[Determination of six ultraviolet filters in cosmetics by high performance liquid chromatography coupled with...

A method for the simultaneous determination of six UV filters in cosmetics by high performance liquid chromatography (HPLC) coupled with solid-phase extraction (SPE) based on graphene sponge (GS) was established. The samples were extracted with methanol by ultrasonic, then cleaned up by home-made SPE cartridges and eluted with acetone. The six UV filters were separated on an Agilent Zorbax SB-C18 column (150 mm×4.6 mm, 5 μm). Methanol-water (95:5, v/v) was used as mobile phase and the detection wavelength was 340 nm. The results showed that the limits of detection (LODs, S/N=3) and the limits of quantification (LOQs, S/N=10) of the six UV filters were 0.08-1.82 μg/L and 0.26-6.07 μg/L, respectively. The correlation coefficients (r) were greater than 0.999 except 2-(2'-hydroxy-5'-methyl-phenyl) benzotriazole (r>0.997). The recoveries of the six UV filters were 61.1%-119.0%, and the relative standard deviations (RSDs) were less than 1% (n=6) at the three spiked levels of 20, 50 and 100 μg/L. The method is simple, rapid, sensitive and repeatable, and is suitable for the determination of the UV filters in cosmetics.