In this work we explore the possibility of using anti-crown ether (C6HgF4)3 as a membrane-active component for potentiometric cross-sensitive sensors. Anti-crown ligands were already employed as ionophores in plasticized polymeric membranes, however the results of these studies are contradictory. In [1] mercury-carborundum-3 was employed to construct a chloride-selective sensor, while in [2] another anti-crown ligand was reported to be selective towards tetramethyl amine cations. At the same time some recent studies have explored the interaction between three-mercury anticrown ethers and anions and reported on formation of sandwich-type complexes [3].
In order to clarify the electrochemical sensitivity patterns of anti-crown based sensors we have studied plasticized polymeric membranes containing cation and anion-exchanging additives and various solvents-plasticizers. We explored the electrochemical sensitivity of these membranes in a wide variety of aqueous solutions of inorganic salts. Alkaline, alkaline-earth and d-elements salts with different anions were studied. It was found that the sensors based on anti-crown (C6HgF4)3 exhibit cationic sensitivity and no considerable anionic responses were observed. The highest sensitivity values were obtained for Cs+ (51 mV/dec) among single-charged cations, and for Pb2+ (19 mV/dec) among double-charged cations. No sharp selectivity towards particular cations was found. These features can be successfully employed in construction of cross-sensitive polymeric sensors for developing novel multisensor arrays.
References
1. Ibrahim H.A.Badr, Martin Diaz, M. Frederick Hawthorne, Leonidas G. Bachas.//Anal. Chem., v.71, p.1371-1374 (1999).
2. Zhenning Yan, Zhixian Zhou, Yanglie Wu, Shur, V. B.,Tikhonova, I. A.,// Analytical Letters, v.38, p.377-383 (2005).
3. K.I. Tugashov, D.A. Gribanyov, F.M. Dolgushin, A.F. Smol’yakov, A.S. Peregudov, M.Kh. Minacheva, L.A. Tikhonova, V.B. Shur // Organometallics, v.35, p.2197 (2016).
