Barcode-enabled detection of multiple meat adulterants by single-fluorescence-channel digital PCR on a self-digitalization biochip

Adulteration of high-value meats with cheaper alternatives poses significant health and economic risks. Therefore, the integrity of commercial meat products is of critical concern for both consumers and food safety authorities. To address this challenge, we have developed a barcode-enabled single-fluorescence-channel method leveraging the multiplex digital polymerase chain reaction for detecting potential meat adulterants. Our device employs a self-digitizing polydimethylsiloxane microfluidic biochip, which enables the automated loading of polymerase chain reaction reagents into thousands of microchambers without external pumps. By utilizing pre-designed barcodes as specific identifiers, we can distinguish DNA templates extracted from various animal species with only a single fluorescence channel. As a demonstration, this method is used to detect four types of meat (beef, chicken, pork, and duck) with a detection limit of up to 3 copies/μL, meeting the requirements for meat adulteration detection applications. This approach holds great potential for field testing of food adulteration or point-of-care applications when used in conjunction with portable single-channel fluorescence microscopes.