Zinc-activated contrast agents
The present invention relates to contrast agents for magnetic resonance imaging (MRI). In particular, the present invention relates to MRI contrast agents that are activated in the presence of zinc(II) (e.g., resulting in a brighter image).
1. A zinc activated contrast agent that selectively binds Zn(II) over Ca(II) and Mg(II), wherein said contrast agent displays an increase in relaxivity upon zinc binding, and wherein said agent is:
wherein R═(CH 2 ) n (n=1 or 2).
2. A method for magnetic resonance imaging comprising:
a) treating a biological sample with a zinc activated contrast agent that selectively binds Zn(II) over Ca(II) and Mg(II), wherein said contrast agent displays an increase in relaxivity upon zinc binding and brighter images in the presence of zinc, wherein said agent is and
b) detecting signal.
3. The zinc activated contrast agent of claim 2 , wherein said agent reversibly binds Zn(II).