Abstract:

A high-performance liquid chromatography （HPLC） method was established for the determination of 9 retinoids in cosmetics. The sample pretreatment and chromatographic conditions were optimized, and this method was used to assess quality and safety risks of 56 batches of cosmetics containing retinoids. The samples were dissolved in tetrahydrofuran （THF） and ultrasonically extracted with acetonitrile. The nine retinoids were separated on a C₁₈ chromatographic column, and eluted with a gradient of acetonitrile-aqueous ammonium acetate solution （5 mmol/L） -THF. The results show that the nine retinoids exhibit good linearity with the correlation coefficients exceeding 0.998. Five cosmetic matrices are selected for spiked recovery tests, yielding average recoveries ranging from 86.96% to 109.63%, with RSDs between 0.30% and 8.55%. The detection results of the 56 batches of samples show that retinoids in 29 batches of samples do not conform to their labels. Among them, eight batches that claim specific retinoid ingredients on their registration contain no detectable levels, indicating false efficacy claims. Additionally, three batches contain prohibited ingredients, specifically retinoic acid and isotretinoin, posing substantial safety risks. Therefore, regulatory authorities should continuously monitor the safety of retinoid ingredients and related cosmetics, urge enterprises to standardize production. Furthermore, comprehensive supervision of cosmetic labeling and efficacy claims remains imperative.

Key words: cosmetic, retinoid, high-performance liquid chromatography, product label, efficacy claims