesus monkeys. Plasma levels of 6MP were measured in a rhesus monkey following 6MP (1.47 mg/kg) and AZA (3 mg/kg) intravenous administration. 6MP levels were also measured in three renal transplant patients on daily 50- and 100-mg AZA doses. Peak levels (45-75 ng/ml) were reached within an hour and 6MP levels were detected for up to 7 h.

  3. Determination of five antiarrhythmic drugs in human plasma by dispersive liquid-liquid microextraction and high-performance liquid chromatography.

    Science.gov (United States)

    Jouyban, Abolghasem; Sorouraddin, Mohammad Hossein; Farajzadeh, Mir Ali; Somi, Mohammad Hossein; Fazeli-Bakhtiyari, Rana

    2015-03-01

    A fast and sensitive high-performance liquid chromatography (HPLC) method with ultraviolet (UV) detection was developed and validated for the simultaneous quantitation of five antiarrhythmic drugs (metoprolol, propranolol, carvedilol, diltiazem, and verapamil) in human plasma samples. It involves dispersive liquid-liquid microextraction (DLLME) of the desired drugs from 660 µL plasma and separation using isocratic elution with UV detection at 200 nm. The complete separation of all analytes was achieved within 7 min. Acetonitrile (as disperser solvent) resulting from the protein precipitation procedure was mixed with 100 µL dichloromethane (as an extraction solvent) and rapidly injected into 5 mL aqueous solution (pH 11.5) containing 1% (w/v), NaCl. After centrifugation, the sedimented phase containing enriched analytes was collected and evaporated to dryness. The residue was re-dissolved in 50 µL de-ionized water (acidified to pH 3) and injected into the HPLC system for analysis. Under the optimal conditions, the enrichment factors and extraction recoveries ranged between 4.4-10.8 and 33-82%, respectively. The suggested method was linear (r(2) ≥0.997) over a dynamic range of 0.02-0.80 µg mL(-1) in plasma. The intra- and inter-days relative standard deviation (RSD%) and relative error (RE%) values of the method were below 20%, which shows good precision and accuracy. Finally, this method was applied to the analysis of real plasma samples obtained from the patients treated with these drugs. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Optimization and development of a high-performance liquid chromatography-based one-site immunometric assay with chemiluminescence detection

    International Nuclear Information System (INIS)

    Oates, Matthew R.; Clarke, William; Zimlich, Alden; Hage, David S.

    2002-01-01

    Various practical and theoretical considerations were examined in the creation and optimization of a high-performance liquid chromatography (HPLC)-based one-site immunometric assay. This method used an HPLC analyte analog column and post-column chemiluminescence detection. The specific analyte chosen as the model for this study was L-thyroxine (also known as T 4 ). In this technique, a sample containing thyroxine was first combined with an excess of anti-T 4 antibody Fab fragments that had earlier been conjugated with chemiluminescent acridinium ester labels. After incubation, the mixture was injected onto a column that contained immobilized T 4 . The amount of thyroxine in the original sample was then determined by measuring the labeled Fab fragments that appeared in the non-retained fraction, or the decrease in excess Fab fragments that were bound to and later eluted from the column. Items considered in creating this assay included the preparation of acridinium ester-labeled Fab fragments, the detection of these fragments with a post-column reactor, and the creation of a suitable immobilized analog column for capturing excess labeled Fab fragments. The final method could measure T 4 in standards at clinically-relevant concentrations and provided a response within 1.5 min of sample injection, following a 20-45 min incubation with the labeled Fab fragments. Possible applications of this method include its use in clinical chemistry and the screening of proteomic or combinatorial libraries

  5. 2-Naphthalenthiol derivatization followed by dispersive liquid-liquid microextraction as an efficient and sensitive method for determination of acrylamide in bread and biscuit samples using high-performance liquid chromatography.

    Science.gov (United States)

    Faraji, Mohammad; Hamdamali, Mohammadrezza; Aryanasab, Fezzeh; Shabanian, Meisam

    2018-07-13

    In this research, an ultrasonic-assisted extraction followed by 2-naphthalenthiol derivatization and dispersive liquid-liquid microextraction of acrylamide (AA) was developed as simple and sensitive sample preparation method for AA in bread and biscuit samples using high performance liquid chromatography. Influence of derivatization and microextraction parameters were evaluated and optimized. Results showed that the derivatization of AA leads to improve its hydrophobicity and chromatographic behavior. Under optimum conditions of derivatization and microextraction, the method yielded a linear calibration curve ranging from 10 to 1000 μg L -1 with a determination coefficient (R 2 ) of 0.9987. Limit of detection (LOD) and limit of quantification (LOQ) were 3.0 and 9.0 μg L -1 , respectively. Intra-day (n = 6) and inter-day (n = 3) precisions based on relative standard deviation percent (RSD%) for extraction and determination of AA at 50 and 500 μg L -1 levels were less than 9.0%. Finally, the performance of proposed method was investigated for determination of AA in some bread and biscuit samples, and satisfactory results were obtained (relative recovery ≥ 90%). Copyright © 2018. Published by Elsevier B.V.

  6. Preconcentration and determination of ceftazidime in real samples using dispersive liquid-liquid microextraction and high-performance liquid chromatography with the aid of experimental design.

    Science.gov (United States)

    Razmi, Rasoul; Shahpari, Behrouz; Pourbasheer, Eslam; Boustanifar, Mohammad Hasan; Azari, Zhila; Ebadi, Amin

    2016-11-01

    A rapid and simple method for the extraction and preconcentration of ceftazidime in aqueous samples has been developed using dispersive liquid-liquid microextraction followed by high-performance liquid chromatography analysis. The extraction parameters, such as the volume of extraction solvent and disperser solvent, salt effect, sample volume, centrifuge rate, centrifuge time, extraction time, and temperature in the dispersive liquid-liquid microextraction process, were studied and optimized with the experimental design methods. Firstly, for the preliminary screening of the parameters the taguchi design was used and then, the fractional factorial design was used for significant factors optimization. At the optimum conditions, the calibration curves for ceftazidime indicated good linearity over the range of 0.001-10 μg/mL with correlation coefficients higher than the 0.98, and the limits of detection were 0.13 and 0.17 ng/mL, for water and urine samples, respectively. The proposed method successfully employed to determine ceftazidime in water and urine samples and good agreement between the experimental data and predictive values has been achieved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Liquid chromatography with mass spectrometry and NMR spectroscopy based discovery of cytotoxic principles from Daphne tangutica Maxim.

    Science.gov (United States)

    Yang, Xinzhou; Huang, Mi; Zheng, Sijian; Ma, Xinhua; Wan, Dingrong; Feng, Yunjiang

    2016-06-01

    An ethyl acetate extract from the barks of the ethnic Chinese medicine Daphne tangutica Maxim. exhibited antihepatocellular carcinoma activity against HepG2 and Hep3B cell lines. By using high-performance liquid chromatography based activity profiling in combination with offline liquid chromatography with mass spectrometry and NMR analysis, we rapidly identified ten major components of the extract, including seven active principles, coumarins (1-4) and biscoumarins (7, 8, 10), along with three inactive flavonoids (5, 6, 9). This study demonstrated that our combined protocol can be used as an important strategy for chemical profiling, dereplication as well as the identification of bioactive compounds from herbal medicines. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Determination of Diclofenac sodium by high-performance liquid chromatography in 0,1 % eyedrops

    International Nuclear Information System (INIS)

    Garcia Penna, Caridad Margarita; Pereda Rodriguez, Diana; Gonzalez Hortezon, Ania; Montes de Oca Porto, Yanet; Cannizares Arencibia, Yanara; Leon Guerrero, Gissel Maria

    2009-01-01

    Diclofenac sodium is a drug prescribed in eye anterior segment inflammation postoperative treatments, preoperative and postoperative cataract meiosis inhibition, symptomatic treatment of non-infectious chronic conjunctivitis, of ocular inflammation, of ocular pain, and of refractory postsurgical photophobia. In present paper we developed and validated an analytical method by high-performance liquid chromatography to quality control, and stability studies of Diclofenac sodium of 1 % eye drops. Method was based on active principle separation through endcapped 1 00RP-8 Lichrospher chromatographic column (5 μ) (250 x 4 mm) using UV detection to 254 nm, thus using a mobile phase including sodium a solution of hydrogen phosphate to a 2.5 pH: methanol in a 34:60 ratio. Calibration curve was plotted during the interval of 60 to 140 % where it was linear with a correlation coefficient equal to 0.9995; statistic test for interception and slope was considered as non-significant. We achieved a recovery rate of 100.25 % during study concentration interval, and Cochran (G) and Student (t) tests were not significant. Variation coefficient in repeating study was equal to 0.39 % for the 6 assayed replica, whereas in average precision analysis Fischer and Student tests were non-significant. Analytical method was linear, precise, specific and exact during the interval of study concentrations. (Author)

  9. Determination of La and Nd by thermal ionization mass spectrometry (TIMS) pre-separated by high performance liquid chromatography (HPLC)

    International Nuclear Information System (INIS)

    Jaison, P.G.; Raut, N.M.; Parab, A.R.; Khodade, P.S.; Govindan, R.; Aggarwal, S.K.

    2003-01-01

    Determination of La and Nd by TIMS is required for accurate determination of burn-up of nuclear fuels. During their thermal ionization mass spectrometric (TIMS) analysis, 138 Ce and 142 Ce show spectroscopic isobaric interferences at 138 La and 142 Nd, respectively. Hence, it is essential to remove Ce from La and Nd for their accurate isotopic composition determination. Reversed phase high performance liquid chromatography (HPLC) is a promising technique for rapid and effective separation

  10. Combination of saponification and dispersive liquid-liquid microextraction for the determination of tocopherols and tocotrienols in cereals by reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Shammugasamy, Balakrishnan; Ramakrishnan, Yogeshini; Ghazali, Hasanah M; Muhammad, Kharidah

    2013-07-26

    A simple sample preparation technique coupled with reversed-phase high-performance liquid chromatography was developed for the determination of tocopherols and tocotrienols in cereals. The sample preparation procedure involved a small-scale hydrolysis of 0.5g cereal sample by saponification, followed by the extraction and concentration of tocopherols and tocotrienols from saponified extract using dispersive liquid-liquid microextraction (DLLME). Parameters affecting the DLLME performance were optimized to achieve the highest extraction efficiency and the performance of the developed DLLME method was evaluated. Good linearity was observed over the range assayed (0.031-4.0μg/mL) with regression coefficients greater than 0.9989 for all tocopherols and tocotrienols. Limits of detection and enrichment factors ranged from 0.01 to 0.11μg/mL and 50 to 73, respectively. Intra- and inter-day precision were lower than 8.9% and the recoveries were around 85.5-116.6% for all tocopherols and tocotrienols. The developed DLLME method was successfully applied to cereals: rice, barley, oat, wheat, corn and millet. This new sample preparation approach represents an inexpensive, rapid, simple and precise sample cleanup and concentration method for the determination of tocopherols and tocotrienols in cereals. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Determination of some organophosphorus pesticides in water and watermelon samples by microextraction prior to high-performance liquid chromatography.

    Science.gov (United States)

    Wang, Chun; Wu, Qiuhua; Wu, Chunxia; Wang, Zhi

    2011-11-01

    A novel method based on simultaneous liquid-liquid microextraction and carbon nanotube reinforced hollow fiber microporous membrane solid-liquid phase microextraction has been developed for the determination of six organophosphorus pesticides, i.e. isocarbophos, phosmet, parathion-methyl, triazophos, fonofos and phoxim, in water and watermelon samples prior to high-performance liquid chromatography (HPLC). Under the optimum conditions, the method shows a good linearity within a range of 1-200 ng/mL for water samples and 5-200 ng/g for watermelon samples, with the correlation coefficients (r) varying from 0.9990 to 0.9997 and 0.9986 to 0.9995, respectively. The limits of detection (LODs) were in the range between 0.1 and 0.3 ng/mL for water samples and between 1.0 and 1.5 ng/g for watermelon samples. The recoveries of the method at spiking levels of 5.0 and 50.0 ng/mL for water samples were between 85.4 and 100.8%, and at spiking levels of 5.0 and 50.0 ng/g for watermelon samples, they were between 82.6 and 92.4%, with the relative standard deviations (RSDs) varying from 4.5-6.9% and 5.2-7.4%, respectively. The results suggested that the developed method represents a simple, low-cost, high analytes preconcentration and excellent sample cleanup procedure for the determination of organophosphorus pesticides in water and watermelon samples. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Speciation of mercury in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography-inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Jia Xiaoyu; Han Yi; Liu Xinli [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science, Changchun 130022 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Duan Taicheng, E-mail: tcduan@ciac.jl.cn [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science, Changchun 130022 (China); Chen Hangting, E-mail: htchen@ciac.jl.cn [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science, Changchun 130022 (China)

    2011-01-15

    The dispersive liquid-liquid microextraction (DLLME) combined with high performance liquid chromatography-inductively coupled plasma mass spectrometry for the speciation of mercury in water samples was described. Firstly methylmercury (MeHg{sup +}) and mercury (Hg{sup 2+}) were complexed with sodium diethyldithiocarbamate, and then the complexes were extracted into carbon tetrachloride by using DLLME. Under the optimized conditions, the enrichment factors of 138 and 350 for MeHg{sup +} and Hg{sup 2+} were obtained from only 5.00 mL sample solution. The detection limits of the analytes (as Hg) were 0.0076 ng mL{sup -1} for MeHg{sup +} and 0.0014 ng mL{sup -1} for Hg{sup 2+}, respectively. The relative standard deviations for ten replicate measurements of 0.5 ng mL{sup -1} MeHg{sup +} and Hg{sup 2+} were 6.9% and 4.4%, respectively. Standard reference material of seawater (GBW(E)080042) was analyzed to verify the accuracy of the method and the results were in good agreement with the certified values. Finally, the developed method was successfully applied for the speciation of mercury in three environmental water samples.

  13. Comparative Study of Continuous Pralidoxime Infusion versus Intermittent Dosing: Application of High-Performance Liquid Chromatography Method on Serum of Organophosphate Poisoned Patients

    Directory of Open Access Journals (Sweden)

    Girish Thunga

    2013-09-01

    How to cite this article: Thunga G, Pandey S, Nair S, Mylapuri R, Vidyasagar S, Kunhikatta V, et al. Comparative Study of Continuous Pralidoxime Infusion versus Intermittent Dosing: Application of High-Performance Liquid Chromatography Method on Serum of Organophosphate Poisoned Patients. Asia Pac J Med Toxicol 2013;2:105-10.

  14. [Simultaneous determination of four compounds in Sanjing Shuanghuanglian Oral Liquid by high performance liquid chromatography-diode array detection-electrochemical detection].

    Science.gov (United States)

    Liu, Lin; Suo, Zhirong; Zheng, Jianbin

    2006-05-01

    Chlorogenic acid, caffeic acid, baicalin and luteolin in Sanjing Shuanghuanglian Oral Liquid were simultaneously detected and identified using a high performance liquid chromatography coupled with diode array detection and electrochemical detection (HPLC-DAD-ECD). The separation was performed on a Zorbax SB-C18 column (150 mm x 4.6 mm i. d., 5.0 microm). The mobile phase consisted of (A) methanol and (B) methanol-water-acetic acid (50: 50: 1, v/v/v) using a linear gradient elution of 2%A-3%A at 0-3 min, 3%A-25%A at 3-15 min, 25%A-80%A at 15-20 min. The flow rate was 0.8 mL/min. The DAD detection was used at 275 nm. The ECD detection was done at 0.7 V. The column thermostat set at 30 degrees C. The limits of detection of the 4 compounds were 1 mg/L for chlorogenic acid, 0.2 mg/L for caffeic acid, 9 mg/L for baicalin, 7 mg/L for luteolin. The average recoveries were between 96.6%-99.6% with relative standard deviations (RSDs) of 2.5%-4.1%. The method is simple, rapid, reproducible and accurate. It can be used for the routine analysis of the four compounds in Shuanghuanglian Oral Liquid.

  15. Application of solvent floatation to separation and determination of triazine herbicides in honey by high-performance liquid chromatography.

    Science.gov (United States)

    Wang, Kun; Jiang, Jia; Lv, Xinping; Zang, Shuang; Tian, Sizhu; Zhang, Hanqi; Yu, Aimin; Zhang, Ziwei; Yu, Yong

    2018-03-01

    Based on the foaming property of the honey, a rapid, simple, and effective method solvent floatation (SF) was developed and firstly applied to the extraction and separation of triazine herbicides in honey. The analytes were determined by high-performance liquid chromatography. Some parameters affecting the extraction efficiencies, such as the type and volume of extraction solvent, type of salt, amount of (NH 4 ) 2 SO 4 , pH value of sample solution, gas flow rate, and floatation time, were investigated and optimized. The limits of detection for analytes are in the range of 0.16-0.56 μg kg -1 . The recoveries and relative standard deviations for determining triazines in five real honey samples are in the range of 78.2-112.9 and 0.2-9.2%, respectively.

  16. Quantification of Fatty Acid Oxidation Products Using On-line High Performance Liquid Chromatography Tandem Mass Spectrometry

    Science.gov (United States)

    Levison, Bruce S.; Zhang, Renliang; Wang, Zeneng; Fu, Xiaoming; DiDonato, Joseph A.; Hazen, Stanley L.

    2013-01-01

    Oxidized fatty acids formed via lipid peroxidation are implicated in pathological processes such as inflammation and atherosclerosis. A number of methods may be used to detect specific oxidized fatty acids containing a single or multiple combinations of epoxide, hydroxyl, ketone and hydroperoxide moieties on varying carbon chain lengths from C8 up to C30. Some of these methods are nonspecific and their use in biological systems is fraught with difficulty. Measures of specific-oxidized fatty acid derivatives help in identifying oxidation pathways in pathological processes. We used liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-MS/MS) as efficient, selective and sensitive methods for identifying and analyzing multiple specific fatty acid peroxidation products in human plasma and other biological matrices. We then distilled the essential components of a number of these analyses to provide an efficient protocol by which fatty acid oxidation products and their parent compounds can be determined. In this protocol, addition of synthetic internal standard to the sample, followed by base hydrolysis at elevated temperature, and liquid-liquid phase sample extraction with lighter than water solvents facilitates isolation of the oxidized fatty acid species. These species can be identified and accurately quantified using stable isotope dilution and multiple reaction monitoring. Use of a coupled multiplexed gradient HPLC system on the front end enables high-throughput chromatography and more efficient use of mass spectrometer time. PMID:23499838

  17. Phytochemical analysis of ethanolic extract of Dichrostachys Cinerea W and Arn leaves by a thin layer chromatography, high performance thin layer chromatography and column chromatography

    OpenAIRE

    M Vijayalakshmi; K Periyanayagam; K Kavitha; K Akilandeshwari

    2013-01-01

    Background: The leaves of Dichrostachys cinerea are used as laxative, diuretic, painkiller. It is also used in the treatment of gonorrhoea, boils, oedema, gout, veneral diseases and nasopharyngeal affections, etc. Materials and Methods: The Phytochemical investigation of ethanolic extract of D. cinerea leaves were performed by standard chemical tests, thin layer chromatography (TLC) by using various solvent systems, and by high performance liquid chromatography (HPTLC). Two compounds were...

  18. High Performance Liquid Chromatography of Some Analgesic Compounds: An Instrumental Analysis Experiment.

    Science.gov (United States)

    Haddad, Paul; And Others

    1983-01-01

    Background information, procedures, and results are provided for an experiment demonstrating techniques of solvent selection, gradient elution, pH control, and ion-pairing in the analysis of an analgesic mixture using reversed-phase liquid chromatography on an octadecylsilane column. Although developed using sophisticated/expensive equipment, less…

  19. Separation properties of the MIL-125(Ti) Metal-Organic Framework in high-performance liquid chromatography revealing cis/trans selectivity.

    Science.gov (United States)

    Van der Perre, Stijn; Liekens, Anuschka; Bueken, Bart; De Vos, Dirk E; Baron, Gino V; Denayer, Joeri F M

    2016-10-21

    Monodisperse MIL-125(Ti) Metal-Organic Framework crystals were synthesized and studied as stationary phase in high performance liquid chromatography (HPLC). Different pure compounds and model mixtures (including stereoisomer mixtures) were injected from which chromatographic parameters, including selectivities and resolution factors, were determined to evaluate the adsorption properties and separation performance of MIL-125(Ti) in liquid phase. The MIL-125(Ti) framework displayed a trans selectivity for cis/trans difunctionalized cyclohexane molecules with high selectivity and resolution for 1,3-dimethylcyclohexane and 4-ethylcyclohexanol. The slurry-packed column was further characterized via van Deemter analysis. Fitting of the van Deemter equation through the experimental points allowed to define the contributions of the different processes to plate height with a significant proportion of the A-term, reflecting the importance of a good crystal packing. Although high in comparison to commercial HPLC stationary phases, a very good plate height of around 50μm was found. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Separation and quantitation of polyethylene glycols 400 and 3350 from human urine by high-performance liquid chromatography.

    Science.gov (United States)

    Ryan, C M; Yarmush, M L; Tompkins, R G

    1992-04-01

    Polyethylene glycol 3350 (PEG 3350) is useful as an orally administered probe to measure in vivo intestinal permeability to macromolecules. Previous methods to detect polyethylene glycol (PEG) excreted in the urine have been hampered by inherent inaccuracies associated with liquid-liquid extraction and turbidimetric analysis. For accurate quantitation by previous methods, radioactive labels were required. This paper describes a method to separate and quantitate PEG 3350 and PEG 400 in human urine that is independent of radioactive labels and is accurate in clinical practice. The method uses sized regenerated cellulose membranes and mixed ion-exchange resin for sample preparation and high-performance liquid chromatography with refractive index detection for analysis. The 24-h excretion for normal individuals after an oral dose of 40 g of PEG 3350 and 5 g of PEG 400 was 0.12 +/- 0.04% of the original dose of PEG 3350 and 26.3 +/- 5.1% of the original dose of PEG 400.

  1. Characterisation of chemical components for identifying historical Chinese textile dyes by ultra high performance liquid chromatography – photodiode array – electrospray ionisation mass spectrometer

    NARCIS (Netherlands)

    Han, J.; Wanrooij, J.; van Bommel, M.; Quye, A.

    2017-01-01

    This research makes the first attempt to apply Ultra High Performance Liquid Chromatography (UHPLC) coupled to both Photodiode Array detection (PDA) and Electrospray Ionisation Mass Spectrometer (ESI–MS) to the chemical characterisation of common textile dyes in ancient China. Three different

  2. Validation of a high performance liquid chromatography analysis for the determination of noradrenaline and adrenaline in human urine with an on-line sample purification

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Kristiansen, J; Nielsen, J L

    1999-01-01

    A high performance liquid chromatography (HPLC) method with fluorescence detection including an on-line purification was established for determination of catecholamines in human urine. The method was evaluated using samples of pooled urine spiked with catecholamines and validated for measurements...

  3. The art and science of forming packed analytical high-performance liquid chromatography columns.

    Science.gov (United States)

    Kirkland, J J; Destefano, J J

    2006-09-08

    Columns of packed particles still are the most popular devices for high-performance liquid chromatography (HPLC) separations because of their great utility, excellent performance and wide variety. However, the forming of packed beds for efficient, stable columns traditionally has been an art where the basics of how to form optimum beds generally was not well understood. The recent development of monolith rods was introduced in part to overcome the difficulty of producing stable beds of packing particles. However, these materials are less versatile than packed particle columns. Technology developments in recent years have produced a better understanding among those skilled in the practice of how to form optimized packed beds, and this has led to widely available, high-quality commercial columns. This presentation discusses the developments that led to the present state of column packing technology. Important steps in the packing of efficient, stable beds are described. The key step of selecting the best solvent for the slurry packing method is emphasized. Factors affecting the mechanical stability of packed columns also are discussed. The early art of packing columns now has evolved into a more scientific approach that allows the packing of good columns with a minimum of effort and time.

  4. Characterization of polyoxyethylene tallow amine surfactants in technical mixtures and glyphosate formulations using ultra-high performance liquid chromatography and triple quadrupole mass spectrometry

    Science.gov (United States)

    Tush, Daniel; Loftin, Keith A.; Meyer, Michael T.

    2013-01-01

    Little is known about the occurrence, fate, and effects of the ancillary additives in pesticide formulations. Polyoxyethylene tallow amine (POEA) is a non-ionic surfactant used in many glyphosate formulations, a widely applied herbicide both in agricultural and urban environments. POEA has not been previously well characterized, but has been shown to be toxic to various aquatic organisms. Characterization of technical mixtures using ultra-high performance liquid chromatography (UHPLC) and mass spectrometry shows POEA is a complex combination of homologs of different aliphatic moieties and ranges of ethoxylate units. Tandem mass spectrometry experiments indicate that POEA homologs generate no product ions readily suitable for quantitative analysis due to poor sensitivity. A comparison of multiple high performance liquid chromatography (HPLC) and UHPLC analytical columns indicates that the stationary phase is more important in column selection than other parameters for the separation of POEA. Analysis of several agricultural and household glyphosate formulations confirms that POEA is a common ingredient but ethoxylate distributions among formulations vary.

  5. Method transfer from high-pressure liquid chromatography to ultra-high-pressure liquid chromatography. II. Temperature and pressure effects.

    Science.gov (United States)

    Åsberg, Dennis; Samuelsson, Jörgen; Leśko, Marek; Cavazzini, Alberto; Kaczmarski, Krzysztof; Fornstedt, Torgny

    2015-07-03

    The importance of the generated temperature and pressure gradients in ultra-high-pressure liquid chromatography (UHPLC) are investigated and compared to high-pressure liquid chromatography (HPLC). The drug Omeprazole, together with three other model compounds (with different chemical characteristics, namely uncharged, positively and negatively charged) were used. Calculations of the complete temperature profile in the column at UHPLC conditions showed, in our experiments, a temperature difference between the inlet and outlet of 16 °C and a difference of 2 °C between the column center and the wall. Through van't Hoff plots, this information was used to single out the decrease in retention factor (k) solely due to the temperature gradient. The uncharged solute was least affected by temperature with a decrease in k of about 5% while for charged solutes the effect was more pronounced, with k decreases up to 14%. A pressure increase of 500 bar gave roughly 5% increase in k for the uncharged solute, while omeprazole and the other two charged solutes gave about 25, 20 and 15% increases in k, respectively. The stochastic model of chromatography was applied to estimate the dependence of the average number of adsorption/desorption events (n) and the average time spent by a molecule in the stationary phase (τs) on temperature and pressure on peak shape for the tailing, basic solute. Increasing the temperature yielded an increase in n and decrease in τs which resulted in less skew at high temperatures. With increasing pressure, the stochastic modeling gave interesting results for the basic solute showing that the skew of the peak increased with pressure. The conclusion is that pressure effects are more pronounced for both retention and peak shape than the temperature effects for the polar or charged compounds in our study. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Protective properties of wine products and the role of high performance liquid chromatography in the study of these properties

    International Nuclear Information System (INIS)

    Ulyanova, E V; Larionov, O G; Revina, A A; Andrievskaya, D V; Urusova, L M; Fenin, A A

    2013-01-01

    Data on the biologically active substances present in wines and wine products, the methods of their determination, and changes under chemical, radiation and other types of action are generalized. The role of high performance liquid chromatography in the studies of the protective properties of wines is demonstrated. Particular attention is devoted to problems of counterfeiting of wine products and the possibility to reveal it by using amperometric determination of the antioxidant activity. The bibliography includes 117 references

  7. Improved separation of conjugated fatty acid methyl esters by silver ion-high-performance liquid chromatography.

    Science.gov (United States)

    Sehat, N; Rickert, R; Mossoba, M M; Kramer, J K; Yurawecz, M P; Roach, J A; Adlof, R O; Morehouse, K M; Fritsche, J; Eulitz, K D; Steinhart, H; Ku, Y

    1999-04-01

    Operating from one to six silver ion-high-performance liquid chromatography (Ag+-HPLC) columns in series progressively improved the resolution of the methyl esters of conjugated linoleic acid (CLA) isomeric mixtures from natural and commercial products. In natural products, the 8 trans, 10 cis-octadecadienoic (18:2) acid was resolved from the more abundant 7 trans, 9 cis-18:2, and the 10 trans, 12 cis-18:2 was separated from the major 9 cis, 11 trans-18:2 peak. In addition, both 11 trans, 13 cis-18:2 and 11 cis, 13 trans-18:2 isomers were found in natural products and were separated; the presence of the latter, 11 cis, 13 trans-18:2, was established in commercial CLA preparations. Three Ag+-HPLC columns in series appeared to be the best compromise to obtain satisfactory resolution of most CLA isomers found in natural products. A single Ag+-HPLC column in series with one of several normal-phase columns did not improve the resolution of CLA isomers as compared to that of the former alone. The 20:2 conjugated fatty acid isomers 11 cis, 13 trans-20:2 and 12 trans, 14 cis-20:2, which were synthesized by alkali isomerization from 11 cis, 14 cis-20:2, eluted in the same region of the Ag+-HPLC chromatogram just before the corresponding geometric CLA isomers. Therefore, CLA isomers will require isolation based on chain length prior to Ag+-HPLC separation. The positions of conjugated double bonds in 20:2 and 18:2 isomers were established by gas chromatography-electron ionization mass spectrometry as their 4,4-dimethyloxazoline derivatives. The double-bond geometry was determined by gas chromatography-direct deposition-Fourier transform infrared spectroscopy and by the Ag+-HPLC relative elution order.

  8. Rapid determination of parabens in seafood sauces by high-performance liquid chromatography: A practical comparison of core-shell particles and sub-2 μm fully porous particles.

    Science.gov (United States)

    Ye, Jing; Cao, Xiaoji; Cheng, Zhuo; Qin, Ye; Lu, Yanbin

    2015-12-01

    In this work, the chromatographic performance of superficially porous particles (Halo core-shell C18 column, 50 mm × 2.1 mm, 2.7 μm) was compared with that of sub-2 μm fully porous particles (Acquity BEH C18 , 50 mm × 2.1 mm, 1.7 μm). Four parabens, methylparaben, ethylparaben, propylparaben, and butylparaben, were used as representative compounds for calculating the plate heights in a wide flow rate range and analyzed on the basis of the Van Deemter and Knox equations. Theoretical Poppe plots were constructed for each column to compare their kinetic performance. Both phases gave similar minimum plate heights when using nonreduced coordinates. Meanwhile, the flat C-term of the core-shell column provided the possibilities for applying high flow rates without significant loss in efficiency. The low backpressure of core-shell particles allowed this kind of column, especially compatible with conventional high-performance liquid chromatography systems. Based on these factors, a simple high-performance liquid chromatography method was established and validated for the determination of parabens in various seafood sauces using the Halo core-shell C18 column for separation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Comparison of High Performance Liquid Chromatography with Fluorescence Detector and with Tandem Mass Spectrometry methods for detection and quantification of Ochratoxin A in green and roasted coffee beans

    Directory of Open Access Journals (Sweden)

    Raquel Duarte da Costa Cunha Bandeira

    2013-12-01

    Full Text Available Two analytical methods for the determination and confirmation of ochratoxin A (OTA in green and roasted coffee samples were compared. Sample extraction and clean-up were based on liquid-liquid phase extraction and immunoaffinity column. The detection of OTA was carried out with the high performance liquid chromatography (HPLC combined either with fluorescence detection (FLD, or positive electrospray ionization (ESI+ coupled with tandem mass spectrometry (MS-MS. The results obtained with the LC-ESI-MS/MS were specific and more sensitive, with the advantages in terms of unambiguous analyte identification, when compared with the HPLC-FLD.

  10. Determination of phenolic acids and flavonoids in raw propolis by silica-supported ionic liquid-based matrix solid phase dispersion extraction high performance liquid chromatography-diode array detection.

    Science.gov (United States)

    Wang, Zhibing; Sun, Rui; Wang, Yuanpeng; Li, Na; Lei, Lei; Yang, Xiao; Yu, Aimin; Qiu, Fangping; Zhang, Hanqi

    2014-10-15

    The silica-supported ionic liquid (S-SIL) was prepared by impregnation and used as the dispersion adsorbent of matrix solid phase dispersion (MSPD) for the simultaneous extraction of eight phenolic acids and flavonoids, including caffeic acid, ferulic acid, morin, luteolin, quercetin, apigenin, chrysin, and kaempferide in raw propolis. High performance liquid chromatography with a Zorbax SB-C18 column (150mm×4.6mm, 3.5μm) was used for separation of the analytes. The mobile phase consisted of 0.2% phosphoric acid aqueous solution and acetonitrile and the flow rate of the mobile phase was 0.5mL/min. The experimental conditions for silica-supported ionic liquid-based matrix solid phase dispersion (S-SIL-based MSPD) were optimized. S-SIL containing 10% [C6MIM]Cl was used as dispersant, 20mL of n-hexane as washing solvent and 15mL of methanol as elution solvent. The ratio of S-SIL to sample was selected to be 4:1. The standard curves showed good linear relationship (r>0.9995). The limits of detection and quantification were in the range of 5.8-22.2ngmL(-1) and 19.2-74.0ngmL(-1), respectively. The relative standard deviations (RSDs) of intra-day and inter-day determination were lower than 8.80% and 11.19%, respectively. The recoveries were between 65.51% and 92.32% with RSDs lower than 8.95%. Compared with ultrasound-assisted extraction (UAE) and soxhlet extraction, the present method consumed less sample, organic solvent, and extraction time, although the extraction yields obtained by S-SIL-based MSPD are slightly lower than those obtained by UAE. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Application and comparison of high-speed countercurrent chromatography and high performance liquid chromatography in preparative enantioseparation of α-substitution mandelic acids.

    Science.gov (United States)

    Tong, Shengqiang; Zhang, Hu; Shen, Mangmang; Ito, Yoichiro; Yan, Jizhong

    2015-04-01

    Preparative enantioseparations of α-cyclopentylmandelic acid and α-methylmandelic acid by high-speed countercurrent chromatography (HSCCC) and high performance liquid chromatography (HPLC) were compared using hydroxypropy-β-cyclodextrin (HP-β-CD) and sulfobutyl ether-β-cyclodextrin (SBE-β-CD) as the chiral mobile phase additives. In preparative HPLC the enantioseparation was achieved on the ODS C 18 reverse phase column with the mobile phase composed of a mixture of acetonitrile and 0.10 mol L -1 phosphate buffer at pH 2.68 containing 20 mmol L -1 HP-β-CD for α-cyclopentylmandelic acid and 20 mmol L -1 SBE-β-CD for α-methylmandelic acid. The maximum sample size for α-cyclopentylmandelic acid and α-methylmandelic acid was only about 10 mg and 5 mg, respectively. In preparative HSCCC the enantioseparations of these two racemates were performed with the two-phase solvent system composed of n -hexane-methyl tert. -butyl ether-0.1 molL -1 phosphate buffer solution at pH 2.67 containing 0.1 mol L -1 HP-β-CD for α-cyclopentylmandelic acid (8.5:1.5:10, v/v/v) and 0.1 mol L -1 SBE-β-CD for α-methylmandelic acid (3:7:10, v/v/v). Under the optimum separation conditions, total 250 mg of racemic α-cyclopentylmandelic acid could be completely enantioseparated by HSCCC with HP-β-CD as a chiral mobile phase additive in a single run, yielding 105-110 mg of enantiomers with 95-98% purity and 85-90% recovery. But, no complete enantioseparation of α-methylmandelic acid was achieved by preparative HSCCC with either of the chiral selectors due to their limited enantioselectivity. In this paper preparative enantioseparation by HSCCC and HPLC was compared from various aspects.

  12. [Determination of amitrole in agricultural products by high performance liquid chromatography-tandem mass spectrometry].

    Science.gov (United States)

    Li, Li; Fu, Jian; Gao, Hongliang; Ren, Haitao; Lou, Xishan; Guan, Lihui

    2010-03-01

    A high performance liquid chromatography-tandem mass spectrometry method (HPLC-MS/MS) was developed for the analysis of amitrole residues in agricultural products. The samples were extracted by 25% acetone for wheat, fish, pork and liver samples, 1% acetic acid-25% acetone for maize and peanut samples, 1% acetic acid solution for honeysuckle, the powder of ginger, the powder of bunge prickly ash and tea leaves samples, 1% acetic acid solution-dichloromethane for apple, pineapple, spinach, carrot, perilla leaves samples, respectively, followed by liquid-liquid extraction with dichloromethane. The samples were then cleaned up by PCX or Envi-Carb solid-phase extraction cartridge. The amitrole was determined and confirmed by HPLC-MS/MS. The results showed a linear relationship in the range of 0.005 -0.1 mg/kg for amitrole. The correlation coefficient was 0.999 7. The average recoveries of amitrole in wheat, maize, peanut, pineapple, apple, carrot, spinach, pork, the powder of ginger, the powder of bunge prickly ash, perilla, liver, fish, honeysuckle and tea were 67.5% - 98.1%. The relative standard deviations (RSDs) were 1.0% - 9.8%. The limits of quantitation were 10 microg/kg for wheat, maize, peanut, pineapple, apple, carrot, spinach, pork, perilla, liver, fish, honeysuckle and 20 microg/kg for the powder of bunge prickly ash, the powder of ginger and tea, respectively. The method is simple, sensitive and accurate.

  13. Reduction of silanophilic interactions in liquid chromatography with the use of ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    MarszaII, MichaI Piotr [Department of Biopharmaceutics and Pharmacodynamics, Medical University of Gdansk, Gen. J. Hallera 107, 80-416 Gdansk (Poland); Baczek, Tomasz [Department of Biopharmaceutics and Pharmacodynamics, Medical University of Gdansk, Gen. J. Hallera 107, 80-416 Gdansk (Poland); Kaliszan, Roman [Department of Biopharmaceutics and Pharmacodynamics, Medical University of Gdansk, Gen. J. Hallera 107, 80-416 Gdansk (Poland)]. E-mail: roman.kaliszan@amg.gda.pl

    2005-08-22

    A suppression of silanophilic interactions by the selected ionic liquids added to the mobile phase in thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) is reported. Acetonitrile was used as the eluent, alone or with various concentrations of water and phosphoric buffer pH 3. Selectivity of the normal (NP) and the reversed (RP) stationary phase material was examined using a series of proton-acceptor basic drugs analytes. The ionic liquids studied appeared to significantly affect analyte retention in NP-TLC, RP-TLC and RP-HPLC systems tested. Consequently, the increased separation selectivity was attained. Due to ionic liquid additives to eluent even analytes could be chromatographed, which were not eluted from the silica-based stationary phase materials with 100% of acetonitrile in the mobile phase. Addition of ionic liquid already in very small concentration (0.5%, v/v) could reduce the amount of acetonitrile used during the optimization of basic analytes separations in TLC and HPLC systems. Moreover, the influence of temperature on the separation of basic analytes was demonstrated and considered in practical HPLC method development.

  14. Reduction of silanophilic interactions in liquid chromatography with the use of ionic liquids

    International Nuclear Information System (INIS)

    MarszaII, MichaI Piotr; Baczek, Tomasz; Kaliszan, Roman

    2005-01-01

    A suppression of silanophilic interactions by the selected ionic liquids added to the mobile phase in thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) is reported. Acetonitrile was used as the eluent, alone or with various concentrations of water and phosphoric buffer pH 3. Selectivity of the normal (NP) and the reversed (RP) stationary phase material was examined using a series of proton-acceptor basic drugs analytes. The ionic liquids studied appeared to significantly affect analyte retention in NP-TLC, RP-TLC and RP-HPLC systems tested. Consequently, the increased separation selectivity was attained. Due to ionic liquid additives to eluent even analytes could be chromatographed, which were not eluted from the silica-based stationary phase materials with 100% of acetonitrile in the mobile phase. Addition of ionic liquid already in very small concentration (0.5%, v/v) could reduce the amount of acetonitrile used during the optimization of basic analytes separations in TLC and HPLC systems. Moreover, the influence of temperature on the separation of basic analytes was demonstrated and considered in practical HPLC method development

  15. Utilization of high performance liquid chromatography coupled to tandem mass spectrometry for characterization of 8-O-methylbostrycoidin production by species of the fungus Fusarium

    Science.gov (United States)

    The pigment, 8-O-methylbostrycoidin is a polyketide metabolite produced by multiple species of the fungus Fusarium that infects plant crops, including maize. A technique was developed for the analysis of 8-O-methylbostrycoidin by high performance liquid chromatography coupled to electrospray ionizat...

  16. Comparative oxidation state specific analysis of arsenic species by high-performance liquid chromatography-inductively coupled-mass spectrometry and hydride generation-cryotrapping-atomic absorption spectrometry

    Science.gov (United States)

    The formation of methylarsonous acid (MAsIII) and dimethylarsinous acid (DMAsIII) in the course of inorganic arsenic (iAs) metabolism plays an important role in the adverse effects of chronic exposure to iAs. High-performance liquid chromatography-inductively coupled plasma-mass ...

  17. High-performance liquid chromatography on-line coupled to high-field NMR and mass spectrometry for structure elucidation of constituents of Hypericum perforatum L

    DEFF Research Database (Denmark)

    Hansen, S. H.; Jensen, A. G.; Cornett, Claus

    1999-01-01

    The on-line separation and structure elucidation of naphthodianthrones, flavonoids, and other constituents of an extract from Hypericum perforatum L, using high performance liquid chromatography (HPLC) coupled on-line with ultraviolet-visible, nuclear magnetic resonance (NMR), and mass spectrometry...... (MS) is described. A conventional reversed-phase HPLC system using ammonium acetate as the buffer substance in the eluent tvas used, and proton NMR spectra were obtained on a 500 MHz NMR instrument. The MS and MS/MS analyses were performed using negative electrospray ionization, In the present study...

  18. Determination of aristolochic acids by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Wang, Yinan; Chan, Wan

    2014-06-25

    Nephrotoxic and carcinogenic aristolochic acids (AAs) are naturally occurring nitrophenanthrene carboxylic acids in the herbal genus Aristolochia. The misuse of AA-containing herbs in preparing slimming drugs has caused hundred of cases of kidney disease in Belgium women in a slimming regime in the early 1990s. Accumulating evidence also suggested that prolong dietary intake of AA-contaminated food is one of the major causes to the Balkan endemic nephropathy that was first observed in the late 1950s. Therefore, analytical methods of high sensitivity are extremely important for safeguarding human exposure to AA-containing herbal medicines, herbal remedies, and food composites. In this paper, we describe the development of a new high-performance liquid chromatography coupled fluorescence detector (HPLC-FLD) method for the sensitive determination of AAs. The method makes use of a novel cysteine-induced denitration reaction that "turns on" the fluorescence of AAs for fluorometric detections. Our results showed that the combination of cysteine-induced denitration and HPLC-FLD analysis allows for sensitive quantification of AA-I and AA-II at detection limits of 27.1 and 25.4 ng/g, respectively. The method was validated and has been successfully applied in quantifying AAs in Chinese herbal medicines.

  19. Preparation and high-performance liquid chromatography of 3'-phosphoadenosine-5'-phospho[35S]sulfate with a predetermined specific activity

    International Nuclear Information System (INIS)

    Delfert, D.M.; Conrad, H.E.

    1985-01-01

    3'-Phosphoadenosine-5'-phospho[35S]sulfate (PAP 35 S) was prepared by incubating ATP and carrier-free H 2 ( 35 )SO 4 with a 100,000g supernatant fraction prepared from chick embryo chondrocytes. The product was partially purified by paper electrophoresis and mixed with unlabeled PAPS to give a solution of PAP 35 S with a specific activity and a concentration approximating those required for the desired metabolic studies. The product was analyzed by high-performance liquid chromatography on an anion-exchange column to determine the proportion of the 35 SO 4 cpm and A260 material found in the PAPS and other contaminating nucleotides. The PAP 35 S was purified further by preparative high-performance liquid chromatography. The exact specific activity of the PAP 35 S was then determined by using this PAP 35 S preparation as the SO 4 donor in a sulfotransferase reaction using a microsomal preparation from the chick embryo chondrocytes as the enzyme and an 3 H-labeled oligosaccharide as the SO 4 acceptor. The sulfated oligosaccharide was then isolated and the number of 3 H and 35 SO 4 counts per minute in this product were used to calculate the specific activity of the donor. The features of this generally useful approach for preparing PAP 35 S of any desired specific activity and concentration are discussed

  20. Study of Separation and Identification of the Active Ingredients in Gardenia jasminoides Ellis Based on a Two-Dimensional Liquid Chromatography by Coupling Reversed Phase Liquid Chromatography and Hydrophilic Interaction Liquid Chromatography.

    Science.gov (United States)

    Zhou, Xuan; Chen, Cen; Ye, Xiaolan; Song, Fenyun; Fan, Guorong; Wu, Fuhai

    2017-01-01

    In this paper, by coupling reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC), a two-dimensional liquid chromatography system was developed for separation and identification of the active ingredients in Gardenia jasminoides Ellis (GJE). By applying the semi-preparative C18 column as the first dimension and the core-shell column as the second dimension, a total of 896 peaks of GJE were separated. Among the 896 peaks, 16 active ingredients including geniposide, gardenoside, gardoside, etc. were identified by mass spectrometry analysis. The results indicated that the proposed two-dimensional RPLC/HILIC system was an effective method for the analysis of GJE and might hold a high potential to become a useful tool for analysis of other complex mixtures. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Purification Efficacy of Synthetic Cannabinoid Conjugates Using High-Pressure Liquid Chromatography

    Science.gov (United States)

    conducted using high-pressure liquid chromatography and gradient screens to determine the most effective means of purifying the SC:dark quencher conjugates...to obtain the highest yields and purity. The purity was verified using liquid chromatographycoupled mass spectroscopy and nuclear magnetic resonance.

  2. Simultaneous detection of six urinary pteridines and creatinine by high-performance liquid chromatography-tandem mass spectrometry for clinical breast cancer detection.

    Science.gov (United States)

    Burton, Casey; Shi, Honglan; Ma, Yinfa

    2013-11-19

    Recent preliminary studies have implicated urinary pteridines as candidate biomarkers in a growing number of malignancies including breast cancer. While the developments of capillary electrophoresis-laser induced fluorescence (CE-LIF), high performance liquid chromatography (HPLC), and liquid chromatography-mass spectroscopy (LC-MS) pteridine urinalyses among others have helped to enable these findings, limitations including poor pteridine specificity, asynchronous or nonexistent renal dilution normalization, and a lack of information regarding adduct formation in mass spectrometry techniques utilizing electrospray ionization (ESI) have prevented application of these techniques to a larger clinical setting. In this study, a simple, rapid, specific, and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and optimized for simultaneous detection of six pteridines previously implicated in breast cancer and creatinine as a renal dilution factor in urine. In addition, this study reports cationic adduct formation of urinary pteridines under ESI-positive ionization for the first time. This newly developed technique separates and detects the following six urinary pteridines: 6-biopterin, 6-hydroxymethylpterin, d-neopterin, pterin, isoxanthopterin, and xanthopterin, as well as creatinine. The method detection limit for the pteridines is between 0.025 and 0.5 μg/L, and for creatinine, it is 0.15 μg/L. The method was also validated by spiked recoveries (81-105%), reproducibility (RSD: 1-6%), and application to 25 real urine samples from breast cancer positive and negative samples through a double-blind study. The proposed technique was finally compared directly with a previously reported CE-LIF technique, concluding that additional or alternative renal dilution factors are needed for proper investigation of urinary pteridines as breast cancer biomarkers.

  3. Applications of plasma spectrometry and high performance liquid chromatography in environmental and food science

    International Nuclear Information System (INIS)

    Iordache, Andreea-Maria; Biraruti, Elisabeta-Irina; Ionete, Roxana-Elena

    2008-01-01

    Full text: Plasma spectrometry has many applications in food science in analysis of a wide range of samples in the food chain. Food science in the broadest sense can be extended to include soil chemistry, plant uptake and, at the other end of the food chain, studies into the metabolic fate of particular elements or elemental species when the foods are consumed by humans or animals. Inductively Coupled Plasma Mass Spectrometry allows multi-element measurements of most elements in the periodic table. A very sensitive analytical technique for trace analysis of samples can be performed by inductively plasma mass spectrometer with quadrupolar detector using ultrasonic nebulization. High Performance Liquid Chromatography (HPLC) is an analytical technique for the separation and determination of organic and inorganic solutes in any samples especially biological, pharmaceutical, food, environmental. The present paper emphasizes that the future tendencies HPLC-ICP-MS is often the preferred analytical technique for these applications due to the simplicity of the coupling between the HPLC and ICP-MS Varian 820 using ultrasonic nebulization, potential for on-line separations with high species specificity and the capability for optimum limits of detection without the necessity of using complex hydride generation mechanisms. (authors)

  4. Food safety evaluation: Detection and confirmation of chloramphenicol in milk by high performance liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    Nicolich, Rebecca S.; Werneck-Barroso, Eduardo; Marques, Marlice A. Sipoli

    2006-01-01

    A simple and rapid procedure for extraction of chloramphenicol (CAP) in milk and analysis by high-performance liquid chromatography coupled with quadrupole mass spectrometry in tandem was developed. The method consisted of one step of liquid-liquid extraction using ethyl acetate and acidified water (10 mmol L -1 formic acid) and HPLC-MS/MS detection. CAP-D5 was used as internal standard. The method was validated according to Commission Decision 2002/657/EC. The calibration curves were linear, with typical r 2 values higher than 0.98. Absolute recovery of CAP from milk proved to be more than 95%, however CAP-D5 absolute recovery was 75%. The method was accurate and reproducible, being successfully applied to the monitoring of CAP in milk samples obtained from the Brazilian market. Decision limit (CCα) was 0.05 ng mL -1 and detection capability (CCβ) was 0.09 ng mL -1

  5. Arsenic speciation by liquid chromatography coupled with ionspray tandem mass spectrometry

    DEFF Research Database (Denmark)

    Corr, J. J.; Larsen, Erik Huusfeldt

    1996-01-01

    Ionspray mass spectrometry, a well established organic analysis technique, has been coupled to high-performance liquid chromatography for speciation of organic arsenic compounds, The ionspray source and differentially pumped interface of the mass spectrometer were operated in dual modes...... fragmentation patterns showing molecular dissociation through an expected common product ion were obtained for the four arsenosugars, Molecular mode detection was utilized for qualitative verification of speciation analysis by high-performance liquid chromatography coupled to inductively coupled plasma mass...

  6. Incidence of Neonatal Hyperphenylalaninemia Based on High-performance Liquid Chromatography Confirmatory Technique in Mazandaran Province, Northern Iran (2007–2015

    Directory of Open Access Journals (Sweden)

    Ali Abbaskhanian

    2017-01-01

    Full Text Available Background: Classic phenylketonuria (PKU is a metabolic disorder. The purpose of this study was to assess epidemiological factors of PKU phenotypes in a neonatal screening program for Mazandaran, Iran. Methods: In this descriptive-retrospective study from 2007 to 2015, neonates PKU level was conducted by phenylalanine level based on a biochemical technique by ELISA and then by confirmatory methods high performance liquid chromatography. Results: Of the 407,244 screened newborns (48.7% girls and 51.3% boys, 14 girls and 13 boys were diagnosed definitely from 465 suspicious cases of PKU. The incidence of PKU was 0.66 in 10,000, which was noted in different severity (severe PKU - 1:67,874, mild PKU - 1:45,249, and HPA - 1:33,937. In addition, we did not detect any cases of nonclassic PKU. Conclusions: Although the consanguineous marriage pattern is a major cause of hyperphenylalaninemia (HPA particularly in Iranian, there was no significant difference between groups in this study. Now, screening should be executed for all of the family that they have the familial history of PKU in Iran. According to varies actual of prevalence and incidence rate of PKU reported a real patient and taking PKU with mild PKU and HPA, it is recommended, the will provide the PKU reports based on the severity of the disease.

  7. Incidence of Neonatal Hyperphenylalaninemia Based on High-performance Liquid Chromatography Confirmatory Technique in Mazandaran Province, Northern Iran (2007–2015)

    Science.gov (United States)

    Abbaskhanian, Ali; Zamanfar, Daniel; Afshar, Parvaneh; Asadpoor, Einollah; Rouhanizadeh, Hamed; Jafarnia, Ali; Shokzadeh, Mohammad

    2017-01-01

    Background: Classic phenylketonuria (PKU) is a metabolic disorder. The purpose of this study was to assess epidemiological factors of PKU phenotypes in a neonatal screening program for Mazandaran, Iran. Methods: In this descriptive-retrospective study from 2007 to 2015, neonates PKU level was conducted by phenylalanine level based on a biochemical technique by ELISA and then by confirmatory methods high performance liquid chromatography. Results: Of the 407,244 screened newborns (48.7% girls and 51.3% boys), 14 girls and 13 boys were diagnosed definitely from 465 suspicious cases of PKU. The incidence of PKU was 0.66 in 10,000, which was noted in different severity (severe PKU - 1:67,874, mild PKU - 1:45,249, and HPA - 1:33,937). In addition, we did not detect any cases of nonclassic PKU. Conclusions: Although the consanguineous marriage pattern is a major cause of hyperphenylalaninemia (HPA) particularly in Iranian, there was no significant difference between groups in this study. Now, screening should be executed for all of the family that they have the familial history of PKU in Iran. According to varies actual of prevalence and incidence rate of PKU reported a real patient and taking PKU with mild PKU and HPA, it is recommended, the will provide the PKU reports based on the severity of the disease. PMID:29184644

  8. Application of ionic liquids in liquid chromatography and electrodriven separation.

    Science.gov (United States)

    Huang, Yi; Yao, Shun; Song, Hang

    2013-08-01

    Ionic liquids (ILs) are salts in the liquid state at ambient temperature, which are nonvolatile, nonflammable with high thermal stability and dissolve easily for a wide range of inorganic and organic materials. As a kind of potential green solvent, they show high efficiency and selectivity in the field of separation research, especially in instrumental analysis. Thus far, ILs have been successfully applied by many related researchers in high-performance liquid chromatography and capillary electrophoresis as chromatographic stationary phases, mobile phase additives or electroosmotic flow modifiers. This paper provides a detailed review of these applications in the study of natural products, foods, drugs and other fine chemicals. Furthermore, the prospects of ILs in liquid chromatographic and electrodriven techniques are discussed.

  9. Cation-exchange high-performance liquid chromatography for variant hemoglobins and HbF/A2: What must hematopathologists know about methodology?

    OpenAIRE

    Sharma, Prashant; Das, Reena

    2016-01-01

    Cation-exchange high-performance liquid chromatography (CE-HPLC) is a widely used laboratory test to detect variant hemoglobins as well as quantify hemoglobins F and A2 for the diagnosis of thalassemia syndromes. It’s versatility, speed, reproducibility and convenience have made CE-HPLC the method of choice to initially screen for hemoglobin disorders. Despite its popularity, several methodological aspects of the technology remain obscure to pathologists and this may have consequences in spec...

  10. Study of high performance liquid chromatography fingerprint for traditional chinese medicine yigongningxue oral liquid

    International Nuclear Information System (INIS)

    Feng, C.; Ruan, J.L.

    2010-01-01

    A simple, reliable and accurate fingerprinting method has been developed for quality control of YiGongNingXue oral liquid. The separation was done by reverse phase chromatography using Zorbax eclipse XDB C/sub 18/ column (250mmx4.6mmi. d. with 5.0 micro m particle size) and detection at 246nm. Methanol (5-95 % in 70 min)-buffer solution (water-phosphorica cid, pH 3.0, 95-0 percent in 70 min) as mobile phase for linear gradient elution. The flow rate was 1.0 mLmin/sup 1/ and the column temperature was at 25 deg. C. The similarity of 20 batches of YGNX oral liquid was more than 90 %. Also 15 common peaks of chromatogram have been detected, ten of them were identified by comparing fingerprint chromatogram with reference substances The HPLC fingerprint can be used to control the quality of YiGongNingXue oral liquid. (author)

  11. Molecular differences between deuterated and protonated polystyrenes using reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Kayillo, Sindy; Gray, Michael J; Shalliker, R Andrew; Dennis, Gary R

    2005-05-06

    Isotopic substitution is a technique used to highlight particular bonds within a molecule for kinetic, spectroscopic and structure analysis. It is presumed that although some properties such as stretching frequencies will not be the same for substituted analogues, the chemical interactions will not vary appreciably as a function of labelling. Reversed-phase liquid chromatography has been used to demonstrate that there are significant differences between the chromatographic behaviour of a sequence of deuterated and protonated oligomeric polystyrenes. Two-dimensional reversed-phase liquid chromatography was used to show that even the diasteromers of the oligomers (n = 5) have retention mechanisms that are dependent on the subtle changes to the molecular conformation and electronic structure, which are a consequence of deuteration.

  12. Ionic liquid and aqueous two-phase extraction based on salting-out coupled with high-performance liquid chromatography for the determination of seven rare ginsenosides in Xue-Sai-Tong injection.

    Science.gov (United States)

    Li, Lan-Jie; Jin, Yong-Ri; Wang, Xiao-Zhong; Liu, Ying; Wu, Qian; Shi, Xiao-Lei; Li, Xu-Wen

    2015-09-01

    A method of ionic liquid salt aqueous two-phase extraction coupled with high-performance liquid chromatography has been developed for the analysis of seven rare ginsenosides including Rg6 , F4 , 20(S)-Rg3 , 20(R)-Rg3 , Rk3 , Rk1 , and Rg5 in Xue-Sai-Tong injection. The injection was mixed with ionic liquid 1-butyl-3-methylimidazolium bromide aqueous solution, and a mixture was obtained. With the addition of sodium dodecyl sulfate and dipotassium phosphate into the mixture, the aqueous two-phase mixture was formed after ultrasonic treatment and centrifuged. Rare ginsenosides were extracted into the upper phase. To obtain a high extraction factors, various influences were considered systematically, such as the volume of ionic liquid, the category and amount of salts, the amount of sodium dodecyl sulfate, the pH value of system, and the time of ultrasonic treatment. Under the optimal condition, rare ginsenosides in Xue-Sai-Tong injection were enriched and detected, the recoveries of seven rare ginsenosides ranged from 90.05 to 112.55%, while relative standard deviations were lower than 2.50%. The developed method was reliable, rapid and sensitive for the determination of seven rare ginsenosides in the injections. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Development of a high performance liquid chromatography method and a liquid chromatography-tandem mass spectrometry method with pressurized liquid extraction for simultaneous quantification and confirmation of cyromazine, melamine and its metabolites in foods of animal origin

    International Nuclear Information System (INIS)

    Yu Huan; Tao Yanfei; Chen Dongmei; Wang Yulian; Liu Zhaoying; Pan Yuanhu; Huang Lingli; Peng Dapeng; Dai Menghong; Liu Zhenli; Yuan Zonghui

    2010-01-01

    Simple and sensitive methods have been developed for simultaneous detection of cyromazine, melamine and their metabolites (ammeline, ammelide and cyanuric acid) in samples of animal origins. These include a high performance liquid chromatography (HPLC) method and a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and are useful in regular monitoring and in toxicity studies of these molecules. Representative samples used in this study include muscles and livers of swine, bovine, sheep and chicken, kidneys of swine, bovine and sheep, and milk powder. A new sample preparation procedure with pressurized liquid extraction (PLE) at 1400 psi and 70 deg. C was investigated. Quantification of these five compounds by HPLC was achieved using an APS-2 column with UV detection at 230 nm. Limit of detection (LOD) was at 10 μg kg -1 , and limit of quantification (LOQ) was at 40 μg kg -1 . Recoveries of the five analytes in spiked samples ranged from 72.2% to 115.4% with RSD less than 12%. Confirmatory analysis of the analytes was performed using LC-MS/MS in selected reaction monitoring (SRM) mode. The LOD and LOQ were 5 μg kg -1 and 15 μg kg -1 , respectively. This is the first simultaneous analysis of cyromazine, melamine, ammeline, ammelide and cyanuric acid residues in complex tissue samples using PLE and HPLC. It is expected that these methods will find many practical applications in evaluating the safety of cyromazine, melamine and their metabolites.

  14. Parallel microscope-based fluorescence, absorbance and time-of-flight mass spectrometry detection for high performance liquid chromatography and determination of glucosamine in urine.

    Science.gov (United States)

    Xiong, Bo; Wang, Ling-Ling; Li, Qiong; Nie, Yu-Ting; Cheng, Shuang-Shuang; Zhang, Hui; Sun, Ren-Qiang; Wang, Yu-Jiao; Zhou, Hong-Bin

    2015-11-01

    A parallel microscope-based laser-induced fluorescence (LIF), ultraviolet-visible absorbance (UV) and time-of-flight mass spectrometry (TOF-MS) detection for high performance liquid chromatography (HPLC) was achieved and used to determine glucosamine in urines. First, a reliable and convenient LIF detection was developed based on an inverted microscope and corresponding modulations. Parallel HPLC-LIF/UV/TOF-MS detection was developed by the combination of preceding Microscope-based LIF detection and HPLC coupled with UV and TOF-MS. The proposed setup, due to its parallel scheme, was free of the influence from photo bleaching in LIF detection. Rhodamine B, glutamic acid and glucosamine have been determined to evaluate its performance. Moreover, the proposed strategy was used to determine the glucosamine in urines, and subsequent results suggested that glucosamine, which was widely used in the prevention of the bone arthritis, was metabolized to urines within 4h. Furthermore, its concentration in urines decreased to 5.4mM at 12h. Efficient glucosamine detection was achieved based on a sensitive quantification (LIF), a universal detection (UV) and structural characterizations (TOF-MS). This application indicated that the proposed strategy was sensitive, universal and versatile, and it was capable of improved analysis, especially for analytes with low concentrations in complex samples, compared with conventional HPLC-UV/TOF-MS. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Quantification of maltol in Korean ginseng (Panax ginseng) products by high-performance liquid chromatography-diode array detector

    Science.gov (United States)

    Jeong, Hyun Cheol; Hong, Hee-Do; Kim, Young-Chan; Rhee, Young Kyoung; Choi, Sang Yoon; Kim, Kyung-Tack; Kim, Sung Soo; Lee, Young-Chul; Cho, Chang-Won

    2015-01-01

    Background: Maltol, as a type of phenolic compounds, is produced by the browning reaction during the high-temperature treatment of ginseng. Thus, maltol can be used as a marker for the quality control of various ginseng products manufactured by high-temperature treatment including red ginseng. For the quantification of maltol in Korean ginseng products, an effective high-performance liquid chromatography-diode array detector (HPLC-DAD) method was developed. Materials and Methods: The HPLC-DAD method for maltol quantification coupled with a liquid-liquid extraction (LLE) method was developed and validated in terms of linearity, precision, and accuracy. An HPLC separation was performed on a C18 column. Results: The LLE methods and HPLC running conditions for maltol quantification were optimized. The calibration curve of the maltol exhibited good linearity (R2 = 1.00). The limit of detection value of maltol was 0.26 μg/mL, and the limit of quantification value was 0.79 μg/mL. The relative standard deviations (RSDs) of the data of the intra- and inter-day experiments were <1.27% and 0.61%, respectively. The results of the recovery test were 101.35–101.75% with an RSD value of 0.21–1.65%. The developed method was applied successfully to quantify the maltol in three ginseng products manufactured by different methods. Conclusion: The results of validation demonstrated that the proposed HPLC-DAD method was useful for the quantification of maltol in various ginseng products. PMID:26246746

  16. Development of High Performance Liquid Chromatography and Mass Spectrometry: a Key Engine of TCM Modernization

    Directory of Open Access Journals (Sweden)

    Zheng-Xiang Zhang

    2015-04-01

    Full Text Available Traditional Chinese Medicine (TCM has been popular for thousand years in prevention and treatment of chronic diseases synergistically with Western medicine while producing mild healing effects and lower side effects. Although many TCMs have been proven effective by modern pharmacological studies and clinical trials, their bioactive constituents and the remedial mechanisms are still not well understood. Researchers have made great efforts to explore the real theory of TCM for many years with different strategies. Development of high performance liquid chromatography (HPLC and mass spectrometry within recent decade can provide scientists with robust technologies for disclosing the mysterious mask of TCM. In this paper, important innovations of HPLC and mass spectrometry are reviewed in the application of TCM analysis from single compound identification to metabolomic strategy.

  17. Investigation of folic acid stability in fortified instant noodles by use of capillary electrophoresis and reversed-phase high performance liquid chromatography.

    Science.gov (United States)

    Hau Fung Cheung, Rodney; Morrison, Paul D; Small, Darryl M; Marriott, Philip J

    2008-12-05

    A single enzyme treatment with alpha-amylase, prior to the quantification of added folic acid (FA) in fortified instant fried Asian noodles with analysis performed by capillary zone electrophoresis (CZE) and reversed-phase high performance liquid chromatography (RP-HPLC) with UV detection, is described. The method was validated and optimized for capillary electrophoresis (CE) with separation achieved using a 8 mM phosphate-12 mM borate run buffer with 5% MeOH at pH 9.5. FA was well separated from matrix components with nicotinic acid (NA) employed as an internal standard. In a comparative study, separation of FA was performed using HPLC with a mobile phase consisting of 27% MeOH (v/v) in aqueous potassium phosphate buffer (3.5 mM KH(2)PO(4) and 3.2 mM K(2)HPO(4)), pH 8.5, and containing 5 mM tetrabutylammonium dihydrogen phosphate as an ion-pairing agent. For both methods, excellent results were obtained for various analytical parameters including linearity, accuracy and precision. The limit of detection was calculated to be 2.2 mg/L for CE without sample stacking and 0.10 mg/L with high performance liquid chromatography (HPLC). Sample extraction involved homogenization and enzymatic extraction with alpha-amylase. Results indicated that FA was stable during four main stages of instant fried noodle manufacturing (dough crumbs, cut sheets, steaming and frying).

  18. New and highly sensitive assay for L-5-hydroxytryptophan decarboxylase activity by high-performance liquid chromatography-voltammetry.

    Science.gov (United States)

    Rahman, M K; Nagatsu, T; Kato, T

    1980-12-12

    This paper describes a new, inexpensive and highly sensitive assay for aromatic L-amino acid decarboxylase (AADC) activity, using L-5-hydroxytryptophan (L-5-HTP) as substrate, in rat and human brains and serum by high-performance liquid chromatography (HPLC) with voltammetric detection. L-5-HTP was used as substrate and D-5-HTP for the blank. After isolating serotonin (5-HT) formed enzymatically from L-5-HTP on a small Amberlite CG-50 column, the 5-HT was eluted with hydrochloric acid and assayed by HPLC with a voltammetric detector. N-Methyldopamine was added to each incubation mixture as an internal standard. This method is sensitive enough to measure 5-HT, formed by the enzyme, 100 fmol to 140 pmol or more. An advantage of this method is that one can incubate the enzyme for longer time (up to 150 min), as compared with AADC assay using L-DOPA as substrate, resulting in a very high sensitivity. By using this new method, AADC activity was discovered in rat serum.

  19. 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.

  20. [Determination of phthalate plasticizers in foods by high performance liquid chromatography with gel permeation chromatographic clean-up].

    Science.gov (United States)

    Zhang, Chunyu; Wang, Hui; Zhang, Xiaohui; Ma, Zhongqiang; Deng, Wanmei; Hu, Ke; Ding, Mingyu

    2011-12-01

    A method of gel permeation chromatography-high performance liquid chromatography (GPC-HPLC) was established for the simultaneous determination of 5 main phthalate plasticizers in foods (edible oil, instant noodles, fried pastries, Saqima, etc.). The samples were extracted with petroleum ether in an ultrasonator, purified by a GPC column, and analyzed by HPLC. The chromatographic separation was achieved on a Labtech-C18 column (250 mm x 4.6 mm, 5 microm) using acetonitrile and water mixture as the mobile phases in a gradient elution mode. The developed method exhibited a linear correlation coefficient of more than 0.997 and the detection limits of 3.25 - 13.4 microg/L. The spike recoveries were between 70.4% and 113.6% with the relative standard deviations (RSDs, n = 3) of 0.3% - 5.8% at the spiked level of 50 mg/L. This method is simple, rapid and practical, and can be used for the simultaneous determination of PAEs in grease food samples.

  1. Dual ultrasonic-assisted dispersive liquid-liquid microextraction coupled with microwave-assisted derivatization for simultaneous determination of 20(S)-protopanaxadiol and 20(S)-protopanaxatriol by ultra high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Zhao, Xian-En; Lv, Tao; Zhu, Shuyun; Qu, Fei; Chen, Guang; He, Yongrui; Wei, Na; Li, Guoliang; Xia, Lian; Sun, Zhiwei; Zhang, Shijuan; You, Jinmao; Liu, Shu; Liu, Zhiqiang; Sun, Jing; Liu, Shuying

    2016-03-11

    This paper, for the first time, reported a speedy hyphenated technique of low toxic dual ultrasonic-assisted dispersive liquid-liquid microextraction (dual-UADLLME) coupled with microwave-assisted derivatization (MAD) for the simultaneous determination of 20(S)-protopanaxadiol (PPD) and 20(S)-protopanaxatriol (PPT). The developed method was based on ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection using multiple-reaction monitoring (MRM) mode. A mass spectrometry sensitizing reagent, 4'-carboxy-substituted rosamine (CSR) with high reaction activity and ionization efficiency was synthesized and firstly used as derivatization reagent. Parameters of dual-UADLLME, MAD and UHPLC-MS/MS conditions were all optimized in detail. Low toxic brominated solvents were used as extractant instead of traditional chlorinated solvents. Satisfactory linearity, recovery, repeatability, accuracy and precision, absence of matrix effect and extremely low limits of detection (LODs, 0.010 and 0.015ng/mL for PPD and PPT, respectively) were achieved. The main advantages were rapid, sensitive and environmentally friendly, and exhibited high selectivity, accuracy and good matrix effect results. The proposed method was successfully applied to pharmacokinetics of PPD and PPT in rat plasma. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. A simple high-performance liquid chromatography for the determination of linezolid in human plasma and saliva.

    Science.gov (United States)

    Hara, Shuuji; Uchiyama, Masanobu; Yoshinari, Masami; Matsumoto, Taichi; Jimi, Shiro; Togawa, Atsushi; Takata, Tohru; Takamatsu, Yasushi

    2015-09-01

    Linezolid is an antimicrobial agent for the treatment of multiresistant Gram-positive infections. A practical high-performance liquid chromatography method was developed for the determination of linezolid in human plasma and saliva. Linezolid and an internal standard (o-ethoxybenzamide) were extracted from plasma and saliva with ethyl acetate and analyzed on a Capcell Pak C18 MG column with UV detection at 254 nm. The calibration curve was linear through the range 0.5-50 µg/mL using a 200 μL sample volume. The intra- and interday precisions were all plasma and 5.60% for saliva. The accuracies ranged from 98.8 to 110% for both matrices. The mean recoveries of linezolid were 80.8% for plasma and 79.0% for saliva. This method was used to determine the plasma and saliva concentrations of linezolid in healthy volunteers who were orally administered a 600 mg dose of linezolid. Our liquid-liquid extraction procedure is easy and requires a small volume of plasma or saliva (200 μL). This small volume can be advantageous in clinical pharmacokinetic studies, especially if children participate. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Evaluating the Antibacterial Properties of Polyacetylene and Glucosinolate Compounds with Further Identification of Their Presence within Various Carrot (Daucus carota) and Broccoli (Brassica oleracea) Cultivars Using High-Performance Liquid Chromatography with a Diode Array Detector and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry Analyses.

    Science.gov (United States)

    Hinds, L; Kenny, O; Hossain, M B; Walsh, D; Sheehy, E; Evans, P; Gaffney, M; Rai, D K

    2017-08-23

    Ongoing consumer concerns over using synthetic additives in foods has strongly influenced efforts worldwide to source suitable natural alternatives. In this study, the antibacterial efficacy of polyacetylene and glucosinolate compounds was evaluated against both Gram positive and Gram negative bacterial strains. Falcarinol [minimum inhibitory concentration (MIC) = 18.8-37.6 μg/mL] demonstrated the best overall antibacterial activity, while sinigrin (MIC = 46.9-62.5 μg/mL) was the most active glucosinolate compound. High-performance liquid chromatography with a diode array detector analysis showed falcarinol [85.13-244.85 μg/g of dry weight (DW)] to be the most abundant polyacetylene within six of the eight carrot (Daucus carota) cultivars investigated. Meanwhile, sinigrin (100.2-244.3 μg/g of DW) was the most abundant glucosinolate present within the majority of broccoli (Brassica oleracea) cultivars investigated using ultra performance liquid chromatography-tandem mass spectrometry analysis. The high abundance of both falcarinol and sinigrin within these respective species suggests that they could serve as potential sources of natural antibacterial agents for use as such in food products.

  4. The high pressure liquid chromatography and its application to the separation of polynuclear aromatic hydrocarbons in atmospheric dust and burning residues

    International Nuclear Information System (INIS)

    Lopez, M.-C.

    1975-09-01

    A new technique of analysis is described: the high speed liquid chromatography or more exactly the high performance liquid chromatography because of the progress achieved on the new packings of the columns. The main types of chromatography, according to the phenomena involved are described: adsorption, partition, ion-exchange and exclusion chromatography. A brief outline is given of the theory for determination of stationary and mobile phases in order to obtain the optimum conditions of separation. Some exemples of possible applications are given, particularly the use of this technique for the separation of polycyclic aromatic hydrocarbons in atmospheric pollution and burning residues [fr

  5. Determination of Bisphenol A and Bisphenol AF in Vinegar samples by two-component mixed ionic liquid dispersive liquid-phase microextraction coupled with high performance liquid chromatography

    International Nuclear Information System (INIS)

    Tai, Z.; Liu, M.; Hu, X.; Yang, Y.

    2014-01-01

    This paper describes a sensitive and simple method for the determination of bisphenol A (BPA) and bisphenol AF (BPAF) in vinegar samples using two-component mixed ionic liquid dispersive liquid-phase microextraction coupled with high performance liquid chromatography. In this work, BPA and BPAF were selected as the model analytes, and two-component mixed ionic liquid included 1-butyl-3-methylimidazolium hexafluorophosphate ((C4Mim)PF6) and 1-hexyl-3-methyl-imidazolium hexafluorophosphate ((C6Mim)PF6) was used as the extraction solvent for the first time here. Parameters that affect the extraction efficiency were investigated. Under the optimum conditions, good linear relationships were discovered in the range of 1.0-100 micro g/L for BPA and 2.0-150 micro g/L for BPAF, respectively. Detection limits of proposed method based on the signal-to-noise ratio (S/N=3) were in the range of 0.15-0.38 micro g/L. The efficiencies of proposed method have also been demonstrated with spiked real vinegar samples. The result show this method/ procedure to be a more efficient approach for the determination of BPA and BPAF in real vinegar, presenting average recovery rate of 89.3-112 % and precision values of 0.9-13.5% (RSDs, n = 6). In comparison with traditional solid phase extraction procedures this method results in lower solvent consumption, low pollution levels, and faster sample preparation. (author)

  6. [Determination of emamectin benzoate residue in vegetables by high performance liquid chromatography with fluorescence detection].

    Science.gov (United States)

    Zhang, Yan; Wu, Yinliang; Hu, Jiye; Wang, Hongwei; Pan, Canping; Liu, Fengmao

    2008-01-01

    A method was developed for the determination of emamectin benzoate residue in cabbage and mushroom using solid-phase extraction (SPE) and high performance liquid chromatography (HPLC) with fluorescence detection. The sample was extracted with ethyl acetate. Further cleanup was performed on a propylsulfonic acid solid phase extraction cartridge, followed by the derivatization with trifluoroacetic anhydride in the presence of N-methylimidazole. The amount of derivatized emamectin benzoate was determined by fluorescence detector after separation by HPLC. The detection limit was 0.10 microg/kg for cabbage and mushroom samples. The recoveries of emamectin benzoate in cabbage and mushroom samples were 78.6%-84.9%. The inter-day relative standard deviation (RSD) and intra-day RSD were 2.7%-6.0% and 3.1%-8.9%, respectively, at the fortified levels of 1.0-20.0 microg/kg. The calibration curve of emamectin benzoate in vegetables at the concentration range of 0.002 mg/L to 0.10 mg/L was linear (r = 0.9999).

  7. Determination of drug lipophilicity by phosphatidylcholine-modified microemulsion high-performance liquid chromatography.

    Science.gov (United States)

    Xuan, Xueyi; Xu, Liyuan; Li, Liangxing; Gao, Chongkai; Li, Ning

    2015-07-25

    A new biomembrane-mimetic liquid chromatographic method using a C8 stationary phase and phosphatidylcholine-modified (PC-modified) microemulsion mobile phase was used to estimate unionized and ionized drugs lipophilicity expressed as an n-octanol/water partition coefficient (logP and logD). The introduction of PC into sodium dodecyl sulfate (SDS) microemulsion yielded a good correlation between logk and logD (R(2)=0.8). The optimal composition of the PC-modified microemulsion liquid chromatography (PC-modified MELC) mobile phase was 0.2% PC-3.0% SDS-6.0% n-butanol-0.8% ethyl acetate-90.0% water (pH 7.0) for neutral and ionized molecules. The interactions between the analytes and system described by this chromatographic method is more similar to biological membrane than the n-octanol/water partition system. The result in this paper suggests that PC-modified MELC can serve as a possible alternative to the shake-flask method for high-throughput unionized and ionized drugs lipophilicity determination and simulation of biological processes. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Assessment of Dopaminergic Homeostasis in Mice by Use of High-performance Liquid Chromatography Analysis and Synaptosomal Dopamine Uptake

    DEFF Research Database (Denmark)

    Jensen, Kathrine L; Runegaard, Annika H; Weikop, Pia

    2017-01-01

    Dopamine (DA) is a modulatory neurotransmitter controlling motor activity, reward processes and cognitive function. Impairment of dopaminergic (DAergic) neurotransmission is strongly associated with several central nervous system-associated diseases such as Parkinson's disease, attention...... therapeutic targets for these diseases. Here, we present two useful experimental protocols that when combined provide a functional read-out of the DAergic system in mice. Biochemical and functional parameters on DA homeostasis are obtained through assessment of DA levels and dopamine transporter (DAT......) functionality(5). When investigating the DA system, the ability to reliably measure endogenous levels of DA from adult brain is essential. Therefore, we present how to perform high-performance liquid chromatography (HPLC) on brain tissue from mice to determine levels of DA. We perform the experiment on tissue...

  9. Gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection for dating of paper ink.

    Science.gov (United States)

    Díaz-Santana, Oscar; Vega-Moreno, Daura; Conde-Hardisson, Francisco

    2017-09-15

    An extraction and determination method is shown for the analysis of dyes and solvents present in two types of ballpoint pen inks that are deposited onto paper. Ink extracts are analysed using a combination of gas chromatography with mass spectrometry (GC-MS), and high-pressure liquid chromatography with photodiode array detection (HPLC-DAD), within a single sample extraction procedure. Seventeen solvents and thirteen dyes contained in two Montblanc ® inks (black and blue) were monitored for 45 months at monthly intervals, in order to determine variations in the concentrations of the compounds over time. We also studied the relative variations between different compounds and the generation of degradation products such as phenol. The concentration data obtained from these compounds during their exposure have been analysed and a multiple regression model is developed for each ink type that allows an estimate of the exposure time of the ink on paper with a maximum error of between 4 and 7 months. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Determination of phenolic compounds using high-performance liquid chromatography with Ce4+-Tween 20 chemiluminescence detection

    International Nuclear Information System (INIS)

    Cui Hua; Zhou Jian; Xu Feng; Lai Chunze; Wan Guohui

    2004-01-01

    A novel method for the simultaneous determination of phenolic compounds such as salicylic acid, resorcinol, phloroglucinol, p-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, and m-nitrophenol by high-performance liquid chromatography (HPLC) coupled with chemiluminescence (CL) detection was developed. The procedure was based on the chemiluminescent enhancement by phenolic compounds of the cerium(IV)-Tween 20 system in a sulfuric acid medium. The separation was carried out with an isocratic elution or with a gradient elution using a mixture of methanol and 1.5% acetic acid. For six phenolic compounds, the detection limits (3σ) were in the range 1.40-5.02 ng/ml and the relative standard deviations (n=11) for the determination of 0.1 μg/ml compounds were in the range 1.9-2.9%. The CL reaction was well compatible with the mobile phase of HPLC, no baseline drift often occurred in HPLC-CL detection was observed with a gradient elution. The method has been successfully applied to the determination of salicylic acid and resorcinol in Dermatitis Clear Tincture and p-hydroxybenzoic acid in apple juices

  11. Ionic liquid stationary phases for gas chromatography.

    Science.gov (United States)

    Poole, Colin F; Poole, Salwa K

    2011-04-01

    This article provides a summary of the development of ionic liquids as stationary phases for gas chromatography beginning with early work on packed columns that established details of the retention mechanism and established working methods to characterize selectivity differences compared with molecular stationary phases through the modern development of multi-centered cation and cross-linked ionic liquids for high-temperature applications in capillary gas chromatography. Since there are many reviews on ionic liquids dealing with all aspects of their chemical and physical properties, the emphasis in this article is placed on the role of gas chromatography played in the design of ionic liquids of low melting point, high thermal stability, high viscosity, and variable selectivity for separations. Ionic liquids provide unprecedented opportunities for extending the selectivity range and temperature-operating range of columns for gas chromatography, an area of separation science that has otherwise been almost stagnant for over a decade. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Countercurrent chromatography separation of saponins by skeleton type from Ampelozizyphus amazonicus for off-line ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry analysis and characterisation.

    Science.gov (United States)

    de Souza Figueiredo, Fabiana; Celano, Rita; de Sousa Silva, Danila; das Neves Costa, Fernanda; Hewitson, Peter; Ignatova, Svetlana; Piccinelli, Anna Lisa; Rastrelli, Luca; Guimarães Leitão, Suzana; Guimarães Leitão, Gilda

    2017-01-20

    Ampelozizyphus amazonicus Ducke (Rhamnaceae), a medicinal plant used to prevent malaria, is a climbing shrub, native to the Amazonian region, with jujubogenin glycoside saponins as main compounds. The crude extract of this plant is too complex for any kind of structural identification, and HPLC separation was not sufficient to resolve this issue. Therefore, the aim of this work was to obtain saponin enriched fractions from the bark ethanol extract by countercurrent chromatography (CCC) for further isolation and identification/characterisation of the major saponins by HPLC and MS. The butanol extract was fractionated by CCC with hexane - ethyl acetate - butanol - ethanol - water (1:6:1:1:6; v/v) solvent system yielding 4 group fractions. The collected fractions were analysed by UHPLC-HRMS (ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry) and MS n . Group 1 presented mainly oleane type saponins, and group 3 showed mainly jujubogenin glycosides, keto-dammarane type triterpene saponins and saponins with C 31 skeleton. Thus, CCC separated saponins from the butanol-rich extract by skeleton type. A further purification of group 3 by CCC (ethyl acetate - ethanol - water (1:0.2:1; v/v)) and HPLC-RI was performed in order to obtain these unusual aglycones in pure form. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Sensitive quantification of coixol, a potent insulin secretagogue, in Scoparia dulcis extract using high-performance liquid chromatography combined with tandem mass spectrometry and UV detection.

    Science.gov (United States)

    Ali, Arslan; Haq, Faraz Ul; Ul Arfeen, Qamar; Sharma, Khaga Raj; Adhikari, Achyut; Musharraf, Syed Ghulam

    2017-10-01

    Diabetes is a major global health problem which requires new studies for its prevention and control. Scoparia dulcis, a herbal product, is widely used for treatment of diabetes. Recent studies demonstrate coixol as a potent and nontoxic insulin secretagog from S. dulcis. This study focuses on developing two quantitative methods of coixol in S. dulcis methanol-based extracts. Quantification of coixol was performed using high-performance liquid chromatography-tandem mass spectrometry (method 1) and high-performance liquid chromatography-ultraviolet detection (method 2) with limits of detection of 0.26 and 11.6 pg/μL, respectively, and limits of quantification of 0.78 and 35.5 pg/μL, respectively. S. dulcis is rich in coixol content with values of 255.5 ± 2.1 mg/kg (method 1) and 220.4 ± 2.9 mg/kg (method 2). Excellent linearity with determination coefficients >0.999 was achieved for calibration curves from 10 to 7500 ng/mL (method 1) and from 175 to 7500 ng/mL (method 2). Good accuracy (bias < -8.6%) and precision (RSD < 8.5%) were obtained for both methods. Thus, they can be employed to analyze coixol in plant extracts and herbal formulations. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Comprehensive sample analysis using high performance liquid chromatography with multi-detection

    International Nuclear Information System (INIS)

    Pravadali, Sercan; Bassanese, Danielle N.; Conlan, Xavier A.; Francis, Paul S.; Smith, Zoe M.; Terry, Jessica M.; Shalliker, R. Andrew

    2013-01-01

    Graphical abstract: -- Highlights: •Detection selectivity was assessed with 6 detection modes. •Natural samples show great diversity in detection selectivity. •Complex samples require evaluation using a multifaceted approach to detection. •23/30 known compounds (detected by MS) detected by chemiluminescence, DPPH and UV. -- Abstract: Herein we assess the separation space offered by a liquid chromatography system with an optimised uni-dimensional separation for the determination of the key chemical entities in the highly complex matrix of a tobacco leaf extract. Multiple modes of detection, including UV–visible absorbance, chemiluminescence (acidic potassium permanganate, manganese(IV), and tris(2,2′-bipyridine)ruthenium(III)), mass spectrometry and DPPH radical scavenging were used in an attempt to systematically reduce the data complexity of the sample whilst obtaining a greater degree of molecule-specific information. A large amount of chemical data was obtained, but several limitations in the ability to assign detector responses to particular compounds, even with the aid of complementary detection systems, were observed. Thirty-three compounds were detected via MS on the tobacco extract and 12 out of 32 compounds gave a peak height ratio (PHR) greater than 0.33 on one or more detectors. This paper serves as a case study of these limitations, illustrating why multidimensional chromatography is an important consideration when developing a comprehensive chemical detection system

  15. Comprehensive sample analysis using high performance liquid chromatography with multi-detection

    Energy Technology Data Exchange (ETDEWEB)

    Pravadali, Sercan [Australian Centre for Research on Separation Sciences (ACROSS), School of Science and Health, University of Western Sydney (Parramatta), NSW 1797 (Australia); Bassanese, Danielle N.; Conlan, Xavier A.; Francis, Paul S.; Smith, Zoe M.; Terry, Jessica M. [Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Victoria 3216 (Australia); Shalliker, R. Andrew, E-mail: R.Shalliker@uws.edu.au [Australian Centre for Research on Separation Sciences (ACROSS), School of Science and Health, University of Western Sydney (Parramatta), NSW 1797 (Australia)

    2013-11-25

    Graphical abstract: -- Highlights: •Detection selectivity was assessed with 6 detection modes. •Natural samples show great diversity in detection selectivity. •Complex samples require evaluation using a multifaceted approach to detection. •23/30 known compounds (detected by MS) detected by chemiluminescence, DPPH and UV. -- Abstract: Herein we assess the separation space offered by a liquid chromatography system with an optimised uni-dimensional separation for the determination of the key chemical entities in the highly complex matrix of a tobacco leaf extract. Multiple modes of detection, including UV–visible absorbance, chemiluminescence (acidic potassium permanganate, manganese(IV), and tris(2,2′-bipyridine)ruthenium(III)), mass spectrometry and DPPH radical scavenging were used in an attempt to systematically reduce the data complexity of the sample whilst obtaining a greater degree of molecule-specific information. A large amount of chemical data was obtained, but several limitations in the ability to assign detector responses to particular compounds, even with the aid of complementary detection systems, were observed. Thirty-three compounds were detected via MS on the tobacco extract and 12 out of 32 compounds gave a peak height ratio (PHR) greater than 0.33 on one or more detectors. This paper serves as a case study of these limitations, illustrating why multidimensional chromatography is an important consideration when developing a comprehensive chemical detection system.

  16. Analysis of Fluconazole in Human Urine Sample by High Performance Liquid Chromatography Method

    International Nuclear Information System (INIS)

    Hermawan, D; Ali, N A Md; Ibrahim, W A Wan; Sanagi, M M

    2013-01-01

    A method for determination of fluconazole, antifungal drug in human urine by using reversed-phased high performance liquid chromatography (RP-HPLC) with ultraviolet (UV) detector was developed. Optimization HPLC conditions were carried out by changing the flow rate and composition of mobile phase. The optimum separation conditions at a flow rate 0.85 mL/min with a composition of mobile phase containing methanol:water (70:30, v/v) with UV detection at a wavelength 254 nm was able to analyze fluconazole within 3 min. The excellent linearity was obtained in the range of concentration 1 to 10 μg/mL with r 2 = 0.998. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.39 μg/mL and 1.28 μg/mL, respectively. Solid phase extraction (SPE) method using octadecylsilane (C18) as a sorbent was used to clean-up and pre-concentrated of the urine sample prior to HPLC analysis. The average recoveries of fluconazole in spiked urine sample was 72.4% with RSD of 3.21% (n=3).

  17. Simultaneous determination of five major compounds in the traditional medicine Pyeongwee-San by high performance liquid chromatography-diode array detection and liquid chromatography-mass spectrometry/mass spectrometry.

    Science.gov (United States)

    Lee, Bohyoung; Weon, Jin Bae; Yun, Bo-Ra; Lee, Jiwoo; Eom, Min Rye; Ma, Choong Je

    2014-01-01

    Pyeongwee-San (PWS) has been widely used for treating acute gastritis, chronic, and gastritis. In this paper, simultaneous determination of five compounds (naringin, hesperidin, glycyrrhizin, atractylenolide III, and magnolol) from traditional medicine PWS using the high performance liquid chromatography (HPLC) was established for quality control. Optimum separations were obtained with a SHISEIDO C18 reverse-phase column by gradient elution with 0.1% Trifluoroacetic acid (TFA) water-acetonitrile as the mobile phase. The flow rate was 1 mL/min and detection wavelength was set at 205 nm and 250 nm. Validation of the analytical method was evaluated by linearity, precision, and accuracy test. The calibration curves were linear over the established range with R (2) > 0.9978. The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.09 to 0.43 and 0.27 to 1.29 μg/mL. The method exhibited intra-day and inter-day precision range between 0.01-1.86% and 0.04-0.35% respectively. The recoveries of five compounds in PWS were in the range between 93.18-106.40%, and 0.20-1.51%. The application of this method was identified through the successful analysis of five compounds in 12 batches of PWS. In addition, identification of five compounds was confirmed by a liquid chromatography method and mass spectrometry. The HPLC method was could be accomplished to the quality control and stable experiment for the preparations consisted of five major compounds.

  18. Investigating the Retention Mechanisms of Liquid Chromatography Using Solid-Phase Extraction Cartridges

    Science.gov (United States)

    O'Donnell, Mary E.; Musial, Beata A.; Bretz, Stacey Lowery; Danielson, Neil D.; Ca, Diep

    2009-01-01

    Liquid chromatography (LC) experiments for the undergraduate analytical laboratory course often illustrate the application of reversed-phase LC to solve a separation problem, but rarely compare LC retention mechanisms. In addition, a high-performance liquid chromatography instrument may be beyond what some small colleges can purchase. Solid-phase…

  19. Quantification of Oxidized and Unsaturated Bile Alcohols in Sea Lamprey Tissues by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Ke Li

    2016-08-01

    Full Text Available A sensitive and reliable method was developed and validated for the determination of unsaturated bile alcohols in sea lamprey tissues using liquid-liquid extraction and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS. The liver, kidney, and intestine samples were extracted with acetonitrile and defatted by n-hexane. Gradient UHPLC separation was performed using an Acquity BEH C18 column with a mobile phase of water and methanol containing 20 mM triethylamine. Multiple reaction monitoring modes of precursor-product ion transitions for each analyte was used. This method displayed good linearity, with correlation coefficients greater than 0.99, and was validated. Precision and accuracy (RSD % were in the range of 0.31%–5.28%, while mean recoveries were between 84.3%–96.3%. With this technique, sea lamprey tissue samples were analyzed for unsaturated bile alcohol analytes. This method is practical and particularly suitable for widespread putative pheromone residue analysis.

  20. Comparison of high-performance liquid chromatography/tandem mass spectrometry and high-performance liquid chromatography/photo-diode array detection for the quantitation of carotenoids, retinyl esters, α-tocopherol and phylloquinone in chylomicron-rich fractions of human plasma.

    Science.gov (United States)

    Kopec, Rachel E; Schweiggert, Ralf M; Riedl, Ken M; Carle, Reinhold; Schwartz, Steven J

    2013-06-30

    Bioavailability of essential lipophilic micronutrients and carotenoids is of utmost interest for human health, as the consumption of these compounds may help alleviate major nutritional deficiencies, cardiovascular disease, and cancer. High-performance liquid chromatography/photo-diode array detection (HPLC-PDA) and high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) were compared for the quantitative analysis of α- and β-carotene, β-cryptoxanthin, lutein, lycopene, α-tocopherol, phylloquinone, and several retinyl esters from chylomicron-containing triglyceride rich lipoprotein (TRL) fractions of human plasma obtained from two clinical trials. After selecting an efficient extraction method for the analytes, both the HPLC/PDA and the HPLC/MS/MS methods were developed and several parameters validated using an HP 1200 series HPLC system interfaced with a HP 1200 series diode-array detector (Agilent Technologies, Santa Clara, CA, USA) and a QTRAP 5500 (AB Sciex, Foster City, CA, USA) via an atmospheric pressure chemical ionization (APCI) probe operated in positive ion mode. For lycopene, α- and β-carotene, HPLC/MS/MS was up to 37 times more sensitive than HPLC-PDA. PDA detection was shown to be up to 8 times more sensitive for lutein. MS/MS signals were enhanced by matrix components for lutein and β-cryptoxanthin, as determined by referencing to the matrix-independent PDA signal. In contrast, matrix suppression was observed for retinyl palmitate, α-carotene, and β-carotene. Both detectors showed similar suitability for α-tocopherol, lycopene and retinyl palmitate (representing ~73% of total retinyl esters). MS/MS exclusively allowed the quantitation of minor retinyl esters, phylloquinone, and (Z)-lycopene isomers. HPLC/MS/MS was more sensitive than HPLC-PDA for six of the eight analytes and represents a powerful tool for the analysis of chylomicron samples and potentially other biological samples of limited sample size. When internal

  1. A high performance liquid chromatography method for determination of furfural in crude palm oil.

    Science.gov (United States)

    Loi, Chia Chun; Boo, Huey Chern; Mohammed, Abdulkarim Sabo; Ariffin, Abdul Azis

    2011-09-01

    A modified steam distillation method was developed to extract furfural from crude palm oil (CPO). The collected distillates were analysed using high performance liquid chromatography (HPLC) coupled with an ultraviolet diode detector at 284nm. The HPLC method allowed identification and quantification of furfural in CPO. The unique thermal extraction of CPO whereby the fresh fruit bunches (FFB) are first subjected to steam treatment, distinguishes itself from other solvent-extracted or cold-pressed vegetable oils. The presence of furfural was also determined in the fresh palm oil from FFB (without undergoing the normal extraction process), palm olein, palm stearin, olive oil, coconut oil, sunflower oil, soya oil and corn oil. The chromatograms of the extracts were compared to that of standard furfural. Furfural was only detected in CPO. The CPO consignments obtained from four mills were shown to contain 7.54 to 20.60mg/kg furfural. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Simultaneous determination of phenytoin, carbamazepine, and 10,11-carbamazepine epoxide in human plasma by high-performance liquid chromatography with ultraviolet detection.

    Science.gov (United States)

    Bhatti, M M; Hanson, G D; Schultz, L

    1998-03-01

    The Bioanalytical Chemistry Department at the Madison facility of Covance Laboratories, has developed and validated a simple and sensitive method for the simultaneous determination of phenytoin (PHT), carbamazepine (CBZ) and 10,11-carbamazepine epoxide (CBZ-E) in human plasma by high-performance liquid chromatography with 10,11 dihydrocarbamazepine as the internal standard. Acetonitrile was added to plasma samples containing PHT, CBZ and CBZ-E to precipitate the plasma proteins. After centrifugation, the acetonitrile supernatant was transferred to a clean tube and evaporated under N2. The dried sample extract was reconstituted in 0.4 ml of mobile phase and injected for analysis by high-performance liquid chromatography. Separation was achieved on a Spherisorb ODS2 analytical column with a mobile phase of 18:18:70 acetonitrile:methanol:potassium phosphate buffer. Detection was at 210 nm using an ultraviolet detector. The mean retention times of CBZ-E, PHT and CBZ were 5.8, 9.9 and 11.8 min, respectively. Peak height ratios were fit to a least squares linear regression algorithm with a 1/(concentration)2 weighting. The method produces acceptable linearity, precision and accuracy to a minimum concentration of 0.050 micrograms ml-1 in human plasma. It is also simple and convenient, with no observable matrix interferences.

  3. Analysis of Theobromine and Related Compounds by Reversed Phase High-Performance Liquid Chromatography with Ultraviolet Detection: An Update (1992–2011

    Directory of Open Access Journals (Sweden)

    Sandra Aparecida de Assis

    2011-01-01

    Full Text Available Theobromine and its related compounds, such as caffeine and theophylline, are secondary metabolites that belong to the alkaloids and have economic and cultural importance. These alkaloids have demonstrated stimulatory effects on the central nervous, gastrointestinal, cardiovascular, renal and respiratory systems, resulting in 'energy arousal', increased motivation to work, increased alertness and increased cognitive function. Several analytical methods have been used to analyse these compounds, but reversed phase high-performance liquid chromatography (RP-HPLC is the most commonly applied because of its efficiency, sensitivity, specificity and speed. This review describes the analyses of theobromine-related compounds by RP-HPLC with ultraviolet detection (UV in four sources: food, beverages, biological fluids and plants. Many RP-HPLC methods have been developed and optimized for the detection and quantification of these natural compounds. Elution under isocratic conditions is the most frequent method, with a water, methanol and acetonitrile mixture modified with acetic, phosphoric or formic acid as the mobile phase. For xanthine analysis, the use of reversed phase high-performance liquid chromatography with an ultraviolet/diode array detector (UV/DAD is particularly suitable as derivation is not required; it allows the analysis of absorbance at all wavelengths, it is simple and rapid.

  4. Optimizing separations in online comprehensive two-dimensional liquid chromatography.

    Science.gov (United States)

    Pirok, Bob W J; Gargano, Andrea F G; Schoenmakers, Peter J

    2018-01-01

    Online comprehensive two-dimensional liquid chromatography has become an attractive option for the analysis of complex nonvolatile samples found in various fields (e.g. environmental studies, food, life, and polymer sciences). Two-dimensional liquid chromatography complements the highly popular hyphenated systems that combine liquid chromatography with mass spectrometry. Two-dimensional liquid chromatography is also applied to the analysis of samples that are not compatible with mass spectrometry (e.g. high-molecular-weight polymers), providing important information on the distribution of the sample components along chemical dimensions (molecular weight, charge, lipophilicity, stereochemistry, etc.). Also, in comparison with conventional one-dimensional liquid chromatography, two-dimensional liquid chromatography provides a greater separation power (peak capacity). Because of the additional selectivity and higher peak capacity, the combination of two-dimensional liquid chromatography with mass spectrometry allows for simpler mixtures of compounds to be introduced in the ion source at any given time, improving quantitative analysis by reducing matrix effects. In this review, we summarize the rationale and principles of two-dimensional liquid chromatography experiments, describe advantages and disadvantages of combining different selectivities and discuss strategies to improve the quality of two-dimensional liquid chromatography separations. © 2017 The Authors. Journal of Separation Science published by WILEY-VCH Verlag GmbH & Co. KGaA.

  5. Determination of type A trichothecenes in coix seed by magnetic solid-phase extraction based on magnetic multi-walled carbon nanotubes coupled with ultra-high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Dong, Maofeng; Si, Wenshuai; Wang, Weimin; Bai, Bing; Nie, Dongxia; Song, Weiguo; Zhao, Zhihui; Guo, Yirong; Han, Zheng

    2016-09-01

    Magnetic solid-phase extraction (m-SPE) is a promising sample preparation approach due to its convenience, speed, and simplicity. For the first time, a rapid and reliable m-SPE approach using magnetic multi-walled carbon nanotubes (m-MWCNTs) as the adsorbent was proposed for purification of type A trichothecenes including T-2 toxins (T2), HT-2 toxins (HT-2), diacetoxyscirpenol (DAS), and neosolaniol (NEO) in coix seed. The m-MWCNTs were synthesized by assembling the magnetic nanoparticles (Fe3O4) with MWCNTs by sonication through an aggregation wrap mechanism, and characterized by transmission electron microscope. Several key parameters affecting the performance of the procedure were extensively investigated including extraction solutions, desorption solvents, and m-MWCNT amounts. Under the optimal sample preparation conditions followed by analysis with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), high sensitivity (limit of quantification in the range of 0.3-1.5 μg kg(-1)), good linearity (R (2) > 0.99), satisfactory recovery (73.6-90.6 %), and acceptable precision (≤2.5 %) were obtained. The analytical performance of the developed method has also been successfully evaluated in real coix seed samples. Graphical Abstract Flow chart of determination of type A trichothecenes in coix seed by magnetic solid-phase extraction coupled with ultra-high performance liquid chromatography-tandem mass spectrometry.

  6. Determination of three estrogens and bisphenol A by functional ionic liquid dispersive liquid-phase microextraction coupled with ultra-high performance liquid chromatography and ultraviolet detection.

    Science.gov (United States)

    Jiang, Yuehuang; Tang, Tingting; Cao, Zhen; Shi, Guoyue; Zhou, Tianshu

    2015-06-01

    A hydroxyl-functionalized ionic liquid, 1-hydroxyethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, was employed in an improved dispersive liquid-phase microextraction method coupled with ultra high performance liquid chromatography for the enrichment and determination of three estrogens and bisphenol A in environmental water samples. The introduced hydroxyl group acted as the H-bond acceptor that dispersed the ionic liquid effectively in the aqueous phase without dispersive solvent or external force. Fourier transform infrared spectroscopy indicated that the hydroxyl group of the cation of the ionic liquid enhanced the combination of extractant and analytes through the formation of hydrogen bonds. The improvement of the extraction efficiency compared with that with the use of alkyl ionic liquid was proved by a comparison study. The main parameters including volume of extractant, temperature, pH, and extraction time were investigated. The calibration curves were linear in the range of 5.0-1000 μg/L for estrone, estradiol, and bisphenol A, and 10.0-1000 μg/L for estriol. The detection limits were in the range of 1.7-3.4 μg/L. The extraction efficiency was evaluated by enrichment factor that were between 85 and 129. The proposed method was proved to be simple, low cost, and environmentally friendly for the determination of the four endocrine disruptors in environmental water samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Matrix effect in analysis of pesticide residues in fruits and vegetables by high performance liquid chromatography with quadrupole-time of flight mass spectrometry

    Directory of Open Access Journals (Sweden)

    Andoralov A.M.

    2017-03-01

    Full Text Available For modern food safety control are using techniques that allow to determinate a large number of components. So for determination of pesticide residues in fruits and vegetables commonly used methods of gas and liquid chromatography with time-of-flight mass-spectrometric detection. This system allows to carry out quantitative determination several hundreds of pesticides and their identification by the characteristic fragments of the mass spectrum. The main problem when using mass spectrometric detection is a matrix effect, which is caused by the influence of matrix components extracted with pesticides from the sample. In this work, attempts have been made to reduce the influence of the matrix in the analysis of pesticide residues by high performance liquid chromatography with time of flight mass spectrometry (HPLC / TOFMS.

  8. Sensitive determination of 4-O-methylhonokiol in rabbit plasma by high performance liquid chromatography and application to its pharmacokinetic investigation

    Directory of Open Access Journals (Sweden)

    Ming-Yue Li

    2011-05-01

    Full Text Available A novel high Performance liquid Chromatographie method was developed for the determination of 4-O-methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation. Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins. A reverse phase column of SHIM-PACK VP-ODS (150 mm × 4.6 mm, 5.0 Mm was used to separate 4-O-methylhonokiol in the plasma samples. The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear ränge was 0.012 – 1.536 μg/L. The good extraction recoveries were obtained for the spiked samples (84.7%, 89.3% and 87.7% for low, middle and high concentrations of added Standards, respectively. The relative standard deviation of intra-day and inter-day precisions was in the ränge from 0.6% to 13.5%. The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasma-concentration curve of 4-O-methylhonokiol showed a two-apartment open model. This work developed a sensitive, stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol. Keywords: 4-O-methylhonokiol, Cortex Magnoliae Officinalis, high Performance liquid chromatography, pharmacokinetic

  9. Separation and quantitation of colour pigments of chili powder (Capsicum frutescens) by high-performance liquid chromatography-diode array detection.

    Science.gov (United States)

    Cserháti, T; Forgács, E; Morais, M H; Mota, T; Ramos, A

    2000-10-27

    The performance of reversed-phase thin-layer (RP-TLC) and reversed-phase high-performance liquid chromatography (RP-HPLC) was compared for the separation and determination of the colour pigments of chili (Capsicum frutescens) powder using a wide variety of eluent systems. No separation of pigments was achieved in RP-TLC, however, it was established that tetrahydrofuran shows an unusually high solvent strength. RP-HPLC using water-methanol-acetonitrile gradient elution separated the chili pigments in many fractions. Diode array detection (DAD) indicated that yellow pigments are eluted earlier than the red ones and chili powder contains more yellow pigments than common paprika powders. It was established that the very different absorption spectra of pigments make the use of DAD necessary.

  10. Investigation of prostaglandin levels in human milk after high performance liquid chromatography purification

    International Nuclear Information System (INIS)

    Wu-Wang, C.Y.; Neu, J.

    1986-01-01

    This study was conducted to investigate five prostaglandins (PGs), i.e. PGE 2 , PGF/sub 2α/, 13-14-dihydro-15-keto-PGF/sub 2α/ (DHKF/sub 2α/), thromboxane B 2 (TXB 2 ) and 6-keto-PGF/sub 1α/), measured by (RIA) after C 18 Sep-Pak extraction and reverse phase high performance liquid chromatography (HPLC). Two trials were performed. In each trial, 3-5 mature human milk samples were pooled, acidified and extracted for PGs. The separation of PGs by HPLC was achieved by using an isocratic solvent system of acetonitrile/water (pH 3.0) (32/68, V/V). The PG levels from the two trials were determined and averaged after monitoring the recoveries. The results indicate that PGE 2 and DHKF/sub 2α/ are the two major PGs found in extracted human milk. However, after HPLC purification, no predominant PG is found and the levels of all the five PGs are much lower compared to the extracted sample. Since the immunoreactive material was also detected in HPLC fractions not within the PG peak, low levels of PG found in human milk after HPLC is likely due to the purification step removing the bulk of nonspecific immunoreactive substances present in the sample

  11. Simultaneous Analysis of Ursolic Acid and Oleanolic Acid in Guava Leaves Using QuEChERS-Based Extraction Followed by High-Performance Liquid Chromatography

    Science.gov (United States)

    Xu, Chang; Liao, Yiyi; Fang, Chunyan; Zhang, Yingxia

    2017-01-01

    In this paper, a novel method of QuEChERS-based extraction coupled with high-performance liquid chromatography has been developed for the simultaneous determination of ursolic acid (UA) and oleanolic acid (OA) in guava leaves. The QuEChERS-based extraction parameters, including the amount of added salt, vortex-assisted extraction time, and absorbent amount, and the chromatographic conditions were investigated for the analysis of UA and OA in guava leaves. Under the optimized conditions, the method showed good linearity over a range of 1–320 μg mL−1, with correlation coefficients above 0.999. The limits of detection of UA and OA were 0.18 and 0.36 μg mL−1, respectively. The intraday and interday precision were below 1.95 and 2.55%, respectively. The accuracies of the UA and OA determinations ranged from 97.4 to 111.4%. The contents of UA and OA in the guava leaf samples were 2.50 and 0.73 mg g−1, respectively. These results demonstrate that the developed method is applicable to the simultaneous determination of UA and OA in guava leaves. PMID:28781908

  12. Evaluation of Some Pesticide Residues in Fruits import by High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Lamees Munef Abdul-Latef

    2017-02-01

    Full Text Available Pesticide residues have been found in various fruits and vegetables.  This studycollected 24 samples and reported a method based on High Performance Liquid Chromatography (HPLC. For determination of pesticide residues used in Some fruits which were collected from different markets of Baghdad city to make 24 samples from (peel , core, mixture for each type of fruits markets as:  Oranges( Egypt , Africa, Pomegranate ( Egypt, Mango ( Kenya , Pears (China,  Plum fruits ( Africa , Kiwi (Turkey .That detective of ( 5 different  pesticides (diazinon,  malathion, chlorpyrifos ,parathion  and cypermethrin. The results were detected of multi-residues of  pesticides on the fruit in ( peel , core , mixture may be in the limit of Maximum residue limits(MRL or higher of it   . The pesticides detected that exceeding the limits are: cypermethrin  in Kiwi (peel, core and mixtureat(0.204,0.038, 0.537, in pomegranate detected in (peel and mixture at (0.509,0.189 mg/kg , Diazinondetccted in Egyptian orange in (peel ,core and mixture at (0.031,0.207, 0.099 mg/kg . Malathion and Parathion was not detected at any type of fruits and  that results was compared with codex of FAO/WHO(2013. That data is important to monitor residues in food and to fill gaps in current knowledge would be helpful in assessing human exposure risks from ingestion of contaminated Fruits Imported to our country .

  13. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of pesticides in water by graphitized carbon-based solid-phase extraction and high-performance liquid chromatography/mass spectrometry

    Science.gov (United States)

    Furlong, Edward T.; Anderson, Bruce D.; Werner, Stephen L.; Soliven, Paul P.; Coffey, Laura J.; Burkhardt, Mark R.

    2001-01-01

    In 1996, the U.S. Geological Survey National Water Quality Laboratory (NWQL) developed and implemented a graphitized carbon-based solid-phase extraction and high-performance liquid chromatographic analytical method to determine polar pesticide concentrations in surface- and ground-water samples. Subsequently, the NWQL developed a complementary analysis that uses high-performance liquid chromatography/mass spectrometry to detect, identify, and quantify polar pesticides and pesticide metabolites in filtered water at concentrations as low as 10 nanograms per liter. This new method was designed to improve sensitivity and selectivity over the prior method, and to reduce known interferences from natural organic matter.In this new method, pesticides are extracted from filtered water samples by useing a 0.5-gram graphitized carbon-based solid-phase extraction cartridge, eluted from the cartridge, and concentrations determined by using high-performance liquid chromatography with electrospray ionization-mass spectrometry. The upper concentration limit is 1.000 microgram per liter (μg/L) for most compounds. Single-operator method detection limits in organic-free water samples fortified with pesticides at a concentration of 0.025 μg/L ranged from 0.0019 to 0.022 μg/L for all compounds in the method. The grand mean (mean of mean recoveries for individual compounds) recoveries in organic-free water samples ranged from 72 to 89 percent, fortified with pesticides at three concentrations between 0.025 and 0.5 μg/L. Grand mean recoveries in ground- and surface-water samples ranged from 46 to 119 percent, also fortified with pesticides at three concentrations between 0.025 and 0.5 μg/L. Long-term recoveries from reagent water spikes were used to demonstrate that 38 of 65 compounds can be reported without qualification of the quantitative result across the analytical range of the method. The remaining 27 are reported with qualified estimates of concentration because of greater

  14. Determination of the Acid Dissociation Constant of a Phenolic Acid by High Performance Liquid Chromatography: An Experiment for the Upper Level Analytical Chemistry Laboratory

    Science.gov (United States)

    Raboh, Ghada

    2018-01-01

    A high performance liquid chromatography (HPLC) experiment for the upper level analytical chemistry laboratory is described. The students consider the effect of mobile-phase composition and pH on the retention times of ionizable compounds in order to determine the acid dissociation constant, K[subscript a], of a phenolic acid. Results are analyzed…

  15. Optimizing separations in online comprehensive two‐dimensional liquid chromatography

    OpenAIRE

    Pirok, Bob W.J.; Gargano, Andrea F.G.; Schoenmakers, Peter J.

    2017-01-01

    Abstract Online comprehensive two‐dimensional liquid chromatography has become an attractive option for the analysis of complex nonvolatile samples found in various fields (e.g. environmental studies, food, life, and polymer sciences). Two‐dimensional liquid chromatography complements the highly popular hyphenated systems that combine liquid chromatography with mass spectrometry. Two‐dimensional liquid chromatography is also applied to the analysis of samples that are not compatible with mass...

  16. Identification and quantification of cannabinoids in Cannabis sativa L. plants by high performance liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Aizpurua-Olaizola, Oier; Omar, Jone; Navarro, Patricia; Olivares, Maitane; Etxebarria, Nestor; Usobiaga, Aresatz

    2014-11-01

    High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) has been successfully applied to cannabis plant extracts in order to identify cannabinoid compounds after their quantitative isolation by means of supercritical fluid extraction (SFE). MS conditions were optimized by means of a central composite design (CCD) approach, and the analysis method was fully validated. Six major cannabinoids [tetrahydrocannabinolic acid (THCA), tetrahydrocannabinol (THC), cannabidiol (CBD), tetrahydrocannabivarin (THCV), cannabigerol (CBG), and cannabinol (CBN)] were quantified (RSD Cannabis sativa L. plant varieties and the principal component analysis (PCA) of the resulting data, a clear difference was observed between outdoor and indoor grown plants, which was attributed to a higher concentration of THC, CBN, and CBD in outdoor grown plants.

  17. Chemical characterization of neonicotinoids in surface waters by high performance liquid chromatography with Tandem Mass Spectrometry (HPLC MS/MS)

    International Nuclear Information System (INIS)

    Amaral, Priscila Oliveira

    2017-01-01

    The present study aimed to develop a method for the determination and validation of a method for the identification and quantification of Neonicotinoids in surface waters collected in the Bauru region, in the state of São Paulo. The analytical techniques studied for the development of this method were the high performance liquid chromatography with tandem mass spectrometry (HPLC - MS / MS), gas chromatography with mass spectrometry (GC / MS) and gas chromatography with electron capture detector (GC / ECD). The class of pesticides Neonicotinoids was chosen for this work because it is related to a sudden disappearance of bees in colonies around the world. This phenomenon is known as Colony Collapse Disorder (CCD) and it is characterized by a rapid loss in the population of adult bees. The Neonicotinoids used in this study were the compounds Clothianidin, Imidacloprid and Thiamethoxam which were banned in their use as pesticides in Europe by Implementing Regulation No. 540/2011. The samples were concentrated using solid phase extraction (SPE) and liquid liquid extraction (LLE) techniques and injected into HPLC-MS / MS, GC / MS and GC / ECD. The GC / ECD and GC / MS techniques were not satisfactory for determination in the water matrix because the detection limit (10 mg L -1 ) is above the maximum allowed by the US Environmental Protection Agency (0.6 μg L -1 ). The HPLC - MS / MS technique using the multiple reaction monitoring (MRM) proved to be adequate for this study because it obtained quantification limits between 5.89 and 8.06 μg L -1 and a linearity between 0.9963 and 0.9999 for the three compounds. (author)

  18. Determination of undecylenic and sorbic acids in cosmetic preparations by high performance liquid chromatography with electrochemical detection.

    Science.gov (United States)

    Bousquet, Ennio; Spadaro, A; Santagati, N A; Scalia, S; Ronsisvalle, G

    2002-11-07

    A highly sensitive and selective method for the determination of sorbic (SA) and undecylenic acid (UA) in cosmetic formulations by a high performance liquid chromatography method with electrochemical detection (ECD) is described. The pre-column derivatizations of SA and UA and the internal standard (cyclohexanoic acid (cHA)) were carried out using 1-(2,5-dihydroxyphenyl)-2-bromoethanone (2,5-DBE) as an electroactive labeling reagent previously synthesized in our lab. The resulting electroactive esters were separated by isocratic elution of a 5 micrometer Hypersil CN column with acetonitrile-acetate buffer eluent. The compounds were detected by a porous graphite electrode set at an oxidation potential of +0.45 V. The analytical method developed in this study is suitable for quality control assays of complex cosmetic formulations containing sorbic and/or UA.

  19. Column Liquid Chromatography.

    Science.gov (United States)

    Majors, Ronald E.; And Others

    1984-01-01

    Reviews literature covering developments of column liquid chromatography during 1982-83. Areas considered include: books and reviews; general theory; columns; instrumentation; detectors; automation and data handling; multidimensional chromatographic and column switching techniques; liquid-solid chromatography; normal bonded-phase, reversed-phase,…

  20. Fast and Simple Forensic Red Pen Ink Analysis Using Ultra-Performance Liquid Chromatography (UPLC)

    International Nuclear Information System (INIS)

    Lee, L.C.; Ying, S.L.; Wan Nur Syazwani Wan Mohamad Fuad; Ab Aziz Ishak; Khairul Osman

    2016-01-01

    Ultra-performance liquid chromatography (UPLC) is more effective than high performance liquid chromatography in terms of analysis speed and sensitivity. This paper presents a feasibility study on forensic red pen inks analysis using UPLC. A total of 12 varieties of red ball point pen inks were purchased from selected stationary shop. For each variety, four different individual pens were sampled to provide intra-variability within a particular variety of pen. The proposed approach is very simple that it only involved limited analysis step and chemicals. A total of 144 chromatograms were obtained from red ink entries extracted with 1.5 mL 80 % (v/v) acetonitrile. Peaks originated from pen inks were determined by comparing the chromatograms of both blank paper and blank solvent against that of ink samples. Subsequently, one-way ANOVA was conducted to discriminate all 66 possible pairs for red pen inks. Results showed that the proposed approach giving discriminating power of 95.45 %. The outcome of the study indicates that UPLC could be a fast and simple approach to red ball point pen inks analysis. (author)

  1. Determination of rifampicin in human plasma by high-performance liquid chromatography coupled with ultraviolet detection after automatized solid-liquid extraction.

    Science.gov (United States)

    Louveau, B; Fernandez, C; Zahr, N; Sauvageon-Martre, H; Maslanka, P; Faure, P; Mourah, S; Goldwirt, L

    2016-12-01

    A precise and accurate high-performance liquid chromatography (HPLC) quantification method of rifampicin in human plasma was developed and validated using ultraviolet detection after an automatized solid-phase extraction. The method was validated with respect to selectivity, extraction recovery, linearity, intra- and inter-day precision, accuracy, lower limit of quantification and stability. Chromatographic separation was performed on a Chromolith RP 8 column using a mixture of 0.05 m acetate buffer pH 5.7-acetonitrile (35:65, v/v) as mobile phase. The compounds were detected at a wavelength of 335 nm with a lower limit of quantification of 0.05 mg/L in human plasma. Retention times for rifampicin and 6,7-dimethyl-2,3-di(2-pyridyl) quinoxaline used as internal standard were respectively 3.77 and 4.81 min. This robust and exact method was successfully applied in routine for therapeutic drug monitoring in patients treated with rifampicin. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Quantitative Determination of Compounds from Akebia quinata by High-Performance Liquid Chromatography

    International Nuclear Information System (INIS)

    Yen, Nguyen; Thu, Nguyen; Zhao, Bing Tian; Woo, Mi Hee; Min, Byung Sun; Lee, Jae Hyun; Kim, Jeong Ah; Son, Jong Keun; Choi, Jae Sui; Woo, Eun Rhan

    2014-01-01

    To provide the scientific corroboration of the traditional uses of Akebia quinata (Thunb.) Decne., a detailed analytical examination of A. quinata stems was carried out using a reversed-phase high performance liquid chromatography (RP-HPLC) method coupled to photodiode array detector (PDA) for the simultaneous determination of four phenolic substances; cuneataside D, 2-(3,4-dihydroxyphenyl)ethyl-O-β-D-glucopyranoside, 3-caffeoylquinic acid and calceolarioside B. Particular attention was focused on the main compound, 3-caffeoylquinic acid, which has a range of biological functions. In addition, 2-(3,4-dihydroxyphenyl)ethyl-O-β-D-glucopyranoside was considered as a discernible marker of A. quinata from its easy confuse plants. The contents of compounds 2 and 3 ranged from 0.72 to 2.68 mg/g and from 1.66 to 5.64 mg/g, respectively. The validation data indicated that this HPLC/PDA assay was used successfully to quantify the four phenolic compounds in A. quinata from different locations using relatively simple conditions and procedures. The pattern-recognition analysis data from 53 samples classified them into two groups, allowing discrimination between A. quinata and comparable herbs. The results suggest that the established HPLC/PDA method is suitable for quantitation and pattern-recognition analyses for a quality evaluation of this medicinal herb

  3. Quantitative Determination of Compounds from Akebia quinata by High-Performance Liquid Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Yen, Nguyen; Thu, Nguyen; Zhao, Bing Tian; Woo, Mi Hee; Min, Byung Sun [Catholic Univ. of Daegu, Gyeongsan (Korea, Republic of); Lee, Jae Hyun [Dongguk Univ., Yongin (Korea, Republic of); Kim, Jeong Ah [Kyungpook National Univ., Daegu (Korea, Republic of); Son, Jong Keun [Yeungnam Univ., Gyeongsan (Korea, Republic of); Choi, Jae Sui [Pukyung National Univ., Busan (Korea, Republic of); Woo, Eun Rhan [Chosun Univ., Gwangju (Korea, Republic of)

    2014-07-15

    To provide the scientific corroboration of the traditional uses of Akebia quinata (Thunb.) Decne., a detailed analytical examination of A. quinata stems was carried out using a reversed-phase high performance liquid chromatography (RP-HPLC) method coupled to photodiode array detector (PDA) for the simultaneous determination of four phenolic substances; cuneataside D, 2-(3,4-dihydroxyphenyl)ethyl-O-β-D-glucopyranoside, 3-caffeoylquinic acid and calceolarioside B. Particular attention was focused on the main compound, 3-caffeoylquinic acid, which has a range of biological functions. In addition, 2-(3,4-dihydroxyphenyl)ethyl-O-β-D-glucopyranoside was considered as a discernible marker of A. quinata from its easy confuse plants. The contents of compounds 2 and 3 ranged from 0.72 to 2.68 mg/g and from 1.66 to 5.64 mg/g, respectively. The validation data indicated that this HPLC/PDA assay was used successfully to quantify the four phenolic compounds in A. quinata from different locations using relatively simple conditions and procedures. The pattern-recognition analysis data from 53 samples classified them into two groups, allowing discrimination between A. quinata and comparable herbs. The results suggest that the established HPLC/PDA method is suitable for quantitation and pattern-recognition analyses for a quality evaluation of this medicinal herb.

  4. Evaluation of graphene-based sorbent in the determination of polar environmental contaminants in water by micro-solid phase extraction-high performance liquid chromatography.

    Science.gov (United States)

    Naing, Nyi Nyi; Li, Sam Fong Yau; Lee, Hian Kee

    2016-01-04

    A facile method of extraction using porous membrane protected micro-solid phase extraction (μ-SPE) with a graphene-based sorbent followed by high performance liquid chromatography-ultraviolet detector was developed. The reduced graphene oxide (r-GO) (1mg), synthesized from graphite oxide, was enclosed in a polypropylene bag representing the μ-SPE device, which was used for the extraction of estrogens such as estrone, 17β-estradiol, 17α-ethynylestradiol and diethylstilbestrol in water. The r-GO obtained was identified and characterized by Fourier transform infrared, transmission electron microscopy, scanning electron microscopy and thermogravimetric analysis. The sorbent was loaded with sodium dodecyl sulfate by sonication to prevent agglomeration in aqueous solution. With this method, low limits of detection of between 0.24 and 0.52 ng L(-1) were achieved. For estrogen analysis a linear calibration range of 0.01-100 μg L(-1) was obtained, with the coefficients of determination (r(2)) higher than 0.992. This proposed method was successfully applied to determine estrogens in water. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Determination of vitamin K homologues by high-performance liquid chromatography with on-line photoreactor and peroxyoxalate chemiluminescence detection

    International Nuclear Information System (INIS)

    Ahmed, Sameh; Kishikawa, Naoya; Nakashima, Kenichiro; Kuroda, Naotaka

    2007-01-01

    A sensitive and highly selective high-performance liquid chromatography (HPLC) method was developed for the determination of vitamin K homologues including phylloquinone (PK), menaquinone-4 (MK-4) and menaquinone-7 (MK-7) in human plasma using post-column peroxyoxalate chemiluminescence (PO-CL) detection following on-line ultraviolet (UV) irradiation. The method was based on ultraviolet irradiation (254 nm, 15 W) of vitamin K to produce hydrogen peroxide and a fluorescent product at the same time, which can be determined with PO-CL detection. The separation of vitamin K by HPLC was accomplished isocratically on an ODS column within 35 min. The method involves the use of 2-methyl-3-pentadecyl-1,4-naphthoquinone as an internal standard. The detection limits (signal-to-noise ratio = 3) were 32, 38 and 85 fmol for PK, MK-4 and MK-7, respectively. The recoveries of PK, MK-4 and MK-7 were greater than 82% and the inter- and intra-assay R.S.D. values were 1.9-5.4%. The sensitivity and selectivity of this method were sufficient for clinical and nutritional applications

  6. Detection of anabolic and androgenic steroids and/or their esters in horse hair using ultra-high performance liquid chromatography-high resolution mass spectrometry.

    Science.gov (United States)

    Kwok, Karen Y; Choi, Timmy L S; Kwok, Wai Him; Wong, Jenny K Y; Wan, Terence S M

    2017-04-14

    Anabolic and androgenic steroids (AASs) are a class of prohibited substances banned in horseracing at all times. The common approach for controlling the misuse of AASs in equine sports is by detecting the presence of AASs and/or their metabolites in urine and blood samples using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). This approach, however, often falls short as the duration of effect for many AASs are longer than their detection time in both urine and blood. As a result, there is a high risk that such AASs could escape detection in their official race-day samples although they may have been used during the long period of training. Hair analysis, on the other hand, can afford significantly longer detection windows. In addition, the identification of synthetic ester derivatives of AASs in hair, particularly for the endogenous ones, can provide unequivocal proof of their exogenous origin. This paper describes the development of a sensitive method (at sub to low parts-per-billion or ppb levels) for detecting 48 AASs and/or their esters in horse hair using ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Decontaminated horse hair was pulverised and subjected to in-situ liquid-liquid extraction in a mixture of hexane - ethyl acetate (7:3, v/v) and phosphate buffer (0.1M, pH 9.5), followed by additional clean-up using mixed-mode solid-phase extraction. The final extract was analysed using UHPLC-HRMS in the positive electrospray ionisation (ESI) mode with both full scan and parallel reaction monitoring (PRM). This method was validated for qualitative identification purposes. Validation data, including method specificity, method sensitivity, extraction recovery, method precision and matrix effect are presented. Method applicability was demonstrated by the successful detection and confirmation of testosterone propionate in a referee hair sample. To our knowledge, this was

  7. Ultra-high performance liquid chromatography tandem high-resolution mass spectrometry study of tricyclazole photodegradation products in water.

    Science.gov (United States)

    Gosetti, Fabio; Chiuminatto, Ugo; Mazzucco, Eleonora; Mastroianni, Rita; Bolfi, Bianca; Marengo, Emilio

    2015-06-01

    This paper reports the study of the photodegradation reactions that tricyclazole can naturally undergo, under the action of sunlight, in aqueous solutions of standard tricyclazole and of the commercial BEAM(TM) formulation. The analyses are carried out by ultra-high performance liquid chromatography technique coupled with high-resolution tandem mass spectrometry. Analysis of both tricyclazole and BEAM(TM) water solutions undergone to hydrolysis does not evidence new chromatographic peaks with respect to the not treated solutions. On the contrary, analysis of the same samples subjected to sunlight irradiation shows a decreased intensity of tricyclazole signal and the presence of new chromatographic peaks. Two photodegradation products of tricyclazole have been identified, one of which has been also quantified, being the commercial standard available. The pattern is similar for the solutions of the standard fungicide and of the BEAM(TM) formulation. The results obtained from eco-toxicological tests show that toxicity of tricyclazole standard solutions is greater than that of the irradiated ones, whereas toxicity levels of all the BEAM(TM) solutions investigated (non-irradiated, irradiated, and hydrolyzed) are comparable and lower than those shown by tricyclazole standard solutions. Experiments performed in paddy water solution show that there is no difference in the degradation products formed.

  8. Determination of the Antibiotic Oxytetracycline in Commercial Milk by Solid-Phase Extraction: A High-Performance Liquid Chromatography (HPLC) Experiment for Quantitative Instrumental Analysis

    Science.gov (United States)

    Mei-Ratliff, Yuan

    2012-01-01

    Trace levels of oxytetracylcine spiked into commercial milk samples are extracted, cleaned up, and preconcentrated using a C[subscript 18] solid-phase extraction column. The extract is then analyzed by a high-performance liquid chromatography (HPLC) instrument equipped with a UV detector and a C[subscript 18] column (150 mm x 4.6 mm x 3.5 [mu]m).…

  9. Sensitive determination of melamine in milk and powdered infant formula samples by high-performance liquid chromatography using dabsyl chloride derivatization followed by dispersive liquid-liquid microextraction.

    Science.gov (United States)

    Faraji, M; Adeli, M

    2017-04-15

    A new and sensitive pre-column derivatization with dabsyl chloride followed by dispersive liquid-liquid microextraction was developed for the analysis of melamine (MEL) in raw milk and powdered infant formula samples by high performance liquid chromatography (HPLC) with visible detection. Derivatization with dabsyl chloride leads to improving sensitivity and hydrophobicity of MEL. Under optimum conditions of derivatization and microextraction steps, the method yielded a linear calibration curve ranging from 1.0 to 500μgL -1 with a determination coefficient (R 2 ) of 0.9995. Limit of detection and limit of quantification were 0.1 and 0.3μgL -1 , respectively. The relative standard deviation (RSD%) for intra-day (repeatability) and inter-day (reproducibility) at 25 and 100μgL -1 levels of MEL was less than 7.0% (n=6). Finally, the proposed method was successfully applied for the preconcentration and determination of MEL in different raw milk and powdered infant formula, and satisfactory results were obtained (relative recovery ⩾94%). Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Qualitative and quantitative two-dimensional thin-layer chromatography/high performance liquid chromatography/diode-array/electrospray-ionization-time-of-flight mass spectrometry of cholinesterase inhibitors.

    Science.gov (United States)

    Mroczek, Tomasz

    2016-09-10

    Recently launched thin-layer chromatography-mass spectrometry (TLC-MS) interface enabling extraction of compounds directly from TLC plates into MS ion source was unusually extended into two-dimensional thin-layer chromatography/high performance liquid chromatography (2D, TLC/HPLC) system by its a direct connection to a rapid resolution 50×2.1mm, I.D. C18 column compartment followed by detection by diode array (DAD) and electrospray ionisation time-of-flight mass spectrometry (ESI-TOF-MS). In this way, even not separated bands of complicated mixtures of natural compounds could be analysed structurally, only within 1-2min after development of TLC plates. In comparison to typically applied TLC-MS interface, no ion suppression for acidic mobile phases was observed. Also, substantial increase in ESI-TOF-MS sensitivities and quality of spectra, were noticed. It has been utilised in combination with TLC- based bioautographic approaches of acetylcholinesterase (AChE) inhibitors, However, it can be also applied in any other procedures related to bioactivity (e.g. 2,2-Diphenyl-1-picryl-hydrazyl-DPPH screen test for radicals). This system has been also used for determination of half maximal inhibitory concentration (IC50 values) of the active inhibitor-galanthamine, as an example. Moreover, AChE inhibitory potencies of some of purified plant extracts, never studied before, have been quantitatively measured. This is first report of usage such the 2D TLC/HPLC/MS system both for qualitative and quantitative evaluation of cholinesterase inhibitors in biological matrices. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Simultaneous determination of amiodarone and its metabolite desethylamiodarone by high-performance liquid chromatography with chemiluminescent detection

    International Nuclear Information System (INIS)

    Perez-Ruiz, Tomas; Martinez-Lozano, Carmen; Garcia-Martinez, Maria Dolores

    2008-01-01

    A novel method was developed for the determination of amiodarone and desethylamiodarone by high-performance liquid chromatography (HPLC) coupled with chemiluminescent (CL) detection. The procedure is based on the post-column photolysis of the analytes into photoproducts which are active in the tris(2,2'-bipyridyl)ruthenium(III) [Ru(bpy) 3 3+ ] CL system. Ru(bpy) 3 3+ was on-line generated by photo-oxidation of the Ru(II) complex in the presence of peroxydisulfate. The separation was carried out on a Mediterranea C 18 column with isocratic elution using a mixture of methanol and 0.017 mol L -1 ammonium sulfate buffer of pH 6.8. Under the optimum conditions, analytical curves, based on standard solutions, were linear over the range 0.1-50 μg mL -1 for amiodarone and 0.5-25 μg mL -1 for desethylamiodarone. The detection limits of amiodarone and desethylamiodarone were 0.02 and 0.11 μg mL -1 , respectively. Intra- and inter-day precision values of 0.9% relative standard deviation (R.S.D.) (n = 10) and 1.6% R.S.D. (n = 15), respectively, were obtained. The method was applied successfully to the determination of these compounds in serum and pharmaceutical formulations

  12. Cobalamin speciation using reversed-phase micro-high-performance liquid chromatography interfaced to inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Yanes, Enrique G.; Miller-Ihli, Nancy J.

    2004-01-01

    Micro-high-performance liquid chromatography interfaced to inductively coupled plasma mass spectrometry was optimized for the determination and separation of a mixture of cobalt containing species. Four cobalamin species (cyanocobalamin, hydroxocobalamin, methylcobalamin, and 5'-deoxyadenosylcobalamin) representing the various forms of vitamin B12 as well as the harmful corrinoid analogue cobinamide dicyanide were separated using reversed-phase microcapillary chromatography with columns containing C18 packing material with a 2-μm particle size. Selection of organic solvents for the separation took into consideration compatibility with the inductively coupled plasma mass spectrometer being used for element specific detection. Optimized method conditions included use of a methanol gradient and make-up solution for the nebulizer. Some issues associated with dead volume were overcome by the extension of the gradient program. The total analysis time was 52 min. The column-to-column variability was evaluated and was found to be very reasonable (9% RSD on average), confirming that this method is rugged and that the technology should be easily transferred to other laboratories

  13. Classification of the medicinal plants of the genus Atractylodes using high-performance liquid chromatography with diode array and tandem mass spectrometry detection combined with multivariate statistical analysis.

    Science.gov (United States)

    Cho, Hyun-Deok; Kim, Unyong; Suh, Joon Hyuk; Eom, Han Young; Kim, Junghyun; Lee, Seul Gi; Choi, Yong Seok; Han, Sang Beom

    2016-04-01

    Analytical methods using high-performance liquid chromatography with diode array and tandem mass spectrometry detection were developed for the discrimination of the rhizomes of four Atractylodes medicinal plants: A. japonica, A. macrocephala, A. chinensis, and A. lancea. A quantitative study was performed, selecting five bioactive components, including atractylenolide I, II, III, eudesma-4(14),7(11)-dien-8-one and atractylodin, on twenty-six Atractylodes samples of various origins. Sample extraction was optimized to sonication with 80% methanol for 40 min at room temperature. High-performance liquid chromatography with diode array detection was established using a C18 column with a water/acetonitrile gradient system at a flow rate of 1.0 mL/min, and the detection wavelength was set at 236 nm. Liquid chromatography with tandem mass spectrometry was applied to certify the reliability of the quantitative results. The developed methods were validated by ensuring specificity, linearity, limit of quantification, accuracy, precision, recovery, robustness, and stability. Results showed that cangzhu contained higher amounts of atractylenolide I and atractylodin than baizhu, and especially atractylodin contents showed the greatest variation between baizhu and cangzhu. Multivariate statistical analysis, such as principal component analysis and hierarchical cluster analysis, were also employed for further classification of the Atractylodes plants. The established method was suitable for quality control of the Atractylodes plants. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. High performance liquid chromatography method for the determination of cinnamyl alcohol dehydrogenase activity in soybean roots.

    Science.gov (United States)

    dos Santos, W D; Ferrarese, Maria de Lourdes Lucio; Ferrarese-Filho, O

    2006-01-01

    This study proposes a simple, quick and reliable method for determining the cinnamyl alcohol dehydrogenase (CAD; EC 1.1.1.195) activity in soybean (Glycine max L. Merr.) roots using reversed-phase high performance liquid chromatography (RP-HPLC). The method includes a single extraction of the tissue and conduction of the enzymatic reaction at 30 degrees C with cinnamaldehydes (coniferyl or sinapyl), substrates of CAD. Disappearance of the substrates in the reaction mixture is monitored at 340 nm (for coniferaldehyde) or 345 nm (for sinapaldehyde) by isocratic elution with methanol/acetic acid through a GLC-ODS (M) column. This HPLC technique furnishes a rapid and reliable measure of cinnamaldehyde substrates, and may be used as an alternative tool to analyze CAD activity in enzyme preparation without previous purification.

  15. Complete separation of racemic p-boronophenylalanine by high performance liquid chromatography with crown ether-coated reversed-phase packings

    International Nuclear Information System (INIS)

    Yoshino, K.; Mieda, S.; Maruyama, T.; Mori, Y.; Mishima, Y.; Ichihashi, M.

    1992-01-01

    Since the L-form of p-boronophenylalanine (p-bpa) has been shown to be more efficiently incorporated into melanoma cells than racemic p-bpa separation of racemic p-bpa into its stereoisomers is an important subject. One of the preparative methods used to resolve racemic p-bpa involves the use of α-chymotrypsin. However, there has been a problem in that optical purity of resolved L- or D-p-bpa products was not easily determined. In this paper, the authors describe a method which can be used to confirm the optical purity of b-pba using high performance liquid chromatography (HPLC) with crown ether-coated reversed-phase packings

  16. High performance liquid chromatography--atomic fluorescence spectrometric determination of arsenic species in beer samples

    International Nuclear Information System (INIS)

    Melo Coelho, N.M.; Parrilla, Carmen; Cervera, M.L.; Pastor, A.; Guardia, M. de la

    2003-01-01

    A method has been developed for the direct determination of As(III), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA) and As(V) in beers by hydride generation--atomic fluorescence spectrometry after separation of arsenic species by high performance liquid chromatography. Compounds were separated by anion-exchange chromatography with isocratic elution using KH 2 PO 4 /K 2 HPO 4 as mobile phase with elution times of 1.67, 2.08, 6.52 and 10.72 min for As(III), DMA, MMA and As(V), respectively. Parameters affecting the hydride generation of all arsenic species were studied and the best conditions were established as a reaction coil of 150 cm, for a sample injected volume of 100 μl, a 4.0% (m/v) solution of sodium tetrahydroborate and 2.0 mol l -1 hydrochloric acid with flow rates of 2.7 and 1.7 ml min -1 , respectively and a flow rate of 500 ml min -1 for the argon carrier gas. Under the best experimental conditions, the detection limit was found to be 0.12, 0.20, 0.27 and 0.39 μg l -1 for As(III), DMA, MMA and As(V), respectively. The relative standard deviation for eight independent determinations varied from 3.9 till 8.9% for species considered at a concentration level of 10.0 μg l -1 . Recovery and comparative studies evidenced that the method is suitable for the accurate determination of arsenic species in water and beer samples

  17. Validation of high-performance liquid chromatography (HPLC method for quantitative analysis of histamine in fish and fishery products

    Directory of Open Access Journals (Sweden)

    B.K.K.K. Jinadasa

    2016-12-01

    Full Text Available A high-performance liquid chromatography method is described for quantitative determination and validation of histamine in fish and fishery product samples. Histamine is extracted from fish/fishery products by homogenizing with tri-chloro acetic acid, separated with Amberlite CG-50 resin and C18-ODS Hypersil reversed phase column at ambient temperature (25°C. Linear standard curves with high correlation coefficients were obtained. An isocratic elution program was used; the total elution time was 10 min. The method was validated by assessing the following aspects; specificity, repeatability, reproducibility, linearity, recovery, limits of detection, limit of quantification and uncertainty. The validated parameters are in good agreement with method and it is a useful tool for determining histamine in fish and fishery products.

  18. Application of High-Performance Liquid Chromatography Coupled with Linear Ion Trap Quadrupole Orbitrap Mass Spectrometry for Qualitative and Quantitative Assessment of Shejin-Liyan Granule Supplements

    OpenAIRE

    Jifeng Gu; Weijun Wu; Mengwei Huang; Fen Long; Xinhua Liu; Yizhun Zhu

    2018-01-01

    A method for high-performance liquid chromatography coupled with linear ion trap quadrupole Orbitrap high-resolution mass spectrometry (HPLC-LTQ-Orbitrap MS) was developed and validated for the qualitative and quantitative assessment of Shejin-liyan Granule. According to the fragmentation mechanism and high-resolution MS data, 54 compounds, including fourteen isoflavones, eleven ligands, eight flavonoids, six physalins, six organic acids, four triterpenoid saponins, two xanthones, two alkaloi...

  19. Simultaneous determination of six synthetic phenolic antioxidants in edible oils using dispersive liquid-liquid microextraction followed by high-performance liquid chromatography with diode array detection.

    Science.gov (United States)

    Xu, Shuangjiao; Liu, Liangliang; Wang, Yanqin; Zhou, Dayun; Kuang, Meng; Fang, Dan; Yang, Weihua; Wei, Shoujun; Xiao, Aiping; Ma, Lei

    2016-08-01

    A simple, rapid, organic-solvent- and sample-saving pretreatment technique, called dispersive liquid-liquid microextraction, was developed for the determination of six synthetic phenolic antioxidants from edible oils before high-performance liquid chromatography with diode array detection. The entire procedure was composed of a two-step microextraction and a centrifugal process and could be finished in about 5 min, only consuming only 25 mg of sample and 1 mL of the organic solvent for each extraction. The influences of several important parameters on the microextraction efficiency were thoroughly investigated. Recovery assays for oil samples were spiked at three concentration levels, 50, 100 and 200 mg/kg, and provided recoveries in the 86.3-102.5% range with a relative standard deviation below 3.5%. The intra-day and inter-day precisions for the analysis were less than 3.8%. The proposed method was successfully applied for the determination of synthetic phenolic antioxidants in different oil samples, and satisfactory results were obtained. Thus, the developed method represents a viable alternative for the quality control of synthetic phenolic antioxidant concentrations in edible oils. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Reinaldo C. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil)], E-mail: rccampos@puc-rio.br; Goncalves, Rodrigo A.; Brandao, Geisamanda P.; Azevedo, Marlo S. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil); Oliveira, Fabiana; Wasserman, Julio [Institut of Geosciences, Fluminense Federal University, Av. Gal. Milton Tavares de Souza, s/n, 24.210-340, Niteroi, Rio de Janeiro (Brazil)

    2009-06-15

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C{sub 18} column was used as stationary phase, and post column treatment was performed by UV irradiation (60 deg. C, 13 W). The eluate was then merged with 3 mol L{sup -1} HCl, reduction was performed by a NaBH{sub 4} solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 {mu}g L{sup -1} were obtained for ionic (Hg{sup 2+}) and HgCH{sub 3}{sup +}, for an injection volume of 200 {mu}L. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sedi0011men.

  1. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    International Nuclear Information System (INIS)

    Campos, Reinaldo C.; Goncalves, Rodrigo A.; Brandao, Geisamanda P.; Azevedo, Marlo S.; Oliveira, Fabiana; Wasserman, Julio

    2009-01-01

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C 18 column was used as stationary phase, and post column treatment was performed by UV irradiation (60 deg. C, 13 W). The eluate was then merged with 3 mol L -1 HCl, reduction was performed by a NaBH 4 solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 μg L -1 were obtained for ionic (Hg 2+ ) and HgCH 3 + , for an injection volume of 200 μL. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sediments.

  2. Simultaneous Determination of Ten Constituents in Chaiqin Qingning Capsule by High-performance Liquid Chromatography Coupled with Triple-quadrupole Mass Spectrometry.

    Science.gov (United States)

    Li, Ting Yu; Huo, Xiao Kui; Zheng, Lu; Wang, Chao; Cong, Hai Jian; Xiang, Ting; Zhang, Lin; Zhang, Bao Jing; Huang, Shan Shan; Wu, Bin; Li, Xin Yu

    2017-01-01

    Chaiqin Qingning Capsule (CQQNC) was a prescription of Traditional Chinese Medicine with the effects of clearing away heat and removing toxin, harmonizing the exterior and interior, it was widely used in Asian, for example, China and Japan, different batches of the raws materials and different processing time may be the vital factor which raised a challenge to control the quality of the CQQNC. In this experiment, a high-performance liquid chromatography-mass spectrometry/MS (HPLC-MS/MS) method was developed to simultaneously determine ten bioactive components for the quality control of CQQNC. Chromatographic separation was achieved using an XBridge BEH C18 column (150 mm × 4.6 mm, 2.5 μm) with a mobile phase composed of 10 mm aqueous ammonium acetate and acetonitrile using a gradient elution in 20 min. This study was conducted by multiple reaction monitoring mode through electrospray ionization resource with a negative ionization mode. The established method was validated with good performance of precision, accuracy, stability, and reproducibility and was utilized to simultaneously quantify ten constituents of CQQNC obtained from seven different batches. It is the first time to report the rapid and simultaneous analysis of the ten compounds in CQQNC by HPLC-MS/MS and apply to determine 10 constituents in 7 batches of CQQNC bought from drug store in china. This method could be considered as good quality criteria to control the quality of CQQNC. In this paper, a simple, specific, and rapid high-performance liquid chromatogram coupled with triple-quadrupole mass spectrometry method for simultaneous quantification of ten constituents in Chaiqin Qingning Capsule has been developed for the first time. This method could be considered as good quality criteria to control the quality of CQQNC. Abbreviations used: CHM: Chinese herbal medicine; TCM: Traditional Chinese Medicine; CQQNC: Triple-quadrupole mass spectrometry Chaiqin Qingning Capsules; HPLC-MS/MS: High liquid

  3. Simultaneous Determination of Ten Constituents in Chaiqin Qingning Capsule by High-performance Liquid Chromatography Coupled with Triple-quadrupole Mass Spectrometry

    Science.gov (United States)

    Li, Ting Yu; Huo, Xiao Kui; Zheng, Lu; Wang, Chao; Cong, Hai Jian; Xiang, Ting; Zhang, Lin; Zhang, Bao Jing; Huang, Shan Shan; Wu, Bin; Li, Xin Yu

    2017-01-01

    Background: Chaiqin Qingning Capsule (CQQNC) was a prescription of Traditional Chinese Medicine with the effects of clearing away heat and removing toxin, harmonizing the exterior and interior, it was widely used in Asian, for example, China and Japan, different batches of the raws materials and different processing time may be the vital factor which raised a challenge to control the quality of the CQQNC. Experimental Methods: In this experiment, a high-performance liquid chromatography-mass spectrometry/MS (HPLC-MS/MS) method was developed to simultaneously determine ten bioactive components for the quality control of CQQNC. Chromatographic separation was achieved using an XBridge BEH C18 column (150 mm × 4.6 mm, 2.5 μm) with a mobile phase composed of 10 mm aqueous ammonium acetate and acetonitrile using a gradient elution in 20 min. This study was conducted by multiple reaction monitoring mode through electrospray ionization resource with a negative ionization mode. Results: The established method was validated with good performance of precision, accuracy, stability, and reproducibility and was utilized to simultaneously quantify ten constituents of CQQNC obtained from seven different batches. Conclusion: It is the first time to report the rapid and simultaneous analysis of the ten compounds in CQQNC by HPLC-MS/MS and apply to determine 10 constituents in 7 batches of CQQNC bought from drug store in china. This method could be considered as good quality criteria to control the quality of CQQNC. SUMMARY In this paper, a simple, specific, and rapid high-performance liquid chromatogram coupled with triple-quadrupole mass spectrometry method for simultaneous quantification of ten constituents in Chaiqin Qingning Capsule has been developed for the first time. This method could be considered as good quality criteria to control the quality of CQQNC. Abbreviations used: CHM: Chinese herbal medicine; TCM: Traditional Chinese Medicine; CQQNC: Triple-quadrupole mass

  4. Fingerprint analysis of Resina Draconis by ultra-performance liquid chromatography

    OpenAIRE

    Xue, Yudi; Zhu, Lin; Yi, Tao

    2017-01-01

    Background Resina Draconis, a bright red resin derived from Dracaena cochinchinensis, is a traditional medicine used in China. To improve its quality control approach, an ultra-performance liquid chromatography (UPLC) fingerprint method was developed for rapidly evaluating the quality of Resina Draconis. Methods The precision, repeatability and stability of the proposed UPLC method were validated in the study. Twelve batches of Resina Draconis samples from various sources were analyzed by the...

  5. Evaluation of phenolic compounds in virgin olive oil by direct injection in high-performance liquid chromatography with fluorometric detection.

    Science.gov (United States)

    Selvaggini, Roberto; Servili, Maurizio; Urbani, Stefania; Esposto, Sonia; Taticchi, Agnese; Montedoro, GianFrancesco

    2006-04-19

    Hydrophilic phenols are the most abundant natural antioxidants of virgin olive oil (VOO), in which tocopherols and carotenes are also present. The prevalent classes of hydrophilic phenols found in VOO are phenyl alcohols, phenolic acids, secoiridoids such as the dialdehydic form of decarboxymethyl elenolic acid linked to (3,4-dihydroxyphenyl)ethanol or (p-hydroxypheny1)ethanol (3,4-DHPEA-EDA or p-HPEA-EDA) and an isomer of the oleuropein aglycon (3,4-DHPEA-EA), lignans such as (+)-1-acetoxypinoresinol and (+)-pinoresinol, and flavonoids. A new method for the analysis of VOO hydrophilic phenols by direct injection in high-performance liquid chromatography (HPLC) with the use of a fluorescence detector (FLD) has been proposed and compared with the traditional liquid-liquid extraction technique followed by the HPLC analysis utilizing a diode array detector (DAD) and a FLD. Results show that the most important classes of phenolic compounds occurring in VOO can be evaluated using HPLC direct injection. The efficiency of the new method, as compared to the liquid-liquid extraction, was higher to quantify phenyl alcohols, lignans, and 3,4-DHPEA-EA and lower for the evaluation of 3,4-DHPEA-EDA and p-HPEA-EDA.

  6. Determination of Cinchona alkaloids and Vitamin B6 by high-performance liquid chromatography with fluorescence detection

    International Nuclear Information System (INIS)

    Gatti, R.; Gioia, M.G.; Cavrini, V.

    2004-01-01

    A simple and specific method has been developed for the simultaneous determination of the four major Cinchona alkaloids and their dihydroderivatives and pyridoxine hydrochloride (Vitamin B 6 ) by high-performance liquid chromatography (HPLC) with fluorescence detection (λ em =420 nm with λ ex =330 nm). The chromatographic separation was performed on a Phenomenex Prodigy ODS column (5 μm, 250 mmx3.2 mm i.d.), recommended for basic compounds, under isocratic reversed-phase conditions. The method allowed a good peak shape and an effective resolution of the tested compounds. The extraction of alkaloids from the Cinchona succirubra bark was carried out in mild and fast conditions (ambient temperature, 20 min) by ultrasonication. The procedure showed to be advantageous respect to a reference method, which involved Soxhlet extraction. The results were compared statistically by means of the Student's t-test and the variance ratio F-test; no significant difference was found. The method was reproducible (relative standard deviations in the range of 1.0-5.0% for the different alkaloids) and gave quantitative recovery of alkaloids added to bark samples (97.8-105%). For additional informations a photoreactor was arranged between the analytical column and the detector and the online post-column photochemical conversion (irradiation=254 nm) was investigated. Vitamin B 6 was shown to be highly photosensitive, giving significantly different fluorescence spectra with and without UV irradiation. The proposed method was successfully applied to the quality control of Cinchona bark, liquid extract and cosmetics

  7. Multi-component determination and chemometric analysis of Paris polyphylla by ultra high performance liquid chromatography with photodiode array detection.

    Science.gov (United States)

    Chen, Pei; Jin, Hong-Yu; Sun, Lei; Ma, Shuang-Cheng

    2016-09-01

    Multi-source analysis of traditional Chinese medicine is key to ensuring its safety and efficacy. Compared with traditional experimental differentiation, chemometric analysis is a simpler strategy to identify traditional Chinese medicines. Multi-component analysis plays an increasingly vital role in the quality control of traditional Chinese medicines. A novel strategy, based on chemometric analysis and quantitative analysis of multiple components, was proposed to easily and effectively control the quality of traditional Chinese medicines such as Chonglou. Ultra high performance liquid chromatography was more convenient and efficient. Five species of Chonglou were distinguished by chemometric analysis and nine saponins, including Chonglou saponins I, II, V, VI, VII, D, and H, as well as dioscin and gracillin, were determined in 18 min. The method is feasible and credible, and enables to improve quality control of traditional Chinese medicines and natural products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. High performance liquid chromatography of substituted aromatics with the metal-organic framework MIL-100(Fe): Mechanism analysis and model-based prediction.

    Science.gov (United States)

    Qin, Weiwei; Silvestre, Martin Eduardo; Li, Yongli; Franzreb, Matthias

    2016-02-05

    Metal-organic framework (MOF) MIL-100(Fe) with well-defined thickness was homogenously coated onto the outer surface of magnetic microparticles via a liquid-phase epitaxy method. The as-synthesized MIL-100(Fe) was used as stationary phase for high-performance liquid chromatography (HPLC) and separations of two groups of mixed aromatic hydrocarbons (toluene, styrene and p-xylene; acetanilide, 2-nirtoaniline and 1-naphthylamine) using methanol/water as mobile phase were performed to evaluate its performance. Increasing water content of the mobile phase composition can greatly improve the separations on the expense of a longer elution time. Stepwise elution significantly shortens the elution time of acetanilide, 2-nirtoaniline and 1-naphthylamine mixtures, while still achieving a baseline separation. Combining the experimental results and in-depth modeling using a recently developed chromatographic software (ChromX), adsorption equilibrium parameters, including the affinities and maximum capacities, for each analyte toward the MIL-100(Fe) are obtained. In addition, the pore diffusivity of aromatic hydrocarbons within MIL-100(Fe) was determined to be 5×10(-12)m(2)s(-1). While the affinities of MIL-100(Fe) toward the analyte molecules differs much, the maximum capacities of the analytes are in a narrow range with q*MOFmax,toluene=3.55molL(-1), q*MOFmax,styrene or p-xylene=3.53molL(-1), and q*MOFmax,anilines=3.12molL(-1) corresponding to approximately 842 toluene and 838 styrene or p-xylene, and 740 aniline molecules per MIL-100(Fe) unit cell, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Clinical applications of fast liquid chromatography: a review on the analysis of cardiovascular drugs and their metabolites.

    Science.gov (United States)

    Baranowska, Irena; Magiera, Sylwia; Baranowski, Jacek

    2013-05-15

    One of the major challenges facing the medicine today is developing new therapies that enhance human health. To help address these challenges the utilization of analytical technologies and high-throughput automated platforms has been employed; in order to perform more experiments in a shorter time frame with increased data quality. In the last decade various analytical strategies have been established to enhance separation speed and efficiency in liquid chromatography applications. Liquid chromatography is an increasingly important tool for monitoring drugs and their metabolites. Furthermore, liquid chromatography has played an important role in pharmacokinetics and metabolism studies at these drug development stages since its introduction. This paper provides an overview of current trends in fast chromatography for the analysis of cardiovascular drugs and their metabolites in clinical applications. Current trends in fast liquid chromatographic separations involve monolith technologies, fused-core columns, high-temperature liquid chromatography (HTLC) and ultra-high performance liquid chromatography (UHPLC). The high specificity in combination with high sensitivity makes it an attractive complementary method to traditional methodology used for routine applications. The practical aspects of, recent developments in and the present status of fast chromatography for the analysis of biological fluids for therapeutic drug and metabolite monitoring, pharmacokinetic studies and bioequivalence studies are presented. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Quantitative Analysis of Tetramethylenedisulfotetramine ("Tetramine") Spiked into Beverages by Liquid Chromatography Tandem Mass Spectrometry with Validation by Gas Chromatography Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Owens, J; Hok, S; Alcaraz, A; Koester, C

    2008-11-13

    Tetramethylenedisulfotetramine, commonly known as tetramine, is a highly neurotoxic rodenticide (human oral LD{sub 50} = 0.1 mg/kg) used in hundreds of deliberate food poisoning events in China. Here we describe a method for quantitation of tetramine spiked into beverages, including milk, juice, tea, cola, and water and cleaned up by C8 solid phase extraction and liquid-liquid extraction. Quantitation by high performance liquid chromatography tandem mass spectrometry (LC/MS/MS) was based upon fragmentation of m/z 347 to m/z 268. The method was validated by gas chromatography mass spectrometry (GC/MS) operated in SIM mode for ions m/z 212, 240, and 360. The limit of quantitation was 0.10 {micro}g/mL by LC/MS/MS versus 0.15 {micro}g/mL for GC/MS. Fortifications of the beverages at 2.5 {micro}g/mL and 0.25 {micro}g/mL were recovered ranging from 73-128% by liquid-liquid extraction for GC/MS analysis, 13-96% by SPE and 10-101% by liquid-liquid extraction for LC/MS/MS analysis.

  11. Quantitative Analysis of Tetramethylenedisulfotetramine ('Tetramine') Spiked into Beverages by Liquid Chromatography Tandem Mass Spectrometry with Validation by Gas Chromatography Mass Spectrometry

    International Nuclear Information System (INIS)

    Owens, J.; Hok, S.; Alcaraz, A.; Koester, C.

    2008-01-01

    Tetramethylenedisulfotetramine, commonly known as tetramine, is a highly neurotoxic rodenticide (human oral LD 50 = 0.1 mg/kg) used in hundreds of deliberate food poisoning events in China. Here we describe a method for quantitation of tetramine spiked into beverages, including milk, juice, tea, cola, and water and cleaned up by C8 solid phase extraction and liquid-liquid extraction. Quantitation by high performance liquid chromatography tandem mass spectrometry (LC/MS/MS) was based upon fragmentation of m/z 347 to m/z 268. The method was validated by gas chromatography mass spectrometry (GC/MS) operated in SIM mode for ions m/z 212, 240, and 360. The limit of quantitation was 0.10 (micro)g/mL by LC/MS/MS versus 0.15 (micro)g/mL for GC/MS. Fortifications of the beverages at 2.5 (micro)g/mL and 0.25 (micro)g/mL were recovered ranging from 73-128% by liquid-liquid extraction for GC/MS analysis, 13-96% by SPE and 10-101% by liquid-liquid extraction for LC/MS/MS analysis.

  12. Prototyping of thermoplastic microfluidic chips and their application in high-performance liquid chromatography separations of small molecules.

    Science.gov (United States)

    Wouters, Sam; De Vos, Jelle; Dores-Sousa, José Luís; Wouters, Bert; Desmet, Gert; Eeltink, Sebastiaan

    2017-11-10

    The present paper discusses practical aspects of prototyping of microfluidic chips using cyclic olefin copolymer as substrate and the application in high-performance liquid chromatography. The developed chips feature a 60mm long straight separation channel with circular cross section (500μm i.d.) that was created using a micromilling robot. To irreversibly seal the top and bottom chip substrates, a solvent-vapor-assisted bonding approach was optimized, allowing to approximate the ideal circular channel geometry. Four different approaches to establish the micro-to-macro interface were pursued. The average burst pressure of the microfluidic chips in combination with an encasing holder was established at 38MPa and the maximum burst pressure was 47MPa, which is believed to be the highest ever report for these polymer-based microfluidic chips. Porous polymer monolithic frits were synthesized in-situ via UV-initiated polymerization and their locations were spatially controlled by the application of a photomask. Next, high-pressure slurry packing was performed to introduce 3μm silica reversed-phase particles as the stationary phase in the separation channel. Finally, the application of the chip technology is demonstrated for the separation of alkyl phenones in gradient mode yielding baseline peak widths of 6s by applying a steep gradient of 1.8min at a flow rate of 10μL/min. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. ICSH recommendations for assessing automated high-performance liquid chromatography and capillary electrophoresis equipment for the quantitation of HbA2.

    Science.gov (United States)

    Stephens, A D; Colah, R; Fucharoen, S; Hoyer, J; Keren, D; McFarlane, A; Perrett, D; Wild, B J

    2015-10-01

    Automated high performance liquid chromatography and Capillary electrophoresis are used to quantitate the proportion of Hemoglobin A2 (HbA2 ) in blood samples order to enable screening and diagnosis of carriers of β-thalassemia. Since there is only a very small difference in HbA2 levels between people who are carriers and people who are not carriers such analyses need to be both precise and accurate. This paper examines the different parameters of such equipment and discusses how they should be assessed. © 2015 John Wiley & Sons Ltd.

  14. Optimizing separations in online comprehensive two‐dimensional liquid chromatography

    Science.gov (United States)

    Gargano, Andrea F.G.; Schoenmakers, Peter J.

    2017-01-01

    Abstract Online comprehensive two‐dimensional liquid chromatography has become an attractive option for the analysis of complex nonvolatile samples found in various fields (e.g. environmental studies, food, life, and polymer sciences). Two‐dimensional liquid chromatography complements the highly popular hyphenated systems that combine liquid chromatography with mass spectrometry. Two‐dimensional liquid chromatography is also applied to the analysis of samples that are not compatible with mass spectrometry (e.g. high‐molecular‐weight polymers), providing important information on the distribution of the sample components along chemical dimensions (molecular weight, charge, lipophilicity, stereochemistry, etc.). Also, in comparison with conventional one‐dimensional liquid chromatography, two‐dimensional liquid chromatography provides a greater separation power (peak capacity). Because of the additional selectivity and higher peak capacity, the combination of two‐dimensional liquid chromatography with mass spectrometry allows for simpler mixtures of compounds to be introduced in the ion source at any given time, improving quantitative analysis by reducing matrix effects. In this review, we summarize the rationale and principles of two‐dimensional liquid chromatography experiments, describe advantages and disadvantages of combining different selectivities and discuss strategies to improve the quality of two‐dimensional liquid chromatography separations. PMID:29027363

  15. Fases estacionárias quirais para cromatografia líquida de alta eficiência Chiral stationary phases for high-performance liquid chromatography

    OpenAIRE

    Tiago de Campos Lourenço; Neila Maria Cassiano; Quezia B. Cass

    2010-01-01

    The development of Chiral Stationary Phases (CSPs) for high performance liquid chromatography has been studied by various researches around the world, especially, since 1980. This simple interest has been transformed into a tool of great technological value for the industrial community and scholars in general providing the existence of several CSPs, which act through different mechanisms of chiral discrimination. This paper describes the main types of CSPs that are used for the resolution of ...

  16. High performance liquid-level sensor based on mPOFBG for aircraft applications

    DEFF Research Database (Denmark)

    Marques, C. A. F.; Pospori, A.; Saez-Rodriguez, D.

    2015-01-01

    A high performance liquid-level sensor based on microstructured polymer optical fiber Bragg grating (mPOFBG) array sensors is reported in detail. The sensor sensitivity is found to be 98pm/cm of liquid, enhanced by more than a factor of 9 compared to a reported silica fiber-based sensor....

  17. Arsenic speciation in soil using high performance liquid chromatography/inductively coupled plasma/mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bass, D.A.; Yaeger, J.S.; Parish, K.J.; Crain, J.S.; Kiely, J.T.; Gowdy, M.J. [Argonne National Lab., IL (United States); Mohrman, G.B.; Besmer, M.G. [Rocky Mountain Arsenal, Commerce City, CO (United States)

    1996-08-01

    A method has been developed to identify and quantify As(III), As(V), and organoarsenic compounds in soil samples from the Rocky Mountain Arsenal (RMA) by high performance liquid chromatography/inductively coupled plasma/mass spectrometry (HPLC/ICP/MS). The soils were extracted using tetrabutylammonium hydroxide (TBAH) and sonication. The percentages of As(III), As(V), and organoarsenic species extracted from soil samples were 30, 50, and 100 respectively. The arsenic species were not altered during the extraction process. They were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. The HPLC column effluent was introduced into an ICP/MS system using a direct injection nebulizer (DIN). Detection limits of less than 1 pg were readily obtained for each arsenic species. Internal standards are recommended to increase accuracy and precision. Soil samples spiked with arsenic oxide, sodium arsenate, dimethylarsinic acid (DMAA), and chlorovinyl arsenious acid (CVAA) were extracted, identified and quantified with the HPLC/ICP/MS system. The soil samples were analyzed in support of the analytical needs of a thermal desorption treatability study being conducted at the RMA.

  18. [Determination of lutein in infant formula milk powder using ultra-high performance liquid chromatography].

    Science.gov (United States)

    Wang, Lin; Huang, Junrong; Zhang, Li; Feng, Feng; Ling, Yun; Chu, Xiaogang; Li, Hongliang

    2013-12-01

    An ultra-high performance liquid chromatography (U-HPLC) method for the determination of lutein in the infant formula milk powder was developed. The sample was extracted with acetone and defatted using freezing centrifugation method. The U-HPLC separation was achieved using a YMC Carotenoid C30 column (150 mm x 4.6 mm, 3 microm) with the mixture of methanol/methyl tert-butyl ether (70: 30, v/v) as the mobile phase under isocratic elution. The flow rate was 0.5 mL/min and the column oven temperature was 25 degrees C. The injection volume was 5 microL. It was detected on a photodiode array detector at a wavelength of 445 nm. The results showed that the linear range was 20-500 microg/L (r = 0.9999), and the limit of quantification was 20 microg/L. The mean recoveries of lutein varied from 97.9% to 104.4% spiked at 50, 250 and 2,000 microg/kg. The established method is simple, accurate and sensitive for the rapid determination of lutein in infant formula milk powder.

  19. Determination of periplocymarin in human blood and urine by high-performance liquid chromatography-mass spectrometry

    Directory of Open Access Journals (Sweden)

    Chen Jian Xia

    2017-01-01

    Full Text Available A simple, rapid and sensitive liquid chromatography with tandem mass spectrometry method for the determination of periplocymarin in human blood and urine was developed. The digoxin-d3 was used as an internal standard. Periplocymarin and digoxin-d3 (IS were processed with ethyl acetate by liquid-liquid extraction. The chromatographic separation was performed on a Shim-pack XR-ODSIII C18 column with a 7 min gradient elution using methanol-ammonium formate (5 mmol/L as mobile phase at a flow rate of 0.3 mL/min (65:35, v/v. The detection was performed on a triple quadrupole tandem mass spectrometer using positive-ion mode electrospray ionization in selected reaction monitoring mode. The periplocymarin was well separated from the internal standard. Two calibration curves were linear within the concentration range 0.01-1 μg/mL. The limit of detection and quantification of blood and urine samples were both estimated at 0.005 and 0.01 μg/mL. The interday and intraday precisions, accuracy, and recovery were assessed to verify this method. The results showed that the method was suitable for the determination of periplocymarin in forensic toxicological analysis and clinical diagnosis.

  20. Molecular-level characterization of crude oil compounds combining reversed-phase high-performance liquid chromatography with off-line high-resolution mass spectrometry

    Science.gov (United States)

    Sim, Arum; Cho, Yunju; Kim, Daae; Witt, Matthias; Birdwell, Justin E.; Kim, Byung Ju; Kim, Sunghwan

    2014-01-01

    A reversed-phase separation technique was developed in a previous study (Loegel et al., 2012) and successfully applied to the de-asphalted fraction of crude oil. However, to the best of our knowledge, the molecular-level characterization of oil fractions obtained by reversed-phase high-performance liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (MS) has not yet been reported. A detailed characterization of the oil fractions prepared by reversed-phase HPLC was performed in this study. HPLC fractionation was carried out on conventional crude oil and an oil shale pyrolysate. The analyses of the fractions showed that the carbon number of alkyl chains and the double bond equivalent (DBE) value were the major factors determining elution order. The compounds with larger DBE (presumably more condensed aromatic structures) and smaller carbon number (presumably compounds with short side chains) were eluted earlier but those compounds with lower DBE values (presumably less aromatic structures) and higher carbon number (presumably compounds with longer alkyl chains) eluted later in the chromatograms. This separation behavior is in good agreement with that expected from the principles of reversed-phase separation. The data presented in this study show that reversed-phase chromatography is effective in separating crude oil compounds and can be combined with ultrahigh-resolution MS data to better understand natural oils and oil shale pyrolysates.

  1. [Blood levels of homocysteine by high pressure liquid chromatography and comparison with two other techniques].

    Science.gov (United States)

    Ceppa, F; Drouillard, I; Chianea, D; Burnat, P; Perrier, F; Vaillant, C; El Jahiri, Y

    1999-01-01

    Cardio-vascular diseases are the most common cause of death in industrialized countries. A new marker has emerged among offending risk factors in the past few years: homocysteine. This sulphured amino-acid is an important intermediate in transsulphuration and remethylation reactions of methionine's metabolism. We proposed to evaluate a home made method of determination for this parameter by high performance liquid chromatography (HPLC) and to compare it to fluorescence polarization immunoassay technique (FPIA) and to gaz phase chromatography (CG-SM). This method associated with good sensibility and precision remain much less expensive than FPIA technique.

  2. Analysis of Non-Volatile Chemical Constituents of Menthae Haplocalycis Herba by Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Lu-Lu Xu

    2017-10-01

    Full Text Available Menthae Haplocalycis herba, one kind of Chinese edible herbs, has been widely utilized for the clinical use in China for thousands of years. Over the last decades, studies on chemical constituents of Menthae Haplocalycis herba have been widely performed. However, less attention has been paid to non-volatile components which are also responsible for its medical efficacy than the volatile constituents. Therefore, a rapid and sensitive method was developed for the comprehensive identification of the non-volatile constituents in Menthae Haplocalycis herba using ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap. Separation was performed with Acquity UPLC® BEH C18 column (2.1 mm × 100 mm, 1.7 μm with 0.2% formic acid aqueous solution and acetonitrile as the mobile phase under gradient conditions. Based on the accurate mass measurement (<5 ppm, MS/MS fragmentation patterns and different chromatographic behaviors, a total of 64 compounds were unambiguously or tentatively characterized, including 30 flavonoids, 20 phenolic acids, 12 terpenoids and two phenylpropanoids. Finally, target isolation of three compounds named Acacetin, Rosmarinic acid and Clemastanin A (first isolated from Menthae Haplocalycis herba were performed based on the obtained results, which further confirmed the deduction of fragmentation patterns and identified the compounds profile in Menthae Haplocalycis herba. Our research firstly systematically elucidated the non-volatile components of Menthae Haplocalycis herba, which laid the foundation for further pharmacological and metabolic studies. Meanwhile, our established method was useful and efficient to screen and identify targeted constituents from traditional Chinese medicine extracts.

  3. Optimisation of ultrasound-assisted reverse micelles dispersive liquid-liquid micro-extraction by Box-Behnken design for determination of acetoin in butter followed by high performance liquid chromatography.

    Science.gov (United States)

    Roosta, Mostafa; Ghaedi, Mehrorang; Daneshfar, Ali

    2014-10-15

    A novel approach, ultrasound-assisted reverse micelles dispersive liquid-liquid microextraction (USA-RM-DLLME) followed by high performance liquid chromatography (HPLC) was developed for selective determination of acetoin in butter. The melted butter sample was diluted and homogenised by n-hexane and Triton X-100, respectively. Subsequently, 400μL of distilled water was added and the microextraction was accelerated by 4min sonication. After 8.5min of centrifugation, sedimented phase (surfactant-rich phase) was withdrawn by microsyringe and injected into the HPLC system for analysis. The influence of effective variables was optimised using Box-Behnken design (BBD) combined with desirability function (DF). Under optimised experimental conditions, the calibration graph was linear over the range of 0.6-200mgL(-1). The detection limit of method was 0.2mgL(-1) and coefficient of determination was 0.9992. The relative standard deviations (RSDs) were less than 5% (n=5) while the recoveries were in the range of 93.9-107.8%. Copyright © 2014. Published by Elsevier Ltd.

  4. Determination of 15 isoflavone isomers in soy foods and supplements by high-performance liquid chromatography.

    Science.gov (United States)

    Yanaka, Kaoru; Takebayashi, Jun; Matsumoto, Teruki; Ishimi, Yoshiko

    2012-04-25

    Soy isoflavone is the generic name for the isoflavones found in soy. We determined the concentrations of 15 soy isoflavone species, including 3 succinyl glucosides, in 22 soy foods and isoflavone supplements by high-performance liquid chromatography (HPLC). The total isoflavone contents in 14 soy foods and 8 supplements ranged from 45 to 735 μg/g and from 1,304 to 90,224 μg/g, respectively. Higher amounts of succinyl glucosides were detected in natto, a typical fermented soy product in Japan; these ranged from 30 to 80 μg/g and comprised 4.1-10.9% of the total isoflavone content. In soy powder, 59 μg/g of succinyl glucosides were detected, equivalent to 4.6% of the total isoflavone content. These data suggest that the total isoflavone contents may be underestimated in the previous studies that have not included succinyl glucosides, especially for Bacillus subtilis -fermented soy food products.

  5. A novel strategy for the determination of polycyclic aromatic hydrocarbon monohydroxylated metabolites in urine using ultra-high-performance liquid chromatography with tandem mass spectrometry.

    Czech Academy of Sciences Publication Activity Database

    Lanková, D.; Urbancová, K.; Šrám, Radim; Hajslová, J.; Pulkrabová, J.

    2016-01-01

    Roč. 408, č. 10 (2016), s. 2515-2525 ISSN 1618-2642 R&D Projects: GA ČR(CZ) GA13-13458S Institutional support: RVO:68378041 Keywords : monohydroxylated metabolites of polycyclic aromatic hydrocarbons * SRM 3673 * tandem mass spectrometry * ultra-high-performance liquid chromatography * urine Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.431, year: 2016

  6. Elucidation and identification of amino acid containing membrane lipids using liquid chromatography/high-resolution mass spectrometry

    NARCIS (Netherlands)

    Moore, E.K.; Hopmans, E.C.; Rijpstra, W.I.C.; Villanueva, L.; Sinninghe Damsté, J.S.

    2016-01-01

    RATIONALE: Intact polar lipids (IPLs) are the building blocks of cell membranes, and amino acid containing IPLs havebeen observed to be involved in response to changing environmental conditions in various species of bacteri a. High-performance liquid chromatography/mass spectrometry (HPLC/MS) has

  7. Determination of limonin and nomilin contents in different citrus cultivars using high performance liquid chromatography

    International Nuclear Information System (INIS)

    Bilal, H.; Hassan, S.; Sahar, S.; Akram, W.; Sahar, S.

    2013-01-01

    High perlorrnance liquid chromatography (HPLC) analysis was done to quantify the amount of limonoids (nomilin and nomilin) in seven selected citrus cultivars. According to the HPLC analysis red blood orange (Citrus sinensis var red blood orange) had maximum amount of limonin (479.77 ug/rnl.), while rough lemon (Citrus jambhiri) had no limonin content. in case of nomonin, rough lemon (Citrus jambhir) had maximum amount of nomilin (54.23 micro g/ML)) while succari (citrus sinensis var succari) had very low amount of nomilin (0.37 micro g/Ml). (author)

  8. Determination of quantitative retention-activity relationships between pharmacokinetic parameters and biological effectiveness fingerprints of Salvia miltiorrhiza constituents using biopartitioning and microemulsion high-performance liquid chromatography.

    Science.gov (United States)

    Gao, Haoshi; Huang, Hongzhang; Zheng, Aini; Yu, Nuojun; Li, Ning

    2017-11-01

    In this study, we analyzed danshen (Salvia miltiorrhiza) constituents using biopartitioning and microemulsion high-performance liquid chromatography (MELC). The quantitative retention-activity relationships (QRARs) of the constituents were established to model their pharmacokinetic (PK) parameters and chromatographic retention data, and generate their biological effectiveness fingerprints. A high-performance liquid chromatography (HPLC) method was established to determine the abundance of the extracted danshen constituents, such as sodium danshensu, rosmarinic acid, salvianolic acid B, protocatechuic aldehyde, cryptotanshinone, and tanshinone IIA. And another HPLC protocol was established to determine the abundance of those constituents in rat plasma samples. An experimental model was built in Sprague Dawley (SD) rats, and calculated the corresponding PK parameterst with 3P97 software package. Thirty-five model drugs were selected to test the PK parameter prediction capacities of the various MELC systems and to optimize the chromatographic protocols. QRARs and generated PK fingerprints were established. The test included water/oil-soluble danshen constituents and the prediction capacity of the regression model was validated. The results showed that the model had good predictability. Copyright © 2017. Published by Elsevier B.V.

  9. Sensitive determination of D-lactic acid and L-lactic acid in urine by high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Henry, H; Marmy Conus, N; Steenhout, P; Béguin, A; Boulat, O

    2012-04-01

    D-lactic acid in urine originates mainly from bacterial production in the intestinal tract. Increased D-lactate excretion as observed in patients affected by short bowel syndrome or necrotizing enterocolitis reflects D-lactic overproduction. Therefore, there is a need for a reliable and sensitive method able to detect D-lactic acid even at subclinical elevation levels. A new and highly sensitive method for the simultaneous determination of L- and D-lactic acid by a two-step procedure has been developed. This method is based on the concentration of lactic acid enantiomers from urine by supported liquid extraction followed by high-performance liquid chromatography-tandem mass spectrometry. The separation was achieved by the use of an Astec Chirobiotic™ R chiral column under isocratic conditions. The calibration curves were linear over the ranges of 2-400 and 0.5-100 µmol/L respectively for L- and D-lactic acid. The limit of detection of D-lactic acid was 0.125 µmol/L and its limit of quantification was 0.5 µmol/L. The overall accuracy and precision were well within 10% of the nominal values. The developed method is suitable for production of reference values in children and could be applied for accurate routine analysis. Copyright © 2011 John Wiley & Sons, Ltd.

  10. Purification of flavonoids from licorice using an off-line preparative two-dimensional normal-phase liquid chromatography/reversed-phase liquid chromatography method.

    Science.gov (United States)

    Fan, Yunpeng; Fu, Yanhui; Fu, Qing; Cai, Jianfeng; Xin, Huaxia; Dai, Mei; Jin, Yu

    2016-07-01

    An orthogonal (71.9%) off-line preparative two-dimensional normal-phase liquid chromatography/reversed-phase liquid chromatography method coupled with effective sample pretreatment was developed for separation and purification of flavonoids from licorice. Most of the nonflavonoids were firstly removed using a self-made Click TE-Cys (60 μm) solid-phase extraction. In the first dimension, an industrial grade preparative chromatography was employed to purify the crude flavonoids. Click TE-Cys (10 μm) was selected as the stationary phase that provided an excellent separation with high reproducibility. Ethyl acetate/ethanol was selected as the mobile phase owing to their excellent solubility for flavonoids. Flavonoids co-eluted in the first dimension were selected for further purification using reversed-phase liquid chromatography. Multiple compounds could be isolated from one normal-phase fraction and some compounds with bad resolution in one-dimensional liquid chromatography could be prepared in this two-dimensional system owing to the orthogonal separation. Moreover, this two-dimensional liquid chromatography method was beneficial for the preparation of relatively trace flavonoid compounds, which were enriched in the first dimension and further purified in the second dimension. Totally, 24 flavonoid compounds with high purity were obtained. The results demonstrated that the off-line two-dimensional liquid chromatography method was effective for the preparative separation and purification of flavonoids from licorice. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Determination of Aspartame, Caffeine, Saccharin, and Benzoic Acid in Beverages by High Performance Liquid Chromatography.

    Science.gov (United States)

    Delaney, Michael F.; And Others

    1985-01-01

    Describes a simple and reliable new quantitative analysis experiment using liquid chromatography for the determinaiton of caffeine, saccharin, and sodium benzoate in beverages. Background information, procedures used, and typical results obtained are provided. (JN)

  12. High-performance liquid chromatographic characterization of dissolved organic matter from low-level radioactive waste leachates

    International Nuclear Information System (INIS)

    Caron, F.; Elchuk, S.; Walker, Z.H.

    1996-01-01

    Leachates from a waste degradation experiment, containing ∼700-3700 mg C/I of dissolved organic matter (DOM), were analyzed by high-performance liquid chromatography (HPLC) and liquid chromatography (LC), using various separation strategies. Scaling up of the separation scheme to a semi-preparative scale, suitable for hyphenated techniques, was also investigated. Separations with reversed-phase columns suggested that ∼70-93% of the DOM was hydrophilic, and ion-pair chromatography of this fraction showed the presence of several discrete compounds. Labile and non-labile complexes were formed by adding 60 Co radiotracer. Size-exclusion chromatography indicated that the DOM was primarily in the <1000-1500 Da molecular mass range. (author)

  13. High performance liquid chromatography-charged aerosol detection applying an inverse gradient for quantification of rhamnolipid biosurfactants.

    Science.gov (United States)

    Behrens, Beate; Baune, Matthias; Jungkeit, Janek; Tiso, Till; Blank, Lars M; Hayen, Heiko

    2016-07-15

    A method using high performance liquid chromatography coupled to charged-aerosol detection (HPLC-CAD) was developed for the quantification of rhamnolipid biosurfactants. Qualitative sample composition was determined by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The relative quantification of different derivatives of rhamnolipids including di-rhamnolipids, mono-rhamnolipids, and their precursors 3-(3-hydroxyalkanoyloxy)alkanoic acids (HAAs) differed for two compared LC-MS instruments and revealed instrument dependent responses. Our here reported HPLC-CAD method provides uniform response. An inverse gradient was applied for the absolute quantification of rhamnolipid congeners to account for the detector's dependency on the solvent composition. The CAD produces a uniform response not only for the analytes but also for structurally different (nonvolatile) compounds. It was demonstrated that n-dodecyl-β-d-maltoside or deoxycholic acid can be used as alternative standards. The method of HPLC-ultra violet (UV) detection after a derivatization of rhamnolipids and HAAs to their corresponding phenacyl esters confirmed the obtained results but required additional, laborious sample preparation steps. Sensitivity determined as limit of detection and limit of quantification for four mono-rhamnolipids was in the range of 0.3-1.0 and 1.2-2.0μg/mL, respectively, for HPLC-CAD and 0.4 and 1.5μg/mL, respectively, for HPLC-UV. Linearity for HPLC-CAD was at least 0.996 (R(2)) in the calibrated range of about 1-200μg/mL. Hence, the here presented HPLC-CAD method allows absolute quantification of rhamnolipids and derivatives. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Salt-induced phase separation for the determination of metals as their diethyldithiocarbamate complexes by high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Mueller, B.J.; Lovett, R.J.

    1987-01-01

    Reversed-phase high-performance liquid chromatography with ultraviolet detection can be used to determine trace levels of Pt(II), Pd(II), Rh(III), Co(III), Ru(III), and Ir in aqueous solution following complexation with diethyldithiocarbamate. The metal complexes are extracted into acetonitrile from aqueous solution by the addition of a saturated salt solution. Quantitative metal recovery from aqueous solution is achievable for most metals for a wide solution pH range. Detection limits for the metals are <3 ng of metal/mL of original aqueous sample. Analyses of real samples are highly reproducible and sensitive. Ir an interfere in the determination of Pt(II) and Rh(III). A general protocol for chromatographic separation and determination of Pt(II), Pd(II), Rh(III), Ru(III), and Ir in aqueous solution is presented

  15. Simultaneous determination and qualitative analysis of six types of components in Naoxintong capsule by miniaturized matrix solid-phase dispersion extraction coupled with ultra high-performance liquid chromatography with photodiode array detection and quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Wang, Huilin; Jiang, Yan; Ding, Mingya; Li, Jin; Hao, Jia; He, Jun; Wang, Hui; Gao, Xiu-Mei; Chang, Yan-Xu

    2018-02-03

    A simple and effective sample preparation process based on miniaturized matrix solid-phase dispersion was developed for simultaneous determination of phenolic acids (gallic acid, chlorogenic acid, ferulic acid, 3,5-dicaffeoylqunic acid, 1,5-dicaffeoylqunic acid, rosmarinic acid, lithospermic acid, and salvianolic acid B), flavonoids (kaempferol-3-O-rutinoside, calycosin, and formononetin), lactones (ligustilide and butyllidephthalide), monoterpenoids (paeoniflorin), phenanthraquinones (cryptotanshinone), and furans (5-hydroxymethylfurfural) in Naoxintong capsule by ultra high-performance liquid chromatography. The optimized condition was that 25 mg Naoxintong powder was blended homogeneously with 100 mg Florisil PR for 4 min. One milliliter of methanol/water (75:25, v/v) acidified by 0.05% formic acid was selected to elute all components. It was found that the recoveries of the six types of components ranged from 61.36 to 96.94%. The proposed miniaturized matrix solid-phase dispersion coupled with ultra high-performance liquid chromatography was successfully applied to simultaneous determination of the six types of components in Naoxintong capsules. The results demonstrated that the proposed miniaturized matrix solid-phase dispersion coupled with ultra high-performance liquid chromatography could be used as an environmentally friendly tool for the extraction and determination of multiple bioactive components in natural products. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Inulin in Medicinal Plants (IV) : Reversed-Phase High-Performance Liquid Chromatography of Inulin after Acetylation : Molecular-Weight Distribution of Inulin in Medicinal Plants

    OpenAIRE

    三野, 芳紀; 筒井, 聡美; 太田, 長世; YOSHIKI, MINO; SATOMI, TSUTSUI; NAGAYO, OTA; 大阪薬科大学; 大阪薬科大学; 大阪薬科大学; Osaka College of Pharmacy; Osaka College of Pharmacy; Osaka College of Pharmacy

    1985-01-01

    Reversed-phase high-performance liquid chromatography coupled with pre-acetylation enabled acculate molecular-weight assay of inulin in medicinal plants to be conducted. The results clearly showed that the molecular-weight distribution of inulin varied depending on the stage of growth: Small molecular weight inulin polymers were detected in large quantity in the earlier growth stage whereas large molecular weight inulin polymers at the flowering and post flowering period.

  17. Validation of a method for simultaneous determination of nitroimidazoles, benzimidazoles and chloramphenicols in swine tissues by ultra-high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Xia, Xi; Wang, Yuanyuan; Wang, Xia; Li, Yun; Zhong, Feng; Li, Xiaowei; Huang, Yaoling; Ding, Shuangyang; Shen, Jianzhong

    2013-05-31

    This paper presents a sensitive and confirmatory multi-residue method for the analysis of 23 veterinary drugs and metabolites belonging to three classes (nitroimidazoles, benzimidazoles, and chloramphenicols) in porcine muscle, liver, and kidney. After extracted with ethyl acetate and basic ethyl acetate sequentially, the crude extracts were defatted with hexane and further purified using Oasis MCX solid-phase extraction cartridges. Rapid determination was carried out by ultra-high performance liquid chromatography-electrospray ionization tandem mass spectrometry. Data acquisition was performed under positive and negative mode simultaneously. Recoveries based on matrix-matched calibrations for meat, liver, and kidney ranged from 50.6 to 108.1%. The method quantification limits were in the range of 3-100ng/kg. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Development of a high-performance liquid chromatography method for the determination of florfenicol in animal feedstuffs.

    Science.gov (United States)

    Yang, JinJing; Sun, GuiZhi; Qian, MingRong; Huang, LingLi; Ke, XianBing; Yang, Bo

    2017-11-15

    An effective thin layer chromatography (TLC) purification procedure coupled to high-performance liquid chromatography (HPLC) method was developed for the determination of florfenicol (FF) in pig, chicken and fish feedstuffs. The feedstuff samples were extracted with ethyl acetate, defatted with n-hexane saturated with acetonitrile, and further purified by TLC. The chromatographic separation was performed on a Waters Symmetry C 18 column using an isocratic procedure with acetonitrile-water (35:65, v/v) at 0.6mL/min. The ultraviolet (UV) detector was set at a wavelength of 225nm. The FF concentrations in feedstuff samples were quantified using a standard curve. Good linear correlations (y=159075x-15054, r>0.9999) were achieved within the concentration range of 0.05-200μg/mL. The recoveries of FF spiked at levels of 1, 100 and 1000μg/g ranged from 80.6% to 105.3% with the intra-day and inter-day relative standard deviation (RSD) less than 9.3%. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.02 and 0.06mg/kg for pig feedstuffs, 0.02 and 0.07mg/kg for chicken feedstuffs, and 0.02 and 0.05mg/kg for fish feedstuffs, respectively. This reliable, simple and cost-effective method could be applied to the routine monitoring of FF in animal feedstuffs. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Validation of a confirmatory method for the determination of melamine in egg by gas chromatography-mass spectrometry and ultra-performance liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    Xia Xi; Ding Shuangyang; Li Xiaowei; Gong Xiao; Zhang Suxia; Jiang Haiyang; Li Jiancheng; Shen Jianzhong

    2009-01-01

    A sensitive and reliable method was developed and validated for detection and confirmation of melamine in egg based on gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Trichloroacetic acid solution was used for sample extraction and precipitation of proteins. The aqueous extracts were subjected to solid-phase extraction by mixed-mode reversed-phase/strong cation-exchange cartridges. Using ultra-performance liquid chromatography and electrospray ionization in the positive ion mode, melamine was determined by LC-MS/MS, which was completed in 5 min for each injection. For the GC-MS analysis, extracted melamine was derivatized with N,O-bis(trimethylsilyl)trifluoracetamide prior to selected ion monitoring detection in electron impact mode. The average recovery of melamine from fortified samples ranged from 85.2% to 103.2%, with coefficients of variation lower than 12%. The limit of detection obtained by GC-MS and UPLC-MS/MS was 10 and 5 μg kg -1 , respectively. This validated method was successfully applied to the determination of melamine in real samples from market.

  20. High performance liquid chromatography--atomic fluorescence spectrometric determination of arsenic species in beer samples

    Energy Technology Data Exchange (ETDEWEB)

    Melo Coelho, N.M.; Parrilla, Carmen; Cervera, M.L.; Pastor, A.; Guardia, M. de la

    2003-04-10

    A method has been developed for the direct determination of As(III), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA) and As(V) in beers by hydride generation--atomic fluorescence spectrometry after separation of arsenic species by high performance liquid chromatography. Compounds were separated by anion-exchange chromatography with isocratic elution using KH{sub 2}PO{sub 4}/K{sub 2}HPO{sub 4} as mobile phase with elution times of 1.67, 2.08, 6.52 and 10.72 min for As(III), DMA, MMA and As(V), respectively. Parameters affecting the hydride generation of all arsenic species were studied and the best conditions were established as a reaction coil of 150 cm, for a sample injected volume of 100 {mu}l, a 4.0% (m/v) solution of sodium tetrahydroborate and 2.0 mol l{sup -1} hydrochloric acid with flow rates of 2.7 and 1.7 ml min{sup -1}, respectively and a flow rate of 500 ml min{sup -1} for the argon carrier gas. Under the best experimental conditions, the detection limit was found to be 0.12, 0.20, 0.27 and 0.39 {mu}g l{sup -1} for As(III), DMA, MMA and As(V), respectively. The relative standard deviation for eight independent determinations varied from 3.9 till 8.9% for species considered at a concentration level of 10.0 {mu}g l{sup -1}. Recovery and comparative studies evidenced that the method is suitable for the accurate determination of arsenic species in water and beer samples.