Determination of Free Lanolin Alcohol and Residual Pesticides in Lanolin

OBJECTIVE To determine the content of free lanolin alcohol and residual pesticides in lanolin by gas chromatography, and to evaluate the feasibility of the established method. METHODS Gel permeation chromatography(GPC) was used for pretreatment, and the contents of free lanolin alcohol and residual pesticides were determined by GC-FID and GC-MS, respectively. And the qualitative analysis was conducted based on the retention time and quantitative analysis was conducted by total peak area. RESULTS The recovery of GPC pretreatment system met the requirements. Under the two established methods, the determinand were well separated; the satisfactory linearity with good correlation coefficients >0.999 5 were obtained; and the average recoveries were in the range of 90.49%-102.78%(n=6). The content of free lanolin alcohol in 3 batches of lanolin was <2.84%, cis-permethrin and trans-permethrin were determined in lanolin and the other residual pesticides were not detected. CONCLUSION The GPC-GC/FID and GPC-GC/MS method established in the study have good specificity, high precision, accuracy and robustness, which can be used for the separation and determination of free lanolin alcohol and six organophosphorus and pyrethroid residual pesticides in lanolin. At the same time, this study can provide reference for the quality control of lanolin.