Methods for screening compound libraries

A method for screening at least one target receptor to determine the relative affinity of the at least one receptor to at least one immobilized ligand relative to at least one indicator compound which method comprises:

• (a) providing at least one target receptor each s elected from the group consisting of peptides, proteins, glycoproteins, glycosaminoglycans, proteoglycans, integrins, enzymes, lectins, selectins, cell-adhesion molecules, toxins, transport proteins, hormones, antibodies, cadherins, DNA, DNA fragments, RNA and RNA fragments;
• (b) providing a column comprising at least one ligand, each ligand immobilized on a solid phase support;
• (c) providing at least one void marker compound;
• (d) providing at least one indicator compound for each ligand, each indicator compound having a pre-determined affinity for the ligand and having a pre-determined break through time on the column relative to a void marker compound;
• (e) applying the at least one target receptor to the column under frontal chromatography conditions to partially equilibriate the column with the at least one target receptor;
• (f) applying (i) a mixture comprising the at least one target receptor, the at least one void marker compound and the at least one indicator compound, or (ii) a mixture comprising the at least one void marker compound and the at least one indicator compound, to the column under frontal chromatography conditions to provide an effluent;
• (g) analyzing the effluent to determine a break through time for the at least one indicator compounds;
• and
• (h) determining whether any of the at least one target receptor has an affinity for the at least one ligand as measured by the at least one indicator compound by comparing the break through time for the at least one indicator compound from step (g) with the pre-determined break through time for the at least one indicator compound.