INTEGRATED DIFFERENCE ENFETs

Enzyme field effect transistors (ENFETS) were assembled by immobilizing enzymes to a multigate proton and fluoride ion sensitive field effect transistor. Two variations of difference mode measurements of glucose have been realized. All the gates and electrodes at the chip have been homogeneously covererd by a crosslinked, enzyme containing Polyurethane matrix. The difference of the output voltages of a PH-ENFET and a pF reference FET (REFET) or the difference of a pF-ENFET and a pHREFET are measured using an integrated thin film noble metal electrode as pseudo-reference