Institution: | 1. School of Engineering, Brown University, Providence, Rhode Island, USA
Center for Biomedical Engineering, Brown University, Providence, Rhode Island, USA;2. REFINE Lab, University of Connecticut, Storrs, Connecticut, USA;3. School of Engineering, Brown University, Providence, Rhode Island, USA
Center for Biomedical Engineering, Brown University, Providence, Rhode Island, USA
Institute for Molecular and Nanoscale Innovation, Brown University, Providence, Rhode Island, USA;4. School of Engineering, Brown University, Providence, Rhode Island, USA |
Abstract: | Developing optimized hydrogel products requires an in-depth understanding of the mechanisms that drive hydrogel tunability. Here, we performed a full 4 × 4 factorial design study investigating the impact of gellan, a naturally derived polysaccharide (1%, 2%, 3%, or 4% w/v) and CaCl2 concentration (1, 3, 7, or 10 mM) on the viscoelastic, swelling, and drug release behavior of gellan hydrogels containing a model drug, vancomycin. These concentrations were chosen to specifically provide insight into gellan hydrogel behavior for formulations utilizing polymer and salt concentrations expanding beyond those commonly reported by previous studies exploring gellan. With increasing gellan and CaCl2 concentration, the hydrogel storage moduli (0.1–100 kPa) followed a power-law relationship and on average these hydrogels had higher liquid absorption capability and greater total drug release over 6 days. We suggest that the effects of gellan and CaCl2 concentration and their interactions on hydrogel properties can be explained by various phenomena that lead to increased swelling and increased resistance to network expansion. |