Development of a novel PVC-membrane fluorescent sensor based on N,N'-bis(dansylamidoethyl)-N,N'-bis(2-pyridylmethyl)propylenediamine as a new fluoroionophore for highly sensitive and selective monitoring of trace amounts of La3+ ions in aqueous solutions

A new fluorescent sensor for the highly sensitive and selective determination of La3+ion isdeveloped. The sensing membrane was prepared by incorporating N,N-bis(dansylamidoethyl)-N,N-bis(2-pyridylmethyl)propylenediamine (L) as fluoroionophore in the plasticized PVC membranecontaining o-NPOE as plasticizer. The proposed sensor displays a wide calibration range of 5.0 × 10−9to 5.0 × 10−4M with a low limit of detection of 2.0 × 10−9M in a solution of pH 6.0. This sensor hasa relatively fast response time of less than 2 min. In addition to high stability and reproducibility, itshows a unique selectivity toward La3+ion with respect to common coexisting cations. The sensor canbe regenerated by exposure to a solution of EDTA. The proposed sensor was successfully applied to thedetermination of La3+ in aqueous solutions.