The ability to perturb large ensembles of molecules from equilibrium led to major advances in understanding reaction mechanisms in chemistry and biology. Here, we demonstrate the ability to control, measure, and make use of rapid temperature changes of fluid volumes that are commensurate with the size of single molecules. The method is based on the coupling of gold nanoparticles adjacent to a single nanometer-scale protein ion channel. Visible laser light incident on the nanoparticles causes the rapid and large increase of the solution temperature, which is measured by the change in the nanopore ionic conductance. The temperature shift affects the ability of individual molecules to enter into and interact with the nanopore. This technique could significantly improve sensor systems and force measurements based on single nanopores, thereby enabling a method for single molecule thermodynamics.
Citation: Proceedings of the National Academy of Sciences of the United States of America
Pub Type: Journals