Zhen Ye1, 2, Xueming Wu2, Zheng-Rong Lu2
1Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, United States; 2Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
A neutral biodegradable polymeric MRI contrast agent containing macrocyclic Gd chelates, GOLS, were synthesized and evaluated for clinical contrast-enhanced MR imaging. The agent had higher relaxivity than clinical agents, and can be readily degraded. Kinetic stability study showed that this agent had significantly higher stability against transmetallation than polymer based on linear chelates. The contrast-enhancing efficacy of GOLS was evaluated on mice bearing orthotopic 4T1 breast tumor. Significantly higher tumor enhancement was generated by GOLS than clinical agents. This new agent is of great potential as a safe and effective contrast agent in contrast enhanced MRI.