Fiber-Reinforced Silk Microneedle Patches for Improved Tissue Adhesion in Treating Diabetic Wound Infections

Microneedles (MNs) with unique three-dimensional stereochemical structures are suitable candidates for tissue fixation and drug delivery. However, existing hydrogel MNs exhibit poor mechanical properties after swelling and require complex preparation procedures, impeding their practical application. Hence, we engineered chitosan fiber-reinforced silk fibroin MN patches containing epigallocatechin gallate (SCEMN). A formic acid–calcium chloride system was introduced to fabricate hydrogel MNs with excellent inherent adhesion, and the incorporation of chitosan fiber as a reinforcing material enhanced mechanical strength and viscosity, thereby increasing the physical interlocking with tissue and the ability to maintain shape. The SCEMN with a lower insertion force firmly adhered to porcine skin, with a maximum detachment force of 11.98 N/cm². Additionally, SCEMN has excellent antioxidant and antibacterial properties, facilitates macrophage polarization from M1 to M2, and demonstrates superior performance in vivo for diabetic wound repair compared with the commercial product Tegaderm™. This study represents the first trial of fiber-reinforced hydrogel MNs for robust tissue adhesion. Our findings underscore the significance of this innovative approach for advancing MN technology to enhance tissue adhesion and accelerate wound healing.

Graphical Abstract