Original Articles: 2011 Vol: 3 Issue: 3
Determination of fluoride ions in mouth wash samples by a Neodymium (III)-PVC Membrane Sensor
Abstract
5-(methylsulfanyl)-3-phenyl-1H-1,2,4-triazole (MPT) has been used as a suitable ionophore and nitrobenzene (NB) as a plasticizer in order to develop a PVC-based membrane electrode for neodymium ion detection. The sensors exhibits Nernstian response for the Nd3+ ions over the concentration range 1.0 × 10-6-1.0 × 10-2 M at pH 3.0-7.6 with a lower detection limit of 5.9 × 10-7 M. The sensors displays Nernstian slope of 19.8 ± 0.4 mV per decade for Nd(III) ions. The response time was relatively quick in the whole concentration range (~5 s). The electrode shows a good selectivity for Nd(III) ion with respect to most common cations including alkali, alkaline earth, transition and heavy metal ions. The developed sensor was successfully applied as an indicator electrode in the Nd(III) ion potentiometric titration with EDTA, the F– ions determination in some mouth washing solutions.