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Cobalt(II)-selective membrane sensor based on a [Me2(13)dieneN4] macrocyclic cobalt complex.

Ashok Kumar Singh·Puja Saxena·Sameena Mehtab·Amit Panwar
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Abstract

A new poly(vinyl chloride)-based membrane was fabricated with the cobalt(II) complex of 2,4-dimethyl-1,5,8,11-tetraazacyclotrideca-1,4-diene [Me2(13)dieneN4] as an ion carrier. The membrane composition was Co2+ complex/PVC/NaTPB/DBP 15:50:15:20 (w/w). The sensor exhibited a Nernstian response for Co2+ ions over a wide concentration range (7.94x10(-6)-1.0x10(-1) M) at pH 2.5-7.0, a response time of 10 s, and it could be used for 3 months without any significant divergence in potential. The proposed membrane sensor exhibited good selectivity for Co2+ over a wide variety of other metal ions and in mixtures containing up to 25% (v/v) non-aqueous content. The sensor was successfully used as an indicator electrode in the potentiometric titration of Co2+ with EDTA and the direct determination of Co2+ in real samples.

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Biosensing TechniquesCobaltMacrocyclic CompoundsMembranes, ArtificialOrganometallic CompoundsTitrimetryJournal ArticleResearch Support, Non-U.S. Gov't

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Ashok Kumar Singh, Puja Saxena, Sameena Mehtab, Amit Panwar. 2006-06-23. Cobalt(II)-selective membrane sensor based on a [Me2(13)dieneN4] macrocyclic cobalt complex.. https://doi.org/10.1007/s00216-006-0544-9

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