Microfluidics for antimicrobial susceptibility testing: Current advances and future perspectives

Antimicrobial resistance represents one of the most urgent global health threats, necessitating a paradigm shift in antimicrobial susceptibility testing (AST) to ensure timely and targeted therapy. Conventional methods, although clinically standardized, suffer from long turnaround times (24–72 h), which delay treatment decisions and contribute to the overuse of broad-spectrum antibiotics. To solve this issue, microfluidic platforms are redefining AST by miniaturizing assays, reducing analysis times to mere hours, and minimizing sample consumption. Recent advances can be broadly categorized into channel-based, droplet-based, and integrated systems, which leverage diverse detection strategies including optical, electrical, and label-free approaches. Channel-based devices provide precise environmental control for direct microscopic observation and stable antibiotic gradient generation, while droplet-based platforms enable massive parallelization at the single-cell level, capturing heteroresistance and phenotypic diversity. Integrated systems increasingly combine microfluidics with smartphones, automation, and artificial intelligence (AI)-driven analytics, thereby accelerating the transition toward point-of-care testing. Beyond speed and throughput, microfluidic AST is also moving toward personalized diagnostics, incorporating direct-from-sample testing, host–pathogen coculture models, and machine learning-assisted image analysis to tailor therapy to individual patients. Despite challenges in standardization, complex sample handling, and regulatory approval, the convergence of advanced materials, automation, and AI with microfluidic platforms positions microfluidic AST as a cornerstone technology for the next generation of infectious disease management and personalized antimicrobial therapy.