A selective membrane electrode for iodide ion based on a thiopyrilium ion derivative as a new ionophore

摘要

A highly selective electrode for iodide ion based on a thiopyrilium derivative as an excellent ionophore is described. At pH 5.5-8.0, the electrode responds to iodide ion in a linear range from 1.0 X 10(-1) to 8.0 X 10(-7) M with a slope of 60.2 mV per decade, and a detection limit of 2.0 X 10(-1) M. Selectivity coefficients determined with the match potential method (MPM) indicate that the interference from inorganic and organic anions is very small. The proposed sensor shows a fast response time of approximately 15 s. It was applied as an indicator electrode in titration of iodide with Ag+. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 47]