Synthesis, Electrochemical Characteristics of [Ni(phen)(H2O)4]SO4⋅2H2O and Its Interaction Mechanism with DNA

A polypyridyl nickel complex of [Ni(phen)(H 2 O) 4 ]SO 4 ⋅2H 2 O (phen = 1,10-phenanthroline) was synthesized and characterized by X-ray diffraction and IR spectroscopy. The results indicated that the central nickel ion is in a distorted octahedral geometry coordinated by two nitrogen atoms from 1,10-phenanthroline and four water molecules. The crystal data for this complex are: a =8.8797(18) Å, b =18.468(4) Å, c =22.081(4) Å, α =90°, β =90°, γ =90°, R 1 =0.0533, and wR 2 =0.2095. Electrochemical experiments showed that the complex could be reoxidized at a gold electrode under the precondition of electrolysis stripping. According to the results of cyclic voltammetry and coulometry, an electrochemical reaction mechanism was proposed. The DNA binding properties of the complex were further investigated by electronic absorption spectrophotometry and electrochemistry. The binding constant and the binding mode between the two species were estimated based on the spectroscopic and electrochemical results.