A microfluidic biosensor for multiplexed detection of bacterial pathogens

The detection of bacterial pathogens has far-reaching impacts in various applications including food safety, water quality monitoring and clinical diagnosis. Owing to this, ongoing efforts have focused on developing biodetectors that are portable, offer rapid measurements and high specificity. Here, we present a microfluidic biosensor capable of fast, multiplexed detection of bacterial pathogens. This device utilizes a microsensor array patterned with synthetic, antimicrobial peptides that have species-specific targeting and binding capabilities. The peptides utilized in this work target for two species of bacterium; Streptococcus mutans and Pseudomonas aeruginosa, which are major sources of disease and infection in humans. Samples are autonomously driven within the device via a hydrophilic poly(dimethylsiloxane) PDMS surface coating. An electrical impedance sensing scheme is utilized for cell detection where cell binding results in changes of the sensor's impedance. Using this device, S. mutans and P. aeruginosa cells could be simultaneously detected in a polymicrobial sample within 20 min, demonstrating its potential as a rapid, point-of-care diagnostic technology.