Development of a PCR-based lateral flow immunoassay for the identification of rainbow trout ingredient in foods

A simple PCR-based lateral flow immunoassay (LFIA) was developed in this study to identify rainbow trout ingredient in foods. This assay was developed by coupling PCR amplification of rainbow trout DNA with the detection of labeled amplicon using LFIA. The rainbow trout-specific PCR primers targeted at mitochondrial ATP6 gene were successfully designed. The color signals of LFIA could be observed by the naked eye within 5 min. The reliability of this assay was confirmed by quantitative real-time PCR (qPCR). The proposed assay could achieve an LOD at 0.1 ng/& mu;L of rainbow trout DNA. The specificity of the primers was validated against 17 other species related to fish meat fraud and no cross-reactivity was identified, followed by successful test of commercial products for fish meat authentication. PCR-LFIA is simpler and faster than the conventional qPCR and has great potential to be applied to rapidly authenticate rainbow trout ingredient in foods.