Antibody-Antigen assay design for combined optical tweezers and fluorescence

Abstract

The recent development in combined optical trapping and fluorescence technology promises to enable unbindinig force studies of receptor-ligand interactions, whose specificity play a crucial role in the function of many biological systems. This thesis focuses on the development of assay designs for the study of antibody-antigen binding interactions using combined optical trapping and single molecule fluorescence. The assays create the necessary linkage geometry between the antibody-antigen system under study to an optically trapped bead, enabling force probing of the antibody-antigen binding interaction. In particular, two tether materials and fluorophores were studied: polyethylene glycol (PEG) with Cy-2, and dsDNA with fluorescein. We demonstrate tether formation in the dsDNA-fluorescein antibody-antigen linkage system with preliminary optical trapping data.