Carbon Dots Crosslinked Egg White Hydrogel for Tissue Engineering

Egg white (EW)-derived hydrogels hold promise as biomaterials for in vitro cell culture due to their ability to mimic the extracellular matrix. However, their highly cross-linked structures restrict their potential for in vivo applications, as they are unable to integrate dynamically with tissues before degradation. In this study, this limitation is addressed by introducing carbon dots (CDs) as cross-linking agents for EW in a dilute aqueous solution. The resulting CDs-crosslinked EW hydrogel (CEWH) exhibits tensile strength comparable to that of skin tissue and features a large pore structure that promotes cell infiltration. Subcutaneous implantation of CEWH demonstrated excellent integration with surrounding tissue and a degradation rate aligned with the hair follicles (HFs) regeneration cycle. This allows the long-term regeneration and establishment of an M2 macrophage-dominated immune microenvironment, which in turn promotes the re-entry of HFs into the anagen phase from the telogen phase. Additionally, CEWH demonstrated potential as a wound dressing material. Overall, this study paves the way for utilizing EW as a versatile biomaterial for tissue engineering.