Sensitive and automated detection of bacteria by CRISPR/Cas12a-assisted amplification with digital microfluidics

Abstract

The development of new diagnostic platforms for sensitive and rapid detection of bacterial pathogens is of great significance for improving precision medication for infectious disease and food safety control. Currently, many bacterial detection methods are limited by low detection sensitivity, sophisticated protocols, long processing times and labor-intensive procedures. Here, we report a DMF-Cas12a method for rapid, sensitive and automated analysis of bacterial pathogens by integrating the CRISPR/Cas12a system with a digital microfluidic chip (DMF). In the assay, Staphylococcus aureus could be detected with high sensitivity and specificity, and the detection limit of the assay was found to be 32 CFU/mL. With the tiny volume and automation capabilities of DMF, this assay was accomplished in 55 min and consumed only 6.6 μL reagent. This platform was successfully applied to urine and milk samples with excellent sensitivity and reliability. The DMF-Cas12a method shows good potential in automated and highly sensitive pathogen detection for a wide variety of biological applications.