Rotary fluorescence array microfluidic chip for rapid detection of multiple pathogens in foods using dual-discs assisted recycling for signal amplification.

BACKGROUND

The ability to rapidly and on-site detect multiple pathogens in food is crucial for food safety monitoring. The microfluidic chip integrated with aptamer (Apt) probes stands as a powerful tool for this venture. However, the utility of these chips has been constrained by the need for cumbersome fluid control devices, such as syringe pumps and bulky optical detectors, so the development of highly integrated integrated chips has become one of the priorities of biosensor development in recent years.

RESULT

In this work, a novel rotary fluorescence array microfluidic chip has been engineered for the simultaneous and rapid detection of three pathogens. The chip has three different detection regions and a double-layer structure composed of PDMS and glass. The Apts and its complementary DNA strands were immobilized on the gold nanoparticle layer in the detection region for pathogen identification, the fluorescence (FL) from the double-stranded staining solution added after the reaction was used for signal amplification. Different arrays of gold discs can be employed to identify various bacteria. This method enables the detection of Staphylococcus aureus (S.A), Salmonella typhimurium (S.T), and Vibrio parahemolyticus (V.P) in food samples within 30 min at a sensitivity of 7-39 CFU/mL.

SIGNIFICANCE

The microfluidic chip has good specificity and sensitivity while avoiding cross interference, and the ratio form of quantification avoids background light interference. Different arrays can be used to identify different bacteria, which is of great significance for the rapid detection of a variety of foodborne pathogens in the field.