Figure 7.
T2-weighted image of A431 and 32D cells at different doses of the synthesized SPIONs. A431 and 32D cells were incubated at 37°C for 2 hours with PEG-dexSPIONs or cet-PEG-dexSPIONs at iron concentrations of 10, 20, 40, 80, and 160 μg/mL. Tumor cells treated with fresh culture medium alone served as a control. The excess iron was removed by washing with 1× PBS, and the cells were suspended in a 1% agarose gel for the following in vitro MRI analysis using a 4.7 T scanner. The agarose gel containing PBS alone without any cells was used as a blank. The plot of the MRI signal intensity as a function of the iron concentration of the synthesized SPIONs revealed the MRI capability of the synthesized magnetic nanoparticles.
Abbreviations: cet, cetuximab; dex, dextran; MRI, magnetic resonance imaging; PEG, polyethylene glycol; PBS, phosphate-buffered saline; SPIONs, superparamagnetic iron oxide nanoparticles; a.u., arbitrary units.