OBJECTIVE To establish a solid phase extraction-high performance liquid chromatography tandem mass spectrometry(SPE-HPLC-MS/MS) method for the simultaneous determination of 8 illegal added drugs(i.e., fluconazole, ketoconazole, econazole nitrate, miconazole nitrate, naftifine hydrochloride, tazarotene, etretinate and viaminate) in anti-acne cosmetics with 3 different matrix types(water-based, lotion and cream).

METHODS Cosmetic samples were extracted by methanol solution containing 1% tetrahydrofuran, and purified by HLB prior to injection. The separation was performed on a ZORBAX-C₁₈ column with gradient elution using 0.1% formic acid aqueous solution and methanol solution containing 0.1% formic acid as the mobile phase. The ionization was carried out in positive ion mode using an electrospray ionization source, and the determination was performed in multiple reaction monitoring mode. The quantification was achieved by the matrix-matched calibration curve method.

RESULTS Eight compounds had good linear relationship in their respective concentration range, the correlation coefficient was ≥0.995, the detection limit was 0.015−0.16 mg·kg⁻¹, the quantitative limit was 0.045−0.48 mg·kg⁻¹, and the average recovery was 89.5%−103.1%, the RSD was <10%.

CONCLUSION The method is simple, accurate and sensitive, which can be used for the detection of 8 illegal added drugs in anti-acne cosmetics.