Electrochemical DNA sensing based on gold nanoparticle amplification.
A hybridization signal-amplified method based on a gold nanoparticle-supported DNA sequence for electrochemical DNA sensing has been investigated by cyclic voltammetry, differential-pulse voltammetry, and atomic-force microscopy (AFM). Quantitative analysis showed that the peak current increment (DeltaIp) is linearly dependent on the concentration of the gold nanoparticle-supported DNA sequence Au2 over the range 0.51-8.58 pmol L(-1). AFM results indicated that the extent of surface hybridization was dependent on the concentration of the gold-nanoparticle-supported DNA sequence. Moreover, a new pair of peaks, which might arise from the special configuration of the gold-nanoparticle-supported DNA sequence, appeared in the cyclic voltammogram after hybridization. Although quite sensitive, this DNA sensing surface was not easily regenerated, so this kind of amplified method was suitable for disposable DNA sensors and chip-based gene diagnosis sensors.
Zhang
Zhi-Ling
ZL
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, P. R. China.
Pang
Dai-Wen
DW
Yuan
Hong
H
Cai
Ru-Xiu
RX
Abruña
Héctor D
HD
D001483:Base Sequence; D015342:DNA Probes; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D036103:Nanotechnology; D010316:Particle Size
D015342:DNA Probes; D006046:Gold