Improvement of the antitumor activity of doxorubicin by the use of magnetic nanoplatforms

Improvement of the antitumor activity of doxorubicin by the use of magnetic nanoplatforms The introduction of magnetic nanoplatforms in the cancer arena is intended to optimize the accumulation of the drug dose into the tumor interstitium with the help of a magnetic gradient. As a result, the chemotherapeutic agent may exhibit an enhanced anticancer efficacy and a negligible systemic toxicity. In these contexts, we have developed a reproducible methodology for the design of magnetite/poly (epsilon-caprolactone) core/shell nanoparticles. A detailed physicochemical characterization of these nanocomposites suggested that their heterogeneous structure allows their use in drug delivery, thanks to an excellent responsiveness to magnetic gradients. In vitro heating characteristics (hyperthermia inducing capability) of the core/shell nanoparticles were investigated in a high frequency alternating magnetic gradient. Blood compatibility of the nanoformulation was defined in vitro. Finally, this nanodevice was used to enhance the intravenous delivery of the anticancer agent doxorubicin to the tumor tissue. The nanocomposites were characterized by an adequate doxorubicin loading, a significant magnetic susceptibility, and a low burst drug release. When injected to the EMT6 subcutaneous mice tumor model, these doxorubicin-loaded core/shell nanoparticles were magnetically guided, and they displayed considerably greater anticancer activity than the other anticancer treatments (i.e., doxorubicin-loaded nanocomposites non-magnetically guided, or doxorubicin free in solution). Thus, the here-described stimuli-sensitive nanomedicine possesses important characteristics for effective therapy of cancer.