Multifunctional poly(aspartic acid) nanoparticles containing iron oxide nanocrystals and doxorubicin for simultaneous cancer diagnosis and therapy

Multifunctional poly(aspartic acid) nanoparticles for simultaneous cancer diagnosis and therapy were developed. First, iron oxide nanocrystals were loaded in poly(aspartic acid) nanoparticles through an emulsion method using octadecyl grafted poly(aspartic acid). The influence of the organic solvent, used to disperse the hydrophobic iron oxide nanocrystals, on the size and loading efficiency of iron oxide nanocrystals loaded poly(aspartic acid) nanoparticles was investigated. Next, an anticancer drug, doxorubicin (DOX), was incorporated in the magnetic poly(aspartic acid) nanoparticles (MPAN). The presence of iron oxide nanocrystals in the poly(aspartic acid) nanoparticles and their size distribution were confirmed by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and dynamic light scattering (DLS), respectively. The drug release behavior was also observed for 3 days. From the results of T2 weighted MR imaging and MTT assays, the DOX loaded MPAN showed high T2 relaxivity coefficients and high cytotoxicity for cancer cells.