A high electron mobility transistor biosensor-based GaN for facile and sensitive detection of Staphylococcus aureus

Staphylococcus aureus is a common foodborne pathogen known to cause infections and poisoning. Hence, there is a pressing need to establish a rapid and sensitive detection method to mitigate the risk of bacterial contamination. Gallium nitride-based high electron mobility transistors (GaN HEMTs), representing emerging semiconductor sensors, have garnered significant research attention due to their advantages in integration, miniaturization, and rapid sensitivity. In recent years, the device has demonstrated excellent performance in detecting gases, heavy metals, and biomarkers. This paper prepares a novel GaN HEMT sensor with aptamer modification that can be applied to the detection of Staphylococcus aureus , which has great potential for application in food safety detection. The linear detection range of the functionalized device is 10 2  CFU/mL–10 7  CFU/mL, and the detection limit was 19 CFU/mL. In terms of specificity, interfering bacteria such as E. coli produced only 9.6 %–16.7 % of the current signal generated by S. aureus . When tested with actual samples, the device showed consistent detection results compared to those in the buffer system (95.2 %–97.2 %). This work demonstrates performance that is comparable to or even superior to other methods in terms of detection limits and response speed. Additionally, the HEMT sensor stands out by eliminating the need for supplementary reference electrodes or complex systems. With its rapid detection time, user-friendly operation, and exceptional selectivity, this sensor shows great promise for practical applications, particularly in field testing scenarios.