Abstract: A reliable method for quatitive analysis of clenbuterol by liquid chromatograph couple of tandem mass spectrometry was estiblished. Multi-reactions monitoring (MRM) technology of triple-quadrupole tandem mass spectrometer, positive scan mode was employed. Transition ion pair of m/z277→259 was selected as MRM ions pair. The areas of MRM ion flow peaks were used to determine the quantity of clenbuterol. The standard curve for clenbuterol showed good linearity over the concentration range of 0.14￣60μg/L(γ=0.99985). The recoveries of clenbuterol at added standard to pork were above 90%, the limited of quantitative detection was 0.07μg/L, and the running time of each sample was 3 minutes. This method was highly sensitive, fast, and very accurate. Therefore, it is possible to be applied to study the residue of various medicine in animal tissues.

Key words: HPLC, MS/MS, MRM, clenbuterol