Fig. 5.

Vector association and magnetic sedimentation with magnetic nanoparticles. (a) pDNA association with PEI-Mag2, PL-Mag1 and NDT-Mag1 magnetic nanoparticles in triplexes with Df-Gold (4 μl DF-Gold/1 μg DNA) plotted against magnetic nanoparticle concentration (in terms of iron concentration or iron-to-pDNA w/w ratio). (b) Virus association with PEI-Mag2 magnetic nanoparticles, stability of the resulting complexes in 50% FCS, and magnetic sedimentation of the complexes. ¹²⁵I-labeled virus and magnetic nanoparticles were mixed in OptiMEM at various nanoparticle-to-virus particle ratios at a final virus concentration after complex assembly of 2 × 10⁹ VP/ml and were incubated for 20 min to form the complexes. The resulting complexes were 1-to-1 diluted with OptiMEM or FCS and then incubated for 10 or 30 min before positioning on the 96-magnet plate for 1 h to magnetically sediment the complexes. ¹²⁵I radioactivity in the supernatants was measured to quantify the percentage of virus that associated and magnetically sedimented with MNPs. (c) Self-inactivating lentiviral vector association with SO-Mag2 and ViroMag R/L MNPs. Lentivirus particles were mixed with magnetic nanoparticles in RPMI cell culture medium supplemented with 10% FCS at magnetic nanoparticle:physical virus particle ratios from 0.625 to 40 fg Fe/VP and incubated for 20 min to form the complex. The resulting complexes were positioned at the 96-Magnet magnetic plate for 30 min to sediment the complex. The concentration of the virus particles in the supernatants was determined using p24 ELISA to quantify the percentage of virus particles that were associated and magnetically-sedimented with the magnetic nanoparticles.

Panel (a) was reproduced with permission from Inderscience Enterprises Ltd. [79]. Panel (b) was reproduced with permission from ACS Publications: Molecular Pharmaceutics [55]. Panel (c) was from research originally published in Blood. Sanchez-Antequera et al. Magselectofection: an integrated method of nanomagnetic separation and genetic modification of target cells. Blood. 2011;117:e171-e181. © the American Society of Hematology. Reproduced with permission from the American Society of Hematology: Blood [83].