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

Fritz, James S.; Arena, Matteo P.; Steiner, Steven A.; Porter, Marc D.

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NASA NTRS · 20040087617

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

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

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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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NASA Program Advanced Human Support Technology Non-NASA Center NASA Discipline Life Sciences Technologies Ions/analysis Spectrum Analysis/methods Colorimetry/methods Copper/analysis Water/chemistry Iodine/analysis Iodides/analysis Support, Non-U.S. Gov't Metals/analysis Silver/analysis Support, U.S. Gov't, Non-P.H.S Chromium/analysis Nickel/analysis Iron/analysis Cations/analysis

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Fritz, James S., Arena, Matteo P., Steiner, Steven A., Porter, Marc D.. 2003-05-16. Rapid determination of ions by combined solid-phase extraction--diffuse reflectance spectroscopy. https://ntrs.nasa.gov/citations/20040087617

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