In:
Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 58, No. 9 ( 2009), p. 6477-
Abstract:
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-DNA，and the voltage gap is smaller. When the concentration of nickel ions is more than 0.1 m mol/L，the conductance of DNA does not change with the nickel concentration. In addition，the 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 obvious，unwinding 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-DNA，M-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.
Type of Medium:
Online Resource
ISSN:
1000-3290
,
1000-3290
Language:
Unknown
Publisher:
Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
Publication Date:
2009
