LC-MS/MS Determination of 22 Hormones in Cosmetics

LC-MS/MS was applied to the determination of residual amounts of 22 hormones in cosmetics. The sample was ultrasonically extracted with acetonitrile, and purified by Oasis HLB solid-phase extraction column (method 1) and gel permeation chromatography (method 2) separately. The hormones in the purified solution were separated on ZORBAX Eclipse XDB-C18 (100 mm×2.1 mm, 1.8 μm) column and eluted by gradient elution. Mixtures of acetonitrile and 0.1% (φ) formic acid solution with different mixing ratio by volume were used as eluants in the elution, and ESI+ mode was used in MS determination for 15 of the 22 hormones, and mixtures of acetonitrile and H2O with different mixing ratio by volume were used as eluants in the elution and ESI- mode was used in MS determination for the remainder 7 hormones. Multi-reaction monitoring mode was adopted in both the above cases. Values of detection limit (3S/N) found for method 1 were in the range of 0.01-0.40 mg·kg-1, while for method 2, were in the range of 0.1-4.0 mg·kg-1. Values of recovery found for method 1 were in the range of 61.5%-111%, while for method 2 were in the range of 60.8%-113%.