Rapid and Sensitive Detection of 3-Amino-2-oxazolidinone Using a Quantum Dot-Based Immunochromatographic Fluorescent Biosensor.

To monitor the levels of furazolidone in edible animal tissues, a fluorescent sensor was developed for the determination of 3-amino-2-oxazolidinone (AOZ), the metabolite of furazolidone, featuring an immunochromatographic test strip assay (ITSA) integrated with a quantum dot (QD) label. The optimal QD-based ITSA sensor exhibits good dynamic linear detection for AOZ over the range of 0.1-100 μg/L, with a 50% inhibitory concentration (IC50) of 1.06 μg/L. The decision limit and the detection capability were 0.14-0.15 and 0.27-0.33 μg/kg, respectively, for this analyte using the QD-based ITSA sensor. These values represent an improvement over a previously reported gold nanoparticle-based immunochromatographic assay. The recoveries of AOZ in kinds of animal tissues were between 76.3 and 98.4% at the levels of 1.0, 5.0, and 10.0 μg/kg. The performance and practicality of our QD-based fluorescent immunosensor were confirmed by commercial ELISA kit and LC-MS/MS. In conclusion, the proposed sensor was a feasible detection method for AOZ analysis on site.