Simultaneous Determination of 125 Prohibited Drugs in Anti-acne Cosmetics by LC-MS/MS

OBJECTIVE  To establish an LC-MS/MS method for simultaneous determination of 125 prohibited drugs(62 hormones, 51 anti infectives, 8 retinoids and 4 others) in anti-acne cosmetics.

METHODS  The sample was dispersed with 80% methanol solution for ultrasonic extraction. The separation and analysis were performed on an XBridge UPLC^® BEH C₁₈ column. The mobile phase consisted of methanol-5 mmol·L⁻¹ ammonium acetate aqueous solution(within 0.05% formic acid) by gradient elution. Electrospray ionization source was applied and operated in the positive mode and negative mode(ESI⁺/ESI⁻). Schedule multiple reaction monitoring(sMRM) mode was used to monitor ions. Matrix-matched calibrations were used to quantitative calculation.

RESULTS  The 125 prohibited drugs showed good linear relationship in their respective mass concentration ranges, and the correlation coefficients were all > 0.995. At four different concentration levels, the average recoveries were 73%–133%, and the relative standard deviation(RSD)(n=6) were not more than 12%.

CONCLUSION  This method has the characteristics of simple pretreatment, high sensitivity, strong specificity, one-time qualitative and quantitative analysis, and short analysis time. It is suitable for the determination of 125 prohibited drugs in anti-acne cosmetics.