Autotrophic photosynthetic 3D-bioprinting scaffolds for infected wound healing

An autotrophic, photosynthetic 3D-bioprinted core-shell scaffold (MA-SHC-PDA) has been developed for treating infected wounds. • The microalgae core enables sustained oxygen production under light, whereas the NIR-responsive PDA shell simultaneously triggers SHC carbon release and eradicates bacteria. • The MA-SHC-PDA scaffold alleviates hypoxia, suppresses infection, and accelerates infected wound healing. Bioengineered scaffolds have demonstrated significant potential in enhancing wound healing; while there remains ample room for improvement in mitigating localized hypoxia and preventing infections at wound sites. Here, we introduce a microfluidic in situ 3D bioprinted autotrophic photosynthetic scaffold for promoting the healing of infected wounds. The scaffold incorporates oxygen-producing microalgae (MA) along with its essential nutrients (agarose and sodium bicarbonate). Its exterior is coated with a photothermal material, forming a core-shell structured scaffold capable of autonomously cultivating microalgae while exhibiting excellent oxygen-producing activity and photothermal performance. By employing 3D bioprinting to apply this living autotrophic scaffold to infected wounds, we have achieved effective alleviation of local hypoxia, reduction of oxidative stress, and concurrent inhibition of bacterial infections. These combined effects significantly promoted neoangiogenesis, collagen accumulation, and tissue regeneration in infected wounds. Thus, our autotrophic photosynthetic 3D-bioprinting scaffolds hold substantial potential and value for clinical applications in wound healing.