Stabilities of lanthanide-protein complexes.
After incubation of both serum and HSA solutions with radioactive lanthanide complexes the binding constants of the corresponding lanthanide-protein complexes formed in the protein solutions under physiologic conditions, pH: 7.4, temperature: 310 K, isotonic ionic strength: 0.15 mol/L, were determined. The association constants of the lanthanide-protein complexes formed both in serum and HSA-solutions are equal within the experimental error. In conclusion, serum albumin binding predominates for the radiolanthanides. With the decrease of the ionic radii from 1.034 A (Ce) to 0.858 (Yb) the association constants increased by five orders of magnitude from 1 g Kpr = 4.90 (Ce) to 1 g Kpr = 9.54 (Yb). Further, a serum fractionation with alcohol was carried out to prove that the albumin fraction of serum is responsible for the lanthanide binding in blood.
Schomäcker
K
K
Central Institute of Nuclear Research, Dresden, G.D.R.
Mocker
D
D
Münze
R
R
Beyer
G J
GJ
D001798:Blood Proteins; D004355:Drug Stability; D006801:Humans; D008674:Metals, Rare Earth; D011485:Protein Binding; D012709:Serum Albumin
D001798:Blood Proteins; D008674:Metals, Rare Earth; D012709:Serum Albumin