August 11-14th at the Crowne Plaza Hotel in downtown Knoxville, TN

Can Martini coarse-grained models capture antifouling behavior of polyzwitterionic brush coatings?

Not scheduled

20m

Crowne Plaza Knoxville

Poster Only

Speaker

Christopher Walker (Oak Ridge National Laboratory)

Description

Biofouling has widespread implications for everyday materials, including biomedical devices, personal protective equipment, and marine coatings, leading to performance degradation and high costs. Polyzwitterionic brush coatings are known to exhibit antifouling behavior due largely to a strongly coupled hydration layer, yet the detailed mechanism is not fully understood. Moreover, only a handful of polymer chemistries have thus far been identified as highly antifouling.

Molecular dynamics (MD) simulations are a vital tool for studying polymer-protein interactions at angstrom-scale resolution, enabling both screening of polymer chemistries for antifouling properties, and interpreting experimental results indicating antifouling behavior. Coarse-grained (CG) simulations, in which atoms are grouped into effective interaction sites, lead to substantial gains in computational efficiency and allow for accessing microsecond timescales in large polymer systems.

In this work we present new Martini CG models for a series of polyelectrolyte and polyzwitterion chemistries compatible with Martini 2 polarizable water. CG brush models are validated by comparing density profiles and pair correlation functions against all-atom systems. Finally, adsorption free energies of lysozyme into the brushes are computed via metadynamics. We assess whether the models can capture the expected effects of brush chemistry and salt on antifouling behavior.

Acknowledgements:
This work was supported by the U. S. Department of Energy Office of Science FWP ERKCZ64, Structure Guided Design of Materials to Optimize the Abiotic-Biotic Material Interface, as part of the Biopreparedness Research Virtual Environment (BRaVE) initiative. This work was performed at the Center for Nanophase Materials Sciences, a US Department of Energy Office of Science User Facility operated at Oak Ridge National Laboratory. This research used resources of the Oak Ridge Leadership Computing Facility (OLCF) at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725.