Label-free detection of DNA molecules on the dendron based self-assembled monolayer by electrochemical impedance spectroscopy.
We report preparation of a novel platform for effective DNA hybridization and its application to the detection of single mismatched DNA. Cone-shaped dendrimer molecules have been immobilized on the gold surface at equidistance, 3.1 nm, from each other with a probe DNA molecule attached to the top of each dendrimer so that enough space would be secured for effective hybridization. This arrangement allows each probe DNA molecule to form a natural DNA double helix upon hybridization with a target DNA molecule. The single nucleotide polymorphism at either the central or end position of the 25-mer target DNA has been shown to be effectively discriminated against on this platform from each other as well as from a complementary DNA by electrochemical impedance measurements. We also report adverse effects exerted by probe ions, Fe(CN)(6)(3-/4-), on DNA hybridization reactions. The significance of the results for the use in DNA analysis is discussed.
Department of Chemistry and Center for Integrated Molecular Systems, Pohang University of Science and Technology, Pohang, Gyeongbuk 790-784, South Korea.
Jin-Young
JY
Park
Sung Hong
SH
Kwon
Joon Won
JW
Park
Su-Moon
SM
Park
D000873:Anthracenes / Q000737:chemistry*; D003486:Cyanides / Q000737:chemistry; D004247:DNA / Q000032:analysis* / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000032:analysis / Q000737:chemistry; D017097:Electric Impedance; D004563:Electrochemistry; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000379:methods*; D013194:Staining and Labeling; D013438:Sulfhydryl Compounds / Q000737:chemistry
D000873:Anthracenes; D003486:Cyanides; D004277:DNA, Single-Stranded; D013438:Sulfhydryl Compounds; C501244:dendron; D004247:DNA