Potentiometric sensor for hydrogen ion based on N,N '-dialkylbenzylethylenediamine neutral carrier in a poly(vinyl chloride) membrane with polyaniline solid contact

Hydrogen ion selective solid contact electrodes based on N,N'-dialkylbenzyl elhylenediamine (alkyl = butyl, hexyl, octy, decyl) are prepared. Solid con tact electrodes and coated wire electrodes have been fabricated from polyme r cocktail solutions based on N.N'-dialkylbenzylethylenediamine (alkyl = bu tyl, hexyl, octy, decyl). We showed that the response range and slopes are influenced by the alkyl chain length. Response ranges and Nernstian slops f or solid contact electrodes were slightly better than for coated wire elect rodes. Solid contact electrodes were shown linear selective to hydrogen ion in the pH ranges pH 4.5-13.0, 4.2-13.1. 3.4-13.0 and 3.0-13.2. and their N ernstian slopes were 49.7, 50.8, 51.5 and 53.7 mV pH(-1) at 20 +/- 0.2 degr eesC, respectively. Stability is also improved especially when compared wit h coated wire electrodes. The 90% response time was < 2 s and their electri cal resistance varied in the range 2.37-2.76 M<Omega>. Especially solid con tact electrodes with N,N'-didecylbenzylethylenediamine have shown the best selectivity and reproducibility of e.m.f.. (C) 2001 Elsevier Science B.V. A ll rights reserved.