Enzyme-Activated Near-Infrared Fluorescent Probe for Rapid and Precise Identification of Staphylococcus aureus-Induced Skin Infections.

Staphylococcus aureus (S. aureus) is a major opportunistic pathogen responsible for diverse skin and soft tissue infections, which may rapidly progress to severe or systemic infections if not promptly managed. Therefore, the rapid and precise identification of S. aureus infections is essential for timely clinical intervention. Herein, we report an enzyme-activatable, near-infrared (NIR) fluorescent probe (HD-G) for the specific detection and visualization of S. aureus by targeting its characteristic glycosidase, α-glucosidase (α-Glc). The probe exhibits high stability and excellent selectivity, enabling reliable detection of S. aureus in both planktonic and biofilm states, and effectively distinguishing it from other clinical pathogens. Moreover, HD-G demonstrates good biocompatibility and facilitates noninvasive, real-time, in situ imaging of S. aureus-related skin infections in vivo. Notably, it can differentiate live from dead S. aureus, making it suitable for monitoring infection progression and evaluating antibiotic efficacy. Collectively, HD-G is a responsive probe that provides reliable pathogen information to support accurate diagnosis and targeted treatment.