A novel high performance liquid chromatographic method was developed for the determination of 4-O- methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation. Plasma samples were treated by o...A novel high performance liquid chromatographic method was developed for the determination of 4-O- methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation. Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins. A reverse phase column of SHIM- PACK VP-ODS （150 mm × 4.6 mm, 5.0 μm） was used to separate 4-O-methylhonokiol in the plasma samples. The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear range was 0. 012 - 1. 536 mg/L. The good extraction recoveries were obtained for the spiked samples （84.7%, 89.3% and 87.7% for low, middle and high concentrations of added standards, respectively）. The relative standard deviation of intra-day and inter-day precisions was in the range from 0.6% to 13.5%. The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasmaconcentration curve of 4-0-methylhonokiol showed a two-apartment open model. This work developed a sensitive, stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol.展开更多
Objective To study the pharmacokinetics of tamoxifen at a high dosage, which will offer a theoretical support for an appropriate clinical use of the medicine in non-small cell lung cancer (NSCLC) patients. Methods Thr...Objective To study the pharmacokinetics of tamoxifen at a high dosage, which will offer a theoretical support for an appropriate clinical use of the medicine in non-small cell lung cancer (NSCLC) patients. Methods Three qualified NSCLC patients are selected and given tamoxifen (TAM) 160 mg per Os. Blood samples were collected at different times and then analyzed by high-performance liguid chromatography. The PK-GRAPH program was used to obtain the parameters. Results The concentration-time courses of the TAM 160 mg were fitted to one-compartment model. The pharmacokinetic parameters were estimated as follows: Tmax (6.35±1.24)h, Cmax (217.39±7.71)ng/mL, AUC (12 127.39±636.16)ng·h/mL and T1/2ke (34.13±2.97)h. Conclusion TAM 160mg one day per Os cannot reach the effective maintenance concentration in vivo required for reversing MDR in vitro. Loading-maintenance dose strategy is recommended to study the pharmacodynamics of tamoxifen at a high dosage in NSCLC patients.展开更多
Aim To study the pharmacokinetics of oxiracetam after single and multipleintravenous administrations in healthy volunteers. Method A HPLC method was used to determine theserum concentration of oxiracetam after intrave...Aim To study the pharmacokinetics of oxiracetam after single and multipleintravenous administrations in healthy volunteers. Method A HPLC method was used to determine theserum concentration of oxiracetam after intravenous single dose and daily dose of 2 000 mg for 7 din ten Chinese healthy volunteers. Pharmacokinetic analysis was carried out using Drug And Statisticsoftware. Results The AUC_(0-12), AUC_(0-∞), K_e, t_(1/2), MRT after a single dose of 2 000 mgoxiracetam were 256.26 ± 16.84 μg·mL^(-1)·h, 276.74 ±18.11 μg·mL^(-1)·h, 0.18 ±0.03 h^(-1),3.84±0.64 h, and 4.39 10.39 h, and after multiple doses of oxiracetam were 259.36 ±25.43μg·mL^(-1)·h, 285.59 ±27.38 μg·mL^(-1)·h, 0.17 ±0.04 h^(-1), 4.14 ± 0.82 h, and 4.87 ±0.69 h, respectively. Conclusion The pharmacokinetic parameters of oxiracetam do not differremarkably after single and multiple intravenous administration and there is accumulation in serumafter 2 000 mg multiple intravenous administration once a day fof 7 d.展开更多
To test and study the Syndrome and Treatment Pharmacokinetics (S & TRK),we studied the pharmacokinetics of ferulic acid in healthy and blood stasis (microcirculation dysfunction)rabbits by RP-HPLC. After a single ...To test and study the Syndrome and Treatment Pharmacokinetics (S & TRK),we studied the pharmacokinetics of ferulic acid in healthy and blood stasis (microcirculation dysfunction)rabbits by RP-HPLC. After a single intravenous injection offenilic acid(5mg/kg)to healthy and blood stasis rabbits, compartment model of ferulic acid serum concentration was fitted and then pharmacokinetic parameters were calculated with a MCPKP program on a COMPAQ 386 compute Important parameters are as follows: In healthy rabbits V_B=0.9525±0.0211 L/kg,V_1=0.2462±0.0381 L/kg, CL_B=1.8133±0.9512 L/h·kg, T_(1/2β)=0.3639±0913, AUC=2.7566±0.8232 μg·h/ml; In blood stasis rabbits V_B=0.7882±0.0321 L/kg,V_1=0.1966±0.0537 L/kg,CL_B=0.8820±0.5481 L/h·kg,T_(1/2β)=0.6193±0.1216 h, AUC=5.6690±2.3541μg·h/ml.Through this experiment we found the sig-nificant differences in the FA's pharmacokinetic parameters between healthy and blood stasis rabbits.The results obtained correspond with S & TPK.展开更多
The objectives of the present study were to prepare stealthy etoposide proliposomes and study the pharmacokinetics in rabbits. Blank stealthy liposomes were prepared by film dispersion method. Stealthy etoposide lipos...The objectives of the present study were to prepare stealthy etoposide proliposomes and study the pharmacokinetics in rabbits. Blank stealthy liposomes were prepared by film dispersion method. Stealthy etoposide liposomes were prepared by using the ammonium sulfate gradient loading procedure. Vacuum freeze-drying technique was used to dry stealthy etoposide liposomes. Encapsulation efficiency of stealthy etoposide proliposomes was determined by Sephadex chromatography. The morphology was observed by transmission electronic microscope. The particle size and zeta potential were measured by using electrophoretic light scattering technology. The pharmacokinetics in rabbits was evaluated by comparison with etoposide injection and conventional liposomes, respectively. Mean encapsulation efficiency of stealthy etoposide proliposomes was 83.92% ± 3.65% （n = 3）. The liposomes were round or oval. Mean particle size was （124.5 ±26.9） nm, and zeta potential was （-39.50 ±1.04） mV. Following intravenous injection administration at a dose of 1.5 mg/kg etoposide, the three kinds of etoposide preparations were fitted with the two-compartment model. T1/2 β and A UC values of stealthy etoposide proliposomes were （19.26 ± 3.16） h and （26.04 ±3.53） μg/h/mL, respectively. T1/2 β and AUC values of etoposide injection were （0.94 ± 0.21） h and （0.98 ± 0.26） μg/h/mL, respectively. T1/2β and AUC values of conventional liposomes were （7.99 ± 1.36） h and （11.65 ± 1.70） μg/h/mL, respectively. Results indicated that the stealthy etoposide proliposomes could significantly extend the duration of etoposide in blood circulation.展开更多
The pharmacokinetics of oxiracetam and its degraded substance(4-hydroxy-2-oxo-1-pyrrolidine acetic acid,HOPAA)after oral and intravenous administration in rats were studied using an established UPLC-MS/MS method.Three...The pharmacokinetics of oxiracetam and its degraded substance(4-hydroxy-2-oxo-1-pyrrolidine acetic acid,HOPAA)after oral and intravenous administration in rats were studied using an established UPLC-MS/MS method.Three groups of rats after an overnight fasted received 10 g/kg(n=6)oxiracetam suspensions orally,and 2 g/kg(n=6)normal or degraded oxiracetam injections intravenously via a caudal tail vein,respectively.Before the pharmacokinetic experiment,a simple safety evaluation testwas conducted on the degraded oxiracetam injections containing 16.16% HOPAA in mice.There was no mortality by a single intravenous dose of 2 g/kg of degraded oxiracetam injections within twoweeks,demonstrating that HOPAA was non-toxic in mice.Following intravenous administration of the normal injections,the plasma concentration-time curves of oxiracetam and HOPAA both showed a rapid elimination phase.The values of t_(1/2)were 3.1±1.5 h for oxiracetamand 0.8±0.2 h for HOPAA,andthemean residencetimes(MRT)were 1.2±0.1h and 0.8±0.1h,respectively.Oxiracetam and HOPAA after intravenous administration of the degraded oxiracetam injections presented elimination patterns similar to those observed in the normal injections.Oral pharmacokinetic results showed that the Tmax was less than 1.5 h for the two analytes,and both had a longer t_(1/2) and MRT than those of intravenous administration.Contents of HOPAA in three groupswere calculated based on AUC_(0-t) values of the two analytes.The quantitative change of HOPAA in vivo was also evaluated by comparing the plasma concentrations of HOPAA and oxiracetamat the same time for every group.Additionally,the values of absolute bioavailability of oxiracetam were about 8.0%and 7.4%calculated by the normal or degraded oxiracetam injections,whichwere far less than the value of 75%reported in literature,indicating the necessity of further study.展开更多
基金supported by Xi'an Jiaotong University(No.01380011)
文摘A novel high performance liquid chromatographic method was developed for the determination of 4-O- methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation. Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins. A reverse phase column of SHIM- PACK VP-ODS （150 mm × 4.6 mm, 5.0 μm） was used to separate 4-O-methylhonokiol in the plasma samples. The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear range was 0. 012 - 1. 536 mg/L. The good extraction recoveries were obtained for the spiked samples （84.7%, 89.3% and 87.7% for low, middle and high concentrations of added standards, respectively）. The relative standard deviation of intra-day and inter-day precisions was in the range from 0.6% to 13.5%. The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasmaconcentration curve of 4-0-methylhonokiol showed a two-apartment open model. This work developed a sensitive, stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol.
基金This work was supported by grant from Science Investigation Fund of Ministry of Health of China(No96-1-250)
文摘Objective To study the pharmacokinetics of tamoxifen at a high dosage, which will offer a theoretical support for an appropriate clinical use of the medicine in non-small cell lung cancer (NSCLC) patients. Methods Three qualified NSCLC patients are selected and given tamoxifen (TAM) 160 mg per Os. Blood samples were collected at different times and then analyzed by high-performance liguid chromatography. The PK-GRAPH program was used to obtain the parameters. Results The concentration-time courses of the TAM 160 mg were fitted to one-compartment model. The pharmacokinetic parameters were estimated as follows: Tmax (6.35±1.24)h, Cmax (217.39±7.71)ng/mL, AUC (12 127.39±636.16)ng·h/mL and T1/2ke (34.13±2.97)h. Conclusion TAM 160mg one day per Os cannot reach the effective maintenance concentration in vivo required for reversing MDR in vitro. Loading-maintenance dose strategy is recommended to study the pharmacodynamics of tamoxifen at a high dosage in NSCLC patients.
文摘Aim To study the pharmacokinetics of oxiracetam after single and multipleintravenous administrations in healthy volunteers. Method A HPLC method was used to determine theserum concentration of oxiracetam after intravenous single dose and daily dose of 2 000 mg for 7 din ten Chinese healthy volunteers. Pharmacokinetic analysis was carried out using Drug And Statisticsoftware. Results The AUC_(0-12), AUC_(0-∞), K_e, t_(1/2), MRT after a single dose of 2 000 mgoxiracetam were 256.26 ± 16.84 μg·mL^(-1)·h, 276.74 ±18.11 μg·mL^(-1)·h, 0.18 ±0.03 h^(-1),3.84±0.64 h, and 4.39 10.39 h, and after multiple doses of oxiracetam were 259.36 ±25.43μg·mL^(-1)·h, 285.59 ±27.38 μg·mL^(-1)·h, 0.17 ±0.04 h^(-1), 4.14 ± 0.82 h, and 4.87 ±0.69 h, respectively. Conclusion The pharmacokinetic parameters of oxiracetam do not differremarkably after single and multiple intravenous administration and there is accumulation in serumafter 2 000 mg multiple intravenous administration once a day fof 7 d.
文摘To test and study the Syndrome and Treatment Pharmacokinetics (S & TRK),we studied the pharmacokinetics of ferulic acid in healthy and blood stasis (microcirculation dysfunction)rabbits by RP-HPLC. After a single intravenous injection offenilic acid(5mg/kg)to healthy and blood stasis rabbits, compartment model of ferulic acid serum concentration was fitted and then pharmacokinetic parameters were calculated with a MCPKP program on a COMPAQ 386 compute Important parameters are as follows: In healthy rabbits V_B=0.9525±0.0211 L/kg,V_1=0.2462±0.0381 L/kg, CL_B=1.8133±0.9512 L/h·kg, T_(1/2β)=0.3639±0913, AUC=2.7566±0.8232 μg·h/ml; In blood stasis rabbits V_B=0.7882±0.0321 L/kg,V_1=0.1966±0.0537 L/kg,CL_B=0.8820±0.5481 L/h·kg,T_(1/2β)=0.6193±0.1216 h, AUC=5.6690±2.3541μg·h/ml.Through this experiment we found the sig-nificant differences in the FA's pharmacokinetic parameters between healthy and blood stasis rabbits.The results obtained correspond with S & TPK.
基金Research Projects of Heilongjiang Science and Technology Department (Grant No.GC05C31601).
文摘The objectives of the present study were to prepare stealthy etoposide proliposomes and study the pharmacokinetics in rabbits. Blank stealthy liposomes were prepared by film dispersion method. Stealthy etoposide liposomes were prepared by using the ammonium sulfate gradient loading procedure. Vacuum freeze-drying technique was used to dry stealthy etoposide liposomes. Encapsulation efficiency of stealthy etoposide proliposomes was determined by Sephadex chromatography. The morphology was observed by transmission electronic microscope. The particle size and zeta potential were measured by using electrophoretic light scattering technology. The pharmacokinetics in rabbits was evaluated by comparison with etoposide injection and conventional liposomes, respectively. Mean encapsulation efficiency of stealthy etoposide proliposomes was 83.92% ± 3.65% （n = 3）. The liposomes were round or oval. Mean particle size was （124.5 ±26.9） nm, and zeta potential was （-39.50 ±1.04） mV. Following intravenous injection administration at a dose of 1.5 mg/kg etoposide, the three kinds of etoposide preparations were fitted with the two-compartment model. T1/2 β and A UC values of stealthy etoposide proliposomes were （19.26 ± 3.16） h and （26.04 ±3.53） μg/h/mL, respectively. T1/2 β and AUC values of etoposide injection were （0.94 ± 0.21） h and （0.98 ± 0.26） μg/h/mL, respectively. T1/2β and AUC values of conventional liposomes were （7.99 ± 1.36） h and （11.65 ± 1.70） μg/h/mL, respectively. Results indicated that the stealthy etoposide proliposomes could significantly extend the duration of etoposide in blood circulation.
基金This work was financially supported from the National Nature Science Foundation of China(No.81173009).
文摘The pharmacokinetics of oxiracetam and its degraded substance(4-hydroxy-2-oxo-1-pyrrolidine acetic acid,HOPAA)after oral and intravenous administration in rats were studied using an established UPLC-MS/MS method.Three groups of rats after an overnight fasted received 10 g/kg(n=6)oxiracetam suspensions orally,and 2 g/kg(n=6)normal or degraded oxiracetam injections intravenously via a caudal tail vein,respectively.Before the pharmacokinetic experiment,a simple safety evaluation testwas conducted on the degraded oxiracetam injections containing 16.16% HOPAA in mice.There was no mortality by a single intravenous dose of 2 g/kg of degraded oxiracetam injections within twoweeks,demonstrating that HOPAA was non-toxic in mice.Following intravenous administration of the normal injections,the plasma concentration-time curves of oxiracetam and HOPAA both showed a rapid elimination phase.The values of t_(1/2)were 3.1±1.5 h for oxiracetamand 0.8±0.2 h for HOPAA,andthemean residencetimes(MRT)were 1.2±0.1h and 0.8±0.1h,respectively.Oxiracetam and HOPAA after intravenous administration of the degraded oxiracetam injections presented elimination patterns similar to those observed in the normal injections.Oral pharmacokinetic results showed that the Tmax was less than 1.5 h for the two analytes,and both had a longer t_(1/2) and MRT than those of intravenous administration.Contents of HOPAA in three groupswere calculated based on AUC_(0-t) values of the two analytes.The quantitative change of HOPAA in vivo was also evaluated by comparing the plasma concentrations of HOPAA and oxiracetamat the same time for every group.Additionally,the values of absolute bioavailability of oxiracetam were about 8.0%and 7.4%calculated by the normal or degraded oxiracetam injections,whichwere far less than the value of 75%reported in literature,indicating the necessity of further study.
