title: A rational design of the multiwalled carbon nanotube-7,7,8,8-tetracyanoquinodimethan sensor for sensitive detection of acetylcholinesterase inhibitors.
abstract: A new, simple and effective amperometric acetylcholinesterase biosensor was developed using screen-printed carbon electrodes modified with carbon nanotubes (MWCNTs)-7,7,8,8-tetracyanoquinodimethane (TCNQ). The design of the biosensor was based on the supramolecular arrangement resulted from the interaction of MWCNTs and TCNQ. This arrangement was confirmed by spectroscopic and electrochemical techniques. Two different supramolecular arrangements were proposed based on different MWCNTs:TCNQ ratios. The synergistic effect of MWCNTs and TCNQ was, for the first time, exploited for detection of thiocholine at low potential with high sensitivity. The biosensor developed by immobilization of acetylcholinesterase (AChE) in sol-gel allowed the detection of two reference AChE inhibitors, paraoxon-methyl and chlorpyrifos with detection limits of 30 pM (7 ppt) and 0.4 nM (0.1 ppb), respectively. Efficient enzyme reactivation was obtained by using obidoxime.
authors.affiliation: Department of Analytical Chemistry, University of Bucharest, 4-12 Regina Elisabeta Blvd., 030018 Bucharest, Romania.
authors.forename: Lucian
authors.initials: L
authors.lastname: Rotariu
authors.forename: Lucian-Gabriel
authors.initials: LG
authors.lastname: Zamfir
authors.forename: Camelia
authors.initials: C
authors.lastname: Bala
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods / Q000639:trends; D002800:Cholinesterase Inhibitors / Q000737:chemistry*; D057230:Limit of Detection; D008958:Models, Molecular; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009570:Nitriles / Q000737:chemistry*
chemical_list: D002800:Cholinesterase Inhibitors; D037742:Nanotubes, Carbon; D009570:Nitriles; C013703:tetracyanoquinodimethane