Journal articles: 'HPLC (high-performance liquid chromatography)'

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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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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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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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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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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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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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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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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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K., Hari Ramakrishnan, and Janaky Ranjithkumar. "Quantitative Determination of Vitamin E Isomers using Gas Chromatography, High Performance Liquid Chromatography and High Performance Thin Layer Chromatography." Indian Journal of Nutrition and Dietetics 54, no. 3 (July 4, 2017): 294. http://dx.doi.org/10.21048/ijnd.2017.54.3.15589.

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Vitamin E, the fat soluble vitamin is present naturally in some foods and added in food supplements, nutraceuticals etc due to its vital biological function as an antioxidant. Various methods are available for the analysis of vitamin E. Especially High Performance Liquid Chromatography (HPLC) and Gas Chromatography (GC) are exclusively used for the quantitative evaluation of vitamin E, which has also identified the four different isomeric forms of this vitamin. The rate of losses of this vitamin during food processing and analysis, in addition to their transient dynamics, presents complexities in developing a highly sensitive procedure for their separations. Though effective, HPLC instrument is expensive and comparatively cumbersome. In this prospective, the study was to evaluate the usefulness of High Performance Thin Layer Chromatography (HPTLC) in the analysis of vitamin E. There are methods available using Thin Layer Chromatography for its analysis, but they are not sensitive enough to identify the isomeric forms of vitamin E. In this HPTLC method, the different isomeric forms of vitamin E - α, β, γ and δ were identified. This technique shall be considered as an alternative to the other methods such as HPLC and GC.

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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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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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Nikolin, Branko, Belma Imamović, Saira Medanhodžić-Vuk, and Miroslav Sober. "High performance liquid chromatography in pharmaceutical analyses." Bosnian Journal of Basic Medical Sciences 4, no. 2 (May 20, 2004): 5–9. http://dx.doi.org/10.17305/bjbms.2004.3405.

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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 serum contains numerous endogenous compounds often present in concentrations much greater than those of analyte. Analiyte concentrations are often low, and in the case of drugs, the endogenous compounds are sometimes structurally very similar to the drug to be measured. The binding of drugs to the plasma protein also may occur which decreases the amount of free compound that is measured. To undertake the analyses of drugs and metabolites in body fluids the analyst is facet with several problems. The first problem is due to the complex nature of the body fluid, the drugs must be isolated by an extraction technique, which ideally should provide a relatively clean extract, and the separation system must be capable of resolving the drugs of interest from co extractives. All mentioned when we are using high performance liquid chromatography require good selections of detectors, good stationary phase, eluents and adequate program during separation. UV/VIS detector is the most versatile detector used in high performance liquid chromatography it is not always ideal since it is lack of specificity means high resolution of the analyte that may be required. UV detection is preferred since it offers excellent linearity and rapid quantitative analyses can be performed against a single standard of the drug being determined. Diode array and rapid scanning detector are useful for peak identification and monitoring peak purity but they are somewhat less sensitive then single wavelength detectors. In liquid chromatography some components may have a poor UV chromophores if UV detection is being used or be completely retained on the liquid chromatography column. Fluorescence and electrochemical detector are not only considerably more sensitive towed appropriate analytes but also more selective than UV detectors for many compounds. If at all possible fluorescence detectors are sensitive, stable, selective and easy to operate. It is selectivity shows itself in the lack of frontal components observed in plasma extract whereas electrochemical detection is nearly always associated with a major frontal peak than tails considerably. To date, the most sensitive method has been the reductive electrochemical detection and giving the excellent results in the investigation on some classes of drugs. Several high performance liquid chromatography oxidative electrochemical methods have been developed for the analyses of drugs and metabolites in body fluids. Mass spectrometer as specific detector with all variation of ionisation and interface (thermo spray, moving belt etc. ) or liquid chromatography-tandem mass spectrometry2,3,4,5). NMR as selective and specific detector in high performance liquid chromatography today is also in used. The development of a non-aqueous eluent for ion-exchange separation on silica has provided an excellent system which, when used in conjugation with an electrochemical detector, permits the analyses of an extensive range of especially basic drugs and metabolites. New packing materials such as polymeric, base deactivated silica's, pyrolysed carbon and the internal surface packing should offer the improved stability and higher efficiencies for certain classes of the compounds such as basic drugs. Microbore columns should become more accepted since they offer not only improved sensitivity but also a lower solvent consumption and consequently the reduced needs to dispose of noxious solvents. Many analyses of basic drugs are still performed by the same method of the ion-exchange chromatography on unmodified silica columns with an eluent buffered to about pH 9. Neutral or weakly acidic drugs for instance barbiturates can be chromatographed on a reversed phase system whilst acidic drugs for example paracetamol, cannabis are separated either by ion suppression or ion-pair chromatography on a reversed-phase packing material. In micelar liquid chromatography micelar mobile phases in reversed-phase instead of conventional hydro organic mobile phase is used. In micelar liquid chromatography complex electrostatic hydrophobic and steric interactions exist between the solute and both stationary and mobile phases. These enable the effective separation of samples of different nature. The main advantages of the use of a micelar solution in reversed-phase liquid chromatography are the solvent and the lower cost and toxicity, the biodegradability of the solvent and the easy dissolution of analytical samples, that enables the determination of drugs in physiological fluids without the need for previous separation of the proteins present in the samples. Using tetrabutylammonium phosphate as a competing base in the investigation of sulphonamides and heptanes sulfonate as ion pairing reagent. Ion pairing reagent is term used to describe enhanced retention as the result of the addition to the mobile phase of a large ion opposite charge to the molecular ions to be separated. For molecular cations alkyl sulphates or sulfonates are generally utilised.

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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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Vardhan D, Vishnu, Venkateswar K, and Srinivas Nayak A. "DEVELOPMENT AND VALIDATION OF HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) METHOD FOR CANDESARTAN CILEXETIL IN PURE AND FORMULATION PRODUCTS." International Journal of Pharmacy and Biological Sciences 6, no. 4 (October 1, 2016): 35–41. http://dx.doi.org/10.21276/ijpbs.2016.6.4.5.

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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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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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Fan, Su Su, Jian Shi, Ling Yuan, Ling Zhou, and Zhi Peng Xu. "Chiral Separation of Cypermethrin Enantiomers by High Performance Liquid Chromatography." Advanced Materials Research 1073-1076 (December 2014): 417–22. http://dx.doi.org/10.4028/www.scientific.net/amr.1073-1076.417.

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The separation of cypermethrin was studied on Chiralcel OD-H column using the high performance liquid chromatography (HPLC) method. And well distinguished peaks of cypermethrin isomers were obtained. The influences of mobile phase ratios, flow rates, and detection wavelengths on the separation results were investigated. The optimal chromatographic conditions were as follows: the mobile phase ratio was hexane: isopropanol = 97:3, the flow rate was 0.4ml/min, and the wavelength was set as 236 nm. Under the optimal conditions, the resolutions of cypermethrin enantiomers were more than 2.0.

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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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Shim, Dae Hyun, Dong Han Shin, Quoc Ky Truong, Xuan Lan Mai, Jong-Seong Kang, Mi Hee Woo, Dong-Hee Na, In-Koo Chun, and Kyeong Ho Kim. "Development of high performance liquid chromatography assay method of diosmin capsules." Analytical Science and Technology 29, no. 6 (December 25, 2016): 277–82. http://dx.doi.org/10.5806/ast.2016.29.6.277.

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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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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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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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Schieppati, Dalma, Nicolas A. Patience, Sebastiano Campisi, and Gregory S. Patience. "Experimental methods in chemical engineering: High performance liquid chromatography—HPLC." Canadian Journal of Chemical Engineering 99, no. 8 (April 19, 2021): 1663–82. http://dx.doi.org/10.1002/cjce.24050.

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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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Fan, Su Su, Jian Shi, Ling Zhou, and Yu Wen Hang. "Analysis of Bifenthrin and its Enantiomer Using High Performance Liquid Chromatography." Applied Mechanics and Materials 675-677 (October 2014): 275–79. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.275.

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Using the high performance liquid chromatography (HPLC) method, bifenthrin isomers can be split at a polysaccharide derivatives chiral stationary phase column, and two well distinguished peaks of bifenthrin isomers are obtained. The effects of mobile phase ratios, temperatures, and detection wavelengths on the separation results are discussed. The optimal chromatographic conditions are as follows: the mobile phase ratio is methanol: ammonium acetate salts = 80:20, the column temperature is 35°C, and the wavelength is set as 220 nm. Under the optimal conditions, the resolution of bifenthrin enantiomer can be as large as 3.0.

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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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Supriyono, Supriyono, Mudhiah Fitrillah, and Arie Pratama Putra. "Validation of High-Performance Liquid Chromatography Method for Determination of Vitamin B1 in Powder Milk." Jurnal Kimia Sains dan Aplikasi 23, no. 5 (April 20, 2020): 177–82. http://dx.doi.org/10.14710/jksa.23.5.177-182.

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Vitamin B1 plays an important role in the co-enzymatic reactions for energy-rich compounds called ATP (Adenosine Tri Phosphate). Therefore, it should be added to various food products, for example, milk powder. One method that can be used to determine vitamin B1 is SNI number 3751: 2009, but the method is intended for wheat flour. If the method is to be used for the analysis from other samples, such as milk powder, optimization, and validation, are needed. This experiment was carried out using HPLC, C18 column, and UV detector with a wavelength of 254 nm. The mobile phase used is methanol: acetic acid: bi-distilled water = 32:1:67 (v/v/v), flow rate = 1 mL/minute, isocratic, and reverse phased technique. Method validation parameters include tests of system suitability, linearity, the limit of detection, the limit of quantitation, precision (repeatability), and accuracy. The results showed that the system suitability test was obtained relative standard deviations (% RSD) for retention time and peak area, tailing factor, resolution, separation factor was 0.297%, 1.476%, 1.113, 6.693, and 4.406 respectively. The validation test gets a correlation coefficient (R) of 0.9996, the limit of detection and limit of quantitation were 0.0122 mg/100 mL and 0.0244 mg/100 mL, respectively. The precision test obtained Horwitz's ratio of 0.27%. Accuracy test using CRM obtained % recovery of 93.79-97.77%. All these results meet the requirements of method validation, so it can be concluded that the method of SNI number 3751: 2009 is valid for the determination of vitamin B1 in milk powder and can be used for routine analysis procedure.

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Hasanzadeh, Mahsa, and Amir Heydari. "Evaluation of intraocular penetration of levofloxacin by high performance liquid chromatography." International Eye Research 2, no. 3 (September 28, 2021): 155–58. http://dx.doi.org/10.18240/ier.2021.03.07.

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AIM: To evaluate the levofloxacin eye drop into human eye penetration, levofloxacin eye drop concentrations in human ocular aqueous of 33 patients undergoing cataract surgery were measured by high performance liquid chromatography (HPLC). METHODS: Totally 33 volunteer patients who scheduled for phacoemulsification surgery received one drop of levofloxacin every 6h for 3d before and on the day of surgery, administration of drug was stopped 1h before surgery. Levofloxacin concentration in aqueous humor was measured by HPLC method with fluorescence detector. RESULTS: A simple, effective and sensitive HPLC method for determination of levofloxacin in human ocular aqueous was validated. Linearity was shown for levofloxacin concentration over a wide range of 1.95×10-3-1.50 µg/mL. The mean aqueous level of levofloxacin was 0.3399±0.03405 µg/mL. CONCLUSION: Results from the present study demonstrate that topical administration of levofloxacin 0.5% before cataract surgery with routine dose (one drop every 6h) unable to reach MIC90 for most common microorganism causing acute bacterial endophthalmitis.

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Lombard, Kevin A., Emmanuel Geoffriau, and Ellen Peffley. "Flavonoid Quantification in Onion by Spectrophotometric and High Performance Liquid Chromatography Analysis." HortScience 37, no. 4 (July 2002): 682–85. http://dx.doi.org/10.21273/hortsci.37.4.682.

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Direct spectrophotometric determination of quercetin content in onions (Allium cepa L.) was investigated as a possible alternative to high-performance liquid chromatography (HPLC) analysis. Quercetin content in five onion varieties was monitored at 362 nm and quantified using simple spectrophotometric and HPLC methods. HPLC revealed that 3,4'-Qdg and 4'-Qmg comprised up to 93% of total flavonol content detected in the studied varieties. These major quercetin conjugates combined (3,4'-Qdg + 4'-Qmg) and total flavonol conjugates quantified by HPLC correlated closely with spectrophotometer values. Correlation coefficients were 0.96 (P < 0.0001) for 3,4'-Qdg + 4'-Qmg and 0.97 (P < 0.0001) for total flavonol conjugates in onion. Simple spectrophotometric procedure proved to be a valid, efficient, and cost-effective method for the quantification of total quercetin in onion. Chemical names used: quercetin-3,4'-O-diglucoside (3,4'-Qdg); quercetin-4'-O-glucoside (4'-Qmg).

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Chen, Xiaoming, Chiyo Yamamoto, and Yoshio Okamoto. "Polysaccharide derivatives as useful chiral stationary phases in high-performance liquid chromatography." Pure and Applied Chemistry 79, no. 9 (January 1, 2007): 1561–73. http://dx.doi.org/10.1351/pac200779091561.

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The chromatographic separation of enantiomers using chiral stationary phases (CSPs) has significantly advanced. The esters and carbamates of polysaccharides coated on silica gel have been extensively studied and widely used as CSPs for high-performance liquid chromatography (HPLC). In order to overcome the strict solvent limitation on these coated CSPs, the preparation of a new generation of CSPs consisting of immobilized polysaccharide derivatives has become increasingly important. The universal solvent compatibility of the new CSPs provides flexibility in both analytical and preparative chromatographies.

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Zhuo, Yanli. "A Study on the Determination of Azithromycin by High-Performance Liquid Chromatography." Proceedings of Anticancer Research 5, no. 4 (July 29, 2021): 125–30. http://dx.doi.org/10.26689/par.v5i4.2368.

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Objective: To analyze the effect of high-performance liquid chromatography (HPLC) for the determination of azithromycin and to provide references for related research work. Methods: The mobile phase was ammonium dihydrogen phosphate at 0.067 mol/L (mixed with triethylamine; pH value was adjusted to 6.5). The chromatographic column was Kromasil C18 (250 mm × 4.6 mm; 5.0 ?m) and the relative standard deviation (RSD) of the drug content level was 1.25%. The injection volume was set to 20 ?L, the detection wavelength was set to 210 nm, the external standard method was used to complete the quantitative work, and the theoretical plate number should be more than 1000 according to the drug peak calculation. The effect of HPLC on the determination of azithromycin was analyzed. Results: The concentration of azithromycin was 1.40-3.40 mg/mL, and the linear relationship was good. RSD of the drug content level was 1.25%. The representative test product had strong stability within 8.0 hours and the method had good repeatability. According to the recovery experiment method, the recovery rates of three standard samples from low to high were 99.87%, 100.15%, and 100.62%. The average recovery rate was 100.21%. RSD value was 0.39%. It means that the recovery rate of HPLC is good. Conclusion: In the determination of azithromycin, the use of HPLC to complete the work was of high sensitivity, simple, and fast. The method had good repeatability in the determination of drug components which is worthy of further promotion.

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Acharya, Ruchi, Bhawna Sharma, Ruchi Singh, and Prabhat Jain. "Phytochemical and High-Performance Liquid Chromatography Analysis of Extract of Vernonia cinerea." Journal of Drug Delivery and Therapeutics 9, no. 1 (January 15, 2019): 229–32. http://dx.doi.org/10.22270/jddt.v9i1.2227.

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The present study aims to screen and quantify hydroalcoholic extract for phytochemical content and HPLC profiles for standardization. HPLC was carried out using a RP-C18 analytical column with a mobile phase composed of acetonitrile: methanol (50:50 v/v) and was isocratically eluted at a flow rate of 1 mL min-1. A small sample volume of 20 μL was used for each sample run, being injected into the HPLC system. The chromatogram was monitored with UV detection at a wavelength of 256 nm. Phytochemical screening of the extract showed the presence of flavonoids, amino acids, carbohydrates and protiens in hydroalcoholic extract. Quantification of total flavonoids showed that hydroalcoholic extract of Vernonia cinerea had flavonoid content 0.547 mg/100mg equivalent to quercetin. The data presented here could be used for the standardization of hydroalcoholic extract of Vernonia cinerea, either for future studies or in herbal drug formulations. Keywords: Vernonia cinerea, HPLC profiling, Phytochemical analysis, Hydroalcoholic extract.

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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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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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Gulnara G. Galyautdinova, Vladislav I. Egorov, Alexander M. Saifutdinov, Elvira R. Rakhmetova, Andrey V. Malanev, Damir V. Aleyev, Sergey Yu. Smolentsev, and Eduard I. Semenov. "Detection of tetracycline antibiotics in honey using high-performance liquid chromatography." International Journal of Research in Pharmaceutical Sciences 11, no. 1 (January 8, 2020): 311–14. http://dx.doi.org/10.26452/ijrps.v11i1.1822.

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It is hard to overestimate the value of honey since the constituent substances in it are of great importance in the food industry and medicine. The quality of honey is established by the legislation of the Russian Federation (GOST). But the levels of these standards are regulated by outdated methods of analysis, which can not give reliable results. The detection of antibiotic residues in honey is a central issue in the quality and safety control of this product. Accumulation of drugs in honey used to treat bee colonies can cause allergies and dysbiosis in people who have eaten such honey, as well as develop antibiotic resistance in microorganisms. At present, one of the promising directions in the field of detecting medicines in honey is the use of high-performance liquid chromatography (HPLC). It helps selectively and accurately detect antibiotic substances in honey bee products. In Russia, the HPLC method is used with mass spectrometry to detect tetracycline residues in honey. A significant drawback with this method that limits the widespread use of it is the application of expensive, technically sophisticated equipment that needs high-quality reagents and consumables. The purpose of this work was to develop the simultaneous identification of tetracycline antibiotics in honey and carry out their quantitative analysis by a reversed-phase HPLC method. A sample preparation algorithm was developed, and the conditions for chromatographing combined indication of tetracyclines in honey at an acceptable concentration according to the MRL (0.01 mg/kg) with Agilent 1260 Infiniti liquid chromatograph equipped with a column thermostat, a gradient pump, and a UV detector were selected. According to the results of the research, the most optimal condition for the simultaneous analysis of oxytetracycline, tetracycline hydrochloride, chlortetracycline in honey by HPLC method with ultraviolet detection was a wavelength of 254 nm, a flow rate of 0.5 ml/min and a column temperature of 25° C. Under these conditions, the antibiotic retention time was determined: 4.069 minutes for oxytetracycline, 4.331 minutes for tetracycline hydrochloride, 4.642 minutes for chlortetracycline. The developed HPLC method for the simultaneous determination of tetracycline antibiotics in honey was tested on honey bee products from the regions of the Republics of Tatarstan and Bashkortostan.

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Ragab, Marwa A. A., Mohamed H. Abdel-Hay, Hytham M. Ahmed, and Sara M. Mohyeldin. "Determination of Ibuprofen and Phenylephrine in Tablets by High-Performance Thin Layer Chromatography and in Plasma by High-Performance Liquid Chromatography with Diode Array Detection." Journal of Chromatographic Science 57, no. 7 (April 17, 2019): 592–99. http://dx.doi.org/10.1093/chromsci/bmz031.

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Abstract Two chromatographic methods (high performance thin layer chromatography (HPTLC) and high performance liquid chromatography–diode array detector (HPLC-DAD)), were addressed for the analysis of a mixture consisted of phenylephrine hydrochloride and ibuprofen in two forms bulk and their combined dosage form. This binary mixture is considered to be a challenging one as the two drugs differ greatly in their chemical and physical properties. Not only this affects their simultaneous analysis, but also hinders their simultaneous extraction from biological fluids as plasma. That is the reason the literature lacks any report for the simultaneous extraction and analysis of these drugs from biological fluids. The concentration ranges of both drugs were 0.1–2.5 μg/spot and 0.1–100 μg/mL by HPTLC and HPLC, respectively. Not only was the HPLC-DAD method applied to the investigated drugs determination in pharmaceutical preparations, but also in spiked human plasma. Extensive study was conducted to optimize their simultaneous extraction from plasma as it was a crucial step for the in vivo analysis. The results obtained by proposed methods and a reference one were statistically comparable by analysis of variance test. No significant difference was recorded between the mean percent levels determined by the proposed methods and the reference one.

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Kemmo, S., V. Ollilainen, Lampi A-M, and V. Piironen. "Determination of stigmasterol hydroperoxides using high-performance liquid chromatography-mass spectrometry with atmospheric pressure chemical ionization." Czech Journal of Food Sciences 22, SI - Chem. Reactions in Foods V (January 1, 2004): S144—S146. http://dx.doi.org/10.17221/10639-cjfs.

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A new specific method using high-performance liquid chromatography-mass spectrometry (HPLC-MS) for the detection of stigmasterol hydroperoxides was developed. Hydroperoxides of stigmasterol were obtained by photo-oxidation (90 min) in the presence of methylene blue as a sensitizer. The separation was performed using normal-phase chromatographic conditions. The MS detection was carried out with an ion-trap mass spectrometer using atmospheric pressure chemical ionization (APCI) and positive ion mode. Stigmasterol hydroperoxides were seen to produce no protonated molecular ions [M + H]+ but instead fragments representing loss of one or two water molecules [M – H2O + H]+, [M – 2H2O + H]+, loss of hydrogen peroxide [M – H2O2 + H]+ or loss of hydrogen peroxide and water [M – H2O2 – H2O + H]+. The results showed that positional isomers of hydroperoxides had different fragmentation patterns and relative ion abundances. On the other hand anomeric isomers had more similar fragmentation. As a conclusion the method developed showed to be a useful tool for investigation the oxidation mechanism of sterols.

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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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Zuo, Yong, Shuai Ju, Yang Li, Hui Xie, Li Ping Liu, Fang Min Wei, and An Guo Liu. "Applications of Reversed-Phase High-Performance Liquid Chromatoraphy in Strains Identification of the Bean Sprout." Advanced Materials Research 347-353 (October 2011): 354–59. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.354.

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Lactic acid which was fermented by bean sprout was determined and the lactobacillus in bean sprout was identified by High-performance Liquid Chromatoraphy(HPLC). The optimal HPLC chromatographic conditions were determined as follows:Agilent XDB-C18 chromatography column with UV detection at 210nm.The mobile phase was Phosphate buffer solution（pH=2.3）:methanol:acetonitrile（95%:2%:3%）.The flow rate was 0.5ml/min.This method is accurate,Speedily and reproducible. This method can identify the lactobacillus, and gives a qualitative and quantitative analysis of the lactic acid which was the metabolites of Yibin bean sprout.

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Yilmaz, Bilal, Kadem Meral, Ali Asci, and Yavuz Organer. "Determination of metoprolol in pure and pharmaceutical dosage forms by spectrofluorometry and high performance liquid chromatography." Chemical Industry and Chemical Engineering Quarterly 17, no. 1 (2011): 25–31. http://dx.doi.org/10.2298/ciceq100422047y.

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In this study, a new and rapid spectrofluorometry and high performance liquid chromatography (HPLC) methods were developed for determination of metoprolol in pure and pharmaceutical dosage forms. The solvent system, wavelength of detection and chromatographic conditions were optimized in order to maximize the sensitivity of both the proposed methods. The linearity was established over the concentration range of 50-4000 ng ml-1 for spectrofluorometry and 5.0-300 ng ml-1 for HPLC methods. The intra- and inter-day relative standard deviation (RSD) was less than 4.14 and 3.86% for spectrofluorometry and HPLC, respectively. Limit of quantitation was determined as 30 and 5.0 ng ml-1 for spectrofluorometry and HPLC, respectively. No interference was found from tablet excipients at the selected assay conditions. The methods were applied for the quality control of commercial metoprolol dosage forms to quantify the drug and to check the formulation content uniformity.

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Yoshimura, Manabu, Toshiaki Komori, Tadashi Nakanishi, and Hakuo Takahashi. "Estimation of Sulphoconjugated Catecholamine Concentrations in Plasma by High-Performance Liquid Chromatography." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 30, no. 2 (March 1993): 135–41. http://dx.doi.org/10.1177/000456329303000204.

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Free and sulphoconjugated catecholamine (CA) concentrations were measured in plasma using a fully automated and sensitive analyser equipped with a three-column system of high-performance liquid chromatography (HPLC). Although the free dopamine (DA) concentration has been below the detection limit of HPLC analysers thus far available, this new CA analyser can measure as little as 0·03 nmol/L. For the estimation of sulphoconjugated CA, we performed enzymatic deconjugation with arylsulphatase prior to HPLC analysis. The difference between free and total concentrations represents that of sulphoconjugated CA. The intraassay coefficient variation was less than 2·2% for free noradrenaline (NA) and adrenaline (A), 12·62% for free DA, and less than 4·3% for total A, and DA. These assays of free and sulphoconjugated CA are simple and can be performed routinely by a suitably equipped laboratory.

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Preti, Raffaella. "Core-Shell Columns in High-Performance Liquid Chromatography: Food Analysis Applications." International Journal of Analytical Chemistry 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/3189724.

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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.

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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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Ketchum, C. H., C. A. Robinson, and S. T. Huang. "Analysis of 8-methoxypsoralen by high-performance liquid chromatography." Clinical Chemistry 36, no. 11 (November 1, 1990): 1956–57. http://dx.doi.org/10.1093/clinchem/36.11.1956.

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Abstract We report a simple and rapid procedure for assaying 8-methoxypsoralen (8-MOP) in plasma by high-performance liquid chromatography (HPLC). The standard curve for the assay is linear for 8-MOP from 15 to 500 micrograms/L (y = 0.002x-0.01, r = 0.99) with a lower limit of detection of 1.5 micrograms/L. Intra-assay precision (CV) was 6.0% at the 100 micrograms/L concentration and 10.0% at 50 micrograms/L (n = 30 each). Interassay precision was 6.4% at 100 micrograms/L and 7.0% at 50 micrograms/L (n = 50 each). Extraction recovery of 8-MOP was 98%. Common antiarrhythmics, sedatives, and hypnotics were found not to interfere.

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Liu, Shu Yu, Li Jie Sun, and Xin Guo. "Determination of Stigmasterol in Jatropha Seed Oil by High Performance Liquid Chromatography." Advanced Materials Research 233-235 (May 2011): 1206–9. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.1206.

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A simple and rapid high performance liquid chromatography (HPLC) assay was developed to identify and measure the stigmasterol in jatropha seed oil. The stigmasterol was isolated with a good selectivity by HPLC employing reversed phase C18 columns. The components were separated by mobile phase of methanol-water (99/1, v/v) and detected at 202nm. The quantitation of the stigmasterol was reproducible and the method relative standard deviation is 1.6%. The mean analytical recovery was 97.0%．

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de Haro Moreno, Andréia, and Hérida Regina Nunes Salgado. "Development of a New High-Performance Liquid Chromatographic Method for the Determination of Ceftazidime." Journal of AOAC INTERNATIONAL 91, no. 4 (July 1, 2008): 739–43. http://dx.doi.org/10.1093/jaoac/91.4.739.

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Abstract A rapid, accurate, and sensitive high-performance liquid chromatographic (HPLC) method was developed and validated for the determination of ceftazidime in pharmaceuticals. The method validation parameters yielded good results and included range, linearity, precision, accuracy, specificity, and recovery. The excipients in the commercial powder for injection did not interfere with the assay. Reversed-phase chromatography was used for the HPLC separation on a Waters C18 (WAT 054275; Milford, MA) column with methanolwater (70 + 30, v/v) as the mobile phase pumped isocratically at a flow rate of 1.0 mL/min. The effluent was monitored at 245 nm. The calibration graph for ceftazidime was linear from 50.0 to 300.0 g/mL. The values for interday and intraday precision (relative standard deviation) were <1. The results obtained by the HPLC method were calculated statistically by analysis of variance. We concluded that the HPLC method is satisfactory for the determination of ceftazidime in the raw material and pharmaceuticals.

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Guermouche, M. H., D. Habel, and S. Guermouche. "Assay of Tinidazole in Human Serum by High-Performance Thin-Layer Chromatography—Comparison with High-Performance Liquid Chromatography." Journal of AOAC INTERNATIONAL 82, no. 2 (March 1, 1999): 244–47. http://dx.doi.org/10.1093/jaoac/82.2.244.

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Abstract Determination of tinidazole in human serum by high-performance thin-layer chromatography (HPTLC) is presented. It includes use of 10 × 10 cm plates coated with silica gel 60 and chloroform-acetonitrile-acetic acid (60 + 40 + 2) as mobile phase. Quantitation was performed by densitometry at 320 nm. The linearity (1-10 ng), precision (6%), reproducibility (5%), recovery (96%), and detection limit (1 mg/L) of tinidazole determination by HPTLC were comparable with corresponding method parameters by reversed-phase HPLC. A satisfactory correlation was found between the 2 analytical methods. The procedure was used to quantitate tinidazole in patient sera.

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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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Rittenhouse, Robert C. "HPLC for Windows: A Computer Simulation of High-Performance Liquid Chromatography." Journal of Chemical Education 72, no. 12 (December 1995): 1086. http://dx.doi.org/10.1021/ed072p1086.2.

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Lim, HoSoo, JungIm Kim, KyungYuk Ko, and Meehye Kim. "Determination of hexamethylenetetramine in foods by high-performance liquid chromatography (HPLC)." Food Additives & Contaminants: Part A 31, no. 9 (July 29, 2014): 1489–95. http://dx.doi.org/10.1080/19440049.2014.942706.

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Journal articles on the topic 'HPLC (high-performance liquid chromatography)'

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