动态pH联接-扫集毛细管电泳法测定化妆品中迷迭香酸的含量

采用动态pH联接-扫集毛细管电泳法对化妆品中的迷迭香酸进行检测。用重力进样的方式,进样高度为15 cm的情况下,研究了硼砂浓度、pH、十二烷基硫酸钠(SDS)浓度、甲醇浓度、样品基体、进样时间、分离电压对富集与分离的影响。优化后的实验条件:15 mmol/L硼砂-45 mmol/L SDS(pH8.8)-15%甲醇为缓冲液,进样时间60s,分离电压16kV,样品中磷酸盐浓度10 mmol/L,样品基质pH 4.7。在上述条件下,迷迭香酸(RA)的线性回归方程式为y=539200ρ+53588(r=0.9985),线性范围为0.144～3.6μg/mL,检出限0.036μg/mL,迷迭香酸的回收率为92.5%～103%,相对标准偏差为2.5%。

Simultaneous determination of rosmarinic acid in cosmetics by dynamic pH junction-sweeping in capillary electrophoresis

A method of dynamic pH junction-sweeping in capillary electrophoresis was achieved for the analysis of rosmarinic acid in cosmetics.In the case of the sample height is 15 cm by gravity sampling,the effects of some conditions such as the concentration of borax,pH value,the concentration of SDS,the concentration of methyl alcohol,sample matrix,sample injection time,separation voltage were optimized.The optimized laboratory conditions: the buffer:15 mmol/L borax-45 mmol/L SDS(pH 8.8)-15% methyl,the sample injection time was 60s,the applied voltage was 16 kV,the concentration of phosphate in the sample was 10 mmol/L.The pH of the sample’s stromais 4.7.The linear equation of RA was y=539200x+53588,the correlation coefficient was 0.9985.The linear range was 0.144~3.6 μg/mL,and the limit of determination was 0.036 μg/mL.The recoveries found were in the range from 92.5% to 103%,with RSD of 2.5%.