目的研究湿度和温度对维生素C稳定性的影响。方法利用均匀设计分散原理,确定药物的湿度、温度平面,采用单测点法获得与药物有关的降解动力学参数。结果维生素C的降解遵从一级反应动力学方程;利用平面单测点法获得了药物有关的动力学参数:Ea=110.0%±1.6%kJ.mol-1、m=4.51%±0.21%和A=(6.29%±0.86%)×1012h-1。结论结果与经典恒温恒湿法基本一致,但平面单测点法节约样品且试验工作量减少。
OBJECTIVE To evaluate the influence of humidity and temperature on the stability of Vit C.METHODS The moisture and temperature plane of a drug were determined based on the dispersive principle of uniform design.Then,the kinetic parameters were obtained by the single time point experiment.The stability of Vit C,as a solid state model,was investigated.RESULTS It was found that the degradation of Vit C obeyed the first-order kinetics.The kinetic parameters obtained from the plane single time point experiment,Ea=110.0%±1.6% kJ·mol-1,m=4.51%±0.21%,A=(6.29%±0.86%)×1012 h-1,were comparable to those from isothermal studies at constant humidity.CONCLUSION In comparison to isothermal studies at constant humidity,the present proposed method saved time,labor,and materials.