Durable nitrate-selective chemically modified field effect transistors based on new polysiloxane membranes

Anion Sensors

“…CHEMFETs containing this receptor showed a 300-fold selectivity for fluoride over nitrate, bromide, and chloride [21]. Other modified CHEMFETs show selectivity for nitrate [22] and dihydrogen phosphate [23]. Optodes are devices that also employ selective membranes to sense guests, but unlike ISEs, which measure changes in potential, optodes function by detecting changes in the optical properties of the membrane.…”

Photocurable Polymers for Ion Selective Field Effect Transistors. 20 Years of Applications

“…Attempts to prevent the leaching of ion active components from thin (30–100 μm) membranes began with the synthesis of a so called copolymerisable plasticizer [ 62 ]. More lately “plasticizer-free” [ 36 , 37 ] or “self-plasticizing” [ 38 , 39 ] ion-selective membranes have been introduced. This work was performed by the group from University of Cambridge (UK) [ 43 , 44 , 63 , 64 ] who studied different copolymers based on acrylate and methacrylate systems.…”

“…More interesting results were obtained by incorporation of methacrylate moieties in the polysiloxane by Reinhoudt et al . [ 37 ]. However, the synthesis of these siloxane polymers seems to require much effort.…”

Copolymers from oligosiloxane methacrylates as a plasticizer-free membrane matrix for ion-selective sensors

“…The polysiloxanes were obtained by anionic ring-opening copolymerization of hexamethyltrisiloxane with pentamethyltrisiloxanes including the pendant polar and methacrylate group, respectively. Sensors based on such membranes showed good selective responses towards several heavy metal ions [9] and nitrate ions [10]. However, the synthesis of these siloxane monomers and polymers seems to need too much effort.…”

“…However, the non-polar character of polydimethylsiloxane did not allow partition of ions to the membrane to a sufficient degree. Therefore, the polarity of the membranes was increased by introduction of cyano, nitroether, amide, keto or alkylester groups [9,10]. The additional introduction of methacrylate substituents in the polysiloxane chain was used for cross-linking of these membrane polymers by UV curing.…”