title: An optimised radiolabel procedure to prepare (99m)Tc-colloidal rhenium sulphide to improve radiochemical purity.
abstract: BACKGROUND
  More than 25% of 99mTc colloidal rhenium sulphide preparations have been reported to have a radiochemical purity of <95% in 11 radiopharmacies.
  
  
  OBJECTIVE
  To identify the key parameters involved in radiochemical purity, different preparation procedures were analysed to develop an optimised preparation method.
  
  
  METHODS
  In the first part of this study, various data such as the Nanocis kit batch number, the eluate volume, the time between the two final elutions, the temperature and duration of heating were collected and analysed to determine the critical parameters that significantly decrease radiochemical purity. In the second part, a new procedure was applied and then the same parameters and radiochemical purity values were collected and compared with the results before the new procedure.
  
  
  RESULTS
  Among 184 preparations, 137 (75%) had a radiochemical purity exceeding 95%, 25 (13.6%) were between 90 and 95% pure and 22 (12%) were below 90%. Significantly higher radiochemical purity was observed after the implementation of the new preparation procedure (89.5% of 374 preparations had radiochemical purities of > 95%). This new procedure consists in lowering the 99mTc eluate volume and time of heating.
  
  
  CONCLUSIONS
  The implementation of a new method for the preparation of (99m)Tc colloidal rhenium sulphide based on a comparison of practices in various radiopharmacies resulted in: i) a determination of the critical points of this preparation, ii) an optimised labelling technique to harmonise different practices, and iii) a significant improvement in the preparations radiochemical purity and the quality of the lymphoscintigraphy in the location of sentinel node.
authors.affiliation: Radiopharmacy Units, Departments of Pharmacy, Lariboisière, France. benoit.hosten@lrb.aphp.fr
authors.forename: Benoît
authors.initials: B
authors.lastname: Hosten
authors.forename: Romain
authors.initials: R
authors.lastname: Roche
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Barre
authors.forename: Julien
authors.initials: J
authors.lastname: Fouque
authors.forename: Yvan
authors.initials: Y
authors.lastname: Mouraeff
authors.forename: Agnes
authors.initials: A
authors.lastname: Dumont
authors.forename: Catherine L E
authors.initials: CL
authors.lastname: Meur
authors.forename: Helene
authors.initials: H
authors.lastname: Garrigue
authors.forename: Sabrina
authors.initials: S
authors.lastname: Hassoun
authors.forename: Valerie
authors.initials: V
authors.lastname: Nataf
authors.forename: Corinne
authors.initials: C
authors.lastname: Smadja
authors.forename: Virginie
authors.initials: V
authors.lastname: de Beco
authors.forename: Karine
authors.initials: K
authors.lastname: Felice
authors.forename: Nathalie
authors.initials: N
authors.lastname: Rizzo-Padoin
mesh_terms: D002712:Chlorides / Q000737:chemistry*; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D019275:Radiopharmaceuticals / Q000737:chemistry*; D012211:Rhenium / Q000737:chemistry*; D013440:Sulfides; D013671:Technetium Tc 99m Sulfur Colloid / Q000737:chemistry*
chemical_list: D002712:Chlorides; D019275:Radiopharmaceuticals; D013440:Sulfides; C400124:rhenium sulfide; D013671:Technetium Tc 99m Sulfur Colloid; D012211:Rhenium