A sandwich ELISA for the detection of fish and fish products

Abstract

Fish is classified as one of the major allergenic foods. However, a reliable assay for detecting the presence of fish protein is not available. In this study, a sandwich enzyme-linked immunosorbent assay (sELISA) was developed using polyclonal antibodies raised against a 36 kDa thermal-stable fish muscle protein. The sELISA was able to detect both raw and cooked (100 °C, 8 min) fish samples of all 63 common species tested without any cross-reaction with non-fish samples. The assay can also detect fish products with different processing (salting, smoking and canning). The detection limit of the assay was 0.1 ppm for both raw and cooked fish (whiting, pollock and basa) in crab meat. The assay exhibited low intra- (CV ≤ 8.9%) and inter-assay variability (CV ≤ 9.3%). The rates of false-positive and false-negative were 0%. This fish-specific sELISA is, therefore, an effective assay for the detection of fish muscle protein in food for the protection of fish-allergic individuals.