Rational incorporating of loop-mediated isothermal amplification with fluorescence anisotropy for rapid, sensitive and on-site identification of pork adulteration

Abstract

Meat and meat products are one of the valuable foods that provide a variety of essential nutrients for human beings, and their authentication is of great significance for guaranteeing food quality and safety and also the human health. In this research, we present a proof-of-concept strategy of loop-mediated isothermal amplification (LAMP) coupled fluorescence-anisotropy (FP) for rapid, sensitive and accurate judgement of adulteration. Relationship between LAMP and FP is easily constructed by using FITC-labeled primer, which shows limited FP signal at its free state because of fast rotation. With pork DNA, the short primer can be efficiently amplified into macromolecules by LAMP, undergoing significant increase of molecular weight restricting the rotation of FITC. This change leads to a dramatic enhancement of FP signal for adulteration screening. Results show that LAMP-FP well integrates the high efficiency of LAMP with the simplicity of FP, achieving detection limit of 0.01% (wt. %). The performance of LAMP-FP strategy is comparable to those of qPCR. Importantly, this unique method is also available for the commercial processed products. We expect this LAMP-FP will provide a new direction to build versatile analytical tools in food safety monitoring.