Localized Joule heating produced by ion current focusing through micron-size holes
Posted by vviasnof on 04/29/2010
Newly published article in Applied Physics Letters
V.Viasnoff et al Appl Phys Lett, 96,163701, 2010
Collaboration Y.Tsori, H.Isambert, A.Meller
Focusing ionic current through a micron size hole separating 2 chambers may lead to a high local heating (up to 100°C). We exploit this effect to construct a set up that allows spatial determination of DNA melting profiles
Abstract: We provide an experimental demonstration that the focusing of ionic currents in a micron size hole
connecting two chambers can produce local temperature increases of up to 100 °C with gradients as large as 1 °K /micron. We find a good agreement between the measured temperature profiles and a finite elements-based numerical calculation. We show how the thermal gradients can be used to measure the full melting profile of DNA duplexes within a region of 40 microns. The possibility to produce even larger gradients using submicron pores is discussed.