Rare elements electrochemistry: the development of a novel electrochemical sensor for the rapid detection of Europium in environmental samples using gold electrode modified with 2-pyridinol-1-oxide.

This work presents for the first time the electrochemical determination of europium using cyclic voltammetry at gold electrodes modified with 2-pyridinol-1-oxide. A well-defined oxidation peak was observed in cyclic voltammetry as a result of the oxidation of the europium at ~1100 mV in phosphate buffer at pH 7.0. The peak current increased linearly with the increase of concentration of the europium over the range from 1 to 80 ?M and detection limit (based on 3-sigma) and quantification were found to be 0.3 and 0.549 ?M, respectively. The analytical utility of the developed protocol was evaluated by performing the detection of the europium in river water. Europium is also linear over the concentration range 10 to 150 ?M. (I p /?A = 0.7239x + 108.19, R 2 = 0.9981 and n = 9) with a detection limit of 6.5 ?M (based on 3-sigma). This simple and effective protocol exhibited good sensitivity, precision and reliability towards the detected analyte