Novel platinum(II) selective membrane electrode based on 1,3-bis(2-cyanobenzene)triazene.

A plasticized poly (vinyl chloride) membrane electrode based on 1,3-bis(2-cyanobenzene)triazene (CBT) for highly selective determination of platinum(II) (in PtCl(4)(2-) form) is developed. The electrode showed a good Nernstian response (29.8+/-0.3 mV decade(-1)) over a wide concentration range (1.0 x 10(-6) to 1.0 x 10(-2)mol L(-1)). The limit of detection was 5.0 x 10(-7)mol L(-1). The electrode has a response time of about 40s, and it can be used for at least 1 month without observing any considerable deviation from Nernstian response. The proposed electrode revealed an excellent selectivity toward platinum(II) ion over a wide variety of alkali, alkaline earth, transition, and heavy metal ions, and it could be used in the pH range of 3.2-5.1. The practical utility of the electrode has been demonstrated by its use in determination of platinum ion in, alloy, tap, mineral and river water samples.