Rapid detection of ochratoxin A on membrane by dot immunogold filtration assay

BACKGROUNDOchratoxin A (OTA), a widely distributed mycotoxin produced by certain species of Aspergillus and Penicillium, has been identified as a carcinogenic, hepatotoxic, teratogenic, nephrotoxic and immunotoxic toxin. To reduce the risk of OTA contamination, a rapid, inexpensive, suitable and on-site assay for its detection is required. RESULTSIn this study a dot immunogold filtration assay (DIGFA) of OTA on high-flow nitrocellulose membrane was developed. Firstly colloidal gold was synthesized and colloidal gold-polyclonal antibody (PcAb) conjugates against OTA were prepared at the optimal colloidal gold-labeled pH value and package amount. Then the colloidal gold-PcAb conjugates were used to develop the OTA DIGFA. The results demonstrated a visual detection limit of approximately 10ng mL(-1) OTA. In addition, this method had no cross-reaction with zearalenone, aflatoxin B1 or citrinin. CONCLUSIONThese results indicated that the developed DIGFA could be applied for the actual detection of samples without complicated steps. (c) 2015 Society of Chemical Industry