Crosslinking of 3D-printed collagen and chondroitin sulfate using 1,4-butanediol diglycidyl ether scaffolds to improve mechanical properties

Abstract

Collagen and chondroitin sulfate scaffolds were fabricated using 3D printing. Once printed, the scaffolds were divided into three groups. Two of these groups were subjected to a chemical crosslinking treatment with 1,4-butanedioldiglycidyl ether at different concentrations, while the last group remained uncrosslinked. Fourier Transform Infrared Spectrometry analysis indicated that for higher BDDE concentrations, the scaffolds showed higher cross-linking and denaturation degree. The crosslinking treatment enhanced the mechanical properties of the scaffolds, increasing their resistance to collagenase degradation and reducing their solubility under physiological conditions. Scanning electron microscopy and porosity test revealed that all the scaffolds showed an adequate range of porosity. Furthermore, according to ISO 10993-5, none of the three groups of scaffold extracts were cytotoxic, with cell viability greater than 70% using Vero cells. Finally, in vitro evaluation using BJ line cells from human skin demonstrated that all scaffolds allowed cell attachment and proliferation. Based on these results, the obtained scaffolds exhibited adequate characteristics and properties for their possible application in soft tissue engineering.