RESUMO
OBJECTIVE: To prepare Gd-DOTA-E-2 targeted contrast agent and evaluate its relaxation properties, cytotoxicity and targeting. METHODS: E-2 was synthesized by F-moc solid phase method, covalently bonded with chelating agent DOTA, meanwhile ultilizing chelating ligand Gd3+ to prepare MRI contrast agent Gd-DOTA-E-2. The structure was characterized by ESI-MS and NMR, and the properties were evaluated by relaxation properties, MTT and mouse MRI contrast assay. RESULTS: ESI-MS and NMR RESULTS showed that Gd-DOTA-E-2 was synthesized successfully, and its relaxation efficiency(k=9.551 mmol-1•L•s-1) is 1.84 times more efficient than a commercially available contrast agent of Gd-DOTA; MTT RESULTS showed that the toxicity of Gd-DOTA-E-2 cell is lower than that of Gd-DOTA; the experimental RESULTS in MRI angiography showed that Gd-DOTA-E-2 is possessing of targeting and can image clearly. CONCLUSION: Gd-DOTA-E-2 is a kind of MRI contrast agent with good stability, low cytotoxicity and targeted properties in vivo,which is valuable in research and application.