Single molecule force spectroscopy on the modulation of hydrophobic interactions by locally immobilized polar groups

Our experimental program seeks to provide fundamental insights into the effects of chemical heterogeneity on hydrophobic interactions at surfaces. It build from our recent discovery that ions immobilized adjacent to non-polar domains can dramatically increase or decrease the strength of hydrophobic interactions, with the effect strongly dependent on the specific ion type [1,2].  Specifically, divergent effects of proximally immobilized cations were found in single-molecule force measurements using conformationally-stable β-amino acid oligomers (β-peptides) that generate precise nanopatterns of non-polar and either Am- or Gdm-bearing subunits (β3-homolysine and β3-homoarginine residues, respectively) [1].

Recent Publications:

1. "Interaction of the Hydrophobic Tip of an Atomic Force Microscope with Oligopeptides Immobilized Using Short and Long Tethers." Ma, C.D.; Acevedo-Vélez, C.; Wang, C.; Gellman, S.H.; Abbott, N.L. Langmuir 2016, 32, 2985.

2. “Modulation of hydrophobic interactions by proximally immobilized ions.” Ma CD, Wang C, Acevedo-Vélez C, Gellman SH, Abbott NL.Nature 2015, 517, 347.

3. "Single-molecule force spectroscopy of β- peptides that display well-defined three-dimensional chemical patterns.", Acevedo-Velz, C.; Andre, G.; Dufrene, Y.F.; Gellman, S.H.; Abbott, N.L., J. Am. Chem. Soc.2011, 133, 3981-3988.