Surface Plasmon Resonance Multisensing

We have demonstrated the feasibility of surface plasmon resonance (SPR) multisensing by monitoring four separate immunoreactions simultaneously in real time using a multichannel SPR instrument. A plasmon carrying gold layer, onto which a four-channel flow cell was pressed, was imaged at a fixed angle of incidence. First, the four-channels were coated with antibodies and then the flow cell was turned by 90° such that the flow channels overlapped the areas coated in the first step. In that geometry, antigens were applied to the different antibodies on the surface. Thus, all antibody−antigen combinations can be measured in a two-dimensional array of sensor surfaces in real time. Our results do correlate with expected immunologic specificity. The emphasis will be on presenting this method to obtain data on immunosystems and not as much on the assessment of biological activity.