Open AccessThe effect of nickel ions on structure and conductivity of DNA
Author(s) -
Li Ke,
Dong Rui-Xin,
G. Ban,
Han Hong-wen,
Wei Su,
Xi Yan
Publication year - 2009
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.58.6477
Subject(s) - dna , nickel , ion , conductivity , molecule , raman spectroscopy , materials science , analytical chemistry (journal) , crystallography , chemistry , biochemistry , organic chemistry , physics , optics , metallurgy
The modified M-DNA molecular wires were prepared by adding nickel ions of low concentration to the calf thymus DNA in alkaline solution. And we investigated the conductivity of single DNA and M-DNA molecules. The results indicated that the M-DNA and the B-DNA show semiconductor properties. But the conductivity of M-DNA is higher than that of the B-DNAand the voltage gap is smaller. When the concentration of nickel ions is more than 0.1 m mol/Lthe conductance of DNA does not change with the nickel concentration. In additionthe right to left-handed DNA transition was realized by adding nickel ions of appropriate concentration to the calf thymus DNA in neutral solution and the structure of left handed Z-DNA was observed by STM. The result showed that the major and minor grooves are obviousunwinding and disordering regions can be found in the Z-DNA. The conductivity of left-handed DNA was much lower than that of the B-DNA. The conductivity relationship of B-DNAM-DNA and Z-DNA is GM-DNA>GB-DNA>GZ-DNA. The UV absorption spectra and the Raman spectra indicated that the transition of B-Z DNA appears when the concentration of nickel ions is about 1.7 mol/L.