Hybrid Methacrylated Gelatin and Hyaluronic Acid Hydrogel Scaffolds. Preparation and Systematic Characterization for Prospective Tissue Engineering Applications

Abstract

Hyaluronic acid (HA) and gelatin (Gel) are major components of the extracellular matrix of different tissues, and thus are largely appealing for the construction of hybrid hydrogels to combine the favorable characteristics of each biopolymer, such as the gel adhesiveness of Gel and the better mechanical strength of HA, respectively. However, despite previous studies conducted so far, the relationship between composition and scaffold structure and physico-chemical properties has not been completely and systematically established. In this work, pure and hybrid hydrogels of methacroyl-modified HA (HAMA) and Gel (GelMA) were prepared by UV photopolymerization and an extensive characterization was done to elucidate such correlations. Methacrylation degrees of ca. 40% and 11% for GelMA and HAMA, respectively, were obtained, which allows to improve the hydrogels’ mechanical properties. Hybrid GelMA/HAMA hydrogels were stiffer, with elastic modulus up to ca. 30 kPa, and porous (up to 91%) compared with pure GelMA ones at similar GelMA concentrations thanks to the interaction between HAMA and GelMA chains in the polymeric matrix. The progressive presence of HAMA gave rise to scaffolds with more disorganized, stiffer, and less porous structures owing to the net increase of mass in the hydrogel compositions. HAMA also made hybrid hydrogels more swellable and resistant to collagenase biodegradation. Hence, the suitable choice of polymeric composition allows to regulate the hydrogels´ physical properties to look for the most optimal characteristics required for the intended tissue engineering application.

Development of functional hybrid scaffolds for wound healing applications

“…SEM images confirmed that an increase in the HA weight percentage in the scaffolds gives rise to more rugged void walls for the hybrid 3% HCS-2% HHA scaffold than those observed for the hybrid 3% HCS-1% HHA hydrogel, that is, a very porous structure but with more disorganized pores of mean sizes of ca. 30 μm is still retained ( Figure 4 G), in agreement with the structure observed in other hybrid hydrogel scaffolds containing HA ( Chang et al., 2013 ; Gilarska et al., 2018 ; Velasco- Rodriguez et al., 2021 ). Conversely, the use of LHA in the scaffold composition does not seem to have a great impact on the scaffold structure.…”

Genipin-Crosslinked, Proteosaccharide Scaffolds for Potential Neural Tissue Engineering Applications

“…Therefore, it can be concluded that the combination of the two hydrophilic polymers results in lower thermal stability, which is slightly improved by crosslinking one of the polymers, that being gelatin in this study. Thermal stability would be significantly improved by modifying HA, using thiolation or methacrylation [32,33].…”

3D-bioprinted peptide coupling patches for wound healing

“…At the same time, the Young's modulus of 15% GelMA is about 10 ​kPa [ 26 ], and its mechanical properties are weaker than those of native skin tissues [ 27 ]. To overcome this limitation, hybrid GelMA/HAMA hydrogels were fabricated, demonstrating improved physical properties [ 28 ]. Furthermore, in mixed GelMA hydrogels, 5% HAMA showed increased mechanical strength compared to 1% HAMA [ 28 ].…”

“…To overcome this limitation, hybrid GelMA/HAMA hydrogels were fabricated, demonstrating improved physical properties [ 28 ]. Furthermore, in mixed GelMA hydrogels, 5% HAMA showed increased mechanical strength compared to 1% HAMA [ 28 ]. Therefore, in subsequent experiments, 15% GelMA and 5% HAMA were used.…”