Rapid Synthesis of Ga-labeled macroaggregated human serum albumin (MAA) for routine application in perfusion imaging using PET/CT.

Tc-labeled MAA is commonly used for single photon emission computed tomography SPECT. In contrast, positron emission tomography/CT (PET/CT) delivers images with significantly higher resolution. The generator produced radionuclide Ga is widely used for PET/CT imaging agents and Ga-labeled MAA represents an attractive alternative to Tc-labeled MAA. We report a simple and rapid NaCl based labeling procedure for the labeling of MAA with Ga using a commercially available MAA labeling kit for Tc. The procedure delivers Ga-labeled MAA with a high specific activity and a high labeling efficiency (>99%). The synthesis does not require a final step of separation or the use of organic solvents.