Wearable battery-free smart bandage with peptide functionalized biosensors based on MXene for bacterial wound infection detection

Wound infection is a life-threatening healthcare issue that can cause severe pain, sepsis, and even amputation. Herein, to address the challenges of point-of-care wound analysis, a battery-free, wireless, and wearable smart bandage was developed for bacterial virulence factors detection. Typical biomarkers, sortase A and pyocyanin, corresponding to two major types of bacterial infection, Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa, were detected with electrochemical differential pulse voltammetry. Ti3C2Tx MXene was applied to the electrode to enhance the sensitivity. Pyocyanin could transfer electrons with the electrode for sensing due to its redox characteristics, while a peptide labeled with the electroactive ferrocene was customized for the specific recognition of sortase A. The integration of near field communication module realized wireless energy harvesting and data transmission with the smartphone. The fully integrated system demonstrated good linearity and high sensitivity, with wide detection ranges of 1 pg/mL to 100 ng/mL for sortase A, and 1 μM to 100 μM for pyocyanin. Furthermore, the animal studies indicated the effectiveness of the smart bandage for multi-biomarker profiling of wound. This wearable system provides a noninvasive, convenient, and efficient platform for in situ bacterial virulence factors detection, offering great potential for the management of the infected wound.