Optical Chemical Sensor of Lutetium(III) in Water Based On 2-Nitro-6-(thiazol-2-yldiazenyl)phenol Immobilized on Polymethyl meth-acrylate and 2-Nitrophenyl octyl ether Matrix

Abstract

An optical chemical sensor membrane obtained by physical inclusion of a 2-nitro-6-(thiazol-2-yl-diazenyl)phenol (NTDP) as a selectophore and polymethyl methacrylate (PMMA) and 2-nitrophenyl octyl ether (NPOE) as a plasticizer. Methods: The adsorption of Lu(III) causes the colour of the membrane to change from orange to pink with maximum absorbance (λmax) at 606 nm. The sensor membrane gives the best response towards Lu(III) ion at pH 6.5, after 10 min of contact time, at 150 ng mL–1 Lu(III), and 10 mL solution. Results: A linear Lu(III) calibration curve can be developed in the concentration range of 5.0–280 ng mL–1 with R2 = 0.9990. The molar absorptivity is found to be 9.06 x 106 L mol–1 cm–1. The detection and of quantification limits are found to be 1.63 and 4.95 ng mL–1, respectively. Conclusion: The optical sensor membrane analytical characteristics was performed as interference of anions and cations, equilibrated time, reusability, detection limit, etc. and compared with the previous different conventional methods for Lu(III) using various chromophores. The optical sensor membrane investigated in this work was examined in real samples with excellent results comparing with the previous ICP-OES method.