Methoxyphenol and Dihydrobenzofuran as Oxidizable Labels for Electrochemical Detection of DNA
4-Hydroxy-3-methoxyphenyl (MOP) and 2,3-dihydrobenzofuran-5-yl (DHB) groups were tested as potential new oxidizable labels for electrochemical detection of DNA. The corresponding 5-aryl-cytosine and 7-aryl-7-deazaadenine 2-deoxyribonucleoside triphosphates (dNTPs) were prepared by the Suzuki coupling of halogenated dNTPs or by triphosphorylation of modified nucleosides, and were incorporated enzymatically into DNA by polymerase. In parallel, the electrochemical behavior of the labeled nucleosides, nucleotides, and DNA was studied to show that most of them give analytically useful signals of oxidation on the carbon electrode. Particularly, MOP appears to be a useful oxidizable DNA label since it offers independent detection of the modified DNA.