Fluorescent and catalytic gold nanoclusters engineered for bacterial detection and eradication

Detecting and eliminating bacteria efficiently is crucial to combat equipment contamination. Conventional methods are expensive, time-consuming, and incapable of simultaneous detection and killing, thereby resulting in rapid bacterial multiplication posing a major threat to public health. In this study, we present aptamer-modified gold nanoclusters (Apt-Au NCs) exhibiting excellent fluorescent and catalytic properties that combine both bacterial detection and antibacterial activity. Thiol-modified aptamer functionalized on Au NCs specifically binds to bacterial surfaces, enabling the simultaneous identification and eradication of bacteria. The specific binding of bacteria enhances the fluorescent signal of Apt-Au NCs, exhibiting a linear detection range from 10 to 10 5 CFU/mL with a LOD of 29.6 CFU/mL. The Apt-Au NCs exhibit peroxidase-like behavior, resulting in almost complete eradication of bacterial viability. Furthermore, when applied to hydrogel, Apt-Au NCs maintain their ability to detect and combat bacterial contamination, enabling fluorescence identification of bacterial presence and elimination. This work provides a promising platform for the simultaneous detection and eradication applicable to equipment-related surfaces, which holds great potential for ensuring public safety in food and medical industries.