The DNA hybridization assay using single-walled carbon nanotubes as ultrasensitive, long-term optical labels.
Single walled carbon nanotubes (SWNTs) exhibit strong Raman signals as well as fluorescence emissions in the near infrared region. Such signals do not blink or photobleach under prolonged excitation, which is an advantage in optical nano-biomarker applications. In this paper, we present single-stranded DNA conjugated SWNT probes to locate a particular sequence of DNA within a complex genome. Chromosomal DNAs of human fibroblasts and Escherichia coli are used as a target and a control, respectively. Southern blotting, which uses photostable Raman signals of nanotubes instead of fluorescent dyes, demonstrates excellent sensitivity and specificity of the probes. The results show that SWNTs may be used as generic nano-biomarkers for the precise detection of specific kinds of genes.
Hwang
Eung-Soo
ES
Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, 110-799, Korea.
Cao
Chengfan
C
Hong
Sanghyun
S
Jung
Hye-Jin
HJ
Cha
Chang-Yong
CY
Choi
Jae-Boong
JB
Kim
Young-Jin
YJ
Baik
Seunghyun
S