| In this paper, an accurate analysis method for seven kinds of sexual hormones in cosmetics, namely, estriol, diethylstilbestrol, estradiol-17β, estrone, testosterone, methyl-testosterone and progesterone was investigated systematically in order to improve the traditional techniques. This method was achieved easily and suitable for skeleton laboratory. The pretreatment procedure of cosmetics samples was also discussed, and the accurate HPLC-DAD method that simultaneously determinated estriol, diethylstilbestrol, estradiol-17β, estrone, testosterone, methyl-testosterone and progesterone was set up which provides available basic conditions for the foundation of national determination method of sexual hormones in cosmetics.During the pretreatment procedure, the extraction of seven kinds of sexual hormones in cosmetics was carried out by liquid-liquid extraction. Samples were saponified with 15 g.L-1 sodium hydroxide firstly, and then by the choice of different extractors and their pH and volume the optimum pretreatment conditions—the sexual hormones were extracted with 30 mL dichloromethane under acidic conditions (pH=4, adjusted with 1 mol.L-1 HCl) were obtained. The method of reduced pressure revolving evaporation was confirmed as the concentrating and purifying method through the analysis of different concentrating principle. In the linear ranges of determination from 5 mg.L-1 to 100 mg.L-1, the average recoveries for seven sexual hormones obtained by this pretreatment procedure ranged from 88.4% to 98.6% with the relative standard deviations (RSD) of 0.5% to 2.8%, which was pretty satisfied.The conditions of HPLC-DAD were developed for simultaneous determination of seven kinds of sexual hormones in cosmetics. By the research of the factors of different components of mobile phase, flow rate and different detection wavelength that influenced seven sexual hormones, chromatographic conditions were optimized and confirmed, that were: column, Eclipse XDB-C18 (4.6 mm×250 mm, 5μm); mobile phase, V(methanol):V(water):V(acetonitrile) = 34:30:36; detection wavelength, 230 nm; flow rate, 1.0 mL.min-1 ; volume of injecting sample, 10μL, which made seven kinds of sexual hormones well separated. The repeated RSDs of retention time of seven kinds of sexual hormones in six days were 0.06 %～0.3% which has shown that the stability of HPLC instrument was fine. The repeated RSDs of peak areas for a certain concentration of mixed standard seven sexual hormones were 0.2%～0.7%, and the limits of detection of seven sexual hormones were 0.2 ng to 2.3 ng.(SNR is 3). It has shown that the precision of this method was high.The established pretreatment and analysis method were applied successfully to 113 different forms of cosmetics, such as cosmetics made of liquid, half-liquid and solid, and the rate of determination of seven sexual hormones was 7.96%. Through the qualitative and quantitative analysis of the samples, the pretreatment and analysis method established in this paper is in point in the determination of seven sexual hormones in various kinds of cosmetics and also has highly reliability.According to the results of determination of seven sexual hormones in cosmetics, there are different kinds of sexual hormones in some cosmetics presently. Although the contents of sexual hormones are not high, they are harmful to people. Therefore, it is very important and signifying that the research of sexual hormones in cosmetics should be strengthened in order to establish the national criterion about it. It is not only the required situation of our country but also one of the preconditions of healthy development of cosmetics industry.
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