Fibrillogenesis of acrylic acid-grafted-collagen without self-assembly property inspired by the hybrid fibrils of xenogeneic collagen.

Along with advancements in both protein and chemistry science, the chemical modification of proteins is attracting more and more attention. More specifically, the attachment of polymers or reactive moieties into collagen offers a method to add novel functions to this protein. However, the fibrillogenesis of the modified collagen with high grafting density cannot always be achieved. Here, inspired by the hybrid fibrils of xenogeneic collagen, fibrillogenesis of acrylic acid-grafted-collagen (AAc-g-Col) without self-assembly property was achieved by the induction of natural collagen (Col). The step-by-step co-assembly process of AAc-g-Col and Col was confirmed by turbidity assay. The formation of Col/AAc-g-Col hybrid fibrils was verified by TEM since the acryloyl groups of the hybrid fibrils were labelled using HS-AuNPs based on the Michael addition. Moreover, rheology, SEM, and MTT assays revealed that the fibrillary structures and biocompatibility of the Col/AAc-g-Col hydrogel were comparable to that of the Col hydrogel, although they presented a lower viscoelasticity.