Human-made biomaterials have the potential to unlock biological mysteries and transform human health. For a biomaterial to be useful, it must mimic the properties of living tissues and present cues to cells that generate a desired response (for example: to support loads, to grow, to produce a certain protein, to transform in some way, etc). A wide-range of materials are used in these applications and, in our shared work at HMC, we focus on soft tissue-models called hydrogels. Hydrogels are water-saturated polymer networks that are formed by mixing initially separate precursor-containing liquids to form solid materials (just like mixing resins when using epoxy).
Living tissues are complex; their complexity extends to their mechanical properties. By precisely controlling the composition and volume of each precursor fluid, it is possible to engineer hydrogels whose properties mimic those of living tissues. Hydrogels that are used for biological and biomedical applications are prepared by combining precursor liquids, but preparing these precursor mixtures is not a trivial task owing to their non-Newtonian properties (viscosity, elasticity, and pseudoplasticity). Therefore, through this project, we plan to evaluate the properties of a range of hydrogels and their precursors through oscillatory shear rheology. Through these measurements we aim to (1) determine the viscous, elastic, and pseudoplastic characteristics of hydrogel precursors and polymerized hydrogels, (2) determine and engineer the polymerization kinetics of precursor mixtures to inform hydrogel formulations, and (3) determine the storage and loss moduli of synthetic hydrogels and map their properties to those exhibited by biological tissues.
In undertaking this work, you join the team and jump right into evaluating material properties that inform the manufacture of synthetic biomaterials to form model tissues.
Check out this representative publication to learn more: https://doi.org/10.1016/j.progpolymsci.2019.01.003
Essay Prompt (~1 page total, due 24 hours prior to your scheduled interview): Why are you interested in working on this project? What skills do you hope to learn through this work? What skills do you bring to the group that support the project’s success?
As a member of this group, you would work on projects that collectively build knowledge at the intersection of fluid mechanics, bioengineering, and material engineering. Together, our work seeks to build tools and materials for evaluating biological function in benchtop models to uncover biological function.