Abstract:

A method for the simultaneous determination of 9 components （adapalin, tretinoin, isotretinoin, viaminate, tazarotene, retinol, retinyl acetate, retinyl propionate, retinol palmitate） in cosmetics by high performance liquid chromatography was established. The effects of extraction solvents on the retinol components were explored, and it is found that when the extraction solvent is methanol-isopropanolas （volume ratio 55∶45）, the recovery rate of various retinol components can reach the best level. Meanwhile, to obtain higher sensitivity, the acidic mobile phase methanol-isopropanolassystem was used to separate the retinol components. It is found that when the pH is 4.5 and the concentration is 5 mmol/L, the resolution of the 9 retinol components can achieve the best results. Finally, the 9 retinol components were separated by CAPCELL PAK C₁₈ （4.6 mm×250 mm×5 μm） column using 5 mmol/L ammonium acetate （pH=4.5）-methanol-isopropanolas as the mobile phase, and qualitative and quantitative analysis was performed by high performance liquid chromatography with DAD detection under the detection wavelength of 238, 325 and 355 nm. The flow rate was 1.0 mL/min. The results show that there is a good linear relationship in the range of 0.12-29.19 mg/L between concentration and peak area with R² greater than 0.995 9. The limits of detection for adapalin, tretinoin, isotretinoin, viaminate, iazarotene, retinol, retinyl acetate, retinyl propionate, and retinol palmitate are 2.01, 0.95, 1.72, 1.65, 0.78, 1.23, 1.94, 5.29 and 0.22 μg/g, respectively, and the limits of quantification are 6.70, 3.17, 5.73, 5.50, 2.60, 4.10, 6.47, 17.63 and 0.73 μg/g, respectively. The average recoveries are from 80.56% to 112.63%, with relative standard deviations in the range of 0.18% to 5.85%. This method has advantages such as simple pretreatment, high sensitivity, rapid and accurate. It is suitable for the simultaneous determination.

Key words: cosmetic, retinol, high performance liquid chromatography