New potentiometric membrane sensors responsive to Pb(II) based on some recently synthesized 9,10-anthraquinone derivatives

New potentiometric membrane sensors responsive to Pb(II) have been developed, The membrane sensors are based on three different 9, 10-anthraquinone derivatives. The electrode based on 1,4-bis (prop-2'-enyloxy)-9, 10-anthraquinone exhibits a good Nernstian response for Pb(II) ions over a wide concentration range ( 2.5x10(-6) - 1.0x10(-2) M) With a slope of 29.8 mV decade(-1). Detection limit is 1.5x10(-6) M. The response time of the sensor is 15s and the useful working pH range is 3.7-6.8. The membrane can be used for more than 4 months without any considerable divergence in potentials. The electrodes revealed comparatively good selectivities with respect to alkali, alkaline earth and some transition and heavy metal ions. It was used as an indicator electrode in potentiometric titration of lead ions (with sulfate and oxalate lolls), and for the determination of lead in waste waters.