Studying the Mechanical and Biological Properties of Alginate-Based Hydrogels For Three Dimensional Bioprinting Applications

In the present research, biodegradable alginate hydrogels with controllable mechanical properties were engineered for biomedical applications. for this purpose, alginate was oxidized to make it more prone to hydrolytic degradation. afterward, the methacrylation of the oxidized alginate was performed to produce hydrogels that can be photo-crosslinked under visible light. a non-toxic eosin y-based photo-initiation system for the chemical crosslinking of hydrogels was employed. the effect of changing the biopolymer crosslinking density by varying the degree of alginate methacrylation was quantified through the examination of hydrogel swelling and elastic moduli. a combination of ionic- and photo-crosslinking was employed to prepare alginate hydrogels with tunable mechanical properties. also, the versatility of oma macromers for the preparation of hydrogels through independent crosslinking chemistries was demonstrated. moreover, the chronological effect of ionic- and photo-crosslinking on the mechanical properties of the final hydrogel was investigated using rheometry techniques. finally, the rheological properties of oma hydrogels as a bio-ink for 3d bioprinting were optimized. the increase in the degree of methacrylation lead to a decrease in swelling ratio, increase in cross-linking density, and elastic moduli of the final hydrogel. in comparison to the hydrogels prepared by ionic crosslinking followed by uv photopolymerization, the hydrogels prepared by uv photo-polymerization followed by ionic-crosslinking demonstrated a stiffer gel network.

Studying the mechanical and biological properties of alginate-based hydrogels for three dimensional bioprinting applications

In the present research, biodegradable alginate hydrogels with controllable mechanical properties were engineered for biomedical applications. For this purpose, alginate was oxidized to make it more prone to hydrolytic degradation. Afterward, the methacrylation of the oxidized alginate was performed to produce hydrogels that can be photo-crosslinked under visible light. A non-toxic Eosin Y-based photo-initiation system for the chemical crosslinking of hydrogels was employed. The effect of changing the biopolymer crosslinking density by varying the degree of alginate methacrylation was quantified through the examination of hydrogel swelling and elastic moduli. A combination of ionic- and photo-crosslinking was employed to prepare alginate hydrogels with tunable mechanical properties. Also, the versatility of OMA macromers for the preparation of hydrogels through independent crosslinking chemistries was demonstrated. Moreover, the chronological effect of ionic- and photo-crosslinking on the mechanical properties of the final hydrogel was investigated using rheometry techniques. Finally, the rheological properties of OMA hydrogels as a bio-ink for 3D bioprinting were optimized. The increase in the degree of methacrylation lead to a decrease in swelling ratio, increase in cross-linking density, and elastic moduli of the final hydrogel. In comparison to the hydrogels prepared by ionic crosslinking followed by UV photopolymerization, the hydrogels prepared by UV photo-polymerization followed by ionic-crosslinking demonstrated a stiffer gel network.