Akademik Veri Yönetim Sistemi
BIOSENSORS & BIOELECTRONICS, cilt.31, sa.1, ss.516-522, 2012 (SCI-Expanded)
An electrochemical genosensor for the detection of hypermethylation of the glutathione S-transferase P1 (GSTP1) gene, a specific marker of prostate cancer, was reported. This new sensor was used in combination with a single-use carbon graphite working electrode and differential pulse voltammetry, with the results of sample analysis based on the guanine oxidation signals obtained at +1.0 V before and after hybridization between probe and synthetic target or denatured PCR samples. The detected DNA hybridization was also characterized by electrochemical impedance spectroscopy with potassium ferri/ferrocyanide as a redox probe. The protocol consisted of 2 different modes: (i) capture probes selective for methylation-specific and unmethylated GSTP1 sequences were immobilized onto the sensor directly, and hybridization was formed on the electrode surface; (ii) probe/target or probe/noncomplementary target couples were mixed in solution phase, and the transducer was modified through simple adsorption. The limit of detection (S/N = 3) was calculated as 2.92 pmol of target sequence in a 100-mu l reaction volume. The optimum analytical detection parameters for the biosensor, as well as its future prospects, were also presented. (C) 2011 Elsevier B.V. All rights reserved.