Ultrasensitive indirect competitive ELISA and strip sensor for detection of furazolidone metabolite in animal tissues

Abstract

Nitrofurans are a class of drugs, which are typically used as antibiotics or antimicrobials illegally in aquiculture. In this paper, indirect competitive enzyme-linked immunosorbent assay and strip sensor were developed for detection of furazolidone metabolite, 3-amino-2-oxazolidinone (AOZ). These two methods could detect AOZ with high sensitivity and specificity. The immunosorbent assay with the half-inhibitory concentration of 0.074 ng/mL has a good recovery from 79.9% to 119.8% for detection of AOZ in pork, chicken, fish, shrimp, pork liver and chicken liver. Based on the developed strip sensor, the detection limit was 0.05 ng/g by the naked eyes and the cut-off value was 0.3 ng/g. The cross-reactivity with other nitrofurans, metabolites and some other compounds was all less than 0.1%. The sample recoveries ranged from 97.3% to 115.5%. Both these methods could be used for on-site detection of furazolidone metabolite at trace level in animal tissues.