Mercury(II) selective membrane electrode based on 1,3-bis(2-methoxybenzene)triazene

A plasticized poly (vinyl chloride) membrane electrode based on 1,3-bis(2-methoxybenzene)triazene (MBT) for highly selective determination of mercury(II) has been developed. The electrode showed a good Nernstian response (30.2 +/- 03 mV decade(-1)) over a wide concentration range (1.0 x 10(-7) - 1.0 x 10(-2) mol L-1). The limit of detection was 5.0 x 10(-8) mol L-1. The electrode has a response time about 15 s and can be used for at least 1 month without observing any deviation from Nernstain response. The proposed electrode revealed an excellent selectivity toward mercury(II) ion over a wide variety of alkali, alkaline earth, transition, and heavy metal ions and could be used in the pH range 2.6-4.2. The electrode was used in the determination of Hg2+ in aqueous samples and as an indicator electrode in potentiometric titration of Hg(II) ions. (C) 2009 Elsevier B.V. All rights reserved.