A highly durable and biocompatible bionic collagen implant with exceptional anti-calcification and collagen regeneration capabilities for improved skin rejuvenation

Skin aging, a complex and inevitable biological process, considerably impacts an individual's physical appearance and overall well-being. While collagen-based implants hold potential for skin rejuvenation, their clinical application is limited by the poor durability of non-crosslinked implants and the negative impacts of crosslinking agents, such as cytotoxicity and calcification. Herein, we report a highly durable and biocompatible bionic collagen implant for superior skin rejuvenation with advanced anti-calcification characteristics and enhanced collagen regeneration. Utilizing biomimetic self-assembly and covalent crosslinking approach, we successfully created long-lasting and biomimetic collagen implants with densely-packed collagen fibers. Crosslinking of collagen fibers with a low concentration of N-hydroxysuccinimide activated suberic acid (NHS-SA) was highly efficient, resulting in complete crosslinking and thicker collagen fiber formation with a uniform network structure. Compared with glutaraldehyde-crosslinked collagen fibers, NHS-SA-crosslinked assembled collagen fibers (NACF) demonstrated considerably improved thermal stability and durability. Furthermore, the NACF implant exhibited superior biocompatibility, establishing NHS-SA crosslinked collagen fibers as a safer and more bioactive choice for implant applications. In mouse subcutaneous implant models, the NACF implant outperformed other collagen implants, demonstrating exceptional biocompatibility, effective collagen regeneration, and excellent anti-calcification potential. The NACF implant shows immense promise in collagen regeneration, offering considerable potential to advance skin rejuvenation therapies.