Reactivity of oxanine: efficient fabrication of DNA microarray by using oxanine-containing DNA oligomer as probe molecule.

Oxanine (Oxa), a mutagenic lesion generated from guanine by nitrosative oxidation, can make a covalent bonding with -NH(2) or -SH group since Oxa possesses O-acylisourea conformation in the base-ring structure. We employed such unique reactive functionality of Oxa for fabrication of DNA-immobilized system. When DNA oligomer with Oxa at 5'-end (Oxa-end DNA) is spotted on amine-functionalized surface, the DNA probe can be immobilized without any involvement of activation step or any treatment of chemical linker. We further optimized the fabrication conditions for efficient immobilization of Oxa-end DNA.