title: Label-free disposable immunosensor for detection of atrazine.
abstract: This work reports the construction of a fast, disposable, and label-free immunosensor for the determination of atrazine. The immunosensor is based on a field effect transistor (FET) where a network of single-walled carbon nanotubes (SWCNTs) acts as the conductor channel, constituting carbon nanotubes field effect transistors (CNTFETs). Anti-atrazine antibodies were adsorbed onto the SWCNTs and subsequently the SWCNTs were protected with Tween 20 to prevent the non-specific binding of bacteria or proteins. The principle of the immunoreaction consists in the direct adsorption of atrazine specific antibodies (anti-atrazine) to SWCNTs networks. After exposed to increasing concentrations of atrazine, the CNTFETs could be used as useful label-free platforms to detect atrazine. Under the optimal conditions, a limit of detection as low as 0.001 ng mL(-1) was obtained, which is lower than that of other methods for the atrazine detection, and in a working range between 0.001 and 10 ng mL(-1). The average recoveries obtained for real water samples spiked with atrazine varied from 87.3% to 108.0%. The results show that the constructed sensors display a high sensitivity and could be useful tools for detecting pesticides like atrazine at low concentrations. They could be also applied to the determination of atrazine in environmental aqueous samples, such as seawater and riverine water.
authors.affiliation: Laboratory of Water, Energy and Environment, National School of Engineers of Sfax (ENIS), University of Sfax, Route de Soukra Km 3,5 P.O. Box 1173, 3038 Sfax, Tunisia. Electronic address: belkamssanajet@yahoo.fr.
authors.forename: Najet
authors.initials: N
authors.lastname: Belkhamssa
authors.affiliation: Department of Chemistry & CESAM, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal; ISEIT/Viseu, Instituto Piaget, Estrada do Alto do Gaio, Galifonge, 3515-776 Lordosa, Viseu, Portugal.
authors.forename: Celine I L
authors.initials: CI
authors.lastname: Justino
authors.affiliation: Department of Chemistry & CESAM, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Patrícia S M
authors.initials: PS
authors.lastname: Santos
authors.affiliation: INESC-MN, Rua Alves Redol 9, 1000-029 Lisbon, Portugal.
authors.forename: Susana
authors.initials: S
authors.lastname: Cardoso
authors.affiliation: Department of Biology & CESAM, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Lopes
authors.affiliation: Department of Chemistry & CESAM, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Armando C
authors.initials: AC
authors.lastname: Duarte
authors.affiliation: Department of Chemistry & CESAM, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Teresa
authors.initials: T
authors.lastname: Rocha-Santos
authors.affiliation: Laboratory of Water, Energy and Environment, National School of Engineers of Sfax (ENIS), University of Sfax, Route de Soukra Km 3,5 P.O. Box 1173, 3038 Sfax, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ksibi
mesh_terms: D001280:Atrazine / Q000032:analysis*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004209:Disposable Equipment; D004867:Equipment Design; D007118:Immunoassay / Q000295:instrumentation*; D037742:Nanotubes, Carbon / Q000737:chemistry; D045483:Rivers / Q000737:chemistry; D012623:Seawater / Q000737:chemistry; D014173:Transistors, Electronic; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D037742:Nanotubes, Carbon; D014874:Water Pollutants, Chemical; D001280:Atrazine
keywords: Atrazine; Carbon nanotubes; Field effect transistor; Immunosensor