title: Flow-through solid-phase reflectometric method for simultaneous multiresidue determination of nitrophenol derivatives.
abstract: In this paper, a flow-through optosensor based on diffuse reflectance spectroscopy and multivariate regression modelling is proposed for simultaneous multiresidue determination of trace level concentrations of nitro-substituted phenols. The optrode integrates on-line anion-exchange sorptive preconcentration and matrix removal with direct detection of sorbed species onto the sensing layer and chemometric deconvolution of overlapped spectra. After recording of the reflectometric spectrum, fast chemosensor regeneration is accomplished with an acidic methanolic eluent followed by a metered volume of alkaline solution. The full automation of the analytical procedure is ensured by flow-programming as executed via a software-controlled multisyringe pump and a set of multiposition and solenoid valves. Under the optimized chemical and physical variables, the 3sigma(blank) detection limits for 2-, and 4-nitrophenol and 2,4-dinitrophenol were 0.69, 0.42 and 0.37mugL(-1), respectively, for a sample loading volume of 4.0mL with enrichment factors of 73, 74 and 81, respectively, and repeatability better than 3.0%. The analytical applicability of the optosensing system was asserted by the satisfactory results attained in its application to monitoring of nitrophenol derivatives in spiked environmental waters including highly saline matrices via the standard additions method.
authors: Department of Chemistry, Faculty of Sciences, University of Balearic Islands, Carretera de Valldemossa km 7.5, E-07122 Palma de Mallorca, Spain.
authors: Matías
authors: M
authors: Manera
authors: Manuel
authors: M
authors: Miró
authors: José Manuel
authors: JM
authors: Estela
authors: Víctor
authors: V
authors: Cerdà
authors: Marcela A
authors: MA
authors: Segundo
authors: José L F C
authors: JL
authors: Lima
mesh_terms: D004058:Diffusion; D017022:Flow Injection Analysis / Q000295:instrumentation* / Q000379:methods*; D009596:Nitrophenols / Q000032:analysis* / Q000737:chemistry*; D012107:Research Design; D052616:Solid Phase Extraction / Q000295:instrumentation* / Q000379:methods*; D012996:Solutions; D013057:Spectrum Analysis
chemical_list: D009596:Nitrophenols; D012996:Solutions