Planar chromatographic analysis and quantification of short-lived radioactive metabolites from microdialysis fractions.
A sensitive radiochromatographic method for the quantitative determination of compounds labelled with short-lived beta-emitting radionuclides in microdialysates is described. The method is well suited for microdialysis (MD) samples, which have small volumes and low concentrations of compounds. An 18F-labelled (beta+; T(1/2)=109.8 min) radiopharmaceutical, (1R,2S)-4-[18F]fluorometaraminol (FMR), was injected intravenously into rats, and microdialysis fractions were then collected from the blood at 15 min intervals. Fractions were analyzed for FMR and its radioactive metabolites by planar chromatography combined with digital photostimulated luminescence autoradiography. The lowest detectable 18F-radioactivity was 0.24 Bq/application and the limit of quantification was 0.31 Bq/application with 4-16 h exposure. The method was found to be highly sensitive and linear in the range of 0.1 Bq-2 kBq. This method thus allows the quantification of beta-emitting radiopharmaceuticals in sequential microdialysis fractions with good time-resolution.
Haaparanta
Merja
M
Turku PET Centre, Medicity Research Laboratory/PET Preclinical Imaging, Tykistokatu 6A, FI 20520 Turku, Finland. merja.haaparanta-solin@utu.fi
Grönroos
Tove
T
Eskola
Olli
O
Bergman
Jörgen
J
Solin
Olof
O
D000818:Animals; D001345:Autoradiography; D002855:Chromatography, Thin Layer / Q000379:methods*; D005462:Fluorine Radioisotopes; D008680:Metaraminol / Q000031:analogs & derivatives* / Q000097:blood; D017551:Microdialysis; D051381:Rats; D012680:Sensitivity and Specificity
C413488:4-fluorometaraminol; D005462:Fluorine Radioisotopes; D008680:Metaraminol