METHODS FOR GENERATING APTAMERS WITH IMPROVED OFF-RATES

摘要

PROBLEM TO BE SOLVED: To provide aptamers having improved properties, photoaptamers and preparation methods thereof.SOLUTION: A method for identifying an aptamer having slow dissociation rate from the target molecule and comprising at least one base-modified pyrimidine is provided, which method comprises the steps of: contacting a target molecule and a candidate mixture comprising modified nucleic acids of which one or plural or all pyrimidine residues are chemically modified at position 5 to generate base-modified pyrimidines; forming a complex of the target molecule and a nucleic acid having an increased affinity to the target molecule in relation to other nucleic acids in the candidate mixture; separating nucleic acid-target molecule complexes from the candidate mixture; dissociating the nucleic acid-target molecule complexes to generate free nucleic acids which are amplified to obtain a nucleic acid mixture in which sequences capable of binding to the target molecule with increased affinity are enriched; and repeating these steps as necessary.SELECTED DRAWING: None