Microfluidic electrospray photo-crosslinkable κ-Carrageenan microparticles for wound healing

When organs, especially external organs are injured, pathogens and excessive water loss can threaten the wound healing process and cause local irreversible tissue damage. Here, novel natural κ-Carrageenan microparticles (MPs) able to deliver bioactive proteins and small molecules to the wound surface for promoted regeneration were developed using microfluidic electrospray. The side chains of κ-Carrageenan were modified with methacrylate pendant groups to make the monomer photonic cross-linkable. By changing the concentration of methacrylated-κ-Carrageenan, different porosities of MPs with controllable drug loading were achieved. The size of the MPs can also be tailored by adjusting the voltage of the applied electric field. Vascular endothelial growth factor (VEGF) and antimicrobial peptides Eumenitin were co-loaded into the microparticles (VEGF-Eumenitin-MPs) and released sustainedly in phosphate-buffered saline. The VEGF-Eumenitin-MPs had high biocompatibility and intensive antibacterial activities for bacteria. Furthermore, the antibacterial and angiogenetic properties of the VEGF-Eumenitin-MPs were demonstrated in a infectious wound model and the chronic wound healing process was significantly enhanced in vivo. Therefore, the developed porous MPs with sustained drug release properties have the potential to serve as a platform to deliver bioactive proteins and small molecules to the wound surface for promoted regeneration.