title: High-yielding, automated production of 3'-deoxy-3'-[(18)F]fluorothymidine using a modified Bioscan Coincidence FDG reaction module.
abstract: BACKGROUND
  High-yielding, automated production of a PET tracer that reflects proliferation, 3'-deoxy-3'-[(18)F]fluorothymidine ([(18)F]FLT), is reported using a modified Bioscan Coincidence FDG reaction module.
  
  
  METHODS
  Production of [(18)F]FLT was implemented through: (1) modification of an original FDG manifold; (2) application of an alternate time sequence; and (3) altered solid-phase extraction (SPE) purification. Quality control testing, including standard radiochemical figures of merit and preclinical positron emission tomography (PET) imaging, was carried out.
  
  
  RESULTS
  High decay-corrected yields of [(18)F]FLT (16-39%) were reproducibly obtained. The product exhibited very high specific activity (4586.9TBq/mmol; 123,969Ci/mmol) and radiochemical purity (>99%). Overall, the [(18)F]FLT produced in this manner was superior to typical productions that utilized a GE TRACERlab FXF-N reaction module. Additionally, purification with SPE cartridges, followed by manual elution, accelerated overall run time and resulted in a two-fold increase in [(18)F]FLT concentration. PET imaging showed the [(18)F]FLT produced by this method was highly suitable for non-invasive tumor imaging in mice.
  
  
  CONCLUSIONS
  The Bioscan Coincidence GE FDG Reaction Module was readily adapted to reproducibly provide [(18)F]FLT in high yield, specific activity, and radiochemical purity. The approach was suitable to provide sufficient amounts of material for preclinical studies.
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University Medical Center, Nashville, TN, USA.
authors.forename: Yiu-Yin
authors.initials: YY
authors.lastname: Cheung
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University Medical Center, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Nickels
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA.
authors.forename: Eliot T
authors.initials: ET
authors.lastname: McKinley
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University Medical Center, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
authors.forename: Jason R
authors.initials: JR
authors.lastname: Buck
authors.affiliation: Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University Medical Center, Nashville, TN, USA; Program in Chemical and Physical Biology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA. Electronic address: henry.c.manning@vanderbilt.edu.
authors.forename: H Charles
authors.initials: HC
authors.lastname: Manning
mesh_terms: D000818:Animals; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging; D015224:Dideoxynucleosides / Q000138:chemical synthesis* / Q000592:standards; D045325:HCT116 Cells; D064593:Heterografts; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D049268:Positron-Emission Tomography / Q000379:methods*; D011786:Quality Control; D011854:Radiochemistry / Q000295:instrumentation / Q000379:methods; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000592:standards
chemical_list: D015224:Dideoxynucleosides; D019275:Radiopharmaceuticals; C002854:alovudine
keywords: Automated radiosynthesis; Positron emission tomography (PET); Solid-phase extraction (SPE); [(18)F]FLT