Real time binding analysis of antigens on a biosensor surface

1. A method for detecting if different epitope classes of antibodies in an antibody population are present as compared to display phage, antibodies, or antibody fragments immobilized on a biosensor comprising:

(a) immobilizing display phage, antibodies, or antibody fragments to a biosensor;

(b) contacting the biosensor with a binding partner that specifically binds to the display phage, antibodies, or antibody fragments immobilized to the biosensor, under conditions suitable for binding of the binding partner to the display phage, antibodies, or antibody fragments;

(c) contacting the antibody population with the biosensor; wherein, a detectable signal generated by binding of the antibody population to the binding partner indicates that different epitope classes are present in the antibody population than in the immobilized display phage, antibodies, or antibody fragments.

2. The method of claim 1 , wherein the antibody population comprises phage clones.

3. The method of claim 1 , wherein the antibody population comprises antibody fragments, full antibodies, phage displaying a full antibody, or phage displaying an antibody fragment.

4. The method of claim 1 , wherein the antibody population comprises antibodies from a hybridoma.

5. The method of claim 1 , wherein the antibody population comprises antibodies from a phage display screen.

6. The method of claim 1 , wherein the display phage is a crude phage preparation, an unconcentrated phage preparation, a concentrated phage preparation or a non-homologous phage preparation.

7. The method of claim 1 , wherein the binding partner is a small molecule, a carbohydrate, a polymer, a peptide, a soluble protein, a cellular receptor, an antigen mimic of a cellular receptor, a mammalian cell, or a mammalian cell surface protein.

8. The method of claim 7 , wherein the mammalian cell surface protein is a membrane-associated protein, a single transmembrane protein, a multi-transmembrane protein, or a protein channel.

9. The method of claim 1 , wherein the biosensor is a colorimetric resonant reflectance biosensor or an evanescent wave-based biosensor.

10. The method of claim 1 , wherein the antibody population, binding partner and immobilized display phage, immobilized antibody, or immobilized antibody fragment do not comprise a detectable label.

11. The method of claim 1 , wherein the display phage, antibodies, or antibody fragments are immobilized in an array format on the biosensor.

12. The method of claim 1 , wherein the biosensor is incorporated into a bottom surface of a microtiter plate comprising wells, and wherein the display phage, antibodies, or antibody fragments are immobilized to the biosensor within each well.

13. The method of claim 1 , where the method further comprises determining the quantity of binding partner bound to the phage immobilized on the biosensor.

14. The method of claim 1 , wherein the biosensor is coated with streptavidin, amines, aldehydes or gluteraldehydes prior to the immobilization of the display phage, antibodies, or antibody fragments to the biosensor.