Third-Generation Direct Electron Transfer (DET)

Third-Generation Direct Electron Transfer (DET) sensors represent the theoretical apex of enzymatic glucose sensing, eliminating the need for both oxygen (1st Gen) and artificial mediators (2nd Gen). In DET systems, electrons tunnel directly from the enzyme's redox center (e.g., FAD) to the electrode.

Because the active sites of enzymes like Glucose Oxidase are buried within insulating protein shells, DET requires nanotechnology (Carbon Nanotubes, Gold Nanoparticles) to bridge the gap and facilitate electron tunneling over distances less than 2 nanometers.

The primary advantages of DET include superior selectivity and operation at very low voltages, which eliminates interference from common blood compounds like acetaminophen. However, mass adoption in test strips is hindered by low current density (weak signals) and the high cost of manufacturing nanostructured electrodes compared to standard screen-printed mediator strips.