[Simultaneous determination of 33 hair dyes in oxidative hair dye products by high performance liquid chromatography].

A method was developed for the simultaneous determination of 33 hair dyes in oxidative hair dye products by high-performance liquid chromatography (HPLC). The analytes were separated on a Waters Atlantis T3 MV Kit column (250 mm×4.6 mm, 5 μm) by gradient elution using phosphate buffer-acetonitrile as mobile phases. The components were detected at two different wavelengths of 235 and 280 nm using a diode array detector. The results showed that the method had good linearity with correlation coefficients exceeding 0.999. Precision was good for the 33 analytes, with the relative standard deviations (RSDs) less than 2%. Stabilities of tetraaminopyrimidine sulfate and 2,4-diaminophenoxyethanol HCl in 12 h, as well as other analytes in 24 h, were good, with RSDs less than 5%. Recoveries of the method ranged from 77.6% to 116.3% at three different concentration levels. The method proved to be simple, rapid, and accurate, suitable for the determination of various hair dyes in oxidative hair dye products.