Field effect transistor-based sensors

Artigas J, Beltran A, Jimenez C et al (2001) Application of ion selective field effect transistor based sensors to soil analysis. Comp Electron Agric 31(3) 281-293... 

D.S. Kim, H.J. Park, H.M. Jung, J.K. Shin, Y.T. Jeong, P. Choi, J.H. Lee, and G. Lim, Field-effect transistor-based biomolecular sensor employing a Pt reference electrode for the detection of deoxyribonucleic acid sequence. Jpn, J. Appl. Phys. 43, 3855-3859 (2004). 

Gabriel, J. P. 2004. Carbon nanotube field effect transistors and sensors based on nanotube networks. Mater. Res. Soc. Proc., Session HH 14.5. 

Carbon nanotubes, especially SWNTs, with their fascinating electrical properties, dimensional proximity to biomacromolecules (e.g., DNA of 1 nm in size), and high sensitivity to surrounding environments, are ideal components in biosensors not only as electrodes for signal transmission but also as detectors for sensing biomolecules and biospecies. In terms of configuration and detection mechanism, biosensors based on carbon nanotubes may be divided into two categories electrochemical sensors and field effect transistor (FET) sensors. Since a number of recent reviews on the former have been published,6,62,63 our focus here is mostly on FET sensors. 

Electroehemical transdueers are elassified as amperometric, potentiometric or conductometrie [8]. In addition we will here consider field-effect transistor-based transducers separately. Potentiometric sensors make use of the development of an electrical potential at the surface of an electrode when it is placed in a solution containing ions that can exchange with the surface. The potential of the electrode is... 

In this section, the performances of electrical gas sensors based on SWCNTs are reviewed. Three types of gas sensors are introduced field-effect transistor based on individual SWCNT and chemiresistor or field-effect transistor based on SWCNT network. 

Peng, N., Zhang, Q., Lee, Y. C.,Tan, O. K. and Marzari,N. (2008), Gate modulation in carbon nanotube field effect transistors-based NH3 gas sensors . Sensors And Actuators B, 132,191-5. 

It was established that IL-based chemically sensitive field-effect transistors and quartz crystal microbalance sensors can be developed as well (see, e.g.. Fig. 7.4). For example, chemically sensitive field-effect transistors based on a composite of camphorsulfonic acid (CSA)-doped polyaniline (PAN) and an IL of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)-imide, BMI(Tf,N) could... 

Novel glycerol and formaldehyde selective sensors based on pEI-Sensitive Field Effect Transistors as transducers and Glycerol Dehydrogenase and Formaldehyde Dehydrogenase as biorecognition elements have been developed. The main analytical parameters of the sensors have been investigated and will be discussed. 

In recent years further concepts have been developed for the construction of polymer-based diodes, requiring either two conjugated polymers (PA and poly(A-methyl-pyrrole) 2 > or poly(A-methylpyrrole in a p-type silicon wafer solid-state field-effect transistor By modifying the transistor switching, these electronic devices can also be employed as pH-sensitive chemical sensors or as hydrogen or oxygen sensors 221) in aqueous solutions. Recently a PPy alcohol sensor has also been reported 222). 

The ISFET is an electrochemical sensor based on a modification of the metal oxide semiconductor field effect transistor (MOSFET). The metal gate of the MOSFET is replaced by a reference electrode and the gate insulator is exposed to the analyte solution or is coated with an ion-selective membrane as illustrated in Fig. 

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