Preparation and characterization of a novel optical chemical sensor for determination of trace amounts of Praseodymium ion by UV/Vis spectrophotometry

Abstract

In the present work, a novel optical chemical sensor (optode) was prepared based on impregnation of N, Ń-bis (salicylidene)-1, 3-ethylenediamine (BESA) Schiff base into mesoprous SBA-15 paste for determination of trace amounts of Praseodymium (Pr) ion by UV/Vis spectrophotometry. The sensor was fabricated by dip-coating triacetylcellulose membrane into indicator solution. The proposed optical sensor was prepared through a routine procedure and characterized by various techniques such as ATR-FT-IR and SEM analyses. This optode exhibited a linear range of 10 to 190ngmL−1 for Pr(III) ion concentration with a detection limit of 5.0ngmL−1. The value of the response time for the newly synthesized optode was within 100s while depending on the Pr(III) ion concentration. The proposed optode showed low detection limit, fast response time and high selectivity with respect to the group of transition metal ions (Ce3+, Nb3+, La3+, Cr3+, Zn2+, Hg2+, and Fe2+ ions). The optode was successfully regenerated with a mixture of thiourea and NaOH solution and the response was reversible with the relative standard deviation (R.S.D.) of 1.6%. The optode was stable and stored for at least 17days without any considerable change in its sensitivity. Finally, the developed optode was applied to determine the Pr(III) ions in spiked samples.