Optimizing retention of multimodal imaging nanostructures in sentinel lymph nodes by nanoscale size tailoring

Three different sizes of multimodal USPIOs were injected subcutaneously in one of the hind paws of healthy rats. The retention of particles in the first three lymph nodes in the lymphatic drainage pathway was imaged with MRI and fluorescent microscopy and the amount of iron in the nodes was assessed by ICP-OES. The results suggest that the smallest particle (15 nm) accumulates more rapidly and to a higher amount in the sentinel lymph nodes than the two larger ones (27 nm and 58 nm).190