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• Ab-oriented amorphous Zn-based nanocomposites are produced for nanolabels. • A powerful CAbD strategy is raised by innovatively integrating three elements. • A mLFIA mediated by CAbD strategy was constructed for monitoring of SEMI and AOZ. • The CAbD strategy can be a universal and scatheless mAb 1 orientation approach. • The CAbD strategy reduces mAb 1 consumption and enhances the sensitivity of mLFIA. The quantity and orientation of antibodies are key elements affecting the bioactivity of immunoprobes, which have important influences on the sensitivity and specificity of immuno-biosensors. In this work, a multiplex lateral flow immunoassay (mLFIA) mediated by a powerful cascaded antibody directionality (CAbD) strategy was constructed for the simultaneous monitoring of nitrofurazone and furazolidone metabolites in food samples. Here the CAbD strategy innovatively integrated three elements: antibody staining by Coomassie brilliant blue R-250, directional anchoring of second antibodies (Ab 2) by the amorphous ZnO-based nanocomposites (ZnO-CBB-Ab 2 , ZnO-NCMs), and orientation of detection antibodies (mAb 1) by the Ab 2. The ZnO-NCMs play a double role in antibody orientation and signaling to exhibit. Thanks to the difference in surface electrical properties of Fc and Fab segments in immunoglobulin G, the excessive R-250 stained Ab 2 was anchored in ZnO-NCMs to form a multi-detection signal tag with colorimetric signal brightness. Compared with immobilization strategies of directly directional anchor-hold or post-adsorption of mAb 1 , this strategy can reduce the mAb 1 consumption, better ensure the activity and utilization efficiency of mAb 1 , and shorten the construction time of the mLFIA system. As expected, the mLFIA is given satisfactory performances with a calculated sensitivity of 0.106 and 0.060 ng mL−1 for nitrofurazone and furazolidone metabolites, respectively. The developed multiplex immunosensor ultimately shows its application potential for point-of-care testing by performing well in fish and honey samples with accredited recoveries. It's worth emphasizing that the CAbD strategy can be a universal and scatheless antibody-directed approach, especially in multiplex immunoassays for ultrasensitive food safety monitoring. [ABSTRACT FROM AUTHOR]