Patent ID: 8119347

Claim:
A method for detecting an anionic G-quadruplex in a sample solution comprising an anionic DNA forming at least any one or more structures of an anionic single stranded structure, an anionic double stranded structure and an anionic G-quadruplex structure, the method comprising the steps of: (a) preparing a solution comprising an anionic planar phthalocyanine; (b) mixing the solution comprising an anionic planar phthalocyanine with the sample solution; (c) measuring the absorbance at 640 to 740 nm of a liquid mixture obtained following the step (b); and (d) determining that an anionic DNA forming an anionic G-quadruplex structure is included in the sample solution when a peak having an absorption maximum at 640 to 740 nm appears, in this order.