Chang-Tong Yang1, Krisada Kittigowittana2, Bingwen Zheng1, Kai-Hsiang Chuang1, Roderick W. Bates2, Xavier Golay1
1Laboratory of Molecular Imaging, Singapore Bio-Imaging Consortium, Agency for Science, Technology and Research, Singapore, Singapore; 2Division of Chemistry and Biological Chemistry, School of Ohysical and Mathematical Sciences, Nanyang Technological University, Singapore
We developed a new class of oligomer-based MRI contrast agents (CAs) by incorporating multi-gadolinium complexes into peptides of controlled length and structure in order to overcome the limitations of both low molecular weight and polymeric macromolecular Gd complexes. Two CAs of GdDO3A conjugated amino acids building blocks derived from glutamic acid and lysine have been synthesized. The T1 relaxivities of two CAs measured at 9.4T are higher than that of clinically used Gd-DTPA and Gd-DOTA. In vivo imaging in rat demonstrated considerable signal enhancement and long blood half-life using GdDO3A-lysine.