Surface plasmon resonance biosensor based on grating disc with circular fluidic channel

We presented a grating-coupled surface plasmon resonance (SPR) biosensor with a circular fluidic channel on a grating disc. Test solution can be moved forward in the fluidic channel by gravity through turning the grating disc. It can react with the probe molecules on the different sensing surfaces in the following the sequential time. In order to identify the angle changes of SPR due to the molecular interaction, a protein of bovine serum albumin (BSA) is employed as a target to be immobilized on the sensing surfaces. The measured response curve showed that the saturation time of the immobilized reaction is about 15 minutes when 0.1 mg/ml BSA reacted with a NHS-ester-terminated self-assembled monolayer (SAM) at room temperature. If a proper-designed chamber for sample stocking is assembled on grating disc, the disc-like biosensor can be applied for a kinetics analysis of bimolecular interaction without any fluid pumping systems.