HPLC Determination of Salicylic Acid Ester UV Absorbers in Sunscreen Cosmetics

HPLC was applied to the simultaneous determination of 8 kinds of salicylic acid ester UV absorbers, including ethylhexyl salicylate, homosalate, octyl salicylate, phenyl salicylate, salicylic acid, salicylic acid hexyl ester with sixteen salicylic acid, ethylene glycol and benzyl salicylate, in sunscreen cosmetics. 1.000 0 g of sample was extracted by ultrasonic with 5 mL of ethyl acetate at 20℃ for 10 min, and the extract was separated on an Agilent ZORBAX Eclipse XDB-C₁₈ chromatographic column with a mixture of methanol, tetrahydrofuran, and 0.1% (w) formic acid solution as mobile phase for gradient elution. UV detection was made at the wavelength of 340 nm. Linear relationships were found between peak areas and mass concentrations of the 8 kinds of salicylic acid ester UV absorbers in the range of 5.0-100.0 mg·L^-1, with detection limits (3S/N) in the range of 0.5-2.5 mg·kg^-1. Recovery rates obtained by standard addition method were in the range of 90.6%-98.8%, and RSDs (n=6) were in the range of 1.4%-3.6%.