Magnetic resonance signal detection of superparamagnetic iron oxide nanoparticles and its biological effects on endothelial cells

To investigate the magnetic resonance (MR) signal changes of superparamagnetic iron oxide (SPIO) and its biological effects on endothelial cells. The citric-acid coated SPIO was synthesized by co-precipitation method. The human umbilical vein endothelial cells (HUVECs) were incubated with SPIO for 24 h in culture medium at iron concentration of 0.01, 0.05, 0.10, 0.15 mg/ml (experimental groups), and the cells incubated without SPIO served as control groups. The uptake efficiency of intracellular iron was measured by Prussian blue staining, and the cell viability was monitored by Calcein-AM method. The cell cytoskeleton (F-actin and tubulin), adherence and migration capacity were measured by immunofluorescence staining. The iron oxide nanoparticles distribution and the cellular organelle change were monitored by transmission electron microscopy (TEM). Quantification of particle uptake was measured by atomic absorption spectrometry. The MR signal of endothelial cells after labeling was monitored by Philips 3.0