title: 175Yb-labeled hydroxyapatite: a potential agent for use in radiation synovectomy of small joints.
abstract: The preparation of 175Yb-labeled hydroxyapatite (HA) particle is described for possible use as an agent for radiation synovectomy (RS) of small-sized joints. 175Yb was produced by thermal neutron irradiation of enriched (98.6% in 174Yb) ytterbium target at a flux of approximately 3 x 10(13) n/cm(2)/s for 7 days. Specific activity of 5.5-6.0 GBq/mg and a very high radionuclidic purity to the extent of approximately 100% were obtained. In the work reported herein, HA could be labeled with 175Yb in very high radiochemical purity (>99%) using 10 mg of HA particle at pH approximately 7. The radiolabeled particulates showed excellent in vitro stability at room temperature. Serial scintigraphic images of normal as well as arthritis-bearing Wistar rats following intra-articular injection of 175Yb-HA particles in the knee joint showed complete retention of activity within the synovial cavity with no measurable activity leaching out from the joint till 144 h post-injection.
authors.affiliation: Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
authors.forename: Sudipta
authors.initials: S
authors.lastname: Chakraborty
authors.forename: Tapas
authors.initials: T
authors.lastname: Das
authors.forename: Sharmila
authors.initials: S
authors.lastname: Banerjee
authors.forename: Suresh
authors.initials: S
authors.lastname: Subramanian
authors.forename: Haladhar Dev
authors.initials: HD
authors.lastname: Sarma
authors.forename: Meera
authors.initials: M
authors.lastname: Venkatesh
mesh_terms: D000818:Animals; D017886:Durapatite / Q000737:chemistry / Q000493:pharmacokinetics* / Q000627:therapeutic use; D005240:Feasibility Studies; D007553:Isotope Labeling; D008297:Male; D008657:Metabolic Clearance Rate; D009928:Organ Specificity; D020370:Osteoarthritis, Knee / Q000378:metabolism* / Q000532:radiotherapy; D011868:Radioisotopes / Q000737:chemistry / Q000493:pharmacokinetics* / Q000627:therapeutic use; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000493:pharmacokinetics / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution; D015018:Ytterbium / Q000737:chemistry / Q000493:pharmacokinetics* / Q000627:therapeutic use
chemical_list: D011868:Radioisotopes; D019275:Radiopharmaceuticals; D017886:Durapatite; D015018:Ytterbium