经典恒温法预测托拉塞米注射液的有效期

Predicting expiration date of torasemide injection by classical constant-temperature experiment

目的预测托拉塞米在室温下的有效期。方法采用HPLC法测定主药含量,用经典恒温法预测其有效期。结果托拉塞米的降解反应属一级反应,在室温(25℃)条件下的分解速度常数K25℃=5.186 9×10-6,该注射液在25℃时的有效期t0.9=2.32年。结论自制的托拉塞米注射液的有效期暂定为2年。

Objective To investigate the stability of torasemide injection and predict its expiration date in room temperatue. Methods The contents of torasemide were determined by HPLC. The expiration date was predicted by classical constant-temperature experiment. Results The contents of torasemide degradation with time according to a first order reaction at room temperature （25 ℃ ）. The disintegration rate constant K was K25 ℃ ： 5. 186 9 × 10 6 h-1 and the expiration date of to- rasemide injection was t0.9=2.32 years. Conclusion The torasemide injection expiration date was tentatively scheduled for two years.