高效液相色谱柱后衍生法测定化妆品中的甲萘威

Determination of carbaryl in cosmetics by high performance liquid chromatography with postcolumn derivatization

目的建立测定化妆品中甲萘威的高效液相色谱-柱后衍生测定法。方法水剂、乳状和膏霜状化妆品用甲醇提取后,于5 000 r/min离心,上清液用0.22μm微孔滤膜过滤后,经Carbama Analysis C_8(5μm,4.6 mm×250 mm)色谱柱分离,以水/甲醇=45/55(V/V)为流动相,流速为1.0 ml/min,柱温为37℃,进行分离后,目标物进柱后衍生系统生成高荧光强度的化合物,然后用荧光检测器进行测定,激发波长为330 nm,发射波长为465 nm。结果甲萘威在0.01 mg/L^1.0 mg/L时具有良好的线性,相关系数为0.999 9,方法检出限为0.03 mg/kg,定量限为0.1 mg/kg;在低、中、高3种浓度(0.2 mg/kg、1.0 mg/kg、5.0 mg/kg)添加水平下,回收率为94.9%~103.7%,相对标准偏差为1.16%~5.25%。结论该方法前处理简单,检测灵敏度高,准确度好,适用于水剂、乳状和膏霜状化妆品中甲萘威的测定。

Objective To develop a method for the determination of carbaryl residue in cosmetics by high performance liquid chromatography（ HPLC） method with postcolumn derivatization. Methods Lotion,emulsion and cream cosmetics were extracted by methanol,and the extract was centrifuged at 5 000 rpm,then the clear upper phase was filtered through a 0. 22 μm membrane. The HPLC separation was carried out on a Carbama Analysis C8 column（ 5 μm,4. 6 mm × 250 mm） and water-methanol（ 45∶55,V/V） was used as mobile phase in isocratic mode at a constant flow rate of 1. 0 ml/min. Moreover,the column temperature was maintained at 37 ℃. After postcolumn derivatization,the carbaryl residue was determined by HPLC-fluorescence detection. The fluorescence was monitored with excitation at 330 nm and emission at 465 nm. Results The standard calibration curves were linear for carbaryl residue in different matrixes in the concentration range of 0. 01 mg/L-1. 0 mg/L,and the correlation coefficient was 0. 999 9. The limit of detection was 0. 03 mg/kg and the limit of quantification was 0. 1 mg/kg.The mean recoveries at three spiked levels（ 0. 2 mg/kg,1. 0 mg/kg,5. 0 mg/kg） were within 94. 9%-103. 7% and the relative standard deviations（ RSDs） were within 1. 16%-5. 25%. Conclusion The method is simple and accurate with good recovery rate,which is suitable for the analysis of carbaryl residue in different cosmetic samples,including lotions,emulsions and creams.