Andrew Nencka1, Xiping Liu1, Joy Jeseph1, Shi-Jiang Li1, Balaraman Kalyanaraman1
The conventional T1 contrast agent, gadolinium-DTPA complex, does not cross the blood brain barrier (BBB) in the absence of injury or tumor. Nitroxides possess a single unpaired electron but generally do not cross the BBB. The compound we developed can cross the BBB and provide MRI contrast in brain imaging by shortening the longitudinal relaxation time (T1) of water protons (1). Present study reports the progress of the development of a contrast agent, 2,2,5,5- tetramethylpyrroline 1-oxide 3-ethyleneglycolcarboxylate (CTPO-EG), which can cross the BBB and has significantly greater relaxivity.