Utilization of an osmium complex as a sequence recognizing material for DNA-immobilized electrochemical sensor

A novel immobilized DNA electrode based on a porous carbon electrode was prepared to study interactions between DNA and chemical compounds. The characteristics of this electrode were evaluated by electrochemical methods, and then the interaction between DNA and an osmium complex was studied. On this electrode (electrode surface; 0.66–2.37 cm2), DNA was immobilized at 0.26 × 10−4 − 1.23 × 10−4 mol cm−2. Hybridization of DNA was observed with a relative standard deviation of 11% (n = 4). The tris(bipyridyl)osmium(II/III) ion (osmium complex) was found to interact to major or minor grooves. Using this osmium complex, a DNA sequence could be recognized with more than 12 mer of the same sequence.