Biomimetic wet-stable fibres via wet spinning and diacid-based crosslinking of collagen triple helices

One of the limitations of electrospun collagen as bone-like fibrous structure is the potential

collagen triple helix denaturation in the fibre state and the corresponding inadequate wet

stability even after crosslinking. Here, we have demonstrated the feasibility of accomplishing

wet-stable fibres by wet spinning and diacid-based crosslinking of collagen triple helices,

whereby fibre ability to act as bone-mimicking mineralisation system has also been explored.

Circular dichroism (CD) demonstrated nearly complete triple helix retention in resulting wetspun

fibres, and the corresponding chemically crosslinked fibres successfully preserved their

fibrous morphology following 1-week incubation in phosphate buffer solution (PBS). The

presented novel diacid-based crosslinking route imparted superior tensile modulus and

strength to the resulting fibres indicating that covalent functionalization of distant collagen

molecules is unlikely to be accomplished by current state-of-the-art carbodiimide-based

crosslinking. To mimic the constituents of natural bone extra cellular matrix (ECM), the

crosslinked fibres were coated with carbonated hydroxyapatite (CHA) through biomimetic

precipitation, resulting in an attractive biomaterial for guided bone regeneration (GBR), e.g.

in bony defects of the maxillofacial region.