| AVS 54th International Symposium | |
| Biomaterial Interfaces | Tuesday Sessions |
| Session BI-TuP |
| Session: | Biomaterials Interfaces Poster Session |
| Presenter: | J.C. Hower, University of Washington |
| Authors: | J.C. Hower, University of Washington Y. He, University of Washington S. Jiang, University of Washington |
| Correspondent: | Click to Email |
While significant advances in biocompatible and environmentally benign materials have been made, one of the remaining challenges is to understand surface resistance to protein adsorption. Significant experimental efforts have produced only a small number of nonfouling materials and coatings. Moreover the mechanisms of protein resistance are poorly understood and a majority of new material breakthroughs are made fortuitously. Molecular simulations can aide in material development. By simulating in-silico, one can perform costly experimentation after candidates are selected by initial screening. Molecular simulations also provide access to interactions at the protein-surface-solution interface. We have performed extensive work quantifying the repulsive forces that nonfouling surfaces generate on proteins and analyzing the cause of these forces. Yet, the thermodynamic criterion of adsorption or resistance is the change in free energy as a protein approaches a surface. In this work, molecular simulations were used to calculate the free energy change as model peptides in solution approach surfaces of varying nonfouling ability and to develop simulation-based evaluation criteria. The simulations were supported by protein adsorption experiments. By combining simulations and experiments we verified our simulations and evaluated the relative influence of the surface and hydrating water on the process. This combined approach provides feedback on our simulation parameters and a deeper understanding of the mechanisms of protein resistance and adsorption. Our research has demonstrated a strong link between surface hydration and non-fouling ability. Thus simulations and experiments were conducted to evaluate the hydration of functional moieties representing a wide range of nonfouling abilities. The extent of hydration of biologically relevant functional groups, like oligo-ethylene glycol and sugar alcohols, was evaluated by calculating the partial molar volume change due to hydration. This data was then compared to protein adsorption to self-assembled monolayer surfaces presenting the same functional groups. By using a simple measurement of hydration, it is possible to rapidly screen candidate non-fouling moieties. By combining molecular simulations and experimental techniques, we are able to develop a fundamental description of the interactions present at the molecular and macro scale. This in turn supports rational material design based on desired molecular function.