Three-dimensional printing of collagen and hyaluronic acid scaffolds with dehydrothermal treatment crosslinking

Abstract

Scaffolds of collagen and collagen with hyaluronic acid were fabricated using 3D printing and crosslinked bydehydrothermal treatment. Rheological measurements of both these dispersions revealed high values of viscosityand a shear thinning behaviour. Fourier transform spectrometry indicated an increased amide bone formationwhen hydrothermal treatment was applied, with scanning electron microscopy revealing different pore sizedistributions in the scaffolds with micro- and nano-fibres. The cross-linking treatment in both scaffolds improvedresistance to collagenase and elastic mechanical properties, whereas those with hyaluronic acid showed higherresistence solubilization than scaffolds without treatment in a short time at physiological conditions. Theswelling ratio of all crosslinked scaffolds decreased, but this treatment prevented disintegration of collagen withhyaluronic acid scaffolds in aqueous medium. Additionally, the cytotoxicity for Vero and NIH3T3 cells showedthat the collagen scaffold extracts were not cytotoxic, whereas extracts from collagen plus hyaluronic acidcrosslinked scaffolds were cytotoxic only for Vero cells. In vitro evaluation using BJ cells from human skindemonstrated that all scaffolds had the ability to support cell attachment and proliferation. These resultsrevealed that the properties of the 3D printed scaffolds based on collagen and hyaluronic acid could be modifiedby dehydrothermal treatment, with the materials obtained provide the support required in tissue engineering.