PVA/alginate/maltose microneedle patch loaded with ZIF-8 and Cu-containing ZIF-8 for full-thickness wound healing: In...

An ideal microneedle array for promoting wound healing should possess mechanical strength, antibacterial, anti-inflammatory, and angiogenic properties. In this study, we developed a microneedle array with a PVA-Alginate-Maltose (PAM) matrix, within which Cu@ZIF-8 metal-organic framework nanoparticles were encapsulated for enhanced wound healing. We fabricated microneedle arrays containing 0%, 1%, and 3% w/w Cu@ZIF-8 (CZ), as well as a control group with 3% ZIF-8. The physical and chemical characteristics of both the nanoparticles and the microneedle arrays were analyzed using FESEM, XRD, FTIR, and EDS. The addition of maltose in the polymer matrix resulted in an increase in compressive force from 0.03 N/needle to 0.143 N/needle; by adding 3% Cu@ZIF-8, this value further increased to 0.156 N/needle, achieving a tip sharpness of 5.1 μm. In vitro studies demonstrated that the microneedles exhibited significant antibacterial activity, good biocompatibility, and an effective release rate of zinc and copper ions proved beneficial for wound closure. In vivo tests using immunohistochemical and histopathological analyses demonstrated that PAMCZ3% microneedles facilitated the highest levels of wound healing, epithelial layer regeneration, angiogenesis, and reduced scar formation. These findings suggest that the proposed PAMCZ3% microneedles could be applicable in clinical wound healing treatments.