title: Screen-printed electrode modified with carbon black and chitosan: a novel platform for acetylcholinesterase biosensor development.
abstract: We report a screen-printed electrode (SPE) modified with a dispersion of carbon black (CB) and chitosan by drop casting. A cyclic voltammetry technique towards ferricyanide, caffeic acid, hydroquinone, and thiocholine was performed and an improvement of the electrochemical response with respect to bare SPE as well as SPE modified only with chitosan was observed. The possibility to detect thiocholine at a low applied potential with high sensitivity was exploited and an acetylcholinesterase (AChE) biosensor was developed. A dispersion of CB, chitosan, and AChE was used to fabricate this biosensor in one step by drop casting. The enzymatic activity of the immobilized AChE was determined measuring the enzymatic product thiocholine at +300 mV. Owing to the capability of organophosphorus pesticides to inhibit AChE, this biosensor was used to detect these pollutants, and paraoxon was taken as model compound. The enzyme inhibition was linearly related to the concentration of paraoxon up to 0.5 μg L(-1), and a low detection limit equal to 0.05 μg L(-1) (calculated as 10% of inhibition) was achieved. This biosensor was challenged for paraoxon detection in drinking waters with satisfactory recovery values. The use of AChE embedded in a dispersion of CB and chitosan allowed an easy and fast production of a sensitive biosensor suitable for paraoxon detection in drinking waters at legal limit levels. Graphical Abstract Biosensors based on screen-printed electrodes modified with Acetylcholinesterase, Carbon Black, and Chitosan for organophosphorus pesticide detection.
authors.affiliation: Department of Chemical Science and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133, Rome, Italy.
authors.forename: Daria
authors.initials: D
authors.lastname: Talarico
authors.affiliation: Department of Chemical Science and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133, Rome, Italy. fabiana.arduini@uniroma2.it.|Biostructures and Biosystems National Institute, Viale Medaglie d'Oro 305, 00136, Rome, Italy. fabiana.arduini@uniroma2.it.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Arduini
authors.affiliation: Faculté de Sciences et Techniques Laboratoire Génie des Procédés et Environnement, Université Hassan II-Mohammedia de Casablanca, B.P. 146, 20650, Mohammadia, Morocco.
authors.forename: Aziz
authors.initials: A
authors.lastname: Amine
authors.affiliation: Engineering Department, University of Rome "Niccolò Cusano", Via Don Carlo Gnocchi 3, 00166, Rome, Italy.|Italian Interuniversity Consortium on Materials Science and Technology (INSTM), Rome, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Cacciotti
authors.affiliation: Department of Chemical Science and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133, Rome, Italy.|Biostructures and Biosystems National Institute, Viale Medaglie d'Oro 305, 00136, Rome, Italy.
authors.forename: Danila
authors.initials: D
authors.lastname: Moscone
authors.affiliation: Department of Chemical Science and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133, Rome, Italy.|Biostructures and Biosystems National Institute, Viale Medaglie d'Oro 305, 00136, Rome, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Palleschi
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry*; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D048271:Chitosan / Q000737:chemistry*; D002800:Cholinesterase Inhibitors / Q000032:analysis; D060766:Drinking Water / Q000032:analysis; D004566:Electrodes; D004593:Electrophorus / Q000378:metabolism; D004800:Enzymes, Immobilized / Q000737:chemistry; D007306:Insecticides / Q000032:analysis; D057230:Limit of Detection; D010261:Paraoxon / Q000032:analysis*; D053260:Soot / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002800:Cholinesterase Inhibitors; D060766:Drinking Water; D004800:Enzymes, Immobilized; D007306:Insecticides; D053260:Soot; D014874:Water Pollutants, Chemical; D048271:Chitosan; D000110:Acetylcholinesterase; D010261:Paraoxon
keywords: Acetylcholinesterase biosensor; Amperometric detection; Carbon black; Chitosan; Paraoxon; Pesticides