Pre vivo, ex vivo and in vivo evaluations of [68Ga]-EDTMP.
BACKGROUND
The objectives of this study were to develop a simple preparation method for [68Ga]-EDTMP and to evaluate the applicability of [68Ga]-EDTMP as a potential positron emission tomography (PET) bone imaging agent using pre vivo, ex vivo and in vivo models.


METHODS
[68Ga]-EDTMP was prepared using 68Ga]-gallium chloride eluted from the 68Ge/68Ga generator and commercially available Multibone kits. Binding affinity to bone compartments was evaluated using a recently established pre vivo model. In vivo (microPET) and ex vivo experiments were performed in mice, and the results of which were compared with those obtained with [18F]-fluoride.


RESULTS
[68Ga]-EDTMP was accessible via simple kit preparation and predominantly accumulated in bone tissue in vivo, ex vivo and pre vivo. Binding to mineral bone was irreversible, and low binding was observed in organic bone. In vivo microPET evaluation revealed predominant uptake in bone with renal excretion. Compared with [18F]-fluoride, the uptake was lower and the PET image quality was reduced.


CONCLUSIONS
From the present evaluation, apart from the autonomy for PET centers without an onsite cyclotron, the advantage of [68Ga]-EDTMP over [18F]-fluoride is not apparent and the future clinical prospect of [68Ga]-EDTMP remains speculative.
Mitterhauser
Markus
M
Department of Nuclear Medicine, Medical University of Vienna, Vienna 1090, Austria. markus.mitterhauser@meduniwein.ac.at
Toegel
Stefan
S
Wadsak
Wolfgang
W
Lanzenberger
Rupert R
RR
Mien
Leonhard-Key
LK
Kuntner
Claudia
C
Wanek
Thomas
T
Eidherr
Harald
H
Ettlinger
Dagmar E
DE
Viernstein
Helmut
H
Kluger
Rainer
R
Dudczak
Robert
R
Kletter
Kurt
K
D000818:Animals; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D005462:Fluorine Radioisotopes / Q000493:pharmacokinetics; D005710:Gallium Radioisotopes / Q000737:chemistry; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007202:Indicators and Reagents; D051379:Mice; D009943:Organophosphorus Compounds / Q000493:pharmacokinetics*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D014018:Tissue Distribution
D005462:Fluorine Radioisotopes; D005710:Gallium Radioisotopes; D007202:Indicators and Reagents; D009943:Organophosphorus Compounds; D019275:Radiopharmaceuticals; C018940:(ethylenedinitrilo)-tetramethylenephosphonic acid