Application of some recently synthesized 9, 10-anthraquinone derivatives as new class of ionophores responsive to lead (II) ion

Lead-selective solvent polymeric membrane electrodes, based on some recently synthesized 9, 10-anthraquinone derivatives, are described. The electrode exhibits a good Nernstian response for Pb (II) ions over a wide concentration range of 1.0/spl times/10/sup -6/-1.0/spl times/10/sup -2/ M with a slope of 28.9 mV decade/sup -1/. The potential-pH profile of membrane based on 1-hydroxy-2-({2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}methyl)anthra-9, 10-quinone (A/sub 3/) demonstrated a lack of H/sup +/ interference within a wide pH range (1.5-6.8). The detection limit is 6.7/spl times/10/sup -7/ M. The developed sensor has a very short response time (2.0 s), and it can be used as a working electrode in a flow injection system. The lifetime of the proposed sensor is 120 days (without any considerable divergence in potentials) with good reproducibility (SD=/spl plusmn/0.1 mV). The proposed sensor revealed good selectivity for Pb (II) over a wide variety of other metal ions. It can be used as an indicator electrode in the potentiometric titration of lead ions, with EDTA, oxalate, chromate, and hydroxide ions, and in direct determination of lead in a wastewater sample.