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PubMed · 12830875

Rapid determination of ions by combined solid-phase extraction--diffuse reflectance spectroscopy.

James S Fritz·Matteo P Arena·Steven A Steiner·Marc D Porter
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Abstract

We introduce colorimetric solid-phase extraction (C-SPE) for the rapid determination of selected ions. This new technique links the exhaustive concentration of an analyte by SPE onto a membrane disk surface for quantitative measurement with a hand-held diffuse reflectance spectrometer. The concentration/measurement procedure is complete in approximately 1 min and can be performed almost anywhere. This method has been used to monitor iodine and iodide in spacecraft water in the 0.1-5.0 ppm range and silver(I) in the range of 5.0-1000 microg/l. Applications to the trace analysis of copper(II), nickel(II), iron(III) and chromium(VI) are described. Studies on the mechanism of extraction showed that impregnation of the disk with a surfactant as well as a complexing reagent results in uptake of additional water, which markedly improves the extraction efficiency.

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CationsChromiumColorimetryCopperIodidesIodineIonsIronMetalsNickelSilverSpectrum AnalysisWaterNASA Discipline Life Sciences TechnologiesNASA Program Advanced Human Support TechnologyNon-NASA CenterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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James S Fritz, Matteo P Arena, Steven A Steiner, Marc D Porter. 2003-05-16. Rapid determination of ions by combined solid-phase extraction--diffuse reflectance spectroscopy.. https://doi.org/10.1016/s0021-9673(03)00551-x

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