Synthesis and Characterization of Gelatin Methacryloyl: Introducing Chemistry Students to the Applications of Hydrogels in Medicine

Many undergraduate chemistry and biochemistry students pursue careers in healthcare. Biomaterials, designed to harmonize with the complexity of the human body, have become increasingly significant in medicine as implants, drug delivery vehicles and tissue scaffolds. We believe it is essential that undergraduates are exposed to biomaterial synthesis and characterization before they pursue further graduate education or a career in pharmaceuticals. In this laboratory experiment, we argue that gelatin methacryloyl (GelMA) is a biomacromolecule well suited to being synthesized and characterized in an undergraduate laboratory. We detail a protocol to graft methacrylic anhydride (MAAnh) to the gelatin backbone in a heated, buffered solution and then provide three synergistic characterization assays: NMR spectroscopy, a TNBS assay, and a Fe(III)-hydroxamic acid-based assay. NMR analysis allowed the students to determine if they had achieved a successful synthesis, and the latter two colorimetric assays quantified modifications of amino and hydroxyl groups. We found that our students successfully synthesized purified GelMA, and quantiatively determined its final molecular structure. Students indicated that the study reinforced their chemistry laboratory skills, introduced them to a new discipline, and increased their interest in the medicinal applications of materials.