基于传质模型探索乙醇溶液环境中黄连生物碱的纳滤分离机制

Exploring the Nanofiltration Mechanism of Coptidis Rhizoma Alkaloids in Ethanol Solution by Mass Transfer Model

目的:基于传质模型探索乙醇溶液环境中黄连生物碱的纳滤分离机制。方法:采用纳滤传质模型结合Box-Behnken设计方法,分析黄连生物碱树脂洗脱液的纳滤分离规律,探索乙醇溶液环境下3种生物碱类成分的纳滤分离机制。结果:根据构建的纳滤分离数学模型,用于考察分离因素与成分分离行为的内在关系,结果显示乙醇溶液浓度对盐酸小檗碱、盐酸巴马汀、盐酸黄连碱截留率均具有显著性影响,与溶质的油水分配系数存在相关性。拟合方程并分析黄连生物碱截留率对考察因素的敏感系数,结果显示3种生物碱对纳滤膜相对截留分子质量的敏感系数均大于50、溶液pH的敏感系数均大于30,孔径筛分、电荷效应占据纳滤分离的主导地位。黄连生物碱传质系数随着乙醇浓度升高而下降,对乙醇浓度的敏感系数表现为盐酸巴马汀>盐酸小檗碱>盐酸黄连碱。结论:根据3种生物碱传质系数与乙醇浓度的幂函数曲线差异,为中药复杂溶液体系下多成分的有序分离提供了理论支撑。

Objective:To explore the mechanism of nanofiltration separation of Coptidis Rhizoma alkaloids in ethanol solution based on mass transfer model.Methods:Using a nanofiltration mass transfer model combined with Box-Behnken design,the nanofiltration separation rule of resin eluents of Coptidis Rhizoma alkaloids was summarized to analyze the separation mechanism of three alkaloids in ethanol solution.Results:The experiment showed that the nanofiltration separation mathematical model was valid,which could be used to investigate the internal relationship between factors and component separation behavior.The ethanol concentration had significant effect on the rejection of berberine hydrahloride,palmatine hydrahloride and coptidine hydrahloride,which correlated with the oil-water partition coefficient of solutes.By fitting the power function equation and analyzing the sensitivity coefficients of solute rejection to the investigated factors,the sensitivity coefficients of the three alkaloids to the molecular weight cut-off of nanofiltration were all greater than 50,and the sensitivity coefficients of pH were all greater than 30.The molecular sieving and charge effect were dominant in nanofiltration separation.The mass transfer coefficient of Coptidis Rhizoma alkaloids decreased with the extension of ethanol concentration,and the sensitivity coefficient of Coptidis Rhizoma alkaloids to ethanol concentration was palmatine hydrahloride>berberine hydrahloride>coptidine hydrahloride.Conclusion:According to the difference of the power function curves between mass transfer coefficients and ethanol concentration,it provides the theoretical support for the orderly separation of multiple components in the complex solution system of Chinese medicine.