title: Fully integrated ready-to-use paper-based electrochemical biosensor to detect nerve agents.
abstract: Paper-based microfluidic devices are gaining large popularity because of their uncontested advantages of simplicity, cost-effectiveness, limited necessity of laboratory infrastructure and skilled personnel. Moreover, these devices require only small volumes of reagents and samples, provide rapid analysis, and are portable and disposable. Their combination with electrochemical detection offers additional benefits of high sensitivity, selectivity, simplicity of instrumentation, portability, and low cost of the total system. Herein, we present the first example of an integrated paper-based screen-printed electrochemical biosensor device able to quantify nerve agents. The principle of this approach is based on dual electrochemical measurements, in parallel, of butyrylcholinesterase (BChE) enzyme activity towards butyrylthiocholine with and without exposure to contaminated samples. The sensitivity of this device is largely improved using a carbon black/Prussian Blue nanocomposite as a working electrode modifier. The proposed device allows an entirely reagent-free analysis. A strip of a nitrocellulose membrane, that contains the substrate, is integrated with a paper-based test area that holds a screen-printed electrode and BChE. Paraoxon, chosen as nerve agent simulant, is linearly detected down to 3µg/L. The use of extremely affordable manufacturing techniques provides a rapid, sensitive, reproducible, and inexpensive tool for in situ assessment of nerve agent contamination. This represents a powerful approach for use by non-specialists, that can be easily broadened to other (bio)systems.
authors.affiliation: Department of Chemical Sciences and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy. Electronic address: stefano.cinti@uniroma2.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Cinti
authors.affiliation: Department of Chemical Sciences and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy.
authors.forename: Clarissa
authors.initials: C
authors.lastname: Minotti
authors.affiliation: Department of Chemical Sciences and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy.
authors.forename: Danila
authors.initials: D
authors.lastname: Moscone
authors.affiliation: Department of Chemical Sciences and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Palleschi
authors.affiliation: Department of Chemical Sciences and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy. Electronic address: fabiana.arduini@uniroma2.it.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Arduini
mesh_terms: D015374:Biosensing Techniques; D002091:Butyrylcholinesterase / Q000737:chemistry; D002092:Butyrylthiocholine / Q000737:chemistry; D002619:Chemical Warfare Agents / Q000737:chemistry / Q000302:isolation & purification*; D055664:Electrochemical Techniques; D006801:Humans; D056656:Lab-On-A-Chip Devices; D000067397:Nerve Agents / Q000302:isolation & purification* / Q000633:toxicity; D010209:Paper; D010261:Paraoxon / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D002619:Chemical Warfare Agents; D000067397:Nerve Agents; D002092:Butyrylthiocholine; D002091:Butyrylcholinesterase; D010261:Paraoxon
keywords: Enzyme inhibition; Nerve agents; Paper-based biosensor; Paraoxon; Reagentless; Screen-printing