Electrochemical impedance spectroscopy and surface plasmon resonance studies of DNA hybridization on gold/SiOx interfaces.
The use of Au/SiO(x) interfaces for the investigation of DNA hybridization using electrochemical impedance spectroscopy (EIS) and surface plasmon resonance (SPR) simultaneously is demonstrated. Standard glass chemistry was used to link single-stranded DNA (ss-DNA) on aldehyde-terminated Au/SiO(x) interfaces. The layer thickness and amount of grafted oligonucleotides (ODNs) were calculated from SPR on the basis of a multilayer system of glass/Ti/Au/SiO(x)/grafted molecule. Capacitance and resistance values of the modified interface before and after hybridization were calculated from EIS data using an equivalent circuit and allowed the affinity rate constant, K(A) = 4.07 x 10(5) M(-1), to be determined. The EIS results were comparable to those obtained by SPR hybridization kinetics recorded in parallel.
Manesse
Maël
M
Laboratoire d'Electrochimie et de Physicochimie des Matériaux et des Interfaces (LEPMI), CNRS-INPG-UJF, 1130 rue de la piscine, BP 75, 38402 St. Martin d'Hères Cedex, France.
Stambouli
Valerie
V
Boukherroub
Rabah
R
Szunerits
Sabine
S
D004247:DNA / Q000032:analysis*; D017097:Electric Impedance; D004566:Electrodes; D006046:Gold; D017403:In Situ Hybridization; D012822:Silicon Dioxide; D013057:Spectrum Analysis / Q000379:methods; D020349:Surface Plasmon Resonance
D006046:Gold; D012822:Silicon Dioxide; D004247:DNA