Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Synthesis and Characterization of Gelatin Methacrylate Hydrogel Microparticles for Biomedical Applications

Hydrogels are attractive biomaterials for tissue engineering, but size limits nutrient, oxygen, and drug transport, reducing their effectiveness. Hydrogel microparticles (HMPs) overcome these challenges by enhancing diffusion, injectability, and modular assembly, making them strong candidate for injectable scaffolds, drug carriers, and bioinks. Here, photocrosslinkable gelatin methacrylate (GelMA) hydrogels were synthesized and fabricated into microparticles of various sizes and shapes using 3D printing. Nuclear magnetic resonance confirmed successful methacrylation to gelatin backbone; rheometry measured the Young’s modulus to be ~60 ± 8 kPa; scanning electron microscopy revealed a porous architecture which allows cellular penetration. Swelling studies showed a ~380-fold increase in water retention compared to dry GelMA. The GelMA HMPs could be delivered through standard syringe needles without clogging, thereby supporting minimally invasive applications. Dissolution studies showed that HMPs degraded completely within 108 hours, while bulk hydrogel discs retained ~30% of their mass after 120 hours. Drug release studies established controlled release during the first week, in contrast to the delayed burst observed in bulk hydrogel discs. Live/Dead fluorescence further verified high viability, with predominantly live cells observed at both day 1 and day 3, indicating sustained growth within the HMP environment. These findings show that GelMA HMPs integrate tunable mechanics, high print fidelity, injectability, and favorable degradation and release profiles with strong cytocompatibility. Their ability to support cell viability and controlled drug delivery underscores their potential as injectable biomaterials for localized drug release for bone tissue engineering.