Abstract:Objective To establish a high-performance liquid chromatography (HPLC) assay for simultaneous detection of 5 preservatives including hydroquinone, phenol, catechol, benzoic acid, and sorbic acid in cosmetics. Methods The whitening cosmetics were extracted ultrasonically with methanol solvent, separated on C18 chromatographic column, and eluted with 5 mmol/L ammonium acetate-1‰ formic acid/methanol solution (30/70) at the flow rate of 1 mL/min. The column temperature was 35 ℃, and injection volume was 10 μL. Results There were good linear relationships among hydroquinone, phenol, catechol, benzoic acid, and sorbic acid (r>0.992). The average recovery rates were 97.82%-111.11%, and relative standard deviations were 0.23%-1.64%. Twenty-four batches of whitening cosmetics were detected by this method. Phenol, catechol, benzoic acid, and sorbic acid were effectively determined, but hydroquinone was not. Conclusion This method is simple, sensitive, and reproducible, and can be used for simultaneous detection of 5 preservatives such as hydroquinone in whitening cosmetics.