NCA (/sup 18/F)-16. cap alpha. -fluoroestradiol-17. beta. : Optimization of yield and quality control by HPLC

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:6793902

Brodack, J W; Kilbourn, M R; Welch, M J; Katzenellenbogen, J A

The authors have reported the synthesis and biodistribution of F-18-labeled ligands to the estrogen receptor with high radiochemical yields but low specific activity (166 Ci/mmol). Reduction of the amount of carrier fluoride resulted in significantly decreased radiochemical yields. The authors have therefore re-examined the parameters of the labeling reaction. Fluorine-18 from a (/sup 18/O)H/sub 2/O target cannot be used directly in this synthesis, all traces of water must be removed and the fluoride converted to its tetra -n-butylammonium salt. Initially the authors resolubilized fluorine ion into THF from a platinum crucible, which yields --50% of the activity for radiolabeling studies. In the synthesis of F-18-16..cap alpha..-fluoroestradiol-17..beta.., this resolubilized fluoride has given an overall average yield of 8% for the compound, or 16% based on the solubilized activity. Several other vessels were investigated to determine their effect on fluoride solubilization and overall yield of the fluorestradiol. Of these, resolubilization in a Vacutainer affords 93% of the activity in anhydrous THF, with a significant improvement in the overall yield of the fluorestradiol (22%) and its yield based on solubilized activity (27%) with a specific activity of 1600 Ci/mmol. The single column HPLC purification of the F-18 estrogen does not yield a product with >99% radiochemical purity; analyses of the purified product have shown up to approx. =9% of radiolabeled impurities. These results emphasize the need for additional quality control procedures to ensure desired purity of a compound that is to be used for in vivo studies.

• Research Organization: Washington Univ. School of Medicine, St. Louis, MO
• OSTI ID: 6793902
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400700 -- Radiochemistry & Nuclear Chemistry
550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CARRIERS
CHEMICAL PREPARATION
CHEMICAL REACTION YIELD
CHEMISTRY
CHROMATOGRAPHY
CONTROL
DILUTION
DISTRIBUTION
ESTRADIOL
ESTRANES
ESTROGENS
FLUORIDES
FLUORINE 18
FLUORINE COMPOUNDS
FLUORINE ISOTOPES
HALIDES
HALOGEN COMPOUNDS
HORMONES
HOURS LIVING RADIOISOTOPES
HYDROXY COMPOUNDS
IN VIVO
ISOTOPES
LABELLING
LIGANDS
LIGHT NUCLEI
MEMBRANE PROTEINS
NUCLEI
ODD-ODD NUCLEI
OPTIMIZATION
ORGANIC COMPOUNDS
PROTEINS
PURIFICATION
QUALITY CONTROL
RADIOACTIVITY
RADIOCHEMISTRY
RADIOISOTOPES
RADIONUCLIDE KINETICS
RECEPTORS
REMOVAL
SEPARATION PROCESSES
STEROID HORMONES
STEROIDS
SYNTHESIS
TISSUE DISTRIBUTION
WATER REMOVAL
YIELDS