A novel PVC-membrane optical sensor for highly sensitive and selective determination of UO2(2+) ion based on a recently synthesized benzo-substituted macrocyclic diamide and dibenzoylmethane.

A highly sensitive ion-selective bulk optode membrane for sensing UO2(2+) ion based on plasticized poly(vinyl chloride) containing 6,7,9,10,12,13,15,16,23,24,25,26-dodecahydrodibenzo[n,v][1,4,7,10,13,17,20]pentaoxa-diazacyclotricosine-22,27-dione as ionophore, dibenzodylmethane as chromoionophore and sodium tetraphenylborate as an ionic additive was prepared. In addition to its high stability, reproducibility and relatively long lifetime, the proposed optical sensor revealed good selectivity for uranyl ion over a large number of alkali, alkaline earth, transition, and heavy metal ions. The proposed sensor displays a calibration response for UO2(2+) over a concentration range of 4.3 x 10(-6) to 2.5 x 10(-8) M with a limit of detection of 8.0 x 10(-9) M and a response time of less than 12 min. The proposed optical sensor was applied successfully to the determination of UO2(2+) ion in tap water and Khoshumi mine concentrated solution samples.