Detection of Abasic Sites in DNA by Electrochemical, Immunoelectrochemical and Acoustic Methods Using OsO4, 2,2′-bipyridine as a Probe for Unpaired Thymine Residues

We report on comparative analysis of the detection of DNA damage modeled by presence of abasic sites (AP) at defined positions using the chemical modification of the DNA by the complex of osmium tetroxide-2,2-bipyridine (Os, bipy) that selectively binds to unpaired thymine residues in the damaged DNA. AP were detected by electrochemical detection (EC) of the Os, bipy-thymine adducts, by immunoelectrochemical (IE) and by thickness shear mode acoustic methods (TSM). EC method of detection can perfectly distinguish between the number of A P. I E and TSM methods were of comparable sensitivity.