Polysaccharide-based microneedles for advanced wound healing: recent advances and future challenges

Wound healing is a complex, dynamic, and tightly regulated biological process orchestrated by intricate cellular signalling pathways. Both acute and chronic wounds present significant therapeutic challenges, driving the demand for innovative and effective treatment modalities. The existing treatment options fail to address the challenges associated with conventional dosage forms, such as poor skin penetration and low bioavailability. Microneedle (MN) technology has emerged as a minimally invasive, highly efficient platform for localised drug delivery, offering the potential to accelerate and enhance tissue repair. Among the diverse materials investigated for MN fabrication, polysaccharide-based biodegradable polymers have attracted particular interest owing to their exceptional biocompatibility, biodegradability, and intrinsic biological activities. This review provides an in-depth analysis of natural polysaccharides (e.g., chitosan, alginate, hyaluronic acid) and synthetic polysaccharides (e.g., polylactic acid, polycaprolactone, PLGA) employed in MN-assisted wound healing. In this review, authors also highlighted the roles of polysaccharides in modulating key phases of the healing cascade, namely inflammation, proliferation, and remodelling, via critical signalling pathways such as NF-κB, PI3K/Akt, and TGF-β. These multifunctional properties of marine, plants, and animal-derived polysaccharides are also explored, particularly their antibacterial, anti-inflammatory, and pro-angiogenic effects when incorporated into MN systems. By enabling targeted, sustained, and responsive therapeutic delivery, polysaccharide-based MNs represent a transformative strategy for advanced wound care. The future research should focus on scalable manufacturing techniques, the integration of stimuli-responsive elements, and robust clinical evaluation to unlock the full potential of these polysaccharide-mediated microneedles as next-generation wound healing platforms.