Polymeric membrane silver-ion selective electrodes based on bis(dialkyldithiophosphates)

Poly(vinyl chloride) (PVC) membrane electrodes based on bis(dialkyldithiophosphates) carriers were prepared and tested for selective detection of silver ions. A suitable lipophilicity of the carrier and appropriate co-ordination ability were found to be essential for designing an electrode with good response characteristics. A PVC membrane with 5% bis(diethyldithiophosphates) ionophore and 65% o-NPOE plasticizer satisfies these requirements. This electrode exhibits linear response over a concentration range of 10(-1)-10(-6) mol l(-1) Ag+ with a slope of 57.3 mV/dec. This is a fast and simple analytical method, and it has been applied successfully in the determination of silver ions in electroplating wastewater. (C) 2000 Elsevier Science B.V. All rights reserved.