title: New bis(azobenzocrown)s with dodecylmethylmalonyl linkers as ionophores for sodium selective potentiometric sensors.
abstract: Novel biscrowns1and2were synthesized from 13-membered azobenzocrown ethers containing bromoalkylenoxy chains inparaposition relative to the azo group. The synthesized diester molecules are dodecylmethylmalonic acid derivatives differing by the linker length. The synthesized compounds have the potential of being used as sodium ionophores in ion-selective electrodes. They were characterized and used as ionophores in classic and miniature,solid contact(screen-printed and glassy carbon) membrane ion-selective electrodes. Compound3, a similar monoester derivative of 13-membered azobenzocrown, was synthesized and used in membrane electrodes for comparison. Lipophilicity of new ionophores was determined by TLC. Lipophilicity of bis(azobenzocrown)s was found to be within the range of logPTLC= 12-13. It was observed that the particularly important selectivity coefficients logKNa,Kdetermined for new electrodes, being logKNa,K= -2.5 and -2.6 (SSM, 0.1 M), are better than those of the electrodes featuring seven out of the nine commercially available sodium ionophores. It was concluded that the ionophore1creates, in acetone, with sodium iodide, complex of 1:1 stoichiometry (sandwich complex) with stability constant (logK) ca. 3.0.
authors.affiliation: Department of Chemistry and Technology of Functional Materials, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Luboch
authors.affiliation: Department of Chemistry and Technology of Functional Materials, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Jeszke
authors.affiliation: Department of Chemistry and Technology of Functional Materials, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland.
authors.forename: Mirosław
authors.initials: M
authors.lastname: Szarmach
authors.affiliation: Department of Chemistry and Technology of Functional Materials, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Łukasik
keywords: Bis(azobenzocrown)s; Ion-selective electrodes; Sodium ionophores; Solid contact electrodes; Synthesis