Robust self-pumping medical microneedle arrays by nanofiber-reinforced non-covalent cooperative networks

The directional management of exudate drainage and drug delivery assumes paramount importance in the realm of precision therapy for diabetic wounds. Drawing inspiration from the water-collecting and transporting abilities of cactus spines and the water-drinking behavior of spiny lizards, this work designed a robust self-pumping medical microneedle array composed of cellulose nanofibril-reinforced microneedles by non-covalent cooperative bond networks and a Janus backing layer with bidirectional fluid transport capability. Microneedles reinforced with nanofiber exhibit exceptional photothermal conversion efficiency while maintaining sufficient mechanical strength and toughness for epidermal penetration without deformation. The bidirectional Janus backing encompasses a drug delivery zone and a UV-reversibly induced exudate pumping/wettability maintenance zone, enabling staggered transport of the drug and exudates to guarantee long-term efficacy in sustained drug release, controlled exudate removal and microenvironment wettability maintenance. Crucially, it effectively combines broad-spectrum antibacterial, biofilm elimination, antioxidant, biocompatibility and anti-inflammatory functions with edema reduction in diabetic wounds, significantly accelerating the healing process. These findings present an innovative strategy for designing precision therapeutic materials with multimodal wound management capabilities.