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High Performance Liquid Chromatographic Method (high + performance_liquid_chromatographic_method)
Selected AbstractsHigh performance liquid chromatographic method for the determination and pharmacokinetic studies of oxyresveratrol and resveratrol in rat plasma after oral administration of Smilax china extractBIOMEDICAL CHROMATOGRAPHY, Issue 4 2008Huilian Huang Abstract A sensitive and simple HPLC method has been developed and validated for the determination of oxyresveratrol (trans -2,4,3,,5,-tetrahydroxystilbene, OXY) and resveratrol (trans -3,5,4,-trihydroxystilbene, RES) in rat plasma. The plasma samples were extracted with ethyl acetate and analyzed using HPLC on an Aglient Zorbax SB-C18 column (250 × 4.6 mm, 5 µm) at a wavelength 320 nm, with a linear gradient of (A) acetonitrile and (B) 0.5% aqueous acetic acid (v/v), at a flow rate of 1.0 mL/min. The method was linear over the range of 0.1265,25.3 µg/mL for OXY and 0.117,23.4 µg/mL for RES. The extraction recovery for OXY, RES and internal standard ranged from 71.1 to 88.3%. The intra- and inter-day precisions were better than 10%, and the accuracy ranged from 89 to 108%. The validated method was used to study the pharmacokinetic profiles of OXY and RES in rat plasma after oral administration of Smilax china root extract. Copyright © 2007 John Wiley & Sons, Ltd. [source] Silica-based monolithic column with evaporative light scattering detector for HPLC analysis of bacosides and apigenin in Bacopa monnieriJOURNAL OF SEPARATION SCIENCE, JSS, Issue 15-16 2009Pamita Bhandari Abstract A high performance liquid chromatographic method using a silica-based monolithic column coupled with evaporative light scattering detector (HPLC,ELSD) was developed and validated for simultaneous quantification of bacosides (bacoside A, bacopaside I, bacoside A3, bacopaside II, bacopaside X, bacopasaponin C) and apigenin in Bacopa monnieri. The chromatographic resolution was achieved on a Chromolith RP-18 (100×4.6 mm) column with acetonitrile/water (30:70) as mobile phase in isocratic elution at a flow rate of 0.7 mL/min. The drift tube temperature of the ELSD was set to 95°C, and the nitrogen flow rate was 2.0 SLM (standard liter per minute). The calibration curves revealed a good linear relationship (r2 >0.9988) within the test ranges. The detection limits (S/N = 3) and the quantification limits (S/N = 10) for the compounds were in the range of 0.54,6.06 and 1.61,18.78 ,g/mL, respectively. Satisfactory average recovery was observed in the range of 95.8,99.0%. The method showed good reproducibility for the quantification of these compounds in B. monnieri with intra- and inter-day precision of less than 0.69 and 0.67%, respectively. The validated method was successfully applied to quantify analytes in nine accessions of B. monnieri and thus provides a new basis for overall quality assessment of B. monnieri. [source] Validated liquid chromatographic method for quantitative determination of allicin in garlic powder and tabletsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 16 2007Marta de Diego Abstract In the present study, an RP high performance liquid chromatographic method was developed and validated for the determination of allicin in garlic powder and tablets. Chromatographic separation was carried out on an RP-18e column (125 mm×4 mm), using a mobile phase, consisting of methanol,water (50:50 v/v), at a flow rate of 0.5 mL/min and UV detection at 220 nm. Ethylparaben was used as the internal standard. The assay was linear for allicin concentrations of 5.0,60.0 ,g/mL. The RSD for precision was <6.14%. The accuracy was above 89.11%. The detection and quantification limits were 0.27 and 0.81 ,g/mL, respectively. This method was used to quantify allicin in garlic powder samples. The results showed that the method described here is useful for the determination of allicin in garlic powder and tablets. [source] Development and validation of a stereoselective HPLC method for the determination of the in vitro transport of nateglinide enantiomers in rat intestineJOURNAL OF SEPARATION SCIENCE, JSS, Issue 12 2007Srinivas Maddi Abstract A simple stereoselective high performance liquid chromatographic method was developed for the determination of the in vitro transport of the enantiomers of nateglinide (N -(trans -4-isopropylcyclohexyl-carbonyl)-phenylalanine) in the rat intestine using a Chiralcel OJ-RH column (150×4.0 mm, 5 ,m). The effects of the mobile phase composition, pH, the flow rate, and the temperature on the chromatographic separation were investigated. The enantioseparation was achieved at 33°C using a mobile phase containing 100 mM potassium dihydrogen phosphate, pH 2.5, and ACN (32:68 v/v) delivered at a flow rate of 1 mL/min. The analytes were monitored at 210 nm and linearity (r >0.99) was obtained for a concentration range of 0.5,50 ,g/mL. The LOD and LOQ were 0.2 and 0.5 ,g/mL for the R -enantiomer and 0.2 and 0.8 ,g/mL for the S -enantiomer, respectively. Both, the intra- and interday accuracy and precision of the calibration curves were determined. The method was successfully applied to estimate the in vitro passage of the enantiomers and the racemate of nateglinide in duodenum, jejunum, and ileum of rats. Generally, higher concentrations of nateglinide and the S -enantiomer were observed when the racemate was administered compared to administration of the individual enantiomers of nateglinide. [source] Bioavailability and pharmacokinetics of florfenicol in broiler chickensJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2003J. Shen The bioavailability and pharmacokinetic disposition of florfenicol in broiler chickens were investigated after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 15 and 30 mg/kg body weight (b.w.). Plasma concentrations of florfenicol were determined by a high performance liquid chromatographic method in which plasma samples were spiked with chloramphenicol as internal standard. Plasma concentration,time data after i.v. administration were best described by a two-compartment open model. The elimination half-lives were 168 ± 43 and 181 ± 71 min, total body clearance 1.02 ± 0.17 and 1.02 ± 0.16 L·kg/h, the volume of distribution at steady-state 4.99 ± 1.11 and 3.50 ± 1.01 L/kg after i.v. injections of 15 and 30 mg/kg b.w., respectively. Plasma concentration,time data after i.m. and oral administrations were adequately described by a one-compartment model. The i.m. bioavailability and the oral bioavailability of florfenicol were 95, 98 and 96, 94%, respectively, indicating that florfenicol was almost absorbed completely after i.m. and oral administrations of 15 and 30 mg/kg b.w. [source] Simultaneous determination of albi,orin and paeoni,orin in rat urine by solid-phase extraction and high-performance liquid chromatography following oral administration of Si,Wu decoctionBIOMEDICAL CHROMATOGRAPHY, Issue 10 2004Yuxin Sheng Abstract A high performance liquid chromatographic method (HPLC), together with solid phase extraction (SPE), was developed for simultaneous determination of albi,orin and paeoni,orin in rat urine after oral administration of Si,Wu decoction. The samples were pretreated with solid phase extraction using Extract-CleanÔ cartridges. Analysis of the extract was performed on a reversed-phase C18 column and a mobile phase made up of acetonitrile and 0.03% formic acid (17:83, v/v). UV detection was set at 230 nm. The assay was linear over the range 2.625,52.50 mg/mL for albi,orin and 3.875,77.50 µg/mL for paeoni,orin. The average percentage recoveries of three spiked urines were 97.01 ± 3.32 and 102.32 ± 6.97 for albi,orin and paeoni,orin, respectively. The intra-day precision (RSD) ranged from 0.21 to 1.79% at concentrations of 4.20, 10.50, 26.25 and 39.375 µg/mL of albi,orin and 0.12 to 2.92% at concentrations of 3.875, 10.85, 23.25 and 58.125 µg/mL of paeoni,orin, and inter-day precision (RSD) was from 1.02 to 1.86% for albi,orin and 0.94 to 3.30% for paeoni,orin, at the same four concentrations. This method was applied in order to analyze albi,orin and paeoni,orin in rat urine following oral administration of traditional Chinese medicinal preparation of Si,Wu decoction. Copyright © 2004 John Wiley & Sons, Ltd. [source] Simultaneous determination of nicotinamide, pyridoxine hydrochloride, thiamine mononitrate and riboflavin in multivitamin with minerals tablets by reversed-phase ion-pair high performance liquid chromatographyBIOMEDICAL CHROMATOGRAPHY, Issue 8 2002Ke Li A reversed-phase ion-pair high performance liquid chromatographic method (HPLC) has been developed and validated for the routine analysis of nicotinamide, pyridoxine hydrochloride, thiamine mononitrate and riboflavin in multivitamin with minerals tablets. HPLC separation of the vitamins was performed on a Hypersil C18 column and detected by ultraviolet absorbance at 280,nm. The use of methanol-aqueous 0.5% acetic acid solution (18:82, v/v; containing 2.5,mM sodium hexanesulfonate, pH,=,2.8) as the mobile phase at a flow-rate of 1.2,mL/min enables the baseline separation of the four analytes free from interferences with isocratic elution at 30°C. The analysis time was 17,min per injection. The method was linear in the ranges of 5,90, 2.5,90, 5,95 and 25,450,µg/mL for thiamine mononitrate, riboflavin, pyridoxine hydrochloride and nicotinamide, respectively. The average coefficients of variation of within- and between-day assays were 2.2 and 3.6% for thiamine mononitrate, 1.8 and 2.4% for riboflavin, 1.3 and 1.7% for pyridoxine hydrochloride and 1.0 and 1.5% for nicotinamide, respectively. The average recoveries of thiamine mononitrate, riboflavin, pyridoxine hydrochloride and nicotinamide were 97.0, 97.2, 98.9 and 100.4% for the tablets, respectively. The method has been successfully applied to the simultaneous determination of nicotinamide, pyridoxine hydrochloride, thiamine mononitrate and riboflavin in multivitamin with minerals tablets. Copyright © 2002 John Wiley & Sons, Ltd. [source] Determination of bevantolol enantiomers in human plasma by coupled achiral,chiral high performance-liquid chromatographyCHIRALITY, Issue 7 2007Joung Weon Oh Abstract A coupled achiral,chiral high performance liquid chromatographic method was developed and fully validated for the determination of bevantolol enantiomers, (,)-(S)-bevantolol and (+)-(R)-bevantolol, in human plasma. Plasma samples were prepared by solid phase extraction with Sep-Pak Plus C18 cartridges followed by HPLC. Bevantolol enantiomers and (+)-(R)-Propranolol as internal standard (IS) were preseparated from interfering components in plasma on a Phenomenex silica column and bevantolol enantiomers and IS were resolved and determined on a Chiralcel OJ-H chiral stationary phase. The two columns were connected by a switching valve equipped with silica precolumn. The Precolumn was used to concentrate bevantolol in the eluent from the achiral column before back flushing onto chiral phase. A detailed validation of the method was performed accordingly to FDA guidelines. For each enantiomer the assay was linear between 20 and 1600 ng/ml. The quantification limits of both bevantolol enantiomers were 20 ng/ml. The intraday variation was between 1.07 and 12.64% in relation to the measured concentration and the interday variation was 0.91 and 11.79%. The method has been applied to the determination of (,)-(S)- and (+)-(R)-bevantolol in plasma from healthy volunteers dosed with racemic bevantolol hydrochloride. hydrochloride. Chirality, 2007. © 2007 Wiley-Liss, Inc. [source] | ||||||||||