Schematic illustrations of the preparation and application of the niacin MOFs encapsulated microcapsules. (a) The microcapsules generation process from the microfluidic electrospray. (b) The niacin MOFs encapsulated microcapsules applied to wound healing by airbrush. The alginate shell could be degraded by bacteria and body fluid, which released calcium ions and accelerated the release of MOFs. (c) The antibacterial and antioxidant capabilities of the released copper and zinc ions.