A novel, sensitive, reusable and low potential acetylcholinesterase biosensor for chlorpyrifos based on 1-butyl-3-methylimidazolium tetrafluoroborate/multiwalled carbon nanotubes gel

Cholinesterase Biosensors Based on Screen‐Printed Electrodes Modified with Co‐Phtalocyanine and Polycarboxylated Thiacalixarenes

“…Recently we have shown that single-walled carbon nanotubes covalently attached to AChE and deposited onto the screenprinted electrodes modified with Co-phtalocyanine significantly reduced the working potential of thiocholine oxidation to 150 mV with high sensitivity of the signal toward organophosphate pesticides [16]. Similar results were obtained with a paste electrode manufactured from carbon nanotubes mixed with ionic liquid and covered with AChE entrapped in organosilica gel [14].…”

“…Their implementation in the surface layer significantly decreases the overvoltage of the electrode reaction and improves reproducibility and sensitivity of the signal toward a substrate and, to some extent, an inhibitor. Carbon nanotubes exert similar effect [11][12][13][14] but are commonly combined with some mediators to increase the efficiency of the signal detection [15][16][17]. Recently we have shown that single-walled carbon nanotubes covalently attached to AChE and deposited onto the screenprinted electrodes modified with Co-phtalocyanine significantly reduced the working potential of thiocholine oxidation to 150 mV with high sensitivity of the signal toward organophosphate pesticides [16].…”

Acetylcholinesterase biosensor based on self-assembled monolayer-modified gold-screen printed electrodes for organophosphorus insecticide detection

“…The AChE biosensor, in fact, can be reactivated putting in contact the biosensor, after the measurement, for several minutes with 2-PAM (pyridine-2-aldoxime methyliodide) solution [25] or, for example, obidoxime solution [26]. The reactivation should be performed immediately after the measurement, in order to avoid the enzyme phenomenon called "ageing" that renders the inhibited enzyme more resistant to the reactivation becoming permanently inhibited [27].…”

Recent advances in biosensors based on enzyme inhibition

“…CNTs were not only used alone as previously reported, but also combined with other materials in order to modify the sensor with novel nanocomposites such as 7,7,8,8-tetracyanoquinodimethane , chitosan-prussian blue-hollow gold nanospheres (Zhai et al, 2013), Cophtalocyanine , β-cyclodextrin (Du et al, 2010a), gold nanoparticles (Du et al, 2010b), polypyrrole and polyaniline (Du et al 2010c) and ionic liquids such as imidazolium-based ionic liquids (Zamfir et al, 2011). The use of nanocomposites allows for detecting the inhibitors at very low detection limit, but very often requires high potential, even higher than the sensor modified with only carbon nanotubes.…”