Amperometric Detection of dsDNA via Acrydinium Orange Modified Glucose Oxidase

In the present "genomic era" and developing world of DNA chips DNA detection based on intercalation of specific molecules is of particular interest because the detection process is largely indepen-dent of the sequence of the target DNA. In this work, an acridine orange based intercalator, which was tethered to deglycosylated glucose oxidase was ad-hoc synthesized and investigated towards its ability for the interaction with dsDNA. Amperometric detection of the DNA hybridization was done by signal amplification based on the catalytic oxidation of glucose by DNA-bound glucose oxidase. A clear distinction between dsDNA and ssDNA was achieved owing to a carefully designed DNA-modified electrode surface and prevention of unspecific adsorption of the acridinium orange modified enzyme by implementing a potential-assisted immobilization method for the fabri¬cation of DNA sensing platforms.