title: Direct DNA hybridization at disposable graphite electrodes modified with carbon nanotubes.
abstract: The performance of glassy carbon (GCE) and graphite pencil electrodes (PGE) modified with multiwalled carbon nanotubes (CNTs) are compared, based on the direct electrochemical detection of nucleic acids. This is accomplished by monitoring the differential pulse voltammetry changes of the guanine signal. CNT-modified PGE compares favorably to that of the commonly used CNT-modified GCE owing to the intrinsic improved performance of the supporting PGE. The better intrinsic characteristics of the PGE are related to its composite structure and higher level of porosity compared to GCE. The performance characteristics of the direct DNA hybridization on the disposable CNT-modified PGE are studied in terms of optimum analytical conditions such as probe concentration, target concentration, hybridization time, and selectivity. The new DNA biosensor described here has shown some important advantages such being inexpensive, sensitive, selective, and able to generate reproducible results using a simple and direct electrochemical protocol.
authors.affiliation: Analytical Chemistry Department, Faculty of Pharmacy, Ege University, 35100 Bornova, Izmir, Turkey. arzum. erdem@ege.edu.tr
authors.forename: Arzum
authors.initials: A
authors.lastname: Erdem
authors.forename: Pagona
authors.initials: P
authors.lastname: Papakonstantinou
authors.forename: Hayley
authors.initials: H
authors.lastname: Murphy
mesh_terms: D004247:DNA / Q000737:chemistry*; D004566:Electrodes; D006147:Guanine / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009693:Nucleic Acid Hybridization / Q000379:methods*; D011199:Potentiometry / Q000379:methods*; D015203:Reproducibility of Results
chemical_list: D037742:Nanotubes, Carbon; D006147:Guanine; D004247:DNA