Electrochemical detection of enzyme labeled DNA based on disposable pencil graphite electrode.
Electrochemical biosensor for the detection of DNA hybridization using the reduction signal of alpha-naphthol is described. A pencil graphite electrode was used as a working electrode. Capture probes were covalently attached on to the pencil graphite electrode surface (PGE) at the 5' end amino group by using N-(dimethylamino)propyl-N'-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysulfosuccinimide (NHS) as a coupling agent on to PGE. After capture probe immobilization on to PGE surface; probe was hybridized with complementary biotinylated oligonucleotide. Alkaline phosphatase labeled with extravidin (Ex-AP) binds to biotinylated hybrid via biotin-avidin interaction. alpha-Naphthyl phosphate (alpha-NAP) was added and the reaction between alkaline phosphatase (AP) and alpha-NAP was occurred consequently as a substrate of AP, alpha-NAP reduction signal was obtained from this reaction, at -0.100 V by using differential pulse voltammetry (DPV). Other experimental parameters were studied such as; optimizations of hybridization time, and the concentrations of capture probe, biotinylated oligonucleotide and enzyme.
Kara
Pinar
P
Analytical Chemistry Department, Faculty of Pharmacy, Ege University, 35100 Bornova-Izmir, Turkey.
Erdem
Arzum
A
Girousi
Stella
S
Ozsoz
Mehmet
M
D000469:Alkaline Phosphatase / Q000737:chemistry*; D001483:Base Sequence; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D017931:DNA Primers; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D006108:Graphite
D017931:DNA Primers; D006108:Graphite; D004247:DNA; D000469:Alkaline Phosphatase