ABSTRACT
Objective To study the pharmacokinetic features of reactive sulfide in rats after oral administration of Cinnabaris. Methods An HPLC coupled with precolumn derivatization method was developed for the pharmacokinetic features study on reactive sulfide in rats after oral administration of Cinnabaris. Results Good linearity (r>0.99) was found for reactive sulfide in plasma in the concentration range of 0.25–15 μmol/L (r>0.99). The LOQ and LOD of the method were 0.1 μmol/L and 0.02 μmol/L, respectively. The intra- and inter-day precision was less than 4.4% and 3.5% respectively, and the accuracy was -9.9%–6.0%. The average recovery rate was 74.9%. 0.6 g/kg Cinnabaris was given the rats for gavage, and the time-course pharmacokinetics parameters were as follows:Cmax(1.33±0.13) μmol/L, tmax(150±34) min, t1/2(323±62) min, AUC0-∞ (5743±297) ng/mL?h. Conclusion A sensitive, robust and accurate precolumn derivatization-HPLC method for the determination of plasma reactive sulfide is developed and validated. The method is successfully applied in the pharmacokinetic features study on reactive sulfide in plasma of rats after administration of Cinnabaris.
ABSTRACT
Objective: To analyze the free and hydrolyzed amino acids in Sojae Semen Preparatum (SSP) and Glycine max (GM) by pre-column derivatization RP-HPLC. Methods: Free amino acids extracted in HCl (0.1 mol/L) by ultrasonic method and hydrolyzed amino acids extracted in HCl (6 mol/L) by hydrolysis method were both derivated by the agent phenylisothiocyanate so as to analyze them by gradient elution. Results: There were 16 kinds of amino acids in both SSP and GM. The 16 kinds of amino acids had good linearity in the range of 0.031-1.750 μmol/mL with the coefficients of correlation all over 0.9979. The average recoveries were 91.02%-102.04% and the RSD values were between 1.01% and 4.81%. Conclusion: The method is not only sensitive and accurate, but also has the high repeatability and stability, and the 16 kinds of amino acids could be separated in the case of the samples with more impurities. The common C18 column is widely used for the determination of many other samples riched in amino acids at lower cost.