Europium (III) PVC membrane sensor based on N-pyridine-2-carboxamido-8-aminoquinoline as a sensing material

Conductometric study in acetonitrile solution shows the selectivity of PCQ toward europium ion. Therefore, a new europium PVC membrane electrode was prepared based on N-pyridine-2-carboxamido-8-aminoquinoline (PCQ) as an ion carrier. The electrode has a wide concentration range from 1.0 × 10− 2 and 1.0 × 10− 6 mol L− 1, Nernstian slope of 19.8 ± 0.3 mV per decade and a detection limit of 6.4 × 10− 7 mol L− 1. The potentiometric response is pH independent in the range of 2.4–7.4. The proposed sensor has a relatively fast response time less than 10 s and it can be used for at least 2 months without any considerable divergence in its potentials. The proposed electrode revealed good selectivity toward europium ion in comparison with variety of other metal ions. The practical utility of the electrodes has been demonstrated by their use as indicator electrodes in the potentiometric titration of Eu3 + ions with EDTA and for determination of Eu3 + ion concentration in mixtures of two and three different ions.

► A new ion carrier is introduced to preparation of a selective sensor for Eu3 + ions.
► This technique is very simple and it's not necessary to use sophisticated equipment.
► The novelty of this work is the high affinity of the ionophore toward the Eu3 + ions.
► The sensor is superior to the formerly reported Eu3 + sensors in terms of selectivity.