TGA测定克拉霉素热分解动力学参数

采用热重分析(TGA)测定克拉霉素的热解曲线,用Ozawa法分析热分解过程,用多元线性回归法确定热分解机制函数,建立热降解动力学方程并用等温试验进行了验证.结果 表明,克拉霉素的热分解活化能较高,较为稳定,其热分解机制与自催化简单反应(Cn型)接近,回归系数0.9998597.其热解动力学参数活化能E、反应级数n和指前因子A对数分别为148.1111、1.3750和10.5158,催化常数k对数值为1.4306.所得动力学参数对该药物的稳定性评价及生产中的质量监控提供了理论依据.

Determination of clarithromycin thermal decomposition kinetic parameters with thermogravimetry analysis

TG (thermogravimetry) -DTG (differential thermogravimetry) were applied to determine the thermal decomposition curves of clarithromycin. Ozawa method and multivariate linear regression method were used to determine the thermal decomposition function and equation, and iso-thermal test was used for validation. The process of the thermal decomposition of clarithromycin was close to type Cn (n-th order with autocatalysis) with regression coefficient 0.9998597. The activation energy (E) was 148.1111 kJ/mol, the order of reaction (n) was 1. 3750, the logarithm of preexponential factor (A) was 10.5158 and the autocatalytic constant (k) was 1. 4306. This study provided theoretical foundation for the thermal stability evaluation and quality monitoring of clarithromycin.