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ODS C18 Column (ods + c18_column)
Selected AbstractsSimultaneous determination of 11 saponins in Panax notoginseng using HPLC-ELSD and pressurized liquid extractionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 14 2006Jian-Bo Wan Abstract A new HPLC coupled with evaporative light scattering detection (ELSD) method was developed for simultaneous determination of 11 major triterpene saponins, namely notoginsenoside R1 (1), ginsenosides Rg1 (2), Re (3), Rf (4), Rb1 (5), Rg2 (6), Rc (7), Rb2 (8), Rb3 (9), Rd (10), and Rg3 (11) in Panax notoginseng, a commonly used traditional Chinese medicine (TCM). Pressurized liquid extraction (PLE) was employed for sample preparation, and the analysis was achieved using a Zorbax ODS C18 column eluted with gradient water-ACN in 60 min. The drift tube temperature of ELSD was set at 60°C, and nitrogen flowrate was at 1.4 L/min. The method provided good repeatability and sensitivity for quantification of 11 saponins with overall precision (including intra- and interday) and LOD of less than 2.9% (RSD) and 98 ng, respectively. The validated method was successfully applied to quantify 11 saponins in 28 samples of P. notoginseng collected in different places, which is helpful to control the quality of P. notoginseng and its related products. [source] Development and validation of a HPLC method for determination of levonorgestrel and quinestrol in rat plasmaBIOMEDICAL CHROMATOGRAPHY, Issue 7 2010Tao Tang Abstract Levonorgestrel and quinestrol, commonly known as EP-1, has long been used in the control of wild rodents. Up to the present time, however, no method for simultaneous quantification of levonorgestrel and quinestrol in rat plasma has been reported. In the present study, a sensitive reverse-phase high-performance liquid chromatography with ultraviolet detection (RP-HPLC-UV) method for quantification of levonorgestrel and quinestrol in rat plasma has been developed. It uses a Kromasil ODS C18 column and acetonitrile-0.1% formic acid (85,:,15, v/v) mobile phase at ambient temperature. The plasma sample was prepared by hexane,isoamyl alcohol extraction (90,:,10, v/v). The flow rate and detection wavelength were 1.0,mL/min and 230,nm. The correlation coefficients were greater than 0.9995 within 0.08,50,,g/mL for levonorgestrel and 0.12,50,,g/mL for quinestrol, and the limits of detection were 0.02 and 0.05,,g/mL for levonorgestrel and quinestrol, respectively. Average recovery ranged from 92.5 to 96.3% and inter-day RSDs were less than 7.56%. This method can be applied to the further pharmacokinetic study of levonorgestrel and quinestrol in rat plasma. Copyright © 2009 John Wiley & Sons, Ltd. [source] A simple RP-HPLC method for quantification of columbianadin in rat plasma and its application to pharmacokinetic studyBIOMEDICAL CHROMATOGRAPHY, Issue 4 2010You-Bo Zhang Abstract A rapid and sensitive reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed to investigate pharmacokinetics of columbianadin, one of the main bioactive constituents in the roots of Angelica pubescens f. biserrata, in rat plasma after intravenous administration to rats at two doses of 10 and 20,mg/kg. The method involves a plasma clean-up step using liquid,liquid extraction by diethyl ether, followed by RP-HPLC separation and detection. Separation of columbianadin was performed on an analytical DiamonsilÔ ODS C18 column, with a mobile phase of MeOH,H2O (85,:,15, v/v) at a flow-rate of 1.0,mL/min, and UV detection was set at 325,nm. The retention time of columbianadin and scoparone (internal standard) was 6.7 and 3.5,min, respectively. The calibration curve was linear over the range of 0.2,20.0,,g/mL (r2 = 0.9986) in rat plasma. The lower limits of detection and quantification were 0.05 and 0.1,,g/mL, respectively. The extraction recovery from plasma was in the range of 81.61,89.93%. The intra- and inter-day precisions (relative standard deviation) were between 1.01 and 9.33%, with accuracies ranging from 89.76 to 109.22%. The results indicated that the method established was suitable for the determination and pharmacokinetic study of columbianadin in rat plasma. Copyright © 2009 John Wiley & Sons, Ltd. [source] Concurrent determination of thalidomide in rat blood, brain and bile using multiple microdialysis coupled to liquid chromatographyBIOMEDICAL CHROMATOGRAPHY, Issue 7 2005Yu-Jen Huang Abstract A rapid and sensitive system of liquid chromatography coupled with microdialysis was developed for the simultaneous determination of unbound thalidomide in rat blood, brain and bile for pharmacokinetic study. Microdialysis probes were concurrently inserted into the jugular vein toward the right atrium, the brain striatum and the bile duct of the anesthetized Sprague,Dawley rats for biological ,uid sampling after the administration of thalidomide (5 mg kg,1) through the femoral vein. Thalidomide and dialysates were separated using a Zorbax ODS C18 column and a mobile phase comprising acetonitrile,methanol,0.1 mm 1-octanesulufonic acid (32:3:65, v/v/v, pH 5.3) at ,ow rate of 1 mL min,1. The UV wavelength was set at 220 nm. The concentration,response relationship was linear (r2 > 0.995) over a concentration range of 0.025,25 µg mL,1. The intra-assay and inter-assay precision and accuracy of thalidomide fell within 7%. The average in vivo recoveries were 0.31 ± 0.02,0.046 ± 0.004 and 0.57 ± 0.02 (n = 6), respective to the dialysates of blood, brain and bile, with thalidomide at concentrations 2, 5 and 10 µg mL,1. The disposition of thalidomide in the blood, brain and bile ,uid suggests that there is a rapid thalidomide exchange and equilibration between the blood and brain systems. In addition, thalidomide undergoes hepatobiliary excretion. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||