Flow cell SELEX

A method for identifying a nucleic acid ligand to a target from a candidate mixture of nucleic acids comprising:

• a) immobilizing a target on a sensor chip;
• b) preparing a candidate mixture of nucleic acids;
• c) dividing said candidate mixture into a plurality of aliquots;
• d) passing a first aliquot over the surface of the sensor chip, wherein nucleic acids having increased affinity to the immobilized target relative to the candidate mixture are bound to the immobilized target;
• e) passing a wash buffer over the sensor chip to remove unbound nucleic acids;
• f) repeating steps d) and e) until all of the aliquots have been injected;
• g) passing an eluent over the sensor chip at a determined flow rate to elute the nucleic acids which are bound to the immobilized target;
• and
• h) amplifying the eluted nucleic acids to yield a ligand-enriched mixture of nucleic acids, whereby a nucleic acid ligand to a target is identified.

A method for identifying a nucleic acid ligand to a target from a candidate mixture of nucleic acids comprising:

• a) immobilizing a target on a sensor chip;
• b) preparing a candidate mixture of nucleic acids;
• c) dividing said candidate mixture into a plurality of aliquots;
• d) passing a first aliquot over the surface of the sensor chip in a controlled flow, wherein nucleic acids having increased affinity to the immobilized target relative to the candidate mixture are bound to the immobilized target;
• e) washing the sensor chip with a buffer to remove unbound nucleic acids;
• f) eluting the nucleic acids which are bound to the immobilized target;
• g) repeating steps d), e), and f) until all of the aliquots of the candidate mixture have been injected;
• h) combining the eluted nucleic acids from step f);
• and
• i) amplifying the combined eluted nucleic acids to yield a ligand-enriched mixture of nucleic acids, whereby a nucleic acid ligand to a target molecule is identified.