尼索地平光解稳定性研究

STUDIES ON PHOTODEGRADATION STABILITY OF NISOLDIPINE

采用双波长分光光度系数倍率法测定尼索地平在不同浓度下在乙醇中的光解动力学参数。结果表明）当浓度低于３×１０－５ｍｏｌ·Ｌ－１时呈表观一级反应，速率常数为１．６２６×１０－２ｍｉｎ－１，而高于２×１０－４ｍｏｌ·Ｌ－１时则为零级反应，速率常数为１．２３８×１０－６ｍｏｌ·Ｌ－１·ｍｉｎ－１。此结果提示该药在生产、贮存及制剂学研究过程中，其浓度宜控制在２×１０－４ｍｏｌ·Ｌ－１以上。

The Parameters of photodegradation kinetics of nisoldipine at different concentrations in ethanol were measured by using dual wavelength Kratio ultraviolet spectrophotometry. The results showed that the photodegradation could be described by an apparent first-order reaction if the concentration was lower than 3 × 10-5 mol.L-1,and by a zero-order reaction if the concentration was higher than 2× 10-4 mol. L-1, and the rate constants are 1. 626×10-2 min-1 and 1. 238 ×10-6 mol.L-1 .min-1 respectively. The results also showed that the concentration of the drug should be adequately controlled over 2 × 10-4 mol.L-1 in manufacture.storage, and study.