Development of antibody-based microarray assay for quantitative detection of aflatoxin B1

Aflatoxin B1 (AFB1) is a toxic metabolite produced by Aspergillus species that contaminates a wide range of agricultural products. This study was designed to develop a rapid and highly sensitive immunoassay method in microarray format for quantitative detection of AFB1 to evaluate the potential of microarray platform for high-throughput screening, which can be beneficial in food and feed industry. Following successful optimization, using an indirect competitive immunoassay in dot blot format, AFB1-bovine serum albumin (AFB1-BSA) conjugate was contact-printed onto 16 isolated subarrays on multi-pad nitrocellulose coated slides; subsequently used in competitive binding assays. Using the aforementioned assay, AFB1 was determined from 15 pg/g to 3.04 ng/g working range with detection limit (LOD) of 1 pg/g. To evaluate assay performance in real food matrices, the authors spiked wheat samples with different concentration of AFB1. After extraction, working ranges of 0.11-4.15 ng/g with detection limit of 30pg/g was determined. Good recoveries (94±9%) were obtained, demonstrating accurate detection of AFB1 concentrations in wheat samples. Assay procedure completed in 3 hours. The results indicated that the proposed developed assay in microarray format could be used for rapid and sensitive detection of AFB1in wheat samples.