Experimental and PM6/SPARKLE Semiempirical Study of Interaction between 4‐Methoxyphenylcyanamide and Gadolinium(III) as a Fast Polymeric Membrane Sensor

Abstract

In this study, a highly sensitive PVC-membrane sensor based on 4-methoxyphenylcyanamide (4-MeOpcyd) as a neutral carrier was prepared and the specific interaction between Gd 3 + ions and ionophore at the surface of selective polymeric membrane was calculated using the PM6/SPARKLE semiempirical method. The results of the Mopac2009 calculations show selective complexation of Gd 3 + by 4-MeOpcyd ligand that correlate quite well with experimental data. This membrane sensor has a linear response in the range of 1.0 10 À6 -1.0 10 À2 M Gd 3 + with detection limit of 6.2 10 À7 M. This electrode was applied in potentiometric titration for determination of gadolinium and also for fluoride ions in the mouthwash samples with satisfactory results.

Development of a highly efficient gadolinium(III) potentiometric sensor using two aza-crown ether-based multiple diglycolamides (DGAs)

“…The lower pH ensures the presence of gadolinium as Gd 3+ species in the solution which is required for sensing gadolinium ion by ISE. The selectivity coefficient determined by the present sensor for different mono-, divalent (Mg, Sr, Zn) ions are in the range of 10 − 2 to 10 − 4 which indicates poor interference of these metal ions in the determination of Gd 3+ and the values are comparable or better with those determined by Rezaei et al [64]. Although, the other…”

“…There are limited reports available on Gd 3+ potentiometric sensors in the literature. Among the reported results [6,17,[61][62][63][64][65], the present sensor membrane (M5, S.No.8) is found to be better suited to analyse Gd 3+ ion at lower concentrations than all the other reported membrane sensors except for that at S.No. 2 given in Table 4.…”

Sparkle/PM7 Lanthanide Parameters for the Modeling of Complexes and Materials

“…57 A recent thorough independent assessment of the Sparkle model accuracy has been recently published by Seitz and Alzakhem, 59 in which they calculated the geometries of over 650 lanthanide complexes with Ln−OH 2 motifs and found them, especially Sparkle/AM1, to be "surprisingly accurate for the estimation of the average bond lengths between the lanthanide ion and the water oxygen for the technologically important central lanthanides Eu(III), Gd(III), and Tb(III)". Indeed, since its conception, the Sparkle model has been successfully applied to several research problems, such as the study of energy transfer in Ir(III)/ Eu(III) dyads, 60 investigation of a Sm membrane sensor and membrane interfaces, 61−63 modeling metal organic frameworks, 63 chiral complexes, 65 Tb(III) light conversion molecular devices, 66 and a tetramer complex of Eu(III) containing 181 atoms 67 long-range interactions, resulting in a much improved prediction of crystal structures and heats of formation of solids. Indeed, PM7 contains improvements in the description of dispersion and hydrogen bonds which were incorporated into the method before the parametrization was carried out, to better describe noncovalent interactions.…”