How does Field Effect Biosensing (FEB) work?

 

Field Effect Biosensing is a breakthrough label-free technology for measuring biomolecular interactions, and it’s different from anything you’ve heard of before. It is an electrical technique that measures the current across a graphene biosensor surface functionalized with immobilized biomolecular targets (Figure 1). Any interaction or binding that occurs on the surface causes a change in conductance of the biosensor (Figure 2) that is monitoring binding confirmation in real-time. FEB is a unique orthogonal technology that works when optical methods fail, and it can only be found with innovative graphene biosensor Agile R100.

Field Effect Biosensing (FEB) technology image

Small Molecule Detection with an FEB system

The FEB method on which Agile R100 is based is fundamentally different from optical techniques. Optical tools such as SPR and BLI systems measure mass-dependent shifts in light, which is adequate for large molecules. However, SPR and BLI platforms struggle to measure small molecule interactions because small molecules elicit correspondingly small sensor responses. To find the needle of signal generated in a large haystack of background noise, time-consuming and error-prone solvent correction is required.

In contrast, FEB is a completely orthogonal, breakthrough technology. It is an electrical technique, not an optical, mass-based method. The size of the molecule being measured is irrelevant on an FEB platform because molecule size doesn’t impact what FEB measures: the change in biosensor conductance caused by a binding interaction at its surface. In fact, small molecules generally create optimal effects on an FEB platform because small molecules have large chemical potential shifts in relation to their volume, which produces a large response with FEB. This makes FEB an excellent orthogonal technique for small molecule and fragment characterization and validation.