New Insights into Hydrophobic Interactions Encoded by Chemical Nanopatterns

The structuring of water near non-polar molecular fragments or surfaces mediates cohesive interactions (so-called hydrophobic interactions) that underlie a broad range of biophysical and materials-related phenomena.  Substantial progress has been made during the past decade towards understanding hydrophobic interactions in simple model systems, but in most biological and technological contexts, non-polar domains are found in close proximity to polar and charged functional groups.  We are using conformationally-stable b-amino acid oligomers, and single-molecule force measurements to elucidate hydrophobic interactions encoded by specific chemical nanopatterns. These measurements reveal, for example, that ions immobilized adjacent to non-polar domains can substantially increase or decrease the strength of hydrophobic adhesion, with the effect strongly dependent on the specific ion type.  This understanding is providing a fresh starting point for molecular design in aqueous environments in a broad range of contexts.
 
Ma, C.D.; Wang, C.; Acevedo-Vélez, C.; Gellman, S.H.; Abbott, N.L., “Modulation of Hydrophobic Interactions by Proximally Immobilized Ions”, Nature, 517(7534), 347-443, 2015.

Bio: Nicholas Abbott received a Bachelor of Engineering (Chemical Engineering) from University of Adelaide, Australia in 1985, and a PhD in Chemical Engineering from Massachusetts Institute of Technology in 1991.  He was a postdoctoral fellow in the Chemistry Department of Harvard University from 1991-1993.  He is currently the Sobota Professor and Hilldale Professor of Chemical and Biological Engineering at University of Wisconsin-Madison, and the Director of the Wisconsin Materials Research Science and Engineering Center.  He is an elected Member of the US National Academy of Engineering and serves as Co-Editor-in-Chief of Current Opinion in Colloid and Interface Science.