3D-printed barbed microneedle electrodes for biosensing and drug delivery in wound management

Chronic wounds represent a major global healthcare burden, demanding integrated solutions for both continuous wound monitoring and on-demand therapeutic intervention. In this work, we present monolithic barbed microneedles (3D-BMN) for wound impedance sensing and barbed hollow microneedles (3D-BHMN) for drug delivery, fabricated with high-precision projection micro-stereolithography (PμSL) 3D printing. Inspired by natural barbed structures like bee stingers, the barbed geometry balances penetration efficiency with mechanical interlocking, enabling stable anchorage to wound dressings. Conductivization with Ag/AgCl and AuNPs imparts robust electrochemical performance, allowing accurate monitoring of wound impedance, which correlates with wound status. 3D-BHMN integrates an ultrasonic atomizer for efficient drug delivery. A closed-loop feedback system couples 3D-BMN and 3D-BHMN, forming a closed-loop system for on-demand delivery of therapeutic agents modulated by the sensed impedance value that aligns with the dynamic wound status. This integrated platform advances smart wound management by combining diagnostics and therapeutics, offering broad translational potential.