title: Development of an electrochemical 90 Sr-90 Y generator for separation of 90 Y suitable for targeted therapy.
abstract: 90 Y of high specific activity and very high radionuclidic purity (>99.998%) is essential for targeted therapy. Since the current methods used for the preparation of 90 Y from 90 Sr are not adaptable for use in a central/hospital radiopharmacy, a simple 90 Sr-90 Y generator system based on electrochemical separation technique was developed.
  
  
  METHODS
  Two-cycle electrolysis procedure was developed for separation of 90 Y from 90 Sr in nitrate solution. The first electrolysis was performed for 90 min in 90 Sr(NO3)2 feed solution at pH 2-3 at a potential of -2.5 V with 100-200 mA current using platinum electrodes. The second electrolysis was performed for 45 min in 3 mM HNO3 at a potential of -2.5 V with 100 mA current. In this step, the cathode from the first electrolysis containing 90 Y was used as anode along with a fresh circular platinum electrode as cathode. The 90 Y deposited on the circular cathode after the second electrolysis was dissolved in acetate buffer to obtain 90 Y acetate, suitable for radiolabeling.
  
  
  RESULTS
  >96% recovery of 90 Y could be achieved in each cycle, with an overall decay corrected yield of >90%. The recovered 90 Y had high radionuclidic purity with barely 30.2+/-15.2 kBq (817+/-411 nCi) of 90 Sr per 37 GBq (1 Ci) of 90 Y (0.817+/-0.411 ppm). Consistent and repeated separation could be demonstrated using up to 1.85 GBq (50 mCi) of 90 Sr. The generator was named "Kamadhenu," the eternally milk-yielding Indian mythological cow.
  
  
  CONCLUSIONS
  A technique suitable for adaptation at central radiopharmacies for obtaining therapeutic quantities of pure 90 Y has been developed.
authors.affiliation: Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai-400085, India.
authors.forename: Rubel
authors.initials: R
authors.lastname: Chakravarty
authors.forename: Usha
authors.initials: U
authors.lastname: Pandey
authors.forename: Remani B
authors.initials: RB
authors.lastname: Manolkar
authors.forename: Ashutosh
authors.initials: A
authors.lastname: Dash
authors.forename: Meera
authors.initials: M
authors.lastname: Venkatesh
authors.forename: M R Ambikalmajan
authors.initials: MR
authors.lastname: Pillai
mesh_terms: D005591:Chemical Fractionation / Q000379:methods; D004566:Electrodes; D004572:Electrolysis / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design / Q000295:instrumentation*; D019999:Pharmaceutical Solutions / Q000032:analysis / Q000737:chemistry; D013326:Strontium Radioisotopes / Q000032:analysis / Q000737:chemistry*; D015021:Yttrium Radioisotopes / Q000032:analysis / Q000737:chemistry*
chemical_list: D019999:Pharmaceutical Solutions; D013326:Strontium Radioisotopes; D015021:Yttrium Radioisotopes