Journal articles: 'Liquid chromatography (HPLC)'

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Adel, E. Ibrahim, Elhenawee Magda, Saleh Hanaa, and M. Sebaiy Mahmoud. "Overview on liquid chromatography and its greener chemistry application." Annals of Advances in Chemistry 5, no. 1 (April 7, 2021): 004–12. http://dx.doi.org/10.29328/journal.aac.1001023.

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This literature review is concerning with liquid chromatography specifically high performance liquid chromatography (HPLC), Ultra high performance liquid chromatography (UHPLC), chromatography theory, chromatographic parameters, monolithic columns, principles of green chemistry and its application ingreen chromatography.

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Kataev, S. S., O. N. Dvorskaya, M. A. Gofenberg, A. V. Labutin, and A. B. Melentyev. "ANALYTICAL FEATURES OF SYNTHETIC MDMB(N)-073F CANNABIMIMETICS AND ITS MARKERS IN BIOLOGICAL MATERIAL." Pharmacy & Pharmacology 7, no. 4 (September 10, 2019): 184–97. http://dx.doi.org/10.19163/2307-9266-2019-7-4-184-197.

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The aim of the research is to study both analytical features of synthetic MDMB(N)-073F cannabimimetics of indazole carboxamides group by gas chromatography methods combined with tandem mass spectrometry (GC-MS) and high performance liquid chromatography with high-resolution mass spectrometry (HPLC-HRMS) as well as characteristics of the major MDMB(N)-073F metabolite, its glucuronide and derivatives, using gas chromatography with mass-spectrometric (GC-MS) detection and high-performance liquid chromatography (HPLC) with MS/MS mass spectrometry (HPLC-MS/MS) in urine samples to be applied in expert practice, chemical-toxicological and forensic and chemical analyses.Materials and methods. To carry out the study, the following materials were used: plant-based objects with narcotic drugs withdrawn from illegal trafficking and applied to them;. urine samples to be studied under chemical-toxicological and forensic and chemical analyses. For solid-phase epitaxy, SampliQ EVIDEX TFE cartridges – 200 mg – 3 ml (Agilent, USA) were used for sample preparation; β-glucuronidase, Type HP-2, From Helix Pomatia, 100000 UA/ml (Sigma-ALDRICH CHEMI, Germany) was used for enzymatic hydrolysis. GC-MS/MS analysis was made using Agilent 7890 gas chromatograph with a tandem quadrupolar mass-spectrometer Agilent 7000 (Agilent, США); GC-MS analysis was carrid out using gas chromatograph Agilent 7820 with mass-selective detector Agilent 5975 (Agilent, USA); HPLC-HRMS research was made on liquid chromatograph Agilent 1260 with tandem hybrid high-resolution quadrupole-time-of-flight detector Agilent 6540 (Agilent, США); liquid chromatograph Agilent 1260 with Agilent 6460 (Agilent, USA) with tandem mass-spectrometer were used for making HPLC-MS/MS research.Results. The structure of MDMB(N)-073F compound has been confirmed and an exact mass of the protonated molecule corresponding to the chemical formula C19H27FN3O3 fixed by GC-MS/MS and HPLC-HRMS methods. Spectral characteristics of MDMB(N)-073F have been given. One of the branches in MDMB(N)-073F biotransformation in the human body found out by GC-MS and HPLC-MS/MS methods, is the ester decomposition with further conjugation of the resulting acid. The product interacting with glucuronic acid, is found to be the conjugate of major MDMB(N)-073F metabolite of the Ist phase in biotransformation. Metabolites appearing due to the ester decomposition and its conjugate with glucuronic acid, are recommended to be used as markers for synthetic MDMB(N)-073F cannabimimetics in the analysis by chromatographic methods; they can be used for regular screening of biological samples.Conclusion. The research results presented here, are the following: the analytical features characteristic for synthetic MDMB(N)-073F cannabimimetics found out by gas chromatography methods combined with tandem mass spectrometry (GC-MS/ MS) and liquid chromatography of hybrid high-resolution quadrupole-time-of-flight mass spectrometry (HPLC-HRMS), as well as characteristics of major MDMB(N)-073F metabolite, its glucuronide and derivatives with the use of gas chromatography with mass-spectrometric detection (GC-MS) and liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS) in urine samples to be applied in expert practice, chemical-toxicological, forensic and chemical analyses.

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Hasany, Syeda Mariam, Rahila Huma, Sumia Akram, Rizwan Ashraf, and Muhammad Mushtaq. "Maceration-Mediated Liquid–Liquid Extraction and Reverse-Phase High-Performance Liquid Chromatography-Based Pragmatic Analysis of Silybins." Journal of Chromatographic Science 58, no. 8 (July 24, 2020): 779–87. http://dx.doi.org/10.1093/chromsci/bmaa035.

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Abstract This study presents a pragmatic and easily scalable maceration-mediated liquid–liquid extraction (MMLLE) and reverse-phase high-performance liquid chromatography (RP-HPLC)-based determination of Silybins from plant material (Curcuma longa L.). The processing of calibration standards revealed that the RP-HPLC method was linear over a concentration range of 1–100 μg/mL with regression coefficient (R2) > 0.9950, limit of detection 0.02 μg/mL and limit of quantification <0.07 μg/mL. The optimum chromatographic conditions resolved Silybin A, Silybin B, Isosilybin A and Isosilybin B within 5 min of analysis time. The reproducible recovery rates of spiked flavonolignans (96.24–115.40%) from quality controls established the effectiveness of MMLLE procedure prior to HPLC determination. The real-time analysis revealed the presence of silybins in C. longa roots. The results further endorse that MMLLE prior to chromatographic determination may provide a more pragmatic analytical solution for the analysis/isolation of silybins.

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Lochman, J., O. Šerý, L. Jankovský, and V. Mikes. "Discrimination of Czech Armillaria species based on PCR method and high performance liquid chromatography." Plant Protection Science 38, SI 1 - 6th Conf EFPP 2002 (January 1, 2002): S31—S34. http://dx.doi.org/10.17221/10316-pps.

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The genus Armillaria belongs to basidiomycetes and has been known to induce root rot disease and to cause extensive economic losses to a forest crop. We analysed about 40 isolates of Armillaria collected in Czech Republic by PCR and restriction analysis using gel electrophoresis and ion-exchange HPLC. Restrictase Hinf I was able to discriminate all investigated Armillaria species. The sensitivity and resolution of HPLC method was better than that performed by gel electrophoresis. HPLC was able to detect some heterozygous. The results prove the similarity of the species A. borealis, A. cepistipes, A. gallica, A. ostoyae in difference of A. mellea and A. tabescens.

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Kurbanoglu, Sevinc, Ozer Karsavurdan, and Sibel A. Ozkan. "Recent Advances on Drug Analyses Using Ultra Performance Liquid Chromatographic Techniques and their Application to the Biological Samples." Current Analytical Chemistry 15, no. 3 (May 7, 2019): 277–93. http://dx.doi.org/10.2174/1573411014666180423152612.

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Introduction: Ultra-Performance Liquid Chromatographic (UPLC) method enables analyst to establish an analysis at higher pressure than High Performance Liquid Chromatographic (HPLC) method towards liquid chromatographic methods. UPLC method provides the opportunity to study a higher pressure compared to HPLC, and therefore smaller column in terms of particle size and internal diameter are generally used in drug analysis. The UPLC method has attracted gradually due to its advantages such as short analysis time, the small amount of waste reagents and the significant savings in the cost of their destruction process. In this review, the recent selected studies related to the UPLC method and its method validation are summarized. The drug analyses and the results of the studies which were investigated by UPLC method, with certain parameters from literature are presented. Background: Quantitative determination of drug active substances by High-Performance Liquid Chromatography (HPLC) from Liquid Chromatography (LC) methods has been carried out since the 1970's with the use of standard analytical LC methods. In today's conditions, rapid and very fast even ultra-fast, flow rates are achieved compared to conventional HPLC due to shortening analysis times, increasing method efficiency and resolution, reducing sample volume (and hence injection volume), reducing waste mobile phase. Using smaller particles, the speed and peak capacity are expanding to new limit and this technology is named as Ultra Performance Liquid Chromatography. In recent years, as a general trend in liquid chromatography, ultra-performance liquid chromatography has taken the place of HPLC methods. The time of analysis was for several minutes, now with a total analysis time of around 1-2 minutes. The benefits of transferring HPLC to UPLC are much better understood when considering the thousands of analyzes performed for each active substance, in order to reduce the cost of analytical laboratories where relevant analysis of drug active substances are performed without lowering the cost of research and development activities. Methods: The German Chemist Friedrich Ferdinand Runge, proposed the use of reactive impregnated filter paper for the identification of dyestuffs in 1855 and at that time the first chromatographic method in which a liquid mobile phase was used, was reviewed. Christian Friedrich Chönbein, who reported that the substances were dragged at different speeds in the filter paper due to capillary effect, was followed by the Russian botanist Mikhail S. Tswet, who planted studies on color pigment in 1906. Tswet observes the color separations of many plant pigments, such as chlorophyll and xanthophyll when he passes the plant pigment extract isolated from plant through the powder CaCO3 that he filled in the glass column. This method based on color separation gives the name of "chromatographie" chromatography by using the words "chroma" meaning "Latin" and "graphein" meaning writing. Results and Conclusion: Because the UPLC method can be run smoothly at higher pressures than the HPLC method, it offers the possibility of analyzing using much smaller column sizes and column diameters. Moreover, UPLC method has advantages, such as short analysis time, the small amount of waste reagents and the significant savings in the cost of their destruction process. The use of the UPLC method especially analyses in biological samples such as human plasma, brain sample, rat plasma, etc. increasingly time-consuming due to the fact that the analysis time is very short compared to the HPLC, because of the small amount of waste analytes and the considerable savings in their cost.

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Durai Ananda Kumar T, Sai Charan, Venkateswarlu A, and Supriya Reddy K. "Evolution of liquid chromatography: Technologies and applications." International Journal of Research in Pharmaceutical Sciences 11, no. 3 (July 8, 2020): 3204–11. http://dx.doi.org/10.26452/ijrps.v11i3.2449.

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Liquid chromatographic offers efficient analyte separation employing high pressure pumps. The reversed phase high performance liquid chromatography (RP-HPLC) is widely utilized in the purity testing and quantitative determination of pharmaceuticals and neutraceuticals. The limitations of traditional liquid chromatography such as particle size, resolution and selectivity demanded for the developments and Waters Corporation developed ultraperformance liquid chromatography (UPLC). Ultrafast liquid chromatography (UFLC) is another milestone, which offers faster and efficient separation. Multidimensional UHPLC provides separation of complex molecules. The particle size decrease enhances the resolution of LC separation. Ethylene bridged hybrid (BEH), Charged surface hybrid (CSH) and Peptide separation technology (PST) offer better performance in. The amalgamation of chromatographic and spectroscopic detectors namely fluorescence detector (FD) and mass spectrometry (MS) provides efficient separation. Liquid chromatography (LC) offers the analysis of pharmaceuticals, biological, food materials, and natural products. This review covers technologies and recent pharmaceutical and biomedical applications of liquid chromatography technologies

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KRUGER, J. E., and B. A. MARCHYLO. "SELECTION OF COLUMN AND OPERATING CONDITIONS FOR REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY OF PROTEINS IN CANADIAN WHEAT." Canadian Journal of Plant Science 65, no. 2 (April 1, 1985): 285–98. http://dx.doi.org/10.4141/cjps85-041.

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Chromatographic conditions were optimized and three commercially available columns were evaluated for separation of alcohol-soluble storage proteins of Neepawa wheat using reversed-phase high-performance liquid chromatography (RP-HPLC). Optimal separation was achieved using an extracting solution of 50% 1-propanol, 1% acetic acid, and 4% dithiothreitol and an HPLC elution time of 105 min at a flow rate of 1.0 mL/min. HPLC columns evaluated (SynChropak RP-P, Ultrapore RPSC and Aquapore RP-300) varied in selectivity and resolution. The column providing the greatest versatility was Aquapore RP-300 available in cartridge form. Sodium dodecyl sulfate gradient-gel electrophoresis analysis of protein peaks resolved by RP-HPLC indicated that many of the eluted peaks contained more than one protein species. Chromatographic protein patterns obtained for Neepawa wheat grown at different locations and in different years were qualitatively the same.Key words: Protein, high-performance liquid chromatography, wheat

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Mekapothula, Subbareddy, A. D. Dinga Wonanke, Matthew A. Addicoat, David J. Boocock, John D. Wallis, and Gareth W. V. Cave. "Supramolecular Chromatographic Separation of C60 and C70 Fullerenes: Flash Column Chromatography vs. High Pressure Liquid Chromatography." International Journal of Molecular Sciences 22, no. 11 (May 27, 2021): 5726. http://dx.doi.org/10.3390/ijms22115726.

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A silica-bound C-butylpyrogallol[4]arene chromatographic stationary phase was prepared and characterised by thermogravimetric analysis, scanning electron microscopy, NMR and mass spectrometry. The chromatographic performance was investigated by using C60 and C70 fullerenes in reverse phase mode via flash column and high-pressure liquid chromatography (HPLC). The resulting new stationary phase was observed to demonstrate size-selective molecular recognition as postulated from our in-silico studies. The silica-bound C-butylpyrogallol[4]arene flash and HPLC stationary phases were able to separate a C60- and C70-fullerene mixture more effectively than an RP-C18 stationary phase. The presence of toluene in the mobile phase plays a significant role in achieving symmetrical peaks in flash column chromatography.

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Regnier, Fred E. "High-performance liquid chromatography (HPLC) of proteins." Fresenius' Zeitschrift für analytische Chemie 333, no. 7 (January 1989): 728. http://dx.doi.org/10.1007/bf00476585.

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Mladenovic, Aleksandar, Milka Jadranin, Aleksandar Pavlovic, Slobodan Petrovic, Sasa Drmanic, Milk Avramov-Ivic, and Dusan Mijin. "Liquid chromatography and liquid chromatography-mass spectrometry analysis of donepezil degradation products." Chemical Industry and Chemical Engineering Quarterly 21, no. 3 (2015): 447–55. http://dx.doi.org/10.2298/ciceq141023047m.

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This study describes the investigation of degradation products of donepezil (DP) using stability indicating RP-HPLC method for determination of donepezil, which is a centrally acting reversible acetylcholinesterase inhibitor. In order to investigate the stability of drug and formed degradation products, a forced degradation study of drug sample and finished product under different forced degradation conditions has been conducted. Donepezil hydrochloride and donepezil tablets were subjected to stress degradation conditions recommended by International Conference on Harmonization (ICH). Donepezil hydrochloride solutions were subjected to acid and alkali hydrolysis, chemical oxidation and thermal degradation. Significant degradation was observed under alkali hydrolysis and oxidative degradation conditions. Additional degradation products were observed under the conditions of oxidative degradation. The degradation products observed during forced degradation studies were monitored using the high performance liquid chromatography (HPLC) method developed. The parent method was modified in order to obtain LC-MS compatible method which was used to identify the degradation products from forced degradation samples using high resolution mass spectrometry. The mass spectrum provided the precise mass from which derived molecular formula of drug substance and degradation products formed and proved the specificity of the method unambiguously.

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Logoyda, Liliya, Dmytro Korobko, Serhii Kovalenko, and Iryna Ivanusa. "DEVELOPMENT OF THE METHODOLOGY OF THE CHROMATOGRAPHIC DETERMINATION OF NIFEDIPINE IN MEDICINES." Asian Journal of Pharmaceutical and Clinical Research 10, no. 3 (March 1, 2017): 149. http://dx.doi.org/10.22159/ajpcr.2017.v10i3.15841.

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ABSTRACTObjective: The aim was to develop a simple, rapid, less expensive, linear, precise, and accurate reverse phase high performance liquid chromatographymethod for determination of nifedipine in tablets.Methods: The chromatographic analysis of nifedipine was performed using liquid chromatograph Agilent 1290 Infinity II LC System. Selectedconditions were isocratic elution with binary mobile phase consisting of solution methanol and 0.1% trifluoroacetic acid (55:45). Detection wascarried out using spectrophotometric detector at 265 nm. The method was validated as per ICH guidelines.Results: The retention time for nifedipine by proposed high performance liquid chromatography (HPLC) method is observed as 3.5 minutes. Thecorrelation coefficients are 1.0000. The developed chromatographic method was found to be accurate with recovery 99.2-99.8% and was foundwithin the acceptance criteria (i.e. 98.0-102.0%) with acceptable % relative standard deviation of not more than 2% at each level. The assay results ofnifedipine in tablets by developed method are highly reproducible, reliable and are in good agreement with the label claim of the medicines (average99.62 %).Conclusion: Finally, it should be noted that a new simple, rapid, linear, precise, accurate HPLC method was developed and validated for thedetermination of nifedipine in medicines in accordance with the ICH guidelines. These results show the method are accurate, precise, sensitive,economic, and rugged. The proposed HPLC method is rapider (retention time is 3.5 minutes). This method can be useful for the routine analysis ofnifedipine in pharmaceutical dosage form.Keywords: Nifedipine, High-performance liquid chromatography, Validation, Linearity, Accuracy, Range of application.

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Basharat, Rabia, Vijay Kotra, Lean Yen Loong, Allan Mathews, Mahibub Mahamadsa Kanakal, CH B. Praveena Dev, Shaik Nyamathulla, et al. "A Mini-review on Ultra Performance Liquid Chromatography." Oriental Journal Of Chemistry 37, no. 4 (August 30, 2021): 847–57. http://dx.doi.org/10.13005/ojc/370411.

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Chromatography is a widely used analytical tool for separating a mixture of compounds into individual component. High performance liquid chromatography (HPLC) is one of the most important methods used for the separation, identification and quantification of a compounds present in a mixture. It meets many criteria of analysis but its main drawbacks are it is relatively time consuming to run a chromatogram and consumes high amount of solvent compared to other analytical methods. There is a need to develop a method which can overcome these drawbacks of HPLC. Ultra performance liquid chromatography (UPLC) is the new approach which opens novel direction in the field of liquid chromatography. It works on similar principle but shows better performance than conventional HPLC. UPLC is a technique of liquid chromatography with improved runtime and sensitivity with less than 2 μm particle size. The UPLC separation process is carried out under very high pressure (up to100 MPa). Additionally, it reduces the cost of reagent with shorter run time as compared to conventional HPLC. This article updated until 2020, provides a general review on the principle, instrumentation and application of UPLC in different fields of science.

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Wang, Bo, Jianyu Liu, Xia Zhao, Kaizhou Xie, Zhixiang Diao, Genxi Zhang, Tao Zhang, and Guojun Dai. "Determination of Eight Coccidiostats in Eggs by Liquid–Liquid Extraction–Solid-Phase Extraction and Liquid Chromatography–Tandem Mass Spectrometry." Molecules 25, no. 4 (February 22, 2020): 987. http://dx.doi.org/10.3390/molecules25040987.

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A method for the simultaneous determination of robenidine, halofuginone, lasalocid, monensin, nigericin, salinomycin, narasin, and maduramicin residues in eggs by liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed. The sample preparation method used a combination of liquid–liquid extraction (LLE) and solid-phase extraction (SPE) technology to extract and purify these target compounds from eggs. The target compounds were separated by gradient elution using high-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography (UPLC). Tandem mass spectrometry was used to quantitatively and qualitatively analyze the target compounds via electrospray ionization (ESI+) and multiple reaction monitoring mode. The HPLC–MS/MS and UPLC–MS/MS methods were validated according to the requirements defined by the European Union and the Food and Drug Administration. The limits of detection and limits of quantification of the eight coccidiostats in eggs were 0.23–0.52 µg/kg and 0.82–1.73 µg/kg for HPLC–MS/MS, and 0.16-0.42 µg/kg and 0.81-1.25 µg/kg for UPLC–MS/MS, respectively. The eggs were spiked with four concentrations of the eight coccidiostats, and the HPLC–MS/MS and UPLC–MS/MS average recoveries were all higher than 71.69% and 72.26%, respectively. Compared with the HPLC–MS/MS method, utilizing UPLC–MS/MS had the advantages of low reagent consumption, a short detection time, and high recovery and precision. Finally, the HPLC–MS/MS and UPLC–MS/MS methods were successfully applied to detect eight coccidiostats in 40 eggs.

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Sharma, Bhavik, and Sushil Kumar Agarwal. "RP-HPLC Method Development and Validation for Estimation of Acebrophylline." Asian Journal of Pharmaceutical Research and Development 6, no. 6 (February 14, 2019): 66–68. http://dx.doi.org/10.22270/ajprd.v6i6.445.

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Chromatography, a separation technique, is mostly used in chemical analysis in which High-performance liquid chromatography (HPLC) is an extremely versatile technique where analytes are separated by passage through a column packed with micrometer-sized particles. Theses day reversed-phase chromatography is commonly used separation technique in HPLC. The reasons for this include the simplicity, versatility, and scope of the reversed-phase method as it is able to handle compounds of a diverse polarity and molecular mass. Reversed phase chromatography has found both analytical and preparative applications in the area of biochemical separation and purification. Molecules that possess some degree of hydrophobic character, such as proteins, peptides and nucleic acids, can be separated by reversed phase chromatography with excellent recovery and resolution. This review covers the importance of RP-HPLC in analytical method development and their strategies along with brief knowledge of critical chromatographic parameters need to be optimized for an efficient method development. Key Words- HPLC, RP-HPLC

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Veizerová, L., J. Piešťanský, K. Maráková, J. Galba, D. Rauová, S. Dokupilová, E. Havránek, and P. Mikuš. "Comparison of column-coupled electrophoresis with liquid chromatography methods in food analysis of quinine." Acta Facultatis Pharmaceuticae Universitatis Comenianae 59, no. 1 (January 1, 2012): 67–80. http://dx.doi.org/10.2478/v10219-012-0011-y.

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Comparison of column-coupled electrophoresis with liquid chromatography methods in food analysis of quinineComparison of column-coupled electrophoresis with liquid chromatography methods in food analysis of quinine (QUI) is presented in this work. The capillary isotachophoresis (CITP) on-line coupled with capillary zone electrophoresis (CZE) and hyphenated with fibre-based spectrophotometric diode array detection (DAD) was compared with, (i) high performance liquid chromatography (HPLC) method with DAD detection, and (ii) HPLC method with fluorescence detection (FD). These methods were compared through their performance parameters and determined concentrations of QUI in beverages. The concentrations of QUI in two selected bitter drinks determined by the CITP-CZE-DAD method were in a good accordance with the HPLC-DAD and HPLC-FD methods. In addition, the electrophoretic method, as well as the chromatographic methods, was able to separate potential QUI related impurities from the QUI peak. The CITP-CZE-DAD method provided excellent performance parameters that were comparable (precision, accuracy, LOD, robustness) or even better (separation efficiency) than those ones provided by the chromatographic methods. Moreover, the effectivity of the electrophoresis method was higher when considering cost of analysis (equipment, consumption of separation systems), environmental aspects (organicvs. aqueous solvents), on-line sample pretreatment (CITP preconcentration and sample clean-up suitable also for the more complex matrices). Considering these findings, CITP-CZE-DAD was approved as a routine automatized method for the highly reliable quality food control.

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Hamza, Ouakouak, Ben Mohamed Moktar, Ben Chohra Mostafa, and Abdelhamid Zeghdaoui. "Phenobarbital Analysis in Biological Matrix (Blood) by High Performance Liquid Chromatography (HPLC)." International Letters of Chemistry, Physics and Astronomy 20 (October 2013): 31–40. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.20.31.

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In this work, we have tried to contribute to the analysis of phenobarbital in the blood. To do this, we used different analytical techniques such as liquid chromatography (HPLC). The results obtained in the course of our work, we can conclude that: The HPLC method was separate phenobarbital endogenous blood components, and optimizing the conditions of chromatographic separation as the composition of the mobile phase consisting of 20% acetonitrile + 20% methanol + 60% ammonium acetate buffer. The extraction with diethyl ether to pH = 4; The chromatographic column, microbondapack ZORBAX C18. A system of diode-array UV detection at 254 nm.

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Liu, Xing Rong, Jian Zheng, Dao Chen Zhu, and Yuan Mei Chen. "Determination of Puerarin and Daidzin from Pueraria Root Based on Chromatography." Advanced Materials Research 524-527 (May 2012): 2273–77. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2273.

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Combine thin layer chromatography ( TLC ) with high performance liquid chromatography ( HPLC ) detection of kudzu root isoflavones, to establish a rapid and accurate method to determine the component content of Puerarin and daidzin in Radix Puerariae.Though study on the optimization analysis of Puerarin Content in Radix Puerariae and daidzin content chromatography in a variety of conditions, including TLC developing solvent and options of coloration, and HPLC chromatographic separation conditions and detection characteristics of TLC and HPL, to get the best Chromatographic separation conditions and make a comparison with Puerarin pharmacopoeia test methods.The experimental results show that: TLC has the advantages of simple operation, rapid, reproducible, rapid identification of Puerarin and daidzin , HPLC with good stability, great accuracy and high precision that can be detected in puerarin and daidzin content. TLC and HPLC is a simple, fast, accurate method and contribute to the establishment of puerarin medicine standardized quality evaluation system and comprehensive utilization and development of Pueraria resources.

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Bhardwaj, Shalini, Vandana A., Vijay B., and Manish K. Gupta. "ULTRA PERFORMANCE LIQUID CHROMATOGRAPHY: A REVOLUTIONIZED LC TECHNIQUE." International Journal of Drug Regulatory Affairs 2, no. 3 (February 13, 2018): 83–87. http://dx.doi.org/10.22270/ijdra.v2i3.146.

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High Performance Liquid Chromatography (HPLC) is a major technique for qualitative and quantitative drug analysis. More than 90% of drugs prescribed in official pharmacopoeias are being analyzed HPLC. HPLC analyzes the drug content in a sample with high degree of accuracy and precision. Due to the stringent regulatory requirements the number of samples for drug content analysis has been increased significantly. Therefore, pharmaceutical industries need a fast, accurate and affordable method for drug content analysis. Here, Ultra Performance Liquid Chromatography (U-PLC) offers an advancement of HPLC which is based on the principal of use of stationary phase consisting of particles less than 2μm. By using smaller particles; speed and peak capacity can be extended to new limits and the sample can be analyzes in a shorter period of time. It provides good resolution even for congeneric compounds. The present review discusses the various aspects of UPLC in pharmaceutical analysis.

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Moore, R. A., and F. W. Karasek. "Fractionation of organic extracts of environmental water samples by low pressure column chromatography and high performance liquid chromatography techniques." Canadian Journal of Chemistry 63, no. 8 (August 1, 1985): 2110–18. http://dx.doi.org/10.1139/v85-347.

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Prefractionation procedures based on high performance liquid chromatography (hplc) and low pressure column chromatography (lpcc) were developed and applied to the separation of components in extracts of environmental samples. Effective fractionation was obtained using solvent systems based on hexane, carbon tetrachloride, dichloromethane, and ether for elution on lpcc Florisil and hplc silica columns. This facilitated the identification of over thirty compounds consisting mainly of aliphatic and polyaromatic hydrocarbons, phthalate esters, phenols, and pesticides in environmental samples extracted from water. Chromatographic background levels were minimized, and compounds whose chromatographic peaks were unresolved before fractionation were isolated into separate fractions. This afforded more highly reliable gc/ms identifications. Prefractionation also served to retard the rapid degradation of capillary columns which was caused by the injection of unfractionated samples.

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Domnina, Yu M., V. V. Suslov, S. A. Kedik, E. V. Vorfolomeeva, and A. V. Meleshko. "Quantitative Determination of Naltrexone Hydrochloride in a Nasal Spray by High-performance Liquid Chromatography." Drug development & registration 9, no. 2 (May 30, 2020): 98–104. http://dx.doi.org/10.33380/2305-2066-2020-9-2-98-104.

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Introduction. Naltrexone, an antagonist of µ-opioid receptors, is promising for the treatment of various autoimmune and oncological diseases when used in doses of 1.5–5 mg/day. To date, there are no medications that provide such dosages of naltrexone.Aim. Development and validation of a method for the quantitative determination of naltrexone hydrochloride in a nasal spray by high performance liquid chromatography (HPLC).Materials and methods. As an object of research, a naltrexone hydrochloride nasal spray was used. The quantitative determination of naltrexone in the test sample was developed using a Dionex UltiMate 3000 high-performance liquid chromatograph (Thermo Scientific, USA) equipped with a diode-matrix detector.Results and discussion. The possibility of using isocratic and gradient chromatographic modes for the quantitative determination of naltrexone hydrochloride in the nasal spray was studied. Based on these results, a new method of determination using the gradient mode is proposed, which allows minimizing the influence of the polymer component in the test sample on the analysis results.Conclusion. A new technique of high-performance liquid chromatography (HPLC) is proposed that allows identification and quantification of naltrexone hydrochloride in a nasal spray containing a high concentration of water-soluble heat-sensitive poloxamer as a thickener. The developed method was validated according to the parameters: correctness, precision, specificity, linearity.

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Tuzimski, Tomasz, and Anna Petruczynik. "Review of Chromatographic Methods Coupled with Modern Detection Techniques Applied in the Therapeutic Drugs Monitoring (TDM)." Molecules 25, no. 17 (September 3, 2020): 4026. http://dx.doi.org/10.3390/molecules25174026.

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Therapeutic drug monitoring (TDM) is a tool used to integrate pharmacokinetic and pharmacodynamics knowledge to optimize and personalize various drug therapies. The optimization of drug dosing may improve treatment outcomes, reduce toxicity, and reduce the risk of developing drug resistance. To adequately implement TDM, accurate and precise analytical procedures are required. In clinical practice, blood is the most commonly used matrix for TDM; however, less invasive samples, such as dried blood spots or non-invasive saliva samples, are increasingly being used. The choice of sample preparation method, type of column packing, mobile phase composition, and detection method is important to ensure accurate drug measurement and to avoid interference from matrix effects and drug metabolites. Most of the reported procedures used liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) techniques due to its high selectivity and sensitivity. High-performance chromatography with ultraviolet detection (HPLC-UV) methods are also used when a simpler and more cost-effective methodology is desired for clinical monitoring. The application of high-performance chromatography with fluorescence detection (HPLC-FLD) with and without derivatization processes and high-performance chromatography with electrochemical detection (HPLC-ED) techniques for the analysis of various drugs in biological samples for TDM have been described less often. Before chromatographic analysis, samples were pretreated by various procedures—most often by protein precipitation, liquid–liquid extraction, and solid-phase extraction, rarely by microextraction by packed sorbent, dispersive liquid–liquid microextraction. The aim of this article is to review the recent literature (2010–2020) regarding the use of liquid chromatography with various detection techniques for TDM.

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MORIOKA, Masaaki, Yozo OHASHI, Yasukazu SEN, Fumito KOMATSU, Yuko KONISHI, and Yukitoshi FUJITA. "Analysis of Corticoids in Adrenal Glands by High Performance Liquid Chromatography (HPLC)." Folia Endocrinologica Japonica 69, no. 1 (1993): 55–66. http://dx.doi.org/10.1507/endocrine1927.69.1_55.

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Akram, N. MD. "A Review on High Performance Liquid Chromatography (HPLC)." International Journal for Research in Applied Science and Engineering Technology 6, no. 2 (February 28, 2018): 488–92. http://dx.doi.org/10.22214/ijraset.2018.2098.

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Gamelin, L., P. Harry, E. Gamelin, M. Boisdron-Celle, and F. Costerousse. "Podophyllotoxin kinetics in plasma by liquid chromatography (HPLC)." Toxicology Letters 95 (July 1998): 73–74. http://dx.doi.org/10.1016/s0378-4274(98)80291-9.

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Ballschmiter, K., and M. Wößner. "Recent developments in adsorption liquid chromatography (NP-HPLC)." Fresenius' Journal of Analytical Chemistry 361, no. 8 (August 28, 1998): 743–55. http://dx.doi.org/10.1007/s002160051010.

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Ni, Fan, Jeffrey Ammann, and Abdul Mabud. "Monitoring Stevioside in Soju by High-Performance Liquid Chromatography and Liquid Chromatography/Mass Spectrometry." Journal of AOAC INTERNATIONAL 90, no. 5 (September 1, 2007): 1365–72. http://dx.doi.org/10.1093/jaoac/90.5.1365.

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Abstract A method using high-performance liquid chromatography (HPLC) with UV absorption detection was developed to monitor stevioside in soju, a distilled spirits product that is commercially available. The method uses a single-step dilution for sample preparation. It completely eliminates the time-consuming process of solid-phase extraction. A method using HPLC/mass spectrometry was optimized to confirm the identities of stevioside and other related impurities, including rebaudioside A, rebaudioside C, and dulcoside. The method was validated. The validation parameters included range (10.11007.3 ppm), precision, linearity, accuracy, robustness, system suitability, and intermediate precision. Stevioside standard solutions at 6 concentration levels were prepared for the validation work, including the tests for precision, linearity, and accuracy. The solutions were prepared in triplicate for each concentration. The relative standard deviation for the precision test was <3 for all 6 concentration levels. The correlation coefficient for the linearity within the concentration range was determined to be >0.999. The average recovery ranged from 95.7 to 101.1 for the soju samples spiked with stevioside standard. The detection limit for stevioside was estimated at 75 ppb. The method was used to screen several soju samples; no detectable stevioside was found in the samples.

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Liu, Si Quan, Yong Fang Chen, Li Guo Wang, and Rui Bao Jia. "Preparation and Characterization of Microcystins-LR by HPLC and HPLC-MS." Advanced Materials Research 236-238 (May 2011): 120–24. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.120.

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It is well known that microcystins (MCs) are the most abundant toxins produced by cyanobacteria in freshwater. The separation and characterization of MCs isomers are very important to the research of algal pollution in freshwater. In this paper MCs isomers were extracted by using methanol water solution and separated by reverse phase high performance liquid chromatography (HPLC). The different isomers were characterized by using HPLC-MS method. Different ratio of extract solvent and chromatographic conditions were discussed. Five MCs isomers were successfully extracted from cyanobacteria of Dianchi Lake. Three of which were characterized to be MC-RR, MC-YR and MC-LR, 1.5mg (92.3 purity) of MC-LR was prepared by using a semi-preparation HPLC system.

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Zhang, Xingping, Jiujun Wang, Qinghua Wu, Li Li, Yun Wang, and Hualin Yang. "Determination of Kanamycin by High Performance Liquid Chromatography." Molecules 24, no. 10 (May 17, 2019): 1902. http://dx.doi.org/10.3390/molecules24101902.

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Kanamycin is an aminoglycoside antibiotic widely used in treating animal diseases caused by Gram-negative and Gram-positive infections. Kanamycin has a relatively narrow therapeutic index, and can accumulate in the human body through the food chain. The abuse of kanamycin can have serious side-effects. Therefore, it was necessary to develop a sensitive and selective analysis method to detect kanamycin residue in food to ensure public health. There are many analytical methods to determine kanamycin concentration, among which high performance liquid chromatography (HPLC) is a common and practical tool. This paper presents a review of the application of HPLC analysis of kanamycin in different sample matrices. The different detectors coupled with HPLC, including Ultraviolet (UV)/Fluorescence, Evaporative Light Scattering Detector (ELSD)/Pulsed Electrochemical Detection (PED), and Mass Spectrometry, are discussed. Meanwhile, the strengths and weaknesses of each method are compared. The pre-treatment methods of food samples, including protein precipitation, liquid-liquid extraction (LLE), and solid-phase extraction (SPE) are also summarized in this paper.

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Munir, Muhammad Abdurrahman, Muhammad Mukram Mohamed Mackeen, Lee Yook Heng, and Khairiah Haji Badri. "Study of Histamine Detection using Liquid Chromatography and Gas Chromatography." ASM Science Journal 16 (July 26, 2021): 1–9. http://dx.doi.org/10.32802/asmscj.2021.809.

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Histamine is a heterocyclic amine shaped by decarboxylation of the histidine. It is a compound that lack chromophore and involatile. However, the detection of histamine is imperative due to the characteristic of histamine has given several disadvantages in food industry. This paper describes methods for histamine detection by employing high performance liquid chromatography and gas chromatography. The derivatization techniques required for both methods in order to increase the sensitivity of chromatography analysis. Two derivatizing agents were applied in this study such as 9-flourenilmethyl chloroformate (FMOC – Cl) for HPLC analysis whereas for GC analysis a N,O-bis (trimethylsilyl)acetamide (BSA) was used. Method validation was in accordance to Commission Decision 657/2002/CE. The validation of specificity, linearity, precision, accuracy, detection limit and quantitation limit results indicate that the methods were acceptable. The linear range for both methods were at 0.16 – 5.00 µg∙mL-1. The determination of histamine using GC showed the superiority of this instrument compared to HPLC. Method applicability was also checked on real sample namely mackerel in order to acquire a satisfactory recovery for both methods.

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Kholin, Andrey Yu, Svetlana V. Kurbatova, and Margarita N. Zemtsova. "Comparative analysis of the various structures quinoline derivatives retention under RP HPLC." Butlerov Communications 63, no. 8 (August 31, 2020): 31–39. http://dx.doi.org/10.37952/roi-jbc-01/20-63-8-31.

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The study results of the structure and physicochemical parameters effect of various quinoline derivatives on their retention under conditions of reversed-phase high-performance liquid chromatography are presented. It is shown that since the establishment of the relationship between the structure of a substance and its properties is still one of the most important problems of modern chemistry and materials science, chromatography is a very convenient and effective method for obtaining the information necessary for this. To establish the relationship between the structure and sorption characteristics of substances, on the one hand, the parameters of the electronic structure of sorbate molecules, their hydrophobic properties, quantum-chemical, topological and other physicochemical characteristics of organic compounds are used, as well as various computer programs and computer modeling methods that make it possible to analyze and to compare the numerous data on the chromatographic retention of compounds of various chemical nature, on the other. At the same time, for the final conclusions about the possibility of using the obtained dependences and correlations for assessing and predicting the properties of new compounds, a significant sample of compounds of various compositions is required, with the use of which the corresponding "structure – property" relationships are obtained. By now, reference books and computer databases on the chromatographic retention of organic compounds are known, containing information on a fairly large number of objects. However, these databases usually contain information predominantly about the retention of compounds under gas chromatography conditions. There are practically no corresponding libraries and databases for liquid chromatography, which is primarily due to the variety of liquid chromatographic systems differing both in the nature and composition of stationary phases and eluents, and in the chromatographic conditions. For the conditions of liquid chromatography, the possibility of using such schemes is complicated by the existence of a large number of interactions in the chromatographic system, due, first of all, to the presence of an active eluent. It is shown in this work that heterocyclic compounds are suitable models for these purposes, a feature of which is the possibility of modifying their properties by varying the structure within wide limits. In this work, the influence of the presence of heteroatoms, a change in the position of the same heteroatom in the main heterocyclic fragment, and the presence of functional groups and substituents of various natures on chromatographic retention under RP HPLC conditions were studied.

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An, Soonmo, Jiyoung Lee, and Wayne S. Gardner. "Stable Isotope Measurement of Ammonium Using HPLC-RTS (high performance liquid chromatography-retention time shift)." Sea 18, no. 1 (February 28, 2013): 47–52. http://dx.doi.org/10.7850/jkso.2013.18.1.47.

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Parys, Wioletta, Małgorzata Dołowy, and Alina Pyka-Pająk. "Current Strategies for Studying the Natural and Synthetic Bioactive Compounds in Food by Chromatographic Separation Techniques." Processes 9, no. 7 (June 24, 2021): 1100. http://dx.doi.org/10.3390/pr9071100.

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The present study summarizes the new strategies including advanced equipment and validation parameters of liquid and gas chromatography methods i.e., thin-layer chromatography (TLC), column liquid chromatography (CLC), and gas chromatography (GC) suitable for the identification and quantitative determination of different natural and synthetic bioactive compounds present in food and food products, which play an important role in human health, within the period of 2019–2021 (January). Full characteristic of some of these procedures with their validation parameters is discussed in this work. The present review confirms the vital role of HPLC methodology in combination with different detection modes i.e., HPLC-UV, HPLC-DAD, HPLC-MS, and HPLC-MS/MS for the determination of natural and synthetic bioactive molecules for different purposes i.e., to characterize the chemical composition of food as well as in the multi-residue analysis of pesticides, NSAIDs, antibiotics, steroids, and others in food and food products.

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Jančářová, I., A. Vondráčková, A. Šlampová, and V. Kubáň. "Capillary electrophoretic and liquid chromatographic determination of synthetic dyes in non-alcoholic drinks and wine samples." Czech Journal of Food Sciences 18, No. 2 (January 1, 2000): 41–48. http://dx.doi.org/10.17221/8307-cjfs.

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Synthetic dyes in wine, juices, lemonades, instant and non-alcoholic drinks were determined by capillary electrophoresis (CE) and liquid chromatography (HPLC) with UV-VIS diode-array detection (DAD). The results were in the very good agreement (the relative deviations D < 16%, D < 14% and D < 15% between CE/UV-VIS, CE/HPLC and HPLC/UV-VIS, respectively, D < 6% in majority of samples) with those obtained by UV-VIS spectrophotometry. A borate/phosphate buffer of pH 9.0 (12.5mM borate and 12.5mM phosphate) containing 40mM sodium dodecylsulfate (SDS) was selected as an electrolyte for CE. A 50mM phosphate buffer and 5mM tetrabutylammonium hydroxide (TBAOH) water solution of pH 4.2 in 38% (v/v) acetonitrile were used as a mobile phase for isocratic HPLC separation on Sepharon SGX C18 (3 × 150 mm, 5 µm) column. RSDs for individual colorants were < 0.5% for migration times, < 3% for electrophoretic peak areas, < 0.9% for retention times and < 2.4% for HPLC peak areas. Limits of quantitations (LOQs for 10 S/N) were 1.5–3.3 mg/l for CE when using 50 µm I.D. separation capillary or 0.2 to 0.4 mg/l for HPLC.

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Pourbasheer, Eslam, Samira Sadafi, Mohammad Reza Ganjali, and Maryam Abbasghorbani. "Dispersive liquid–liquid microextraction for preconcentration and determination of phenytoin in real samples using response surface methodology-high performance liquid chromatography." RSC Adv. 4, no. 107 (2014): 62190–96. http://dx.doi.org/10.1039/c4ra10223a.

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In the present study, dispersive liquid–liquid microextraction (DLLME) was developed for preconcentration and determination of phenytoin in real samples by high performance liquid chromatography (HPLC).

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Eltekova, N. A., and Yu A. Eltekov. "High-Performance Liquid Chromatography as Physico-Chemical Method for Study of Adsorption from Solutions." Adsorption Science & Technology 5, no. 1 (March 1988): 1–12. http://dx.doi.org/10.1177/026361748800500102.

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High-Performance liquid chromatography (HPLC) of anisole and benzaldehyde on macroporous silica (Silochrom C80) with a hydroxylated surface and a surface covered with polyoxyethylene (POE) monolayer have been studied. On the basis of data obtained from liquid adsorption chromatography the adsorption isotherms of aromatic compounds from solutions were calculated. It has been found that adsorption isotherms obtained by HPLC and static adsorption methods coincide for anisole adsorbed either on hydroxylated or modified surfaces. In the case of benzaldehyde adsorption on hydroxylated silica surface the adsorption values obtained by the chromatographic method are smaller than those obtained by static adsorption method due to specific features of adsorption kinetics. Henry's constants, KΓ distribution factors, f, and adsorption solution activity coefficient, γa,i, for anisole and benzaldehyde adsorbed on hydroxylated and POE modified silica have been calculated. The values of KΓ and f obtained by both the static adsorption and HPLC methods have been compared. The enthalpies and entropies of adsorption of aromatic compounds have been compared with the polarity parameters.

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Takatsu, A., and S. Nishi. "Total cholesterol in serum determined by isotope dilution/mass spectrometry, with liquid-chromatographic separation." Clinical Chemistry 33, no. 7 (July 1, 1987): 1113–17. http://dx.doi.org/10.1093/clinchem/33.7.1113.

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Abstract We describe an accurate, precise method for determination of total serum cholesterol by isotope dilution/mass spectrometry (IDMS) with liquid-chromatographic separation. After adding [3,4-13C]cholesterol to serum and hydrolyzing the cholesterol esters, we extract the total cholesterol. "High-performance" liquid chromatography (HPLC) is used to separate the extracted cholesterol for measurement by electron-impact mass spectrometry with use of a direct-insertion device. To evaluate the specificity and the accuracy of this method, we also studied the conventional IDMS method, which involves converting cholesterol to the trimethylsilyl ether and assay by gas chromatography-mass spectrometry with use of a capillary column. The coefficient of variation for the HPLC method was a little larger than that for the conventional method, but mean values by each method agreed within 1% for all sera tested.

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Kosicka, Katarzyna, Anna Siemiątkowska, Agata Szpera-Goździewicz, Mariola Krzyścin, Grzegorz Bręborowicz, and Franciszek Główka. "High-performance liquid chromatography methods for the analysis of endogenous cortisol and cortisone in human urine: comparison of mass spectrometry and fluorescence detection." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 56, no. 1 (June 25, 2018): 82–89. http://dx.doi.org/10.1177/0004563218783789.

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Background The analysis of steroids in biological matrices is challenging. One can apply immunoassay as well as gas and liquid chromatography with various types of detection, depending on the available equipment and the experience of the analyst. The question is how the methods are interchangeable between themselves. Doubts were reported having compared immunoassays and chromatography-mass spectrometry, but there are scarce data on chromatographic methods with detection types other than mass spectrometry. Methods Here, we present the detailed comparison of two liquid chromatographic methods for the determination of free urinary cortisol and cortisone: one with fluorescence detection (high-performance liquid chromatography [HPLC-FLD]) and the other with tandem mass spectrometry (HPLC-MS/MS). The comparison was made with 199 human urine samples. The data analysis included Passing–Bablok and Deming regression, Bland–Altman test, Wilcoxon test, mountain plot and Lin’s concordance correlation coefficient. Results The validation data indicated that both methods met the requirements of the European Medicines Agency. However, the statistical analysis revealed the systematic bias between the two assays. The Passing–Bablok and the Deming tests showed that the HPLC-FLD method overestimated results for cortisol and underestimated measurements for cortisone. The Bland–Altman analysis estimated the mean differences between the methods: 18.8 nmol/L for cortisol and −16.9 nmol/L for cortisone measurement. Conclusions Both methods’ results led to the same conclusion in observational studies, but the techniques are not interchangeable. The literature data, the observations from the clinical setting and our experience clearly indicate that the future of steroid measurements will belong to chromatography coupled with mass spectrometry.

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Rosales-Castro, Martha, Rubén Francisco González-Laredo, Nuria Elizabeth Rocha-Guzmán, José Alberto Gallegos-Infante, María José Rivas-Arreola, and Joseph J. Karchesy. "Antioxidant activity of fractions from Quercus sideroxyla bark and identification of proanthocyanidins by HPLC-DAD and HPLC-MS." Holzforschung 66, no. 5 (July 1, 2012): 577–84. http://dx.doi.org/10.1515/hf-2011-0157.

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Abstract The most active phenolics in Quercus sideroxyla Humb. & Bonpl. residual bark were identified and evaluated following a chromatographic fractionation. Bark powder was defatted with hexane and crude extract (CE) was obtained by extraction with aqueous acetone (70%). A liquid partition with ethyl acetate was performed to produce an organic extract (OE), which was subsequently purified by column chromatography (Toyopearl HW-40F, methanol), and resulted in six methanolic fractions (MF1 to MF6) and an oligomeric fraction (OLF) eluted with acetone 67%. Extraction yields, total phenolic and flavanol contents were determined. The antioxidant activity of bark extracts was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox (6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic-acid)-equivalent antioxidant capacity (TEAC), and ferric ion reducing antioxidant power (FRAP) assays. Their median effective concentration (EC50) data and rate constants for DPPH radical scavenging were also estimated. Identification of major phenolics was carried out by high performance liquid chromatography with diode array detection (HPLC-DAD) and high performance liquid chromatography with electrospray ionization coupled to mass spectrometry (HPLC-ESI-MS) instruments. Bioactive gallic acid, catechin, epicatechin, gallocatechin, catechin gallate, dimeric procyanidins, galloylated dimeric proanthocyanidins, trimeric procyanidins, and tetrameric proanthocyanidins were detected and identified in Q. sideroxyla bark extracts. MF2 was the most active fraction containing gallocatechin as its major compound; MF5 and OLF contain galloylated procyanidins, which may explain their higher antiradical activity. OLF besides galloylated procyanidins has gallocatechin, which presumably contributes to its higher antiradical activity. Consequently, Q. sideroxyla bark could be a good source of therapeutic health products or nutraceutical ingredients that may exert a potential prevention or treatment action against diseases in biological systems.

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Seo, Chang-Seob, and Hyeun-Kyoo Shin. "Development of a Reverse-Phase High-Performance Liquid Chromatography and Liquid Chromatography Tandem Mass Spectrometry Methods for Quality Control of Daegunjoong-Tang." Applied Sciences 11, no. 8 (April 12, 2021): 3437. http://dx.doi.org/10.3390/app11083437.

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Daegunjoong-tang (DGJT) is an oriental medicine consisting of four medicinal herbs (Zingiber officinale Rosc., Panax ginseng C.A.Mey., Oryza sativa L., and Zanthoxylum schinifolium Sieb. et Zucc.) that is used to treat intestinal- and cancer-related diseases. In this study, a protocol for quality control of DGJT based on reverse-phase high-performance liquid chromatography (HPLC) and liquid chromatography tandem mass spectrometry (LC–MS/MS) analysis were developed. In HPLC analysis, the marker analytes (hyperoside, quercitrin, ginsenoside Rg1, and 6-gingerol) were separated, verified, and quantified using a mobile phase of 0.1% (v/v) aqueous formic acid–0.1% (v/v) formic acid in acetonitrile system, and a C18 reverse-phase column (4.6 mm × 250 mm, particle size; 5 m) maintained at 40 °C. In LC–MS/MS analysis, all analytes were separated using a Waters Acquity UPLC BEH C18 column (2.1 mm × 100 mm, particle size; 1.7 μm). Using the developed HPLC and LC–MS/MS methods, the four marker analytes were found in the samples at 0.95–13.86 mg/g (HPLC) and 0.27–2.42 mg/g (LC–MS/MS). The assay will be useful for evaluating the quality of DGJT.

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Niwa, T. "Phenol and p-cresol accumulated in uremic serum measured by HPLC with fluorescence detection." Clinical Chemistry 39, no. 1 (January 1, 1993): 108–11. http://dx.doi.org/10.1093/clinchem/39.1.108.

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Abstract We developed a simple and sensitive high-performance liquid chromatographic (HPLC) method that uses fluorescence as a detector for quantifying serum phenol and p-cresol in uremic patients on hemodialysis. Identification of phenol and p-cresol was confirmed by liquid chromatography/mass spectrometry. Because the HPLC method requires only simple extraction by ethyl acetate and does not require further steps such as derivatization, it is simple and rapid compared with gas chromatography or gas chromatography/mass spectrometry. Concentrations of phenol and p-cresol in uremic serum were significantly (p < 0.01) higher than those in normal serum. Reduction rates of phenol and p-cresol by hemodialysis were lower than those of urea and creatinine, suggesting a protein-binding property of phenol and p-cresol. This method will be useful for monitoring serum phenols in dialyzed patients as an index of hemodialysis adequacy.

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Doctor, Ninad, and Yu Yang. "Separation and Analysis of Aspirin and Metformin HCl Using Green Subcritical Water Chromatography." Molecules 23, no. 9 (September 5, 2018): 2258. http://dx.doi.org/10.3390/molecules23092258.

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Organic solvents are widely used in pharmaceutical and chemical industry for chromatographic separations. In recent years, subcritical water chromatography (SBWC) has shown ability in replacing hazardous organic solvents used in traditional high-performance liquid chromatography (HPLC). In this work, a pain killer—aspirin—and an antidiabetic drug—metformin HCl—were successfully separated on an XBridge C18 column using no organic solvents in the subcritical water chromatography mobile phase. Both traditional HPLC and subcritical water chromatography were used for comparison purposes. SBWC separation of metformin HCl and aspirin were achieved at 95 °C and 125 °C, respectively. The recovery for both active pharmaceutical ingredients (APIs) obtained by SBWC is 99% in comparing with the stated content of each drug. The relative standard deviation is less than 1% for SBWC assays developed in this work. This level of accuracy and precision achieved by SBWC is the same as that resulted by the traditional HPLC analysis.

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Shen, Yao, Bo Chen, and Teris A. van Beek. "Alternative solvents can make preparative liquid chromatography greener." Green Chemistry 17, no. 7 (2015): 4073–81. http://dx.doi.org/10.1039/c5gc00887e.

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Wróblewski, Karol, Anna Petruczynik, Tomasz Tuzimski, Dominika Przygodzka, Grzegorz Buszewicz, Patrycjusz Kołodziejczyk, and Piotr Tutka. "Comparison of Various Chromatographic Systems for Analysis of Cytisine in Human Serum, Saliva and Pharmaceutical Formulation by HPLC with Diode Array, Fluorescence or Mass Spectrometry Detection." Molecules 24, no. 14 (July 16, 2019): 2580. http://dx.doi.org/10.3390/molecules24142580.

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Background: Identification and quantitative determination of cytisine, especially in biological samples and pharmaceutical formulations, is still a difficult analytical task. Cytisine is an alkaloid with a small and very polar molecule. For this reason, it is very weakly retained on reversed phase (RP) stationary phases, such as commonly used alkyl-bonded phases. The very weak retention of cytisine causes it to be eluted together with the components of biological matrices. Objective: Comparison and evaluation of various chromatographic systems for analysis of cytisine in different matrices—serum, saliva and pharmaceutical formulation—by high performance liquid chromatography (HPLC) with diode array (DAD), fluorescence (FLD) and mass spectrometry (MS) detection. Methods: The analyses were performed using HPLC in reversed phase (RP), hydrophilic interaction liquid chromatography (HILIC) and ion exchange chromatography (IEC) modes. Different sample pre-treatment methods were tested: Protein precipitation (with acetone, methanol (MeOH) or acetonitrile (ACN), and solid phase extraction (SPE) using cartridges with octadecyl (C18), hydrophilic-lipophilic balanced copolymer (HLB) or strong cation exchange sorbents (Strata X-C). Conclusion: Significant differences were observed in retention parameters with a change of the used chromatographic system. The various properties of stationary phases resulted in differences in analyte retention, peaks’ shape and systems’ efficiency. The weakest retention was observed using RP systems; however, the use of the Polar RP phase can be an alternative for application in green chromatography. In the strongest retention was observed using a strong cation exchange (SCX) phase. The most optimal systems were chosen for the analysis of cytisine in the pharmaceutical preparation, serum and saliva after sample pre-treatment with the new SPE procedure. Due to the sensitivity, the use of HPLC-DAD or HPLC-FLD is the most optimal for drug analysis in pharmaceutical preparations, whereas HPLC-MS is suitable for analysis of cytisine in biological samples.

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Yang, Yiwen, Yehui Wang, Zongbi Bao, Qiwei Yang, Zhiguo Zhang, and Qilong Ren. "Progress in the Enantioseparation of β-Blockers by Chromatographic Methods." Molecules 26, no. 2 (January 17, 2021): 468. http://dx.doi.org/10.3390/molecules26020468.

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β-adrenergic antagonists (β-blockers) with at least one chiral center are an exceedingly important class of drugs used mostly to treat cardiovascular diseases. At least 70 β-blockers have been investigated in history. However, only a few β-blockers, e.g., timolol, are clinically marketed as an optically pure enantiomer. Therefore, the separation of racemates of β-blockers is essential both in the laboratory and industry. Many approaches have been explored to obtain the single enantiomeric β-blocker, including high performance liquid chromatography, supercritical fluid chromatography and simulated moving bed chromatography. In this article, a review is presented on different chromatographic methods applied for the enantioseparation of β-blockers, covering high performance liquid chromatography (HPLC), supercritical fluid chromatography (SFC) and simulated moving bed chromatography (SMB).

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Lin, Chao-Zhan, Run-Jing Zhang, Yu-Feng Yao, Xiao-Dan Huang, Rong-Bo Zheng, Bo-Jian Wu, and Chen-Chen Zhu. "Qualitative and Quantitative Analysis of the Major Constituents in WLJ Herbal Tea Using Multiple Chromatographic Techniques." Molecules 23, no. 10 (October 12, 2018): 2623. http://dx.doi.org/10.3390/molecules23102623.

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Quality control of Chinese herbal tea remains a challenge due to our poor knowledge of their complex chemical profile. This study aims to investigate the chemical composition of one of the best-selling and famous brand of beverage in China, Wanglaoji Herbal Tea (WLJHT), via a full component quantitative analysis. In this paper, a total of thirty-two representative constituents were identified or tentatively characterized using ultra-high performance liquid chromatography coupled with quadrupole tandem time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Moreover, the quantitative analyses of fourteen constituents were performed by high performance liquid chromatography with a triple quadruple tandem mass spectrometry (HPLC-MS/MS) method and saccharide compositions of WLJHT were also quantitatively determined by high performance liquid chromatography (HPLC) with evaporative light scattering detector (ELSD) on a Hilic column, separately. Using multiple chromatographic techniques presented a good precision, sensitivity, repeatability and stability, and was successfully applied to analyze 16 batches of WLJHT samples. Therefore, it would be a reliable and useful approach for the quality control of WLJHT.

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Siva Madhu Chaitanya, Srinath Nissankararao, and Satya Lakshmi Gandham. "A sort of validated Bioanalytical method developed for the estimation of Etoposide and Cisplatin in rat plasma by using two different advanced liquid chromatographic techniques like HPLC and UPLC and its application in bioequivalence studies." International Journal of Research in Pharmaceutical Sciences 12, no. 1 (January 13, 2021): 708–17. http://dx.doi.org/10.26452/ijrps.v12i1.4167.

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An easy, quick, precise, active and reproducible reverse method high performance liquid chromatography (RP-HPLC), as well as Ultra pressure liquid chromatography (UPLC) unique technique, was developed for the bioanalytical method of Etoposide and Cisplatin with Oxaplatin as an internal standard. Chromatographic analysis was performed using HPLC was Waters Alliance e-2695, and UPLC was Waters Acquity UPLC by using x-bridge phenyl 150x4.6mm, 3.5µ column and therefore the mobile phase containing 0.1% triethylamine and acetonitrile at a ratio out of 60:40 v/v. The flow rate was 1 ml/min, and analytes were detected at 283 nm employing a photodiode array detector at ambient temperature in both liquid chromatographic systems. The proposed biological method was proved in both HPLC and UPLC with USFDA guidelines. USP tailing is 1.1, 1.02 for etoposide and 1.16, 1.05 for Cisplatin in HPLC and UPLC. USP plate count is 4794, 3884 for Etoposide and 9289, 14487 for Cisplatin. The calibration curve under accumulation set of 5-100 ng/ml of etoposide and 10-200 ng/ml of Cisplatin in both HPLC and UPLC. The accuracy of low, middle and high-level quality control samples are taken in 50%, 100% and 150% levels. Stability study was administered altogether conditions are bench top, wet extract and auto sampler, freeze-thaw, short term stability and in long term stability. This is the advanced technique established to the straightforward, economical, suitable, precise, accurate and stable method for the analysis of Etoposide and Cisplatin and study of its stability and pharmacokinetic studies using rat plasma.

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47

Freeman, R. D., R. M. Hammaker, C. E. Meloan, and W. G. Fateley. "A Detector for Liquid Chromatography and Flow Injection Analysis Using Surface-Enhanced Raman Spectroscopy." Applied Spectroscopy 42, no. 3 (March 1988): 456–60. http://dx.doi.org/10.1366/0003702884427997.

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A successful interface between a high-performance liquid chromatograph and a Raman spectrometer is described. Surface-enhanced techniques are utilized to overcome the sensitivity problem inherent to conventional Raman spectrometry by adding a Ag sol to the chromatographic effluent in a post-column mixing coil. The system is designed so that Raman spectra may be obtained from chromatographic effluent or from flow injection analysis effluent. A common organic dye (pararosaniline hydrochloride) is used to evaluate the reproducibility, dynamic range, and analytical capabilities of the system. The SERS instrument is found to be a viable detector for HPLC and FIA, capable of providing structural information with a sensitivity comparable to that of other commonly used HPLC detectors.

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48

Botek, P., J. Poustka, and J. Hajšlová. "Determination of banned dyes in spices by liquid chromatography−mass spectrometry." Czech Journal of Food Sciences 25, No. 1 (January 7, 2008): 17–24. http://dx.doi.org/10.17221/737-cjfs.

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A simple and rapid multiresidue method for the determination of nine banned synthetic dyes in various spices has been developed. Reversed phase HPLC coupled with mass spectrometry (tandem in time−ion trap mass analyser) was employed for the examination of crude acetonitrile extract acidified with acetic acid. The detection limits of Para Red, Sudan Orange G, Sudan I, Sudan II, Sudan III, Sudan IV, Sudan Red 7B and Rhodamine B were in the range of 0.02−0.1 mg/kg, the recoveries ranged from 75.7−92.3% with repeatability of 0.9−11.3%. Rather worse performance characteristics were obtained with Tropaeolin 000, obviously due to its more polar nature as compared to other dyes involved in this study. In spite of that, the developed method can be used for a reliable control of a wide range of dyes used for illegal colouring of various spices.

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49

Keevil, B. G., P. W. Maylor, and D. Rowlands. "A Rapid Anion Exchange High-Performance Liquid Chromatography Method for the Measurement of HbA2 in Whole Blood." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 33, no. 3 (May 1996): 253–56. http://dx.doi.org/10.1177/000456329603300313.

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We developed a binary gradient high-performance liquid chromatography (HPLC) method for measuring HbA2 in whole blood samples using a Pharmacia Mono Q column (1 mL) and measurement at 415 nm. The assay requires a simple lysis and centrifugation step before injection onto the column. We found good agreement of results between the HPLC method and the Helena column chromatography method. The within batch precision was 2·6% and between batch precision was 4·6%. We found that using 30 mM Tris buffers (pH 7·8) with a sodium chloride gradient resulted in short analysis times and good chromatographic separation of HbA2, HbS and HbA. We conclude that this is a robust assay for the diagnosis of β-thalassaemia.

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50

Rittenhouse, Robert C. "HPLC: A computer simulation of high-performance liquid chromatography." Journal of Chemical Education 65, no. 12 (December 1988): 1050. http://dx.doi.org/10.1021/ed065p1050.

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Journal articles on the topic 'Liquid chromatography (HPLC)'

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