Doxorubicin-conjugated core-shell magnetite nanoparticles as dual-targeting carriers for anticancer drug delivery.

The present study reports the successful synthesis of core-shell nanostructures composed of magnetite nanoparticles (Fe3O4-NPs) conjugated to the anticancer drug doxorubicin, intended for dual targeting of the drug to the tumor sites via a combination of the magnetic attraction and the pH-sensitive cleavage of the drug-particle linkages along with a longer circulation time and reduced side effects. To improve the carrier biocompatibility, the prepared nanocarrier was, finally coated by chitosan. FT-IR analysis confirmed the synthesis of functionalized Fe3O4-NPs, doxorubicin-conjugated Fe3O4-NPs, and chitosan-coated nanocarriers. Scanning electron microscopy (SEM) indicated the formation of spherical nanostructures with the final average particle size of around 50 nm. The vibrating sample magnetometer (VSM) analysis showed that the saturation magnetization value (Ms) of carrier was 6 emu/g. The drug release behavior from the nanocarriers was investigated both in acidic and neutral buffered solutions (pH values of 5.3 and 7.4, respectively) and showed two-fold increase in the extent of drug release at pH 5.3 compared to pH 7.4 during 7 days. The results showed that the dual-targeting nanocarriers responded successfully to the external magnetic field and pH. From the results obtained, it can be concluded that this methodology can be used to target and improve therapeutic efficacy of the anticancer drugs.