高效液相色谱法检测除螨祛痘类化妆品中甲硝唑和替硝唑

Determination of Metronidazole and Tinidazole in Anti-Acne Cosmetics by HPLC

目的建立同时测定除螨祛痘类化妆品中甲硝唑和替硝唑的高效液相色谱(HPLC)法。方法采用Diamonsil(钻石)C18柱(250mm×4.6mm,5μm),以0.05mol/L磷酸二氢钾溶液(用磷酸调pH至3.5)-甲醇(80∶20)为流动相,检测波长为310nm。结果甲硝唑和替硝唑质量浓度分别在2.205～205.24μg/mL和2.002～200.2μg/mL范围内与峰面积线性关系良好,r=1.0000(n=8),甲硝唑和替硝唑的平均回收率分别为98.80%和98.45%,RSD分别为2.20%和2.46%(n=6)。结论所建立的HPLC法简便易行、准确、重现性好,可同时用于祛痘类化妆品中甲硝唑和替硝唑两种禁用物质的检测。

Objective To establish a HPLC method for the determination of metronidazole and tinidazole in anti-acne cosmetics. Methods The sample was analyzed on Diamonsil C18 column. The mobile phase was 0.05 mol/L potassium dihydrogen phosphate solution （adjusting to pH 3.5 by phosphoric acid） -methanol（80 ： 20）. The wavelength was at 310 nm. Results The correlation coefficients of linear calibration curves were 1. 000 0 within the metronidazole concentration range of 2. 205-205.24 μg/mL and tinidazole concentration range of 2. 002-200. 2 μg/mL. The average reco, ery rates of metronidazole and tinidazole were 98.80% and 98.45% respectively. Conclusion The method is simple, accurate and reproducible. It can be used for the determination of metronidazole and tinidazole in anti- acne cosmetics.