To compare pharmacokinetic behaviors of nitrendipine submicron emulsion with nitrendipine solution following intravenous administration in rats.The plasma concentrations were analyzed by ultra-performance liquid chrom...To compare pharmacokinetic behaviors of nitrendipine submicron emulsion with nitrendipine solution following intravenous administration in rats.The plasma concentrations were analyzed by ultra-performance liquid chromatography coupled with tandem mass spectrometry detection(UPLC-MS/MS)through a new validated method.The pharmacokinetic parameters of the nitrendipine submicron emulsion and nitrendipine solution were as follows:AUC_(0-t) 900.76±186.59 versus 687.08±66.24 ng h/ml,C_(max) 854.54±159.48 versus 610.59±235.99 ng/ml,t_(1/2)2.37±1.99 versus 2.80±2.69 h.The relative bioavailability of nitrendipine submicron emulsion to nitrendipine solution was 131.4±11.3%.The developed methods could meet the requirements of bioanalysis.Compared to the solution injection,intravenous submicron emulsion presents higher systematic exposure which can help to improve the therapeutic efficacy.展开更多
The enantiomers separation of ei ght pharmaceutical racemates collected in Chinese Pharmacopoeia 2010(Ch.P2010),including nitrendipine,felodipine,omeprazole,praziquantel,sulpiride,clenbuterol hydrochloride,verapamil h...The enantiomers separation of ei ght pharmaceutical racemates collected in Chinese Pharmacopoeia 2010(Ch.P2010),including nitrendipine,felodipine,omeprazole,praziquantel,sulpiride,clenbuterol hydrochloride,verapamil hydrochloride and chlorphenamine maleate,was performed on chiral stationary phase of amylose ramification by high performance liquid chromatography(HPLC)on Chiralpak AD-H column and Chiralpak AS-H column with the mobile phase consisted of isopropanol and n-hexane.The detection wavelength and the flow rate were set at 254 nm and 0.7 mL/min,respectively.The effects of proportion of organic additives,alcohol displacer and temperature on the separation were investigated.The results indicated that eight chiral drugs were separated on chiral stationary phase of amylase ramification in normal phase chroma tographic system.The chromatographic retention and resolution of enantiomers were adjusted by factors,including the changes of the concentration of alcohol displacer in mobile phase,organic alkaline modifier and column temperature.It was shown that the resolution was improved with reducing concentration of alcohol displacer.When the concentration of organic alkaline modifier was 0.2%,the resolution and the peak shape were fairly good.Most racemates mentioned above had the best resolution at column temperature of 25℃.The best temperature should be kept unchanged in the process of separation so as to obtain stable separation results.展开更多
文摘To compare pharmacokinetic behaviors of nitrendipine submicron emulsion with nitrendipine solution following intravenous administration in rats.The plasma concentrations were analyzed by ultra-performance liquid chromatography coupled with tandem mass spectrometry detection(UPLC-MS/MS)through a new validated method.The pharmacokinetic parameters of the nitrendipine submicron emulsion and nitrendipine solution were as follows:AUC_(0-t) 900.76±186.59 versus 687.08±66.24 ng h/ml,C_(max) 854.54±159.48 versus 610.59±235.99 ng/ml,t_(1/2)2.37±1.99 versus 2.80±2.69 h.The relative bioavailability of nitrendipine submicron emulsion to nitrendipine solution was 131.4±11.3%.The developed methods could meet the requirements of bioanalysis.Compared to the solution injection,intravenous submicron emulsion presents higher systematic exposure which can help to improve the therapeutic efficacy.
文摘The enantiomers separation of ei ght pharmaceutical racemates collected in Chinese Pharmacopoeia 2010(Ch.P2010),including nitrendipine,felodipine,omeprazole,praziquantel,sulpiride,clenbuterol hydrochloride,verapamil hydrochloride and chlorphenamine maleate,was performed on chiral stationary phase of amylose ramification by high performance liquid chromatography(HPLC)on Chiralpak AD-H column and Chiralpak AS-H column with the mobile phase consisted of isopropanol and n-hexane.The detection wavelength and the flow rate were set at 254 nm and 0.7 mL/min,respectively.The effects of proportion of organic additives,alcohol displacer and temperature on the separation were investigated.The results indicated that eight chiral drugs were separated on chiral stationary phase of amylase ramification in normal phase chroma tographic system.The chromatographic retention and resolution of enantiomers were adjusted by factors,including the changes of the concentration of alcohol displacer in mobile phase,organic alkaline modifier and column temperature.It was shown that the resolution was improved with reducing concentration of alcohol displacer.When the concentration of organic alkaline modifier was 0.2%,the resolution and the peak shape were fairly good.Most racemates mentioned above had the best resolution at column temperature of 25℃.The best temperature should be kept unchanged in the process of separation so as to obtain stable separation results.
