Development of a direct and visual isothermal method for meat adulteration detection in low resource settings

Simple, fast and efficient method for on-site detection of meat adulteration is of increasing demand in low-resource regions. Here, a direct and visual denaturation bubble-mediated strand exchange amplification method (SEA) was developed to detect meat adulteration by targeting the mitochondrial sequence from duck, which required only a heating block. The method allowed detecting as low as 10 pg/μL duck DNA and 0.1% duck meat in binary mixtures, sufficiently meeting the demand of meat adulteration detection. Notably, the method realized instrument-free readout by significant color discrimination of positive and negative results. By coupling with fast DNA release, a direct SEA method was developed and reduced the whole detection time to 1 h, eliminating complex DNA extraction process. The developed method provided a promising strategy with integration of fast sample lysis, miniaturized reaction platform and visual readout for meat adulteration, especially suitable for low resource point-of-care settings.