Fitness for purpose – Ochratoxin A analytical developments

Abstract

Laboratory accreditation involving third party auditing, the use of validated methods and participation in laboratory proficiency testing are essential elements for laboratory quality assurance in relation to ochratoxin A (OTA) analysis. A number of methods, mainly based on liquid chromatography (LC) with fluorescence detection (FD), coupled with immunoaffinity column or solid phase extraction cleanup, have been collaboratively validated and adopted as official standards for OTA determination in a variety of foods, including cereals, coffee, wine and beer. Enzyme-linked immunosorbent assays (ELISA) kits are widely used as screening methods for the occurrence of OTA in food. Novel technologies using anti-OTA antibodies (electrochemical immunosensors, fluorescence polarisation, lateral flow devices, enzyme-based flow through membranes, and surface plasmon resonance biosensors) have been proposed for rapid analysis of OTA in food and beverages, and may be applied for in situ measurements. Validation of these immunochemical methods and commercial kits is required. Liquid chromatography-mass spectrometry represents an adequate alternative to LC-FD particularly in the area of multi-mycotoxin analysis. OTA specific molecularly imprinted polymers are currently considered for cleanup as a potential and cheaper alternative to immunoaffinity or solid-phase extraction sorbents.