Pressure-driven mesofluidic platform integrating automated on-chip renewable micro-solid-phase extraction for ultrasensitive determination of waterborne inorganic mercury.
Talanta
; 110: 58-65, 2013 Jun 15.
Article
em En
| MEDLINE
| ID: mdl-23618176
A dedicated pressure-driven mesofluidic platform incorporating on-chip sample clean-up and analyte preconcentration is herein reported for expedient determination of trace level concentrations of waterborne inorganic mercury. Capitalizing upon the Lab-on-a-Valve (LOV) concept, the mesofluidic device integrates on-chip micro-solid phase extraction (µSPE) in automatic disposable mode followed by chemical vapor generation and gas-liquid separation prior to in-line atomic fluorescence spectrometric detection. In contrast to prevailing chelating sorbents for Hg(II), bare poly(divinylbenzene-N-vinylpyrrolidone) copolymer sorptive beads were resorted to efficient uptake of Hg(II) in hydrochloric acid milieu (pH=2.3) without the need for metal derivatization nor pH adjustment of prior acidified water samples for preservation to near-neutral conditions. Experimental variables influencing the sorptive uptake and retrieval of target species and the evolvement of elemental mercury within the miniaturized integrated reaction chamber/gas-liquid separator were investigated in detail. Using merely <10 mg of sorbent, the limits of detection and quantification at the 3s(blank) and 10s(blank) levels, respectively, for a sample volume of 3 mL were 12 and 42 ng L(-1) Hg(II) with a dynamic range extending up to 5.0 µg L(-1). The proposed mesofluidic platform copes with the requirements of regulatory bodies (US-EPA, WHO, EU-Commission) for drinking water quality and surface waters that endorse maximum allowed concentrations of mercury spanning from 0.07 to 6.0 µg L(-1). Demonstrated with the analysis of aqueous samples of varying matrix complexity, the LOV approach afforded reliable results with relative recoveries of 86-107% and intermediate precision down to 9% in the renewable µSPE format.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Automação
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Poluentes Químicos da Água
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Microfluídica
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Extração em Fase Sólida
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Mercúrio
Idioma:
En
Revista:
Talanta
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Holanda