Aim To develop a liquid chromatographic-tandem mass spectrometric (LC-MS-MS)method to determine clarithromycin in human plasma. Methods The analyte and internal standardroxithromycin were extracted from plasma samples...Aim To develop a liquid chromatographic-tandem mass spectrometric (LC-MS-MS)method to determine clarithromycin in human plasma. Methods The analyte and internal standardroxithromycin were extracted from plasma samples by n-nexane-dichloromethane-isopropanol(300:150:15, V/V/V) and chromalographed on a C_(18) column. The mobile phase consisted ofmethanol-water-formic acid (80 = 20:1, V/V/V) . Detection was performed on a triple quadrupoletandem mass spectrometer via electrospray ionization source (ESI) in the positive mode. Results Themethod had a lower limit of quantification of 10.0 ng·mL^(-1) when 0.2 mL plasma was used. Thelinear calibration curves were obtained in the concentration range of 10.0 - 5000 ng·mL^(-1) . Theintra- and inter-run precisions were lower than 3.3% in terms of relative standard deviation (RSD),and the accuracy ranged +- 0.7% in terms of relative error (RE). T_(max), C_(max), T_(1/2) andAUC_(0-24h), values were found to be (3.1 +- 2.7)h, (8 750+-4734) ng·mL^(-1), (5.3+-2.2) h, and(5932+-2449)ng·mL^(-1), respectively, after a single oral dose of 250 mg clarithromycin tablet to18 volunteers. Conclusion This validated method was successful in the evaluation of phaimacokineticprofiles of clarithromycin tablets administered to 18 healthy male volunteers.展开更多
Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical ...Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(< 10 k Da at 24 h). In summary, HP-chitosan has excellent bioavailability and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.展开更多
文摘Aim To develop a liquid chromatographic-tandem mass spectrometric (LC-MS-MS)method to determine clarithromycin in human plasma. Methods The analyte and internal standardroxithromycin were extracted from plasma samples by n-nexane-dichloromethane-isopropanol(300:150:15, V/V/V) and chromalographed on a C_(18) column. The mobile phase consisted ofmethanol-water-formic acid (80 = 20:1, V/V/V) . Detection was performed on a triple quadrupoletandem mass spectrometer via electrospray ionization source (ESI) in the positive mode. Results Themethod had a lower limit of quantification of 10.0 ng·mL^(-1) when 0.2 mL plasma was used. Thelinear calibration curves were obtained in the concentration range of 10.0 - 5000 ng·mL^(-1) . Theintra- and inter-run precisions were lower than 3.3% in terms of relative standard deviation (RSD),and the accuracy ranged +- 0.7% in terms of relative error (RE). T_(max), C_(max), T_(1/2) andAUC_(0-24h), values were found to be (3.1 +- 2.7)h, (8 750+-4734) ng·mL^(-1), (5.3+-2.2) h, and(5932+-2449)ng·mL^(-1), respectively, after a single oral dose of 250 mg clarithromycin tablet to18 volunteers. Conclusion This validated method was successful in the evaluation of phaimacokineticprofiles of clarithromycin tablets administered to 18 healthy male volunteers.
基金financially supported by National High Technology Research and Development Program of China(863 Program,Grant No.2007AA091603)
文摘Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(< 10 k Da at 24 h). In summary, HP-chitosan has excellent bioavailability and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.
