中药化学对照品木蝴蝶苷B的稳定性研究

Stability Study of Baicalein-7-O-diglucoside

目的对木蝴蝶苷B固体和在不同溶液中的稳定性进行研究。方法采用HPLC-DAD对不同温度下的木蝴蝶苷B固体和不同条件下的木蝴蝶苷B溶液进行色谱分离,经过归一化纯度分析对其稳定性进行比较和分析,明确木蝴蝶苷B的稳定性影响因素;然后采用HPLC-MS对木蝴蝶苷B在不同溶剂中主要降解产物进行分析。结果①木蝴蝶苷B固体在40、80和105℃下稳定、且对光稳定;②木蝴蝶B在水中较为稳定,在体积分数50%、70%甲醇、体积分数50%、70%乙醇溶液中不稳定。③木蝴蝶苷B在体积分数50%甲醇、体积分数50%乙醇和水溶液中降解产物分别为7-甲氧基黄芩素、7-乙氧基黄芩素和黄芩素。结论本次实验表明,木蝴蝶苷B对热和光稳定,但在溶液状态下不够稳定,尤其在体积分数50%甲醇溶液和体积分数50%乙醇溶液中易发生降解,建议木蝴蝶苷B对照品溶液选择采用水作为溶剂,或者临用现配,并在配制后立即放入冰箱冷藏保存。

OBJECTIVE To investigate the stability of baicalein-7-O-diglucoside.METHODS The chromatographic purity of baicalein-7-O-diglucoside and its solution in different condition was analyzed by HPLC-DAD.The degradation products of baicalein-7-O-diglucoside in its solvent were identified by LC-MS.Three degradation products in the solvent of baicalein-7-O-diglucoside were identified with applying electrospray ionization(ESI) source in the positive ion mode.RESULTS ① Baicalein-7-O-diglucoside was stable with light and in 40,80 and 105 ℃ within the inspection time in solid state.②Baicalein-7-O-diglucoside in water was stable in room temperature and degrades quickly in 50% methanol and 50% ethanol.③The degradation products of baicalein-7-O-diglucoside in solvent were 7-methoxy baicalein,7-ethoxy baicalein and baicalein.The above research provides that baicalein-7-O-diglucoside is stable in solid state.Baicalein-7-O-diglucoside degrades in 50% methanol and 50% ethanol.CONCLUSION Water should be used as the solvent for solution of baicalein-7-O-diglucoside.The solution of baicalein-7-O-diglucoside should be made up before use or stored in the refrigerator immediately after preparation.