The effect of temperature on electrochemically driven denaturation monitored by SERS

Scanning the electrochemical potential negative results in the gradual denaturation of dsDNA immobilised at a nanostructure gold electrode, the DNA melting is monitored by SERS. We demonstrate the effect of the experimental temperature on the electrochemically driven melting (E-melting) by carrying out experiments between 10 and 28 degrees C using two DNA duplexes (20 and 21 base pairs). Significant temperature dependence for both the melting potentials, Em, and the steepness of the melting curves was found over the range 10 to 18 degrees C Above 18 degrees C the results were found to be independent of temperature. The relative temperature insensitivity of the melting potentials above 18 degrees C is advantageous for the application of the electrochemically driven melting technique because precise temperature control is not necessary for measurements that are carried out around room temperature. Conversely temperature dependence below 18 degrees C offers a way to improve discrimination for highly similar DNA sequences. (C) 2015 Elsevier B.V. All rights reserved.