Field Effect Biosensing (FEB) is a breakthrough label-free technology for measuring biomolecular interactions

FEB Technology

For the first time, scientists have direct visibility into the electrical signaling that natively occurs in biological systems without intermediary translations from optical data. At the heart of Agile R100 is a graphene biosensor chip built with proprietary Field Effect Biosensing (FEB) technology. FEB, an electrical technique, measures the current across a field effect graphene biosensor to which targets are immobilized (Figure 1). Any interaction or binding that occurs on the surface causes a change in conductance that is monitored in real-time (Figure 2), enabling accurate kinetic, affinity, and concentration measurements.

Field Effect Biosensing (FEB) technology image

Only molecules binding to or dissociating from the biosensor surface cause a change in conductance on the Agile platform. Unbound molecules, crude media or solvents that might interfere with optics, or changes in flow rate do not affect the conductance reading. This distinctive feature enables detection in complex samples such as DMSO, cell and tissue lysate, and blood fractions, making FEB an efficient technology for small molecule or fragment-based drug discovery and antibody characterization.

Small Molecule Detection with an FEB system

FEB is fundamentally different from optical techniques such as SPR or BLI. Optical systems measure shifts in light caused by changes in mass, which is effective for large molecules. SPR and BLI struggle to measure interactions <1000 Da without solvent correction and additional calculations.

In contrast, FEB is an electrical technique, not a mass-based method. The size of the molecule does not impact the change in conductance experienced when an interaction occurs, enabling sensitive detection of biomolecules >1 Da. This makes FEB an excellent orthogonal technique for small molecule and fragment characterization and validation.

No microfluidics - no clogging or set association phasecheckcheckno
Single step reading - fast response, less timecheckcheckno
No impacts due to change in refractive index of surrounding mediumcheckcheckno
No need for solvent correction – reduce number of measurementschecknono
Ability to detect >1 Dachecknono
Portable - low weight, small sizechecknono