FORMATION AND STABILITY OF LANTHANIDE COMPLEXES AND THEIR ENCAPSULATION INTO POLYMERIC MICROSPHERES

Mumper, RJ; Jay, M

HERO ID

1965772

Reference Type

Journal Article

Year

1992

HERO ID 1965772
In Press No
Year 1992
Title FORMATION AND STABILITY OF LANTHANIDE COMPLEXES AND THEIR ENCAPSULATION INTO POLYMERIC MICROSPHERES
Authors Mumper, RJ; Jay, M
Volume 96
Issue 21
Page Numbers 8626-8631
Abstract The complexation of lanthanides (Ln) with dicarbonyl compounds (acetylacetone, acac; ethyl acetoacetate; 3-ethyl-2,4-pentanedione; 2,4-hexanedione; 3-methyl-2,4-pentanedione; and diethyl malonate) was investigated using a potentiometric titration technique. The ability of a dicarbonyl compound to complex with the lanthanide elements was greatly dependent on its pK(a) and on the pH of the titrated solution. Selected lanthanide complexes (Ln complexes) were incorporated into spherical poly(L-lactic acid) (PLA) matrices and irradiated in a nuclear reactor with neutrons to produce short-lived high-energy beta-particle-emitting radioisotopes. The lanthanides investigated (Ho, Dy, Sm, and La) were chosen on the basis of their physical and nuclear properties. A transition element (Re) was also studied. The small decrease in the ionic radii of the lanthanides with increasing atomic number led to (a) greater ability to extract and complex from an aqueous solution with complexing agents, (b) larger formation and stability constants for the Ln complexes, (c) increased solubility of the Ln complexes in chloroform, and (d) increase in the maximum percent incorporation of the stable lanthanides in PLA spheres. Ho(acaC)3 was found to be the most promising candidate of the complexes studied on the basis of the above observations and due to the favorable physical properties of Ho-165 and nuclear properties of Ho-166.
Wosid WOS:A1992JU55500076
Is Certified Translation No
Dupe Override No
Comments Journal:JOURNAL OF PHYSICAL CHEMISTRY 0022-3654
Is Public Yes