[Truncated abstract] Chelated gadolinium compounds and magnetic nanoparticles have been developed for use as magnetic resonance imaging (MRI) contrast agents. However, both chelated gadolinium compounds and magnetic particles are rapidly cleared from the blood stream, gadolinium via renal excretion and magnetic nanoparticles by the reticulo-endothelial system. In order to extend the lifetime of the contrast agents in the blood stream, we have encapsulated contrast agents within red blood cells (RBCs) as a potential strategy for slowing their clearance from the blood pool. A key strategy for loading RBCs with contrast agent is to incubate them in the presence of the contrast agents under hypo-osmolar conditions. Under these conditions the cells swell and holes open up in the cell membranes allowing particles to pass into or out from the cell. The RBCs can be re-sealed by bringing the osmolarity of the medium back up to physiological values. Human RBCs were loaded with magnetic nanoparticles and gadoteric acid by two different methods. The methods comprised either hypo-osmolar incubation or a hypo-osmolar pulse in the presence of gadoteric acid or magnetic nanoparticles. The efficacy of the resulting RBCs as contrast agents for MRI was assessed by measuring the cell specific longitudinal and transverse proton relaxivities in a magnetic field of magnitude 1.4T...
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2013|