(710e) Molecular Simulation of Hydration of Zwitterion

Zwitterionic materials are an important new type of biomaterials for biological and chemical applications such as drug delivery, marine coating and molecular sensing. One important research topic of zwitterions is to understand their structure-property relationship. In this work, we carried out a series of quantum calculations and molecular simulations to study the zwitterionic strength and hydration of zwitterion molecules with various negatively and positively charged groups, distance between charged groups and additional groups. We investigated the electrostatic potential surface of the molecules and the coordination number, orientation distributions and residence dynamics of water molecules around the zwitterion molecules. We also investigated the preferential association of various zwitterions with ions. The simulation results illustrate the effect of distance between charged groups and additional groups on the zwitterionic strength of molecules with various charged groups, as well as their hydration. The correlation we observed between the charged group distance/addtional groups and the hydration of zwitterion offers a strategy for the rational design of zwitterionic materials.