A dynamic electrochemical sensor for europium(III)

摘要

A new calixarenederivative, i.e., p-tert-butylcalix[4]arenehas been used as an excellent ionophore in the construction of a novel PVCbased Eu(III)-selective electrode. A master membrane with percentagecomposition of PVC:DBP:L: NaTPB:: 32:55:4:9 gives the best results. Themembrane electrode exhibits a nernstian response with the slope of 19.7±1.0 mV/decade over a wide concentration range of 9.1 × 10-8-1.0× 10-1 M and withdetection limit of 8.8 × 10-8 M.The effects of membrane composition and pHas well as the influence of the anionic additive on the electrode performancehave been investigated. The potential response of the resulting sensor is notinfluenced in the pH range 3.0-9.0.Moreover, the membrane electrode has a good reproducibility (RSD 3%), very fastresponse time (5 s) and ability to detect Eu(III) among other rare earth metaland common cations. The membrane sensor works satisfactorily up to 40%non-aqueous medium and can be used over a period of 6 months. The sensor hasbeen successfully applied for the determination of Eu(III) in analytical andbiological samples (urine and serum) and also acts as an electrode indicator.