Designing and Optimizing a Novel Microsensor for Monitoring Sub-nano Molar Lutetium (III) Ions in the Environment

Electrochemical microsensors are very important tools in analyzing trace amount of pollutants in oil, petrochemical and gas industries. In this work, for the first time, we introduce a highly selective and sensitive lutetium (III) micro-sensor. N-(2-furylmethylene) pyridine-2,6- diamine (FPD) was used as a membrane-active component to prepare a highly sensitive Lu(III)- selective polymeric membrane microelectrode. The best performance was achieved with a membrane composition of 32% PVC, 60% o-nitrophenyloctyl ether, 4% potassium tetrakis (pchlorophenyl) borate (KTpClPB) and 4% FPD. The electrode exhibits a Nernstian response for Lu (III) ions over a particular concentration range (1.0 × l0-11-1.0 × 10-6 M) with a slope of 20.5 ± 0.2 mV decade-1. The detection limit is 3.0 × 10-11 M while the sensor presents a response time of <10 s and a useful working pH range of 4.0-10.5. As a matter of fact, the proposed sensor discriminates relatively well the Lu (III) ions with regard to the common alkali, alkaline earth, heavy metals and, specially, lanthanide ions. It was successfully applied as an indicator electrode in a potentiometric titration of Lu (III) ions with EDTA. The proposed sensor was evaluated for the Lu (III) ions determination in some binary mixtures.

کلیدواژه ها:

Sub-nano molar ، PVC membrane ، micro-electrode ، Lu(III) oxicity ، Environmental pollutant