A New Potentiometric Sensor for Determination of Cesium ion in Environmental samples

Document Type : Original Research Paper


1 Department of Chemistry, Islamic Azad University, Central Tehran Branch, Tehran, Iran

2 Department of waste Management, NFRS, Nuclear Science and Technology Institute, AEOI, P. O. Box 11365-3486, Tehran, Iran

3 Graduate Faculty of Environment, University of Tehran, P.O. Box 14155-6135, Tehran, Iran


A new cesium ion selective PVC membrane based on parent calix [4] arene was developed for
potentiometric determination of cesium in environmental samples. The electrode based on p-5,11,17,23tetra(tertbutyl)
25,26,27,28-tetrahydroxy calix[4]arene(THC) as ionophor ,dibutyl phthalate (DBP)as plasticizer ,sodium
tetra phenyl borate(NaTPB)and oleic acid as lipophilic salt and additive showed the best performance. The
electrode exhibits a good Nernstian response in a concentration range of 1×10-1-3.16×10−5 M of cesium, with
a slope of 58.5 ± 0.6mv per decade and a detection limit of 1.58×10−5 M.It exhibits a good selectivity for
cesium in comparison with alkali, alkaline earth, and some transition metal ions. The electrode response and
selectivity remained almost unchanged for more than a month. The effect of membrane composition, pH and
concentration of internal solution on the potential response of the electrode were also studied. The applicability
of the electrode to real samples was also assessed.