Vat Photopolymerization of CeO-Incorporated Hydrogel Scaffolds with Antimicrobial Efficacy.

We herein demonstrate the utility of gelatin methacryloyl (GelMA)/poly(ethylene glycol) diacrylate (PEGDA)-cerium oxide (CeO) hydrogel inks for manufacturing hydrogel scaffolds with antimicrobial efficacy by vat photopolymerization. For uniform blending with GelMA/PEGDA hydrogels, CeO nanoparticles with a round shape were synthesized by the precipitation method coupled with calculation at 600 °C. In addition, they had highly crystalline phases and the desired chemical structures (oxidation states of Ce and Ce) required for outstanding antimicrobial efficacy. A range of GelMA/PEGDA-CeO hydrogel scaffolds with different CeO contents (0% /, 0.1% /, 0.5% /, 1% /, and 5% / with respect to distilled water content) were manufactured. The photopolymerization behavior, mechanical properties, and biological properties (swelling and biodegradation behaviors) of hydrogel scaffolds were characterized to optimize the CeO content. GelMA/PEGDA-CeO hydrogel scaffolds produced with the highest CeO content (5% /) showed reasonable mechanical properties (compressive strength = 0.56 ± 0.09 MPa and compressive modulus = 0.19 ± 0.03 MPa), a high swelling ratio (1063.3 ± 10.9%), and the desired biodegradation rate (remaining weight after 28 days = 39.6 ± 2.3%). Furthermore, they showed outstanding antimicrobial efficacy (the number of colony-forming units = 76 ± 44.6 (×10)). In addition, macroporous GelMA/PEGDA-CeO hydrogel scaffolds with tightly controlled porous structures could be manufactured by vat photopolymerization.