[The preparation of hepatic receptor imaging agent 99mTc-DTPA-NGA]

The method of preparation and the character of the hepatic receptor imaging agent 99mTc-DTPA-NGA have been presented. The radio-chemical purity of the imaging agent is higher than 95% and the stability of the imaging agent is more than 6 hours in vitro and in human blood. The agent is able to tend to liver and has the character of receptor-intervene-conduct binding. Our comparative study of 99mTc-DTPA-NGA versus 99mTc-NGA reveals, the stability of the former in vitro and in human blood is better than that of the latter. The imaging in rabbits shows that the imaging quality of the former is higher than that of the latter. The radioactive metabolites in urine have been examined. The former does not fall off 99mTc in vivo, but the latter falls off 99mTc clearly. 10 clinical hepatic imagings have had satisfactory results.