Method of selecting aptamers

A method for the identification of at least one aptamer to at least one target molecule, the method comprising:

• a) contacting a pool of candidate aptamer sequences with the at least one target molecule;
• b) partitioning unbound sequences from those sequences that have bound specifically to the at least one target molecule;
• c) dissociating the sequence-target complexes to obtain a ligand-enriched mixture of sequences;
• d) assigning to each sequence obtained in step c) a measure of the sequence's potential as an aptamer, wherein the measure comprises a fitness function;
• e) using the measure of step d) to determine the aptameric potential of the ligand-enriched mixture;
• f) allowing evolution of some or all of the sequences obtained in step c) using information obtained in step e) to create a new candidate aptamer pool;
• and
• g) repeating the steps a) to f) using the new candidate aptamer pool created in step f) as the input pool of candidate aptamer sequences in the next iteration of step a) until the aggregate aptameric potential of the candidate pool reaches a plateau, wherein sequences present in the final candidate aptamer pool are optimal aptamers to the at least one target molecule, thereby identifying the at least one aptamer.