pH-responsive polymeric carrier encapsulated magnetic nanoparticles for cancer targeted imaging and delivery

Multifunctional drug delivery systems with favorable compatibility, high selectivity and efficiency are appropriate candidates for future medical applications. For this purpose, a multifunctional nanocomposite that enables selective magnetic resonance imaging and anticancer therapy by encapsulating hydrophobic superparamagnetic nanoparticles and chemotherapeutic agent doxorubicin with a novel biodegradable pH-activated polymeric carrier was synthesized. The as-synthesized amphiphilic polymer has excellent biocompatibility and pH-responsivity. The obtained nanocomposites selectively release the encapsulated drug and magnetic nanoparticles in mildly acidic endosomal/lysosomal compartments due to the degradation of the pH-responsive bonds, resulting in a change of imaging signal and cancer therapy. Furthermore, when compared with the nanocomposites without a targeting moiety, as studied from over-expression of the folic acid receptor tumor cell culturing, the conjugates with folic acid showed a significantly more potent targeting capability.