AVS 60th International Symposium and Exhibition
    Surface Science Wednesday Sessions
       Session SS+NS-WeM

Paper SS+NS-WeM6
A New Effect of Nanoconfinement on Chemical Equilibrium: Theory and Experimental Evidence

Wednesday, October 30, 2013, 9:40 am, Room 201 A

Session: Nanostructures: Reactivity & Catalysis
Presenter: L. Rubinovich, Ben-Gurion University of the Negev, Israel
Authors: L. Rubinovich, Ben-Gurion University of the Negev, Israel
M. Polak, Ben-Gurion University of the Negev, Israel
Correspondent: Click to Email

Recently1 we predicted that when a reaction involving a small number of molecules occurs in a nanometric-scale domain entirely segregated from the surrounding media, the nanoconfinement can shift the position of equilibrium toward products via reactant-product reduced mixing. In this talk, we demonstrate how most-recently reported single molecule fluorescence measurements of partial hybridization of ssDNA confined within nanofabricated chambers provide the first experimental confirmation of this entropic nanoconfinement effect. Thus, focusing separately on each occupancy-specific equilibrium constant, quantitatively reveals extra stabilization of the product upon decreasing the chamber occupancy or size.2 Namely, the DNA hybridization under nanoconfined conditions is significantly favored over the identical reaction occurring in bulk media with the same reactant concentrations. This effect, now directly verified for DNA, can be relevant to actual biological processes, as well as to reactions occurring on nanoparticle surfaces, and within molecular capsules, nanotubes, or other functional nanospaces.

1. Polak, M.; Rubinovich, L. Nano Lett. 2008, 8 (10), 3543−3547.

2. Rubinovich, L.; Polak, M. Nano Lett. 2013, DOI: 10.1021/nl4008198.