Paclitaxel-Loaded Magnetic Nanoparticles: Synthesis, Characterization, and Application in Targeting

Iron oxide magnetic nanoparticles (MNPs) are good candidates to implement fluid therapy in critical patients in clinic integrated system. Herein, we synthesized paclitaxel (PTX)-loaded MNPs modified with methoxy polyethylene glycol (PEG)-lysine-oleic acid₂ (PTX-MNPs-PLO), which is expected to act as a magnetic resonance imaging (MRI) contrast agent and meanwhile for cancer therapy. MNPs were synthesized by thermal decomposition. Dialysis method was applied to prepare PTX-MNPs-PLO with 3 different PEG molecular weights (1000, 2000, and 4000 Da), which were subsequently freeze-dried into powders. PTX-MNPs-PLO was characterized by transmission electron microscope, scanning electron microscope, thermogravimetric analysis, vibrating sample magnetometer, and MRI. What is more is that pharmacokinetics and distribution in vivo were processed, the results of which exhibited that PTX-MNPs-PLO₂₀₀₀ had the longer circulation lifetime compared with Taxol, PTX-MNPs-PLO₁₀₀₀, and PTX-MNPs-PLO₄₀₀₀. Results of magnetic targeting in kidneys suggested that deep buried or ultrasmall magnet is likely to be more preferable. PTX-MNPs-PLO₂₀₀₀ holds great promise in the application of magnetic accumulation, target drug delivery, and thermal therapy.