Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC-MS/MS, including (1) liquid-liquid extraction (LLE), (2) solid phase extraction (SPE) and ...Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC-MS/MS, including (1) liquid-liquid extraction (LLE), (2) solid phase extraction (SPE) and (3) supported liquid extraction (SLE). Comparison of recoveries of analytes with different extraction methods revealed that SLE was the best extraction method. The detection was facilitated with ion trap-mass spectrometer by multiple reactions monitoring (MRM) in a positive ion mode with ESI. The transitions monitored were m./z 441.1→325.2 for simvastatin, 408.2→235.1 for sitagliptin and 278.1→260.1 for the IS. The lower limit of quantification (LLOQ) was 0.2 ng/mL for sitagliptin and 0.1 ng/mL for simvastatin. The effective SLE offers enhanced chromatographic selectivity, thus facilitating the potential utility of the method for routine analysis of biological samples along with pharmacokinetic studies.展开更多
A novel bioanalytical method was developed and validated for the quantitative determination of darunavir(DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry(HILIC-MS...A novel bioanalytical method was developed and validated for the quantitative determination of darunavir(DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry(HILIC-MS/MS) with supported liquid extraction(SLE).lrbesartan(IRB) was used as an internal standard(IS).The analyte in rat plasma(200 μL) was isolated through SLE using ethyl acetate as the eluting solvent.The chromatographic separation was achieved on Luna-HILIC(250 mm × 4.6 mm,5 μm)column with a mobile phase of 0.1% of formic acid in water:acetonitrile(5:95,v/v),at a constant flow rate of 1.0mL/min.The MS/MS ion transitions for DRV(548.1→392.0) and IS(429.2→207.1) were monitored on an ion trap mass spectrometer,operating in the multiple reaction monitoring(MRM) mode.The lower limit of quantitation(LLOQ) was 0.2 ng/mL and quantitation range was 0.2-5000 ng/mL.The method was validated for its selectivity,sensitivity,carryover,linearity,precision,accuracy,recovery,matrix effect and stability.The method was successfully applied to pharmacokinetic study in rats.展开更多
A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liqu...A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liquid membrane was impregnated with different concentrations carrier.The experimental variables explored were concentration of yttrium(Ⅲ) ions,pH of source phase,PC-88A concentration in membrane phase,acid concentration in receiving phase and stirring speed.The pre-concentration of yttrium(Ⅲ) ions ...展开更多
文摘Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC-MS/MS, including (1) liquid-liquid extraction (LLE), (2) solid phase extraction (SPE) and (3) supported liquid extraction (SLE). Comparison of recoveries of analytes with different extraction methods revealed that SLE was the best extraction method. The detection was facilitated with ion trap-mass spectrometer by multiple reactions monitoring (MRM) in a positive ion mode with ESI. The transitions monitored were m./z 441.1→325.2 for simvastatin, 408.2→235.1 for sitagliptin and 278.1→260.1 for the IS. The lower limit of quantification (LLOQ) was 0.2 ng/mL for sitagliptin and 0.1 ng/mL for simvastatin. The effective SLE offers enhanced chromatographic selectivity, thus facilitating the potential utility of the method for routine analysis of biological samples along with pharmacokinetic studies.
文摘A novel bioanalytical method was developed and validated for the quantitative determination of darunavir(DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry(HILIC-MS/MS) with supported liquid extraction(SLE).lrbesartan(IRB) was used as an internal standard(IS).The analyte in rat plasma(200 μL) was isolated through SLE using ethyl acetate as the eluting solvent.The chromatographic separation was achieved on Luna-HILIC(250 mm × 4.6 mm,5 μm)column with a mobile phase of 0.1% of formic acid in water:acetonitrile(5:95,v/v),at a constant flow rate of 1.0mL/min.The MS/MS ion transitions for DRV(548.1→392.0) and IS(429.2→207.1) were monitored on an ion trap mass spectrometer,operating in the multiple reaction monitoring(MRM) mode.The lower limit of quantitation(LLOQ) was 0.2 ng/mL and quantitation range was 0.2-5000 ng/mL.The method was validated for its selectivity,sensitivity,carryover,linearity,precision,accuracy,recovery,matrix effect and stability.The method was successfully applied to pharmacokinetic study in rats.
基金supported by Department of Science and Technology,Government of India (GAP 271526)
文摘A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liquid membrane was impregnated with different concentrations carrier.The experimental variables explored were concentration of yttrium(Ⅲ) ions,pH of source phase,PC-88A concentration in membrane phase,acid concentration in receiving phase and stirring speed.The pre-concentration of yttrium(Ⅲ) ions ...