title: A portable multi-syringe flow system for spectrofluorimetric determination of iodide in seawater.
abstract: A miniaturized analyzer encompassing a poly(methyl methacrylate) chip with integrated spectrofluorimetric detection and solutions propelling by a multi-syringe module is proposed. Iodide was determined through its catalytic effect on the reaction between Ce(IV) and As(III). Matrix isopotential synchronous fluorescence was explored to set the excitation and emission wavelengths. A two-level full factorial design allowed to evaluate the significance of variables (Ce(IV), As(III) and H2SO4 concentrations) and their interaction effects in the experimental domain. A Doehlert Matrix was applied to identify the critical values. The optimized procedure showed a linear response from 1 to 100 μg L(-1) (S=53.7+2.61C, in which S is the net fluorescence and C is iodide concentration in μg L(-1)). Detection limit, coefficient of variation (n=6) and sampling rate were estimated at 0.3 μg L(-1), 0.8% and 20 h(-1), respectively. Recoveries within 90-117% were estimated for iodide spiked to seawater samples. The proposed procedure stands out because of the portability, robustness, and simplicity for in-field analysis of iodide in seawater.
authors.affiliation: Laboratory of Environmental Analytical Chemistry, University of the Balearic Islands, Carretera de Valldemosa km 7.5, 07122, Palma de Mallorca, Spain.
authors.forename: Rejane M
authors.initials: RM
authors.lastname: Frizzarin
authors.affiliation: Laboratory of Environmental Analytical Chemistry, University of the Balearic Islands, Carretera de Valldemosa km 7.5, 07122, Palma de Mallorca, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Aguado
authors.affiliation: Laboratory of Environmental Analytical Chemistry, University of the Balearic Islands, Carretera de Valldemosa km 7.5, 07122, Palma de Mallorca, Spain.
authors.forename: Lindomar A
authors.initials: LA
authors.lastname: Portugal
authors.affiliation: Laboratory of Environmental Analytical Chemistry, University of the Balearic Islands, Carretera de Valldemosa km 7.5, 07122, Palma de Mallorca, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Moreno
authors.affiliation: Laboratory of Environmental Analytical Chemistry, University of the Balearic Islands, Carretera de Valldemosa km 7.5, 07122, Palma de Mallorca, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Estela
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, P.O. Box 96, 13400-970, Piracicaba, SP, Brazil.
authors.forename: Fábio R P
authors.initials: FR
authors.lastname: Rocha
authors.affiliation: Laboratory of Environmental Analytical Chemistry, University of the Balearic Islands, Carretera de Valldemosa km 7.5, 07122, Palma de Mallorca, Spain. Electronic address: victor.cerda@uib.es.
authors.forename: Victor
authors.initials: V
authors.lastname: Cerdà
mesh_terms: D001151:Arsenic / Q000737:chemistry; D002384:Catalysis; D002586:Cesium / Q000737:chemistry; D057446:Hydrodynamics; D007454:Iodides / Q000032:analysis* / Q000737:chemistry; D057230:Limit of Detection; D015999:Multivariate Analysis; D012623:Seawater / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*; D013594:Syringes
chemical_list: D007454:Iodides; D002586:Cesium; D001151:Arsenic
keywords: Chip; Flow analysis; Fluorescence; MSFIA; Miniaturization; Multivariate optimization