Wet-spinnability and crosslinked fibre properties of two collagen polypeptides with varied molecular weight

Giuseppe Tronci; Ramya Sri Kanuparti; M. Tarik Arafat; Jie Yin; David J. Wood; Stephen J. Russell

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arXiv · 1507.07211

Wet-spinnability and crosslinked fibre properties of two collagen polypeptides with varied molecular weight

Giuseppe Tronci·Ramya Sri Kanuparti·M. Tarik Arafat·Jie Yin·David J. Wood·Stephen J. Russell

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Abstract

The formation of naturally-derived materials with wet stable fibrous architectures is paramount in order to mimic the features of tissues at the molecular and microscopic scale. Here, we investigated the formation of wet-spun fibres based on collagen-derived polypeptides with comparable chemical composition and varied molecular weight. Gelatin and hydrolysed fish collagen (HFC) were selected as widely-available linear amino-acidic chains of high and low molecular weight, respectively, and functionalised in the wet-spun fibre state in order to preserve the material geometry in physiological conditions. Wet-spun fibre diameter and morphology were dramatically affected depending on the polypeptide molecular weight, wet-spinning solvent (i.e. 2,2,2-Trifluoroethanol and dimethyl sulfoxide) and coagulating medium (i.e. acetone and ethanol), resulting in either bulky or porous internal geometry. Dry-state tensile moduli were significantly enhanced in gelatin and HFC samples following covalent crosslinking with activated 1,3 phenylenediacetic acid (Ph) (E: 726 +/- 43 - 844 +/- 85 MPa), compared to samples crosslinked via intramolecular carbodiimide-mediated condensation reaction (E: 588 +/- 38 MPa). Resulting fibres displayed a dry diameter in the range of 238 +/- 18 - 355 +/- 28 micron and proved to be mechanically-stable (E: 230 kPa) following equilibration with PBS, whilst a nearly-complete degradation was observed after 5-day incubation in physiological conditions.

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Giuseppe Tronci, Ramya Sri Kanuparti, M. Tarik Arafat, Jie Yin, David J. Wood, Stephen J. Russell. 2015-07-26. Wet-spinnability and crosslinked fibre properties of two collagen polypeptides with varied molecular weight. https://arxiv.org/abs/1507.07211

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