Figure 1: Magnetic nanoparticles and magnetic vectors: (A) Transmission Electron Microscopy image of the PEI-Mag2 nanoparticles, bar=5 nm. (B) Percent of the magnetically sedimented viral particles vs. MNP-to-Virus ratio (fg Fe/VP). Adenoviral particles labeled with a iodine-127 were assembled with PEI-Mag2 nanoparticles at different MNP-to-VP ratios in PBS for 30 min (curve “PBS”) or further 1-to-1 diluted with Fetal Calf Serum, incubated for the next 30 and then exposed at the Magnetic Plate for 30 min (curve “50%FCS”), non-sedimented radioactivity was measured in a supernatant. (C and D) Magnetophoretic mobility of the magnetic vectors characterized by kinetics of clearance of the suspensions in applied gradient magnetic fields. Figure (C) shows extinction profiles at 410 nm for the suspensions of the magnetic adenoviral complexes registered with a customized LUMiReader® device with 2 disk magnets positioned underneath optical cuvette at multiple points along the vertical axis of the cuvette (STEP-MAG measurements). Schematics at the right panel shows an optical cuvette and a set of Neodymium-Iron-Boron-Magnets positioned underneath the cuvette; resulting magnetic flux density and gradient averaged over vertical sample height were of 0.16 T and 33.5T/m, respectively. (D) Normalized integral Extinction at 410 nm, E/E0, averaged through the probe height versus time upon exposure to magnetic field (MF on) or with no filed applied (no field) and derived data on cumulative distribution functions of the effective magnetophoretic mobility F(u).