A mercury selective sensor based on a novel biomimetic recognition element and nano-composite carbon paste electrode is introduced. The artificial host was imprinted in vinyl pyridine based cross-linked polymer. The nano-composite paste were made of ion imprinted polymer (IIP) as a sensing element, multi-walled carbon nanotube (MWCNT), nanosilica (NS), graphite powder, and room temperature ionic liquid (RTIL). The best results were obtained from the nano-composite sensor with the electrode composition of 5% MWCNT, 1% NS, 15% IIP, 10% RTIL, and 69% graphite powder. The proposed sensor shows a Nernstian response (31.1 ± 0.2 mV decade-1) in the range of 1.0 x 10-7 - 1.0 x 10-2 M with detection limit of 1.0 x 0-7 M. The response of the sensor is independent of pH in the range of 3.5-9.0. The nano-composite based Hg(II) sensor displayed very good selectivity, response time, and specially, lifetime.
Template and target information: mercury ions, Hg(II)
Author keywords: Ion Imprinted Polymer (MIP), mercury, sensor, Potentiometry, Ionic Liquids, Multi-walled carbon nanotube (MWCNT), Nanosilica (NS)