Effect of Probe Density and Hybridization Temperature on the Response of an Electrochemical Hairpin-DNA Sensor
- 12 November 2008
- journal article
- research article
- Published by American Chemical Society (ACS) in Analytical Chemistry
- Vol. 80 (24) , 9460-9466
Abstract
Detection of specific sequences of target DNA is of high importance in many fields, especially in medicinal diagnostics. This study focuses on the response of an electrochemical, label-free DNA sensor at two different hybridization temperatures (37 and 44 °C). The stem-loop structured probes and the blocking polyethylene glycol molecules were self-assembled on the electrode through S−Au bonding, to form a mixed monolayer employed as the sensing platform. Impedance spectroscopy was used for investigation of the electron transfer processes at a modified gold electrode before and after hybridization with the target DNA. The sensor showed sensitive and selective detection of the target DNA at the lower temperature, whereas the higher temperature affected the dynamics of the hairpin significantly, reflected in an increased sensitivity of the sensor.Keywords
This publication has 30 references indexed in Scilit:
- Sequence-Specific Detection of Femtomolar DNA via a Chronocoulometric DNA Sensor (CDS): Effects of Nanoparticle-Mediated Amplification and Nanoscale Control of DNA Assembly at ElectrodesJournal of the American Chemical Society, 2006
- Impedance-Based DNA Biosensor Employing Molecular Beacon DNA as Probe and Thionine as Charge NeutralizerElectroanalysis, 2006
- Reagentless, Reusable, Ultrasensitive Electrochemical Molecular Beacon AptasensorJournal of the American Chemical Society, 2005
- Towards single-spot multianalyte molecular beacon biosensorsTalanta, 2005
- Sensitivity and Specificity of Metal Surface-Immobilized “Molecular Beacon” BiosensorsJournal of the American Chemical Society, 2005
- Chemical Control of Electrode Functionalization for Detection of DNA Hybridization by Electrochemical Impedance SpectroscopyLangmuir, 2005
- Hybridization-Based Unquenching of DNA Hairpins on Au Surfaces: Prototypical “Molecular Beacon” BiosensorsJournal of the American Chemical Society, 2003
- Single-mismatch detection using gold-quenched fluorescent oligonucleotidesNature Biotechnology, 2001
- Electrochemical Quantitation of DNA Immobilized on GoldAnalytical Chemistry, 1998
- Molecular Beacons: Probes that Fluoresce upon HybridizationNature Biotechnology, 1996