CNTs for Electrochemical DNA Sensing

Baker et al. [95] were the first to report the formation of DNA-SWCNT adducts in solution for DNA hybridization. The DNA-SWCNT complexes were synthesized by reacting oxidized SWCNTs with thionyl chloride and ethylenediamine to form amine-terminated sites, shown in Fig. 14.16. The amines were further reacted with succinimidyl 4-(Af-maleimidomethyl)cyclohexane-l-carboxylate (SMCC) forming maleimide groups which reacted with thiol-modified DNA. To confirm covalent attachment and to test the accessibility of the DNA-modified SWNTs, hybridization studies were conducted using fluorescently labeled DNA oligonucleotide targets. Shortly thereafter, the use of carbodiimide-assisted coupling 

He and Dai [86a] prepared aligned SWCNT-DNA sensors by chemically coupling ssDNA probes on both the tip and wall of plasma-activated aligned carbon nanotubes on gold electrodes. 

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Martinez-Paredes, M. G. Gonzalez-Garcia, and A. Costa-Garcia, Electroanalysis 21, 379-385 (2008J. 

and K Jiao, Anal. Chim. Acta 616, 155-151 [2008], 

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