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Introduction: The scope of using no carrier added (NCA) (90)Y [T(1/2) = 64.1 h, Eβ(max) = 2.28 MeV] obtained from (90)Sr/(90)Y generator in radiation synovectomy (RSV) is widely accepted. In the present study, the prospect of using (90)Y produced by (n,γ) route in a medium flux research reactor for use in RSV was explored., Methods: Yttrium-90 was produced by thermal neutron irradiation of Y(2)O(3) target at a neutron flux of ~1×10(14) n/cm(2).s for 14 d. The influence of various experimental parameters were systematically investigated and optimized to arrive at the most favorable conditions for the formulation of (90)Y labeled hydroxyapatite (HA) using HA particles of 1-10 μm size range. An optimized kit formulation strategy was developed for convenient one-step compounding of (90)Y-HA, which is easily adaptable at hospital radiopharmacy. The pre-clinical biological evaluation of (90)Y-HA particles was studied by carrying out biodistribution and bioluminiscence imaging studies in Wistar rats. The first clinical investigation using the radiolabeled preparation was performed on a patient suffering from chronic arthritis in knee joint by administering 185 MBq (90)Y-HA formulated at the hospital radiopharmacy deploying the proposed strategy., Results: Yttrium-90 was produced with a specific activity of 851 ± 111 MBq/mg and radionuclidic purity of 99.95 ± 0.02%. (90)Y-labeled HA particles (185 ± 10 MBq doses) were formulated in high radiochemical purity (>99%) and excellent in vitro stability. The preparation showed promising results in pre-clinical studies carried out in Wistar rats. The preliminary results of the first clinical investigation of (90)Y-HA preparation in a patient with rheumatoid arthritis in knee joints demonstrated the effectiveness of the formulation prepared using (90)Y produced via (n,γ) route in the management of the disease., Conclusion: The studies revealed that effective utilization of (90)Y produced via (n,γ) route in a medium flux research reactor coupled with the developed strategy of using HA kits for convenient formulation of (90)Y-HA at the hospital radiopharmacy can contribute to sustainable growth in the clinical utilization of (90)Y in RSV in the foreseeable future., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Aim: Integrin αvβ3 plays a significant role in angiogenesis during tumor growth and metastasis, and is a receptor for the extracellular matrix proteins with the exposed arginine(R)-glycine(G)-aspartic acid(D) tripeptide sequence. The over-expression of integrin αvβ3 during tumor growth and metastasis presents an interesting molecular target for both early detection and treatment of rapidly growing solid tumors. Considering the advantages of (177)Lu for targeted radiotherapy and enhanced tumor targeting capability of cyclic RGD peptide dimer, an attempt has been made to optimize the protocol for the preparation of clinical dose of (177)Lu labeled DOTA-E[c(RGDfK)]2 (E=Glutamic acid, f=phenyl alanine, K=lysine) as a potential agent for targeted tumor therapy., Methods: (177)Lu was produced by thermal neutron bombardment on enriched Lu2O3 (82% in (176)Lu) target at a flux of 1 × 10(14) n/cm(2).s for 21 d. Therapeutic dose of (177)Lu-DOTA-E[c(RGDfK)]2 (7.4GBq) was prepared by adding the aqueous solution of the ligand and (177)LuCl3 to 0.1M NH4OAC buffer containing gentisic acid and incubating the reaction mixture at 90°C for 30 min. The yield and radiochemical purity of the complex was determined by HPLC technique. Parameters, such as, ligand-to-metal ratio, pH of the reaction mixture, incubation time and temperature were varied using tracer quantity of (177)Lu (37 MBq) in order to arrive at the optimized protocol for the preparation of clinical dose. Biological behavior of the radiotracer prepared was studied in C57/BL6 mice bearing melanoma tumors., Results: (177)Lu was produced with a specific activity of 950 ± 50 GBq/mg (25.7 ± 1.4 Ci/mg) and radionuclidic purity of 99.98%. A careful optimization of several parameters showed that (177)Lu-DOTA-E[c(RGDfK)]2 could be prepared with adequately high radiochemical purity using a ligand-to-metal ratio ~2. Based on these studies therapeutic dose of the agent with 7.4 GBq of (177)Lu was formulated in ~63 GBq/μM specific activity with high yield (98.2 ± 0.7%), radiochemical purity and in vitro stability. Biodistribution studies carried out in C57/BL6 mice bearing melanoma tumors revealed specific accumulation of the radiolabeled conjugate in tumor (3.80 ± 0.55% ID/g at 30 min p.i.) with high tumor to blood and tumor to muscle ratios. However, the uptake of the radiotracer in the tumor was found to be reduced to 1.51 ± 0.32 %ID/g at 72 h p.i., Conclusions: The present work successfully demonstrates the formulation of an optimized protocol for the preparation of (177)Lu labeled DOTA-E[c(RGDfK)]2 for PRRT applications using (177)Lu produced by direct neutron activation in a medium flux research reactor., (Copyright © 2013 Elsevier Inc. All rights reserved.)

A method for the separation of no-carrier-added (nca) arsenic radionuclides from bulk amounts of irradiated germanium oxide (GeO2) target was developed in view of their potentialities in different biological and nuclear medicine applications. The beta- emitting 77As radionuclide, produced by the decay of 77Ge through the natGe(n,gamma)77Ge nuclear reaction, was used for standardization of the radiochemical separation procedure. The radiochemical separation was performed by precipitation followed by solvent extraction. About 99% post-irradiation recovery of the GeO2 target material, in a form suitable for reuse in future irradiation, was achieved. The developed method was suitable for the production of nca arsenic radionuclides either as trivalent or pentavalent arsenic in various vehicles which provided flexibility of formulations of different kinds of compound. The overall radiochemical yield for the complete separation of 77As was 90%. The separated nca 77As was of high radionuclidic purity and did not contain detectable amounts of the target material. This method can be adopted for the radiochemical separation of other different arsenic radionuclides produced from GeO2 through cyclotron as well as reactor irradiation.