奥硝唑在水溶液中的降解动力学研究

Study on Degradation Kinetics of Ornidazole in Aqueous Solution

目的:研究奥硝唑在水溶液中的降解动力学,为其制剂开发提供参考。方法:通过经典恒温试验,应用HPLC法测定奥硝唑在不同pH值、不同温度、不同浓度、不同缓冲液条件下的降解动力学参数。结果与结论:奥硝唑在水溶液中的降解呈现一级动力学特征,其降解速率与溶液pH值、温度、缓冲盐种类及浓度有关。最稳pH值为3.6。随着温度、缓冲盐溶液浓度的增加,奥硝唑的降解增快。缓冲盐溶液浓度较低时。奥硝唑在枸橼酸盐缓冲液中较磷酸盐缓冲液、醋酸盐缓冲液中稳定;缓冲盐溶液浓度较高时,奥硝唑在醋酸盐缓冲液中较磷酸盐缓冲液、枸橼酸盐缓冲液中稳定。

Objective： To study the degradation kinetics of ornidazole in aqueous solutions. Methods： The HPLC method and constant temperature mode were used to determine the degradation kinetic parameters of ornidazole at different pH, temperatures, concentrations and species of buffers. Results and Conclusions： Degradation of ornidazole in aqueous solution followed first-order kinetics, and the prim for ornidazole was 3.6. The degradation rate increased with temperature and buffer concentration. The species of buffer solutions seem to have different impacts on the catalytic process. At low buffer concentrations, ornidazole was more stable in a citrate buffer solution, while at high buffer concentrations, ornidazole was more stable in an acetate buffer solution.