Determination of Cefdinir Concentration in Rat Plasma by High Performance Capillary Electrophoresis and Its Pharmacokinetics Research / 中国药房

OBJECTIVE:To determine the concentration of cefdinir in rat plasma,and investigate its pharmacokinetics. METH-ODS:High performance capillary electrophoresis (HPCE) was adopted by using fused-silica capillary (75 μm,total length of 30 cm,effective length of 21.5 cm),buffer solution of 20 mmol/L citric acid,injection voltage of 10 kV for 10 s,separation voltage of -20 kV,and detection wavelength of 214 nm. 6 rats were intragastrically received cefdinir solution(20 mg/kg). 0.2 mL blood sample was taken from the tail vein before and 0.25,0.5,1,1.5,2,3,4,6,12,24 h after administration. BAPP 2.0 software was used to calculate the pharmacokinetics parameters. RESULTS:The linear range of cedinir ranged 0.2-50 μg/mL(r=0.9997), lower limit of quantification was 0.2 μg/mL. The intra-day(n=6)and inter-day RSDs of(n=3)precision test were no more than 12.2%;RSD of stability test was no more than 9.10%(n=6);method recovery rate was 95.4%-114.3%(RSD=9.0%,n=6);matrix effect was 63.5%-70.2%(RSD=10.39%,n=6). The t1/2 of cefdinir in rats in vivo was(0.54±0.01)h,MRT was(1.90± 0.14)h,cmax was(32.92±0.81)μg/mL,tmax was(1.50±0.02)h,AUC0-24 h was(46.65±0.44)μg·h/mL and AUC0-∞was(46.83± 0.44)μg·h/mL. CONCLUSIONS:The method is rapid,accurate and simple,and can be used for the determination of cefdinir con-centration in rat plasma and its pharmacokinetics research.

Compositional differences in different processing technology of radix paeoniae alba and different origin of red peony / 中国基层医药

Objective To determine and compare the contents of oxypaeoniflorin and paeoniflorin of Paeoniae Radix,and to improve the quality standard of Radix Paeonia.Methods The contents of oxypaeoniflorin and paeoniflorin in different kind of White and Red Peony Root were successfully analyzed by HPLC.Results The content of oxypaeoniflorin in Red Peony Root is more than White Peony Root at 0.8361％ ;The content of paeoniflorin in White Peony Root is more than Red Peony Root at 0.2157％.The proportion of paeoniflorin and oxypaeoniflorin in White Peony Root is more than Red Peony Root.Conclusion With HPLC technology,quantitative analysis of active constituents in Paeoniae Radix was performed accurately.