Immuno field effect transistors

An antibody is an electrically charged protein, and its coupling with an antigen can give rise to variation in the dielectric constant which is measurable with a semiconductor sensor (see 4.6.1). Thus, immuno-FET (or IMFET, immuno-field-effect transistors) are constructed by immobilizing immunoagents on field-effect transistors (FET). 

ImFET immuno-sensing field effect transistor... 

Field-effect Transistors Enzyme FETs and immuno FETs (IMFETs) are based on principles similar to those valid in potentiometric membrane biosensors. The enzyme is immobihzed on top of the ion-selective membrane on the gate of the FET. For construction of ENFETs, usually double-gate FETs are used employing one gate as a reference system, covered only with a layer of the immobilization matrix, and allowing for the real-time compensation of pH modulations, temperature, and drift. Mostly, pH-sensitive FETs (ISFET)... 

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