A new shear-thinning nanocomposite hydrogel from GelMA-GO for soft tissue engineering

Abstract

The use of bio ink materials for fabricating scaffolds is the best option to replace aggressive surgery. This study aims to formulate an injectable hydrogel with suitable structural, mechanical, and rheological properties for tissue engineering applications. In this respect, gelatin methacrylate (GelMA) nanocomposites with different amounts of the modified graphene oxide nanoplates (0.25, 0.5, 0.75, and 1 wt%) were fabricated. The effect of the nanoplates on the structural, degradability, mechanical, rheological, and biological properties of the nanocomposites were evaluated. The results revealed that the functionalization of graphene oxide with dopamine (GOPD) resulted in the formation of a layer of polydopamine on the surface of the nanoplates, which developed the interaction of graphene oxide with GelMA chains. Adding GOPD to GelMA from 0 to 1 wt% decreased the water absorption (0.3 times) and its weight loss percentage (0.2 times). The addition of 0.5 wt% of GOPD to GelMA improved the compressive strength (7.5 times) and compressive modulus (7 times) compared to the GelMA hydrogel. Also, a similar amount of GOPD developed the thin shear properties of GelMA by three logarithmic units. Besides, the addition of the modified graphene oxide nanoplates to GelMA enhanced cell viability (93.26%) after 72 h of cell seeding. The proper behavior of the GelMA hydrogel with 0.5% GOPD, and its stability during the 3D printing process was confirmed. Accordingly, the injectable GelMA hydrogel containing dopamine-modified graphene oxide could be a proper candidate for tissue engineering expenditures.