Zhigang Tang

Synthesis and biodistribution of a new 99mTc nitrido complex for brain imaging

Bis(N-isobutyl-dithiocarbamato) nitrido technetium-99m complex [99mTcN(IBDTC)2] (IBDTC: N-isobutyl dithiocarbamato) was synthesized by the reduction of 99mTcO4- into [99mTc = N]2+ with stannous chloride in the presence of succinic dihydrazide and propylenediamine tetraacetic acid, followed by the addition of sodium N-isobutyl dithiocarbamate dihydrate. The radiochemical purity of the complex was over 90% as measured by thin layer chromatography. It was stable over 6h at room temperature. Its partition coefficient indicated that it is a good lipophilic complex. Biodistribution in mice demonstrated that the complex accumulated in the brain with high uptake and good retention. The brain uptake (ID%/g) was 6.22, 5.45 and 3.88 and the brain/blood ratio was 1.51, 2.24, 1.84 at 5, 30 and 60 min post-injection, respectively. These results suggest potential usefulness of the complex as a brain perfusion imaging agent.

Development of Radiolabeled Compounds for Myocardial Perfusion Imaging

Coronary artery disease (CAD) is the main cause of death and remains a major health problem worldwide. Myocardial perfusion imaging is a well established noninvasive method for assessing CAD. This review summarizes the development of various radiotracers for myocardial perfusion imaging, including single photon emission computed tomography (SPECT) perfusion imaging agents and positron emission tomography (PET) perfusion imaging agents and introduces novel basic research data related to this area. In addition, the current state of the art in myocardial perfusion imaging agents and the future direction are discussed in this review.

Effects of Tween-80 on the biodistribution of several lipophilic technetium-99m complexes.

The effects of Tween-80 on the biodistributions in mice of (99m)Tc-TBI, (99m)Tc-MIBI, (99m)TcN-TBI and (99m)TcN-MIBI were reported. The studies resulted that liver and blood uptakes of Tween-80 added (TA) complexes significantly lower than that of corresponding non-Tween-80 added (NTA) complexes. And the clearance rate from blood of TA complexes faster than that of NTA complexes. The optimal concentration of Tween-80 was about 1%. It can decrease the lipophilicity of (99m)Tc-complexes and improve the biological properties of the lipophilic (99m)Tc-complexes for myocardial imaging. Its worthy for further studies.