Optimal Field Strength for Molecular MR Imaging : Detection of Targeted Gd-Based Contrast Agents on a Living Cell Monolayer

Nicolas Gargam¹, Marie Poirier-Quinot¹, Jean-Christophe Ginefri², Jean-Sebastien Raynaud³, Philippe Robert³, Luc Darrasse¹

The variation of relaxivity of macromolecular contrast agent as a field function, and the contrast to noise then induced, had already been studied in vitro, but had not yet been highlighted in live cells. The dynamic uptake of a Gd-based nanoemulsion by a cell monolayer is investigated here at 2 field strenghts, 4.7 T to 2.35 T, leading to a signal enhancement of 2.7. That results tends to be in line with in vitro theoretical study showing the efficiency of a paramagnetic nanoemulsion as a field function, raising the question of the optimal field strenght for molecular MR Imaging.