Gallium-68 chemistry for labeling platelets, proteins and lipoproteins

Conference · Sun Jul 01 04:00:00 EDT 1984

OSTI ID:5934298

Yano, Y; Budinger, T F; Ebbe, S N; Mathis, C A; Moore, D H; Singh, M; Brennan, K; Moyer, B R; Nichols, A

Generator produced gallium-68 is a convenient useful radionuclide for positron emission tomography (PET) investigations. Gallium-68 labeled platelets and low density lipoproteins would be useful agents for PET studies of thrombosis and atherosclerosis in cardiovascular disease. To label these agents with Ga-68, we have studied the effects of trace metal contaminants in 1 N HCl elutions of Ga-68 from germanium-68 absorbed on a stannic oxide column. Studies were conducted on the formation and characteristics of Ga-68 complexes with the ligands 8-hydroxyquinoline, tropolone, and mercaptopyridine-N-oxide (MPO). Various parameters such as pH, buffers, concentration of ligand, and incubation or stability with time were investigated. High performance liquid chromatography and instant thin layer chromatography were used to analyze the Ga-68 ligand preparations. Platelets separated from human, dog, and rabbit plasma were incubated with the Ga-68 complexes and the labeling yields and in vivo survival were determined. The accumulation of the platelets in the ballon catheter scraped aorta of the rabbit was determined by PET imaging studies, tissue counting in a gamma well counter, and en-face autoradiography of the arterial wall. The Ga-68 complexes of MPO gave 40 to 60% labeling efficiency of rabbit platelets which accumulated about fourfold more in the damaged aorta compared to the normal. Gallium-68 was attached to low density lipoproteins (LDL) with the bifunctional chelate of DTPA. Low pressure gel column chromatography and HPLC were used to preparatively separate and analyze the Ga-68 LDL for uptake studies in the healing endothelium of the scraped aorta rabbit model. The Ga-68 LDL labeling yield was 80 to 85% with a radiochemical purity 90 to 95%. 22 references, 10 figures, 4 tables.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5934298
• Report Number(s): LBL-18388; CONF-8407111-1; ON: DE85007227
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BLOOD PLATELETS
BODY FLUIDS
COMPLEXES
COMPUTERIZED TOMOGRAPHY
DATA
DIAGNOSTIC TECHNIQUES
DIAGNOSTIC USES
DOGS
EFFICIENCY
EMISSION COMPUTED TOMOGRAPHY
EXPERIMENTAL DATA
GALLIUM 68
GALLIUM ISOTOPES
HOURS LIVING RADIOISOTOPES
INFORMATION
INTERMEDIATE MASS NUCLEI
ISOTOPES
LABELLING
LIGANDS
MAMMALS
MAN
MATERIALS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
POSITRON COMPUTED TOMOGRAPHY
PRIMATES
RABBITS
RADIOISOTOPES
TOMOGRAPHY
USES
VERTEBRATES