HPLC Determination of 9 Ultraviolet Absorbents in Cosmetics

HPLC was applied to the determination of 9 ultraviolet absorbents,i.e.oxybenzone,3-benzylidene-camphor,3-(4′-Methylbenzylidene)-d-l camphor,octocrylene,padimate O,butyl methoxy-dibenzoylmethane,ethylhexyl methoxycinnamate,salicylic acid-2-ethyl-1-hexyl ester and homosalate in cosmetics.The sample was extracted with methanol,then separated on Ultimate XB-C18 chromatographic column with mixtures of methanol and water with different mixing ratios as mobile phase in the gradient elution,and determined with photodiode array detector.Linear relationships between values of peak area and mass concentration of the 9 ultraviolet absorbents were kept in definite ranges.Detection limits (10S/N) found were ranged from 12.5 to 100 mg·kg-1.On the base of blank sample,test for recovery was made by standard addition method;values of recovery found were in the range of 87.9%-95.7%,with RSD′s (n=6) in the range of 3.4%-4.5%.