Objective: The pupose of this study was to establish a rapid detection method for six chemical constitutes illegally added into health foods for diet. Method: This method used on the ultra-performance liquid chromatography-tandem mass spectrum (UPLC-MS-MS) technology

in which an Acquity BEH-C18 column(2.1 mm×50 mm

1.7 μm) was used with the mobile phase of 0.1% formic acid and acetonitrile by gradient elution.The target compounds were analyzed through electrospray ionization

selective ion scan(SIR) and multiple-reaction monitoring(MRM) modes. The compounds illegally added into slimming health foods were qualitatively identified and quantitatively determined according to the quasi-molecular ion peaks and the MRM chromatography peaks by comparison with those of reference substances.This method was used for analysis of 25 batches of health foods for diet. Result: Sibutramine hydrochloride and phenolphthalein were found in 6 batches of slimming health foods. Conclusion: The method is of great specificity

and sensitivity and can be used to detect the chemical compositions into the slimming health foods.