Tetracycline antibiotics are intensively used in veterinary medicine and as food additives for growth promotion in the farming industry, and they can product negative effect for human body.It is very important to determine the accurate concentration of trace tetracyclines in foodstuff samples.Because foodstuff samples have very complex matrices, a routine solid-phase extraction(SPE) is always required.However, SPE is usually based on nonselective interactions between the analyte molecule and the sorbent, which often leads to coextraction of many matrix components.