The i nteraction among Co(phen) 33+ ,6-Mercaptopurine(6-MP)and calf thymus DNA has been investigated us-ing c yclic voltammetry,differential pulse voltammetry and UV-spectra in Tris buffer solutions(pH=7.2).In the pre...The i nteraction among Co(phen) 33+ ,6-Mercaptopurine(6-MP)and calf thymus DNA has been investigated us-ing c yclic voltammetry,differential pulse voltammetry and UV-spectra in Tris buffer solutions(pH=7.2).In the presence of6-MP,the redox peak current at0.15V for the central cobalt ion from voltammograms is significantly reduced compared with th at in the absence of6-MP and the current of a new quasi-reversible redox wave shown at-0.06V gradually increases with6-MP addition.However,when DNA is furthe r added,the peak current at0.15V is renewedly enlarged and the redox at-0.06V gr adually disappears with DNA addition.At the same time,UV-spectra of Co(phen) 33+ are regularly changed in the presence of6-MP and DNA.All results indicate t hat the obvious interaction equilibrium is proved to exist among Co(phen) 33+ ,6-MP and calf thymus DNA.展开更多
The binding mode of Eu(phen)_3^(3+) with DNA is studied by fluorescence andvoltammetric methods. From the Scatchard graph and the fluorescence quenching phenomenon, it isconcluded that the mode of interaction between ...The binding mode of Eu(phen)_3^(3+) with DNA is studied by fluorescence andvoltammetric methods. From the Scatchard graph and the fluorescence quenching phenomenon, it isconcluded that the mode of interaction between Eu(phen)_3^(3+) and DNA is intercalation bind byinserting the phen pi-pi conjugate surface between the base pairs of the DNA duplex. Voltammetry wasused to confirm the results obtained from the fluorescence method, the result from both methodsagrees with each other. The binding constant (K) and the binding site size (n_s) were calculatedfrom voltammetric data such as the shifts in potential and limiting currents in the process ofadding DNA, according to the positive shifts of peak potential. It was considered that the complexof the +2 ion interacted more favorably with the nucleotide bases than that of the +3 ion byhydrophobic interaction.展开更多
文摘The i nteraction among Co(phen) 33+ ,6-Mercaptopurine(6-MP)and calf thymus DNA has been investigated us-ing c yclic voltammetry,differential pulse voltammetry and UV-spectra in Tris buffer solutions(pH=7.2).In the presence of6-MP,the redox peak current at0.15V for the central cobalt ion from voltammograms is significantly reduced compared with th at in the absence of6-MP and the current of a new quasi-reversible redox wave shown at-0.06V gradually increases with6-MP addition.However,when DNA is furthe r added,the peak current at0.15V is renewedly enlarged and the redox at-0.06V gr adually disappears with DNA addition.At the same time,UV-spectra of Co(phen) 33+ are regularly changed in the presence of6-MP and DNA.All results indicate t hat the obvious interaction equilibrium is proved to exist among Co(phen) 33+ ,6-MP and calf thymus DNA.
基金This project is financially supported by the Natural Foundation of Gansu Province (GZ 97-0025) NWNUKJCXGC-01(No. 001)
文摘The binding mode of Eu(phen)_3^(3+) with DNA is studied by fluorescence andvoltammetric methods. From the Scatchard graph and the fluorescence quenching phenomenon, it isconcluded that the mode of interaction between Eu(phen)_3^(3+) and DNA is intercalation bind byinserting the phen pi-pi conjugate surface between the base pairs of the DNA duplex. Voltammetry wasused to confirm the results obtained from the fluorescence method, the result from both methodsagrees with each other. The binding constant (K) and the binding site size (n_s) were calculatedfrom voltammetric data such as the shifts in potential and limiting currents in the process ofadding DNA, according to the positive shifts of peak potential. It was considered that the complexof the +2 ion interacted more favorably with the nucleotide bases than that of the +3 ion byhydrophobic interaction.
