A PVC‐based benzo‐15‐crown‐5 membrane sensor for cadmium

A plasticized poly (vinyl chloride) (PVC)‐based membrane of benzo‐l5‐crown‐5 exhibits a good response for Cd 2+ in a wide concentration range (3.16 × 10 5 −1.00 × 10 −1 M) with a slope of 20mV per decade of [Cd 2− ]. The response time of the membrane sensor is < 30 s and the same can be used in a pH range 3.8 to 7.0. The electrode has been used, at one stretch, for a period of two months and displays good selectivity for Cd 2+ over alkali, alkaline earth and transition metal ions. The membrane sensor has also been used as an indicator electrode in potentiometric titration involving cadmium( II ) ions.