Magnetic Accumulation of SPIONs under Arterial Flow Conditions: Effect of Serum and Red Blood Cells

Abstract

Magnetic drug targeting utilizes an external magnetic field to target superparamagnetic iron oxide nanoparticles (SPIONs) and their cargo to the diseased vasculature regions. In the arteries, the flow conditions affect the behavior of magnetic particles and the efficacy of their accumulation. In order to estimate the magnetic capture of SPIONs in more physiological-like settings, we previously established an ex vivo model based on human umbilical cord arteries. The artery model was employed in our present studies in order to analyze the effects of the blood components on the efficacy of magnetic targeting, utilizing 2 types of SPIONs with different physicochemical characteristics. In the presence of freshly isolated human plasma or whole blood, a strong increase in iron content measured by AES was observed for both particle types along the artery wall, in parallel with clotting activation due to endogenous thrombin generation in plasma. Subsequent studies therefore utilized SPION suspensions in serum and washed red blood cells (RBCs) at hematocrit 50%. Interestingly, in contrast to cell culture medium suspensions, magnetic accumulation of circulating SPION-3 under the external magnet was achieved in the presence of RBCs. Taken together, our data shows that the presence of blood components affects, but does not prevent, the magnetic accumulation of circulating SPIONs.

Loading of Primary Human T Lymphocytes with Citrate-Coated Superparamagnetic Iron Oxide Nanoparticles Does Not Impair Their Activation after Polyclonal Stimulation

“…However, before starting experiments in animal models it is necessary to test how the SPION-loaded T cells behave under flow conditions and at a greater distance from the magnet. For this purpose, a setup like the one used by Hennig et al can be used [40]. Others also showed the ability of SPION-loaded T and NK cells to be magnetically attracted in a flow chamber in vitro [23,25].…”

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

“…Hydrophobic particles are rapidly recognized and engulfed by the reticuloendothelial system [ 85 , 96 ]. Hennig et al [ 97 ] obtained lauric acid/BSA-coated and dextran-coated SPIONs with neutral surface charge, which remained colloidally stable without forming any aggregates. This feature is very important for cell endocytosis, as aggregates precipitate between cells in vitro and therefore give incorrect results.…”

“…They used two types of SPIONs, namely lauric acid/BSA-coated and dextran-coated SPIONs, and observed that when used in plasma or in whole blood, they produce clotting. However, both types of SPIONs cross the walls and accumulate in the tissue [ 97 ]. Wei et al used 80 nm PEG-coated SPIONs capped with epidermal growth factor and green fluorescent protein to target atherosclerotic plaques for MRI detection in vivo with good biocompatibility and good targeting resolution, showing that for this application retention time and dimension of the PEG-coated SPIONs were ideal [ 131 ].…”

Investigation of Particle Steering for Different Cylindrical Permanent Magnets in Magnetic Drug Targeting

“…In MDT, usually superparamagnetic iron oxide nanoparticles (SPIONs) are used as drug delivery carriers [6]. These particles consist of a small iron oxide core and, thus, are only composed of a single magnetic domain.…”