Integrated Dual-Modality Biosensor for Antimicrobial Susceptibility Testing and Antibiotic Prescription Guidance

Antimicrobial resistance (AMR) is a major threat to human health worldwide. The rapid detection of AMR and antibiotic susceptibility facilitates diagnostic and therapeutic processes. Over the past few years, several novel methodologies, including the use of fluorescence and colorimetric sensors, have been developed as promising strategies for rapid antimicrobial susceptibility testing (AST). However, these methods may result in false signals owing to uncontrollable factors. Therefore, fusing dual-mode features is necessary to improve diagnostic accuracy. This study developed a precise AST method by coupling catalase-expressing pathogens with a dual-modality integrated fluorescence/colorimetric biosensor. A bovine serum albumin-modified gold nanoclusters (BSA-AuNCs) bifunctional integrated sensor was explored for AST based on the bacterial catalase activity after exposure to antibiotics, which resulted in a different response to H₂O₂. Using this integrated dual-modality biosensor platform, the study successfully determined the antibiotic susceptibilities of Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus with values of area under the curve (AUC) from 0.9881 to 1. The dual-signal readout mode improves the accuracy and reliability of AST, which can be used to guide antibiotic prescriptions in clinical decision-making.