The pharmacokinetics of 16-dehydropregnenolone （16-DHP）, a sterols compound isolated from Solanum lyratum Thunb., was investigated in rats following a single intramuscular administration （40 mg/kg）. The concentrat...The pharmacokinetics of 16-dehydropregnenolone （16-DHP）, a sterols compound isolated from Solanum lyratum Thunb., was investigated in rats following a single intramuscular administration （40 mg/kg）. The concentration of 16-DHP in rat plasma was determined by a high performance liquid chromatography （HPLC） method with UV detection. Levonorgestrel was used as the internal standard （IS）. The pharmacokinetic parameters of 16-DHP were derived by non-compartmental method. After a single intramuscular administration, the maximum plasma concentration （Cmax） was （289±25）ng/mL, time to reach Cmax（tmax） was （0.38±0.14） h, the elimination half-life （t1/z） was （2.5±1.1）h, the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration （AUC（0-t）） was （544± 73）ng· h/mL. The results indicated that 16-DHP was absorbed quickly and eliminated rapidly in rats after the intramuscular injection.展开更多
A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulatio...A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulations(injections,capsules and tablets)without any pretreatment or derivatization step.Azithromycin,degradation products and formulation ingredients were separated efficiently by using the mobile phase consisted of ammonium acetate(0.05 M,pH 8.0)and acetonitrile(60:40,v/v)in an isocratic mode at 0.8 ml/min flow rate.Parameters of ELSD were 60C for evaporation temperature and 50 psi for pressure of carrier gas(air).A logarithmic calibration curve was obtained from 50.93 to 509.30 mg/ml(r¼0.9996)for azithromycin,with the limit of detection(LOD)of 6.75 mg/ml(S/n¼3)and the limit of quantification of 22.50 mg/ml(S/n¼10).The developed method was validated and applied with satisfactory accuracy and precision for the determination of azithromycin in raw materials and pharmaceutical formulations(recovery 99e102%,RSD<1.2%,n¼3).No significant difference(t-test)was found between the results of the developed HPLCeELSD method and the HPLCeUV or microbiological method.展开更多
基金supported by the Science and Technolog Department of Liaoning Province(No.2007226011)Shenyang Office of Science and Technology(No.10711649-00)
文摘The pharmacokinetics of 16-dehydropregnenolone （16-DHP）, a sterols compound isolated from Solanum lyratum Thunb., was investigated in rats following a single intramuscular administration （40 mg/kg）. The concentration of 16-DHP in rat plasma was determined by a high performance liquid chromatography （HPLC） method with UV detection. Levonorgestrel was used as the internal standard （IS）. The pharmacokinetic parameters of 16-DHP were derived by non-compartmental method. After a single intramuscular administration, the maximum plasma concentration （Cmax） was （289±25）ng/mL, time to reach Cmax（tmax） was （0.38±0.14） h, the elimination half-life （t1/z） was （2.5±1.1）h, the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration （AUC（0-t）） was （544± 73）ng· h/mL. The results indicated that 16-DHP was absorbed quickly and eliminated rapidly in rats after the intramuscular injection.
基金National Natural Science Foundations of China(No.81173024)to professor Qiang Fu is gratefully acknowledged.The authors also thank Xi’an Insti-tute of Food and Drug Control for providing the facilities and necessary equipments.
文摘A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulations(injections,capsules and tablets)without any pretreatment or derivatization step.Azithromycin,degradation products and formulation ingredients were separated efficiently by using the mobile phase consisted of ammonium acetate(0.05 M,pH 8.0)and acetonitrile(60:40,v/v)in an isocratic mode at 0.8 ml/min flow rate.Parameters of ELSD were 60C for evaporation temperature and 50 psi for pressure of carrier gas(air).A logarithmic calibration curve was obtained from 50.93 to 509.30 mg/ml(r¼0.9996)for azithromycin,with the limit of detection(LOD)of 6.75 mg/ml(S/n¼3)and the limit of quantification of 22.50 mg/ml(S/n¼10).The developed method was validated and applied with satisfactory accuracy and precision for the determination of azithromycin in raw materials and pharmaceutical formulations(recovery 99e102%,RSD<1.2%,n¼3).No significant difference(t-test)was found between the results of the developed HPLCeELSD method and the HPLCeUV or microbiological method.
