WE CLAIM:
1. A method of detecting a nucleic acid, comprising the following steps of:
a) mixing a solution containing a carboxylic acid and/or a salt thereof, a cerium oxide support and a sample containing a nucleic acid to adsorb said nucleic acid to said cerium oxide support,
b) separating said cerium oxide support on which said nucleic acid was adsorbed from the mixture obtained in the step a),
c) collecting said nucleic acid by adding an eluent to said cerium oxide support on which said nucleic acid was adsorbed and which was separated in the step b), and
d) detecting said nucleic acid collected in the step c) by a hybridization reaction or a nucleic acid amplification reaction.
2. A method of detecting a nucleic acid having a higher order structure, comprising the following steps of:
a) mixing a solution containing a carboxylic acid and/or a salt thereof, a cerium oxide support and a sample containing a nucleic acid having a higher order structure to adsorb said nucleic acid to said cerium oxide support,
b) separating said cerium oxide support on which said nucleic acid was adsorbed from the mixture obtained in the step a),
c) collecting said nucleic acid by adding an eluent to the support on which said nucleic acid was adsorbed and which was separated in the step b).
d) detecting said nucleic acid collected in the step c) by a hybridization reaction or a nucleic acid amplification reaction.
3. The method of detecting a nucleic acid according to claim 2, wherein said nucleic acid having a higher order structure has any of the following structures: a higher order structure having a basic structure of a base pair formation other than a base pair formation of A and T (U) pairing and G and C pairing, a higher order
structure having a basic structure of a non-formation of A and T (U) base paring and G and C base paring, and a higher order structure formed as a result of distortion in the double helix structure having a basic structure of a base pair formation of A and T (U), and G and C.
4. The method of detecting a nucleic acid according to claim 2 or 3, wherein said nucleic acid having a higher order structure has any of the following structures: mismatch structure, bulge structure, loop structure, hairpin structure, dangling end structure, pseudoknot structure, branch structure, quadruplex structure, octaplex structure, triplex structure, and circular structure.
5. The method of detecting a nucleic acid according to any one of claims 1 to 4, wherein said carboxylic acid is acetic acid, oxalic acid, citric acid, or ethylenediaminetetraacetic acid (EDTA).
6. The method of detecting a nucleic acid according to any one of claims 1 to 5, wherein said eluent is a buffer solution.