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

BACKGROUND: Aflatoxin B1 (AFB1) is a toxic metaboliteproduced by Aspergillus species that contaminates a wide range ofagricultural products. OBJECTIVES: This study was designed todevelop a rapid and highly sensitive immunoassay method inmicroarray format for quantitative detection of AFB1 to evaluatethe potential of microarray platform for high-throughput screening,which can be beneficial in food and feed industry. METHODS:Following successful optimization, using an indirect competitiveimmunoassay in dot blot format, AFB1-bovine serum albumin(AFB1-BSA) conjugate was contact-printed onto 16 isolated subarrayson multi-pad nitrocellulose coated slides; subsequently usedin competitive binding assays. RESULTS: Using the aforementionedassay, AFB1 was determined from 15 pg/g to 3.04 ng/g workingrange with detection limit (LOD) of 1 pg/g. To evaluate assayperformance in real food matrices, the authors spiked wheatsamples with different concentration of AFB1. After extraction,working ranges of 0.11-4.15 ng/g with detection limit of 30pg/g wasdetermined. Good recoveries (94±9%) were obtained, demonstratingaccurate detection of AFB1 concentrations in wheat samples.Assay procedure completed in 3 hours. CONCLUSIONS: The resultsindicated that the proposed developed assay in microarray formatcould be used for rapid and sensitive detection of AFB1in wheatsamples.