Microfluidic polymer chip with an embedded ion-selective electrode detector for nitrate-ion assay in environmental samples

Takashi Masadome, Kazuki Nakamura, Daisuke Iijima, Osamu Horiuchi, Benjaporn Tossanaitada, Shin ichi Wakida, Toshihiko Imato

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10 Citations (Scopus)

Abstract

A nitrate ion-selective electrode (NO3--ISE) has been developed based on tetradodecylammonium bromide as an anion exchanger and 2-nitrophenyl octyl ether as a plasticizer. The NO3--ISE shows an almost Nernstian response to nitrate ion over a concentration range between 1.0 × 10-6 and 1.0 × 10-1 M, with an anionic slope of -57.7 ± 0.7 mV/decade. The selectivity coefficients of the NO3--ISE for nitrate ion against chloride and sulfate were obtained. A microfluidic polymer chip was fabricated using polystyrene plates and stainless-steel wires as a template for the channel. The microfluidic polymer chip is composed of a mixing chip and a NO3--ISE detector chip. The microfluidic polymer chip, integrated with a NO3--ISE detector consisting of the NO3--ISE and a Na+-ISE as a reference electrode, showed an almost Nernstian response to nitrate ion over a concentration range between 1.0 × 10-5 and 1.0 × 10-1 M, with an anionic slope of -54.3 ± 1.3 mV/decade. The microfluidic polymer chip was then applied to the determination of nitrate ion in environmental water samples, such as a tap water, a well-water sample and water for agricultural use. 2010

Original languageEnglish
Pages (from-to)417-423
Number of pages7
JournalAnalytical Sciences
Volume26
Issue number4
DOIs
Publication statusPublished - 2010 Apr

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ASJC Scopus subject areas

  • Analytical Chemistry

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