If one is clever, one can use SPR to interrogate a surface: monitor the surface and you can “see” the surface changing when stuff is sticking to it. If you have

If one is clever, one can use SPR to interrogate a surface: monitor the surface and you can “see” the surface changing when stuff is sticking to it. If you have something with specific binding properties on that surface, like an antibody (as is used in an ELISA), with some additional effort you can maybe have an assay that detects something binding to that antibody.