Intelligent Microneedles Patch with Wireless Self-Sensing and Anti-Infective Actions

Traditional microneedle (MN) technology offers unique advantages in treating wound infections; however, its single-function design lacks the capability for real-time monitoring of wound conditions, often resulting in uncontrolled drug release. Herein, an anti-infective and intelligent MN patch (SP-CSMN) integrating three functional modules is developed, including temperature monitoring, Bluetooth wireless communication, and responsive drug release. The patch employed chitosan (CS) as a porous substrate, filled with temperature-sensitive poly(N-isopropylacrylamide) (PNIPAM) to encapsulate and release the antibiotic rifampicin. With the integrated sensing chip, SP-CSMN enabled continuous temperature monitoring and real-time feedback via smartphone Bluetooth communication. When the wound temperature exceeds 36.5 °C for 6 h, the system can automatically identify the infection occurrence and activate the heating module to trigger PNIPAM contraction, triggering rifampicin release. This self-sensing and intelligent release cycles can repeat throughout its life-cycle. The SP-CSMN demonstrated precisely temperature-induced drug release and enhanced antibacterial activities against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in vitro. Furthermore, it sensitively monitored wound temperature changes in infected mice and significantly accelerated wound healing via controlled drug delivery. This advanced MN system offers a promising solution for efficient management of bacterial wound infections.