Abstract: Biospecific desorption microflow systems and methods employing immobilized prebound members of a binding pair are disclosed are used in detecting analytes in samples, identifying binding sites and studying biospecific interactions and their inhibitors on intact cells, cell membranes, cell organelles, cell fragments, proteins, and other biopolymers. The microflow reaction channel is in fluid connection with one or more reservoirs each having a means for transporting fluids or sample to a microflow channel having a prebound binding pair. The biospecifically desorbed labeled molecules may be continuously detected and quantitated on-line. Apparent dissociation constants and 1C50 values (for inhibitors) may be computed automatically. Fluorescent, luminescent, or electrogenic labels may be used to provide continuous flow microsystems having subpicomole sensitivities. Using microfluidic arrays, a single sample may be analyzed for the presence of multiple functional binding sites simultaneously.