The novel preparation of 99m Tc(I)-labeled human serum albumin (HSA) nanoparticles as a SPECT imaging agent

The purpose of this study was to develop a convenient and robust method for preparation of 99mTc(I)-labeled human serum albumin nanoparticles (HSA-NPs) as a SPECT agent for tumor imaging. Efficient radiolabeling 99mTc to HSA-NPs was achieved by simply reacting [99mTc(OH2)3(CO)3]+ with the reconstituted HSA-NPs solution. The size and morphology of 99mTc(I)-HSA-NPs were analyzed and found not to significantly change after the preformed HSA-NPs were lyophilized or labeled with 99mTc(I). By incubating 99mTc(I)-HSA-NPs in rat plasma at 37 °C for 30 h, 75 % of the radioactivity were found to be remained in the particles, suggesting good in vitro stability.