Preparation and Evaluation of (68)Ga-ECC as a PET Renal Imaging Agent.
OBJECTIVE
Development of a gallium-68-labeled renal tracer can be a good substitute for Tc-99m, a known SPECT tracer. In this study, effort was made to develop (68)Ga-ethylenecysteamine cysteine ((68)Ga-ECC).


METHODS
Ga-ECC was prepared using generator-based (68)GaCl3 and ethylenecysteamine cysteine (ECC) at optimized conditions. Stability of the complex was checked in human serum followed by partition coefficient determination of the tracer. The biodistribution of the tracer in rats was studied using tissue counting and PET/CT imaging up to 120 min.


RESULTS
Ga-ECC was prepared at optimized conditions in 15 min at 90 °C (radiochemical purity ≈97 ± 0.88 % ITLC, >99 % HPLC, specific activity: 210 ± 5 GBq/mM). (68)Ga-ECC was a water-soluble complex based on partition coefficient data (log P; -1.378) and was stable in the presence of human serum for 2 h at 37 °C. The biodistribution of the tracer demonstrated high kidney excretion of the tracer in 10-20 min. The SUVmax ratios of the liver to left kidney were 0.38 and 0.39 for 30 and 90 min, respectively, indicating high kidney uptake.


CONCLUSIONS
Initial biodistribution results showed significant kidney and urinary excretion of the tracer comparable to that of the homologous (99m)Tc compound. The complex could be a possible PET kidney imaging agent with a fast imaging time.
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Alireza
A
Mirzaei
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Amir Reza
AR
Jalilian
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Ayuob
A
Aghanejad
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Mohammad
M
Mazidi
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Hassan
H
Yousefnia
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Gholamali
G
Shabani
Radiation Application Research School, Nuclear Science and Technology Research Institute, Postal code: 141551339 Tehran, Iran.
Khosro
K
Ardaneh
Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Parham
P
Geramifar
Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Davood
D
Beiki
68Ga; Biodistribution; Ethylenecysteamine cysteine; PET/CT; Renal agent