Biological activity of radiation-induced collagen-polyvinylpyrrolidone-PEG hydrogels

The synthesis of novel degradable hydrogels, with designable structures and good biocompatibility, produces attractive materials for use in connective tissue regeneration applications. However, the way in which human fibroblast cells respond to terpolymer hydrogels such as collagen-polyvinylpyrrolidone-polyethylene glycol (C-PVP-PEG) remains largely unknown. The aim of this study was to synthesize a gamma-radiation-induced C-PVP-PEG hydrogel and to evaluate its structure, morphology and cell viability in fibroblasts. Fourier transform infrared spectroscopy showed shifting of amide I to higher frequencies, as evidence of crosslinking produced by the radiation. The morphology of the hydrogel varied with the ratio of the polymers. We show a proposal for the mechanism of the hydrogel synthesis. The in vitro assessment of the hydrogels suggested that at 50 kGy, the presence of collagen decreased the cell viability for all samples, except for C-PVP. However, when PEG and PVP were added to the collagen, the cell's viability increased with respect to the irradiated collagen sample. (C) 2017 Elsevier B.V. All rights reserved.