ABSTRACT
Objective: To develop an HPLC method for the simultaneous determination of 3 ultraviolet absorbers (benzylidene camphor sulfonic acid, camphor benzalkonium methosulfate, 4-methylbenzylidene camphor) in cosmetics.Methods: After extracted by acetonitrile-methanol-ammonium acetate aqueous solution-tetrahydrofur(30∶35∶30∶5, v/v)(for lotion and milk) or acetonitrile-methanol-ammonium acetate aqueous solution(30∶20∶50, v/v)(for cream and powder), the UV absorbers were separated on a Thermo scientific C18 column (250 mm×4.6 mm,5 μm) at 35 ℃ with methanol, acetonitrile and 0.02 mol·L-1ammonium acetate aqueous solution (pH 5.15 adjusted by glacial acetic acid) as the mobile phase with gradient elution at the flow rate of 1.0 ml·min-1, and then analyzed by a DAD detector at the wavelength of 288 nm and 300 nm.Results: Benzylidene camphor sulfonic acid, camphor benzalkonium methosulfate and 4-methylbenzylidene camphor showed good linearity within the range of 12.26-98.06 μg·ml-1(r=0.999 9), 9.31-74.48 μg·ml-1(r=0.999 9) and 6.86-54.88 μg·ml-1(r=0.999 9), respectively.The limit of detection (LOD) and the limit of quantitation (LOQ) were 4.6, 6.4 and 1.6 ng and 17.4, 15.9 and 5.5 ng, respectively.The average recovery was 99.2%(RSD=1.58%), 99.8%(RSD=2.38%) and 99.2%(RSD=2.03%)(n=36), respectively.Conclusion: The method is simple, rapid, reproducible, accurate and reliable, and can be applied in the determination of ultraviolet absorbers in cosmetics.