Published In

Nucleic Acids Research

Document Type

Article

Publication Date

2008

Subjects

Thermodynamics, Nucleic acid probes, DNA

Abstract

The temperature induced melting transition of a self-complementary DNA strand covalently attached at the 5' end to the surface of a gold interdigitated microelectrode (GIME) was monitored in a novel, label-free, manner. The structural state of the hairpin was assessed by measuring four different electronic properties of the GIME (capacitance, impedance, dissipation factor and phase angle) as a function of temperature from 25 degrees C to 80 degrees C. Consistent changes in all four electronic properties of the GIME were observed over this temperature range, and attributed to the transition of the attached single-stranded DNA (ssDNA) from an intramolecular, folded hairpin structure to a melted ssDNA. The melting curve of the self-complementary single strand was also measured in solution using differential scanning calorimetry (DSC) and UV absorbance spectroscopy. Temperature dependent electronic measurements on the surface and absorbance versus temperature values measured in solution experiments were analyzed assuming a two-state process. The model analysis provided estimates of the thermodynamic transition parameters of the hairpin on the surface. Two-state analyses of optical melting data and DSC measurements provided evaluations of the thermodynamic transition parameters of the hairpin in solution. Comparison of surface and solution measurements provided quantitative evaluation of the effect of the surface on the thermodynamics of the melting transition of the DNA hairpin.

Description

This is the publisher's final PDF. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

DOI

10.1093/nar/gkn436

Persistent Identifier

http://archives.pdx.edu/ds/psu/11088

Share

COinS