A new technetium-99m labeled isonitrile complex 99mTc-TMCHI as a potential blood pool imaging agent

A new isonitrile ligand 3,3,5-trimethyl cyclohexylisonitrile (TMCHI) and its copper salt [Cu(TMCHI)4BF4] were synthesized and characterized by IR and elemental analysis. 99mTc-TMCHI is prepared by direct labeling method with high RCP. In vitro protein binding in albumin, blood retention and biodistribution of 99mTc-TMCHI in mice indicated that it is mainly accumulated and maintained in blood with a high protein binding rate and low washout rate. The target/non-target ratios in mice are excellent and suggest its use as a cardiac blood pool agent.