The Characterization and Imaging Behavior of a New Developed Paramagnetic Contrast Agent NMG2[Gd(TTDA-BOM)]

[Gd(TTDA-BOM)]
^2-
is a newly developed paramagnetic contrast agent.The ligand,TTDA-BOM,bears a benzyloxymethyl group so that the lipophilicity is increased. The water exchange rate for [Gd(TTDA-BOM)]
^2-
is significantly higher than that of [Gd(DTPA)]
^2-
and [Gd(BOPTA)]
^2-
.In addition, the bound relaxivity of this Gd (III) complex has a remarkably high value with HSA. Therefore,it has potential to be used as a blood pool contrast agent for MRI. The aim of this study is to investigate the characterization and imaging behavior of NMG
2
[Gd(TTDA-BOM)] in normal rat livers and hearts using a 3T high field whole-body MR scanner.The high field MR scanner is expected to have a higher signal to noise ratio. The relaxivities r
1
and r
2
for [Gd(TTDA-BOM)]
^2-
at 3T are 5.97 mM
^-1
s
^-1
and 7.99 mM
^-1
s
^-1
respectively, which are higher than those for [Gd(DTPA)]
²
(r1=4.64 mM
^-1
s
^-1
and r
2
= 5.08 mM
^-1
s
^-1
). The dynamic MRI studies show that there is marked enhancement in livers and hearts right after the bolus injection and the enhancement ratios keep high until two hours. In conclusion, [Gd(TTDA-BOM)]
^2-
might have a good potential in both cardiovascular and hepatobiliary applications.