A portable microfluidic device integrating enzymatic and colorimetric assay for on-site detecting frozen-thawed meat

Much attention has been paid to the phenomenon that high-valued fresh meat is often adulterated with low-priced defrosted meat. A fast, low-cost and on-line method is required to discriminate thawed meat from fresh meat. In this study, a novel and facile β-hydroxyacyl-CoA dehydrogenase (HADH)-based colorimetric assay was integrated in a portable microfluidic cloth-based analytical device (μCAD). HADH-based enzymatic assay showed a good adaptability to various thawed meats without abundant interferences, and was visualized with thiazolyl blue and phenazine methosulfate as chromogenic reagent and cycling signal amplification mediator, respectively. A homebuilt HADH-based μCAD was successfully fabricated for the discrimination of fresh and thawed meat with a few drops of readily accessible meat exudate diluent. The complete inspection process can be completed within 5 min, which realizes the point-of-care testing discrimination in a more convenient way. The developed method and device have a great potential for fast and on-site detecting thawed meat and preventing meat adulteration.