Particle sizing and biokinetics of interstitial lymphoscintigraphic agents.
The biokinetics of inert lymphoscintigraphic agents strongly depends on their particle size. Different techniques for characterization of colloids are discussed. Experiments have been performed on eight different colloids. The particle size has been investigated with scanning electron microscopy. Activity distributions have been obtained with ultrafiltration and gel-column scanning technique. The colloids suggested for lymphoscintigraphy were found to have a median size of about 40-50 nm except one minimicro-aggregated human serum albumin colloid which has a median particle size around 10 nm. The biokinetics were studied with a scintillation camera in rabbits after a subcutaneous injection. Time-activity curves were generated. After 5 hr the rabbits were dissected and the activity content in different tissues measured. A compartment model for the biokinetics was designed and rate constants evaluated. The total and specific activity uptake in parasternal lymph nodes was highest for the small-particle colloids. The compartment model showed a good fitting to the experimental data.
D000042:Absorption; D000818:Animals; D000965:Antimony; D003102:Colloids; D006801:Humans; D007700:Kinetics; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000378:metabolism; D010316:Particle Size; D010587:Phagocytosis; D011817:Rabbits; D011877:Radionuclide Imaging; D012211:Rhenium / Q000378:metabolism*; D012709:Serum Albumin / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*; D013667:Technetium / Q000378:metabolism*; D017556:Technetium Compounds; D013668:Technetium Tc 99m Aggregated Albumin; D013671:Technetium Tc 99m Sulfur Colloid; D014001:Tin / Q000378:metabolism*; D017971:Tin Compounds; D014018:Tissue Distribution
D003102:Colloids; D012709:Serum Albumin; D017556:Technetium Compounds; D013668:Technetium Tc 99m Aggregated Albumin; D017971:Tin Compounds; C019096:technetium Tc 99m antimony sulfide; C037609:technetium Tc 99m tin-sulfur colloid; C030406:technetium Tc rhenium-sulfur colloid; D013671:Technetium Tc 99m Sulfur Colloid; D013455:Sulfur; D012211:Rhenium; D013667:Technetium; D014001:Tin; D000965:Antimony