Rapid and sensitive antimicrobial susceptibility testing of biofilm-forming bacteria using scalable paper-based organic transistors.

A scalable, cost-effective paper-based organic field-effect transistor platform has been developed for rapid antimicrobial susceptibility testing (AST) of biofilm-forming pathogens. Traditional AST methods are costly, labor-intensive, and slow, with a lack of standardized biofilm models. This system directly tracks protons generated by biofilms, which serve as key indicators of bacterial metabolism under antibiotic exposure. A proton-sensitive PEDOT:PSS channel is employed, where metabolic proton activity de-dopes the transistor, reducing conductivity. The engineered paper substrate facilitates rapid, high-quality biofilm formation, improving assay reliability. The platform was validated on three clinically significant pathogens against frontline antibiotics, providing real-time, quantitative antibiotic efficacy profiles. Integrated with a microcontroller and machine learning algorithm, results are displayed on a liquid crystal display (LCD), classifying antibiotic concentration relative to the minimum inhibitory concentration with over 85% accuracy. This clinically translatable system offers a high-throughput, point-of-care solution for efficient infection management and antibiotic stewardship.