场放大进样-胶束毛细管电泳法测定化妆品中3种糖皮质激素

Determination of 3 Corticosteroids in Cosmetics by Field Amplified Sample Introduction-Micellar Capillary Electrophoresis

摘要: 采用场放大进样-胶束毛细管电泳法对化妆品中氢化可的松、泼尼松和乙酸氢化可的松3种糖皮质激素进行了分离测定。电泳介质为0.20 mmol·L-1硼砂缓冲溶液(pH 9.0),运行电压为-20 kV,进样电压-20 kV,进样时间45 s,进水压力3 kPa,进水时间20 s,检测波长250 nm。在优化试验条件下,氢化可的松、泼尼松和乙酸氢化可的松的检出限分别(3S/N)为0.015,0.017,0.017 mg·L-1。应用此方法分析了化妆品样品,测得回收率在93.8%~107%之间,测定值的相对标准偏差(n=5)均小于5.1%。

Abstract: Micellar capillary electrophoresis with field amplified sample introduction was applied to the separation and determination of 3 corticosteroids, including hydrocortisone, prednisone and hydrocortisone acetate, in cosmetics. The optimized conditions were shown as follows: ① electrophoretic medium: 0.20 mmol·L-1 borax buffer solution of pH 9.0; ② conveying voltage: -20 kV; ③ sample injection voltage: -20 kV; ④ time of sample injection: 45 s; ⑤ pressure of water-intake: 3 kPa; ⑥ time of water-intake: 20 s; ⑦ detection wavelength: 250 nm. Values of detection limits (3S/N) for hydrocortisone, prednisone and hydrocortisone acetate found were 0.015, 0.017, 0.017 mg·L-1 respectively. The proposed method was used in the analysis of cosmetics sample, giving values of recovery in the range of 93.8%-107% with RSD′s (n=5) less than 5.1%.