Acetylthiocholine/acetylcholine and thiocholine/choline electrochemical biosensors/sensors based on an organically modified sol–gel glass enzyme reactor and graphite paste electrode

Biosensors based on cholinesterase inhibition for insecticides, nerve agents and aflatoxin B1 detection (review)

“…Another type of immobilisation is the enzyme entrapment in matrix [99][100][101][102][103]. Andreescu et al have reported the immobilisation of ChE by encapsulation in sol-gel prepared by TMSO (Tetramethoxysilane) and MTMSOS (Methyltrimethoxysilane) or by entrapment in poly(vinylalcohol) bearing styrylpyridinium (PVA-SbQ) showing in both cases a storage stability of several months [104].…”

A Novel Ormosil Based Electrocatalytic Biosensor for Glucose/Ethanol Based on Dehydrogenase Modified Electrode

“…The introduction of an electron transfer mediator in the construction of an electrochemical biosensor ultimately involves the occurrence of coupled catalytic reactions, the ®rst one being associated with the regeneration of the enzymatic activity and the second one with the regeneration of the mediator electrochemically. We have studied the mediated electrochemical regeneration of glucose oxidase [7], peroxidase [8], choline oxidase [9] and NADH [10] using mediator and respective enzyme modi®ed graphite paste electrodes in detail. In order to design sensors without further treatment of the electrode surface with relatively high stability applications of sol-gel glassaormosil material have received great attention.…”

“…There is great potential to study ferrocene encapsulatedalinked sol-gel glasses for mediated biosensors applications. We have recently reported a glucose biosensor [19,20,30] based on a sol-gel matrix of controlled porosity followed by putting an enzyme layer and subsequently over that another layer of sol-gel glass of controlled porosity using 3-aminopropyltriethoxysilane and 2-(3,4-epoxycyclohexyl)-ethyltrimethoxy silane as sol-gel glass precursors [9]. We studied both mediated and nonmediated response of the glucose biosensor.…”

Electrochemical Biosensors for Drug Analysis

“…Reversible inhibition of the biosensor response by nicotine which acted on the catalytic activity of ChOX [79,80] and by anti-Alzheimer drug candidates has been described [24,29] In order to avoid the use of ChOX in a two enzyme configuration, the electrochemical monitoring of the catalytic cycle of AChE can be achieved thanks to the use of acetylthiocholine as substrate [29,81]. The biosensor signal corresponds to the electrochemical oxidation of thiocholine on the surface of glassy carbon, carbon paste, or platinum electrode as follows:…”