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A triple enzyme amplified immunosensor for highly sensitive detection of Ractopamine (RAC) in foodstuff was developed based on quartz crystal microbalance(QCM). The high sensitivity was achieved by double enzyme signal amplification strategy. The novel quartz crystal microbalance(QCM) sandwich immuno sensor which combine the advantages of high selectivity of immunoassays and the high sensitivity of QCM has been developed for the determination of trace residues of food production. In this study, the 4-tert-Btutylcalix[6]arene which can absorb benzyl group on RAC is immobilized at the bottom of the 96 orifice plate and used as capture probe. Meanwhile, we consider using colloidal gold to enrich anti-antibody/HRP and using thrombin to close the redundant binding sites at the same time which can trigger fibrinogen and TMB produce a large amount of sedimentation that serve as signal probes. And the GNPs can improve the load density of dual enzyme to amplify the signal of QCM sensor synchronously. Under optimum condition, the difference of frequency(Δf)after the addition of analytes from QCM was proportional to the concentration. Due to its high sensitivity, acceptable stability and good selectivity, the immunosensor realized reliable quantification of RAC in real fodder samples which has the potential to become a successful on-site screening method in food safety.