title: Use of liposomes as carriers for radiation synovectomy.
abstract: Using [99mTc]pertechnetate as an aqueous space marker, the permeability of liposomes composed of seven different mixtures of distearoylphosphatidylcholine (DSPC) and sphingomyelin (SM) was determined. Liposomes containing 20-33% SM were the least permeable in the presence of rheumatoid synovial fluid. Following injection of 99mTc-containing liposomes into the knee joints of rabbits, retention of 99mTc in the knee was more than 200 times greater than following injection of nonencapsulated [99mTc]pertechnetate. The knee clearance biologic half time of 99mTc with DSPC/SM (4:1) liposomes was 64 h. Most of the activity that had leaked from the knee was not found in extra-articular tissues, suggesting rapid excretion. When DSPC/SM (4:1) liposomes were labeled with 111In(oxine), a knee clearance biologic half time of greater than 1200 h was observed.
authors.affiliation: Department of Radiology (Nuclear Medicine), Harvard Medical School, Boston, MA 02115.
authors.forename: M R
authors.initials: MR
authors.lastname: Zalutsky
authors.forename: M A
authors.initials: MA
authors.lastname: Noska
authors.forename: P W
authors.initials: PW
authors.lastname: Gallagher
authors.forename: S
authors.initials: S
authors.lastname: Shortkroff
authors.forename: C B
authors.initials: CB
authors.lastname: Sledge
mesh_terms: D000818:Animals; D007205:Indium Radioisotopes; D008081:Liposomes / Q000008:administration & dosage*; D009942:Organometallic Compounds / Q000627:therapeutic use; D015125:Oxyquinoline / Q000031:analogs & derivatives / Q000627:therapeutic use; D010539:Permeability; D010713:Phosphatidylcholines; D011817:Rabbits; D013670:Sodium Pertechnetate Tc 99m / Q000493:pharmacokinetics / Q000627:therapeutic use*; D013109:Sphingomyelins; D013583:Synovial Membrane / Q000528:radiation effects*; D014018:Tissue Distribution
chemical_list: D007205:Indium Radioisotopes; D008081:Liposomes; D009942:Organometallic Compounds; D010713:Phosphatidylcholines; D013109:Sphingomyelins; C032950:indium oxine; D015125:Oxyquinoline; D013670:Sodium Pertechnetate Tc 99m; C010942:1,2-distearoyllecithin