Amplifying the electrical hybridization signals of DNA array by multilayer assembly of Au nanoparticle probes.
This paper describes a versatile method for amplifying the signals of Au-nanoparticle-based DNA hybridization detecting systems. The Au nanoparticles usually serve as labels to enhance DNA hybridization signal. We further assembled several layers of nanoparticles to selectively increase the number of labelled nanoparticles. Through silver enhancement, the multilayer nanoparticles may produce significantly higher amounts of metal silver on the their surfaces than the monolayer nanoparticles did. This finally accounts for the greatly enhanced DNA hybridization signal. Particularly, the amplification of electrical detection system was demonstrated here. Electrical measuring results indicated that the current values were enhanced by approximately 3 orders of magnitude, and the single nucleotide mismatch discrimination ratio was enlarged to approximately 10(9):1.
Li
Jiong
J
Department of Electrical and Electronic Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
Xue
Mei
M
Wang
Hong
H
Cheng
Lu
L
Gao
Lu
L
Lu
Zuhong
Z
Chan
Mansun
M
D000818:Animals; D004247:DNA / Q000032:analysis*; D004563:Electrochemistry / Q000379:methods; D006046:Gold; D036103:Nanotechnology / Q000379:methods; D009693:Nucleic Acid Hybridization / Q000379:methods; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*
D006046:Gold; D004247:DNA