PVC-based bis(2-nitrophenyl)disulfide sensor for zinc ions

A PVC membrane electrode based on bis(2-nitrophenyl)disulfide carrier exhibits a very good response for Zn2+ in a wide concentration range (from 2.9×10−7 to 3.2×10−2 mol l−1) with a slope of 29.9±0.4 mV per decade of Zn2+ concentration. The response time of the sensor is about 10 s and the membrane can be used for more than 3 months without any observed divergence in potentials. The proposed sensor exhibits very good selectivity for Zn2+ over many cations and can be used in a wide pH range (2–9). This assembly served also as an indicator electrode in potentiometric titrations involving zinc ions and direct potentiometric determination of zinc ions in real and synthetic samples.