Patent ID: 7972792

Claim:
A method of purifying a target nucleic acid having a particular base sequence that is contained in a nucleic acid mixture, the method comprising: hybridizing a photo-ligating nucleic acid (wherein the nucleic acid includes a nucleic acid and a peptide nucleic acid) having a group represented by the following formula (I) as a base moiety: (wherein in the formula (I), Ra represents a cyano group, an amide group, a carboxyl group, a C2-C7 alkoxycarbonyl group or hydrogen; and R1 and R2 each independently represent a cyano group, an amide group, a carboxyl group, a C2-C7 alkoxycarbonyl group or hydrogen), with the target nucleic acid having a particular base sequence that is contained in a nucleic acid mixture; irradiating the hybrid of the photo-ligating nucleic acid and target nucleic acid with light to induce photo-ligation of the hybrid; removing any un-photo-ligated nucleic acid by washing; and irradiating the hybrid of the photo-ligating nucleic acid and the target nucleic acid with light to induce photo-cleavage of the hybrid.