|
|
Eur. J. Mass Spectrom.
9, 129–137 (2003)
DOI:
10.1255/ejms.529 |
|
Atmospheric pressure electrospray ionization mass spectra of glucose and 2-fluorodeoxyglucose for quantitative analysis of 2-fluorodeoxyglucose
by high-performance liquid chromatography |
|
F. Macášek,* P. Brúder and A. Patakyová Department of
Nuclear Chemistry, Faculty of Natural Sciences, Comenius University, SK-84215 Bratislava, Slovakia. E-mail: macasek@fns.uniba.skE.
BúriováSlovak Office of Standards, Metrology and Testing, Cyclotron Section, Stefanovicova 3, PO Box 76, SK-81005 Bratislava, Slovakia |
| ABSTRACT: |
|
2-Fluoro-
2-deoxy-D-glucose (FDG) labeled by fluorine-18 is the most widely used radiopharmaceutical for positron emission tomography (PET). For high-performance liquid
chromatography (HPLC)/MS assay and quality control, the mass spectra of FDG and glucose (Glc) in organic + water solutions were studied by flow injection analysis (FIA) and in
a chromatographic eluate. In acetonitrile (MeCN) + 0.025% ammonium formate (NH4HCO2) solvent (80 : 20), electrospray ionisation (ESI) of glucose-
FDG provides M.NH4+ and 2M.Na+ (M = Glc or FDG) as the most intense positive ions. Formation of the latter ions and also of
M.MeCN.Na+ and 2MeCN.Na+ is typical of the presence of NaCl in the ESI inlet. The positive ions include heavier ions corresponding to the impurities
separated by HPLC and also to the cross-ring fragmentation of complexes (2FDG. aMeCN–X)L, where a = 0 or 1, L is either Na+ or
NH4+ and X is a fragmented pyranose or anhydropyranose residue. The second most abundant Glc negative ion is m/z = 359 which was
interpreted as (2Glc–H+)–. The negative-ion spectrum of FDG has dominating lines due to FDG.HCO2– ions
at m/z 227 and also (2FDG–H+)– at m/z 363. The m/z 363 signal is suppressed in the presence of NaCl at a molar ratio
of 4 : 1 to NH4HCO2, while the ions at m/z 217 and 219, i.e. FDG.Cl–, become three times more intense than
FDG.HCO2–. The latter ion appears to be most suitable as an analytical signal for chemical analysis of FDG at m/z 226 and 227. Limits of
FDG quantitation (LOQ) of 19 ng and 21 ng were found for the 200+ and 227– ion signals, respectively, and are wholly adequate for verification of
total FDG content in radiopharmaceuticals. |
|
Keywords:
electrospray ionization, high-performance liquid chromatography, LC/MS analysis, saccharides, glucose, fluorodeoxyglucose, FDG,
radiopharmaceuticals |
