Dual-Shell Nanocomposites for Enhanced Therapeutic Applications in Cancer Treatment

A combination of endoskeleton and exoskeleton in a dual shell has been considered for simultaneously improving the core–satellite binding efficiency and stability. A two-step preassembling-postgrowth approach has been considered for fabricating dual stimulus-responsive core–shell–satellite–shell (CSSS) nanocomposites. A CSSS therapeutic nanosystem has been designed for controllable release of the drug and in situ monitoring of chemotherapy via a dual stimulus-responsive mode. Incorporation of bifunctional SH-PNIPAM-COOH (TPNIC) in the nanocomposites plays a dual role in cross-linking of core–satellites and stimulus-responsive Raman enhancement. On the one hand, TPNIC in swelling status can act as a cross-linker for assembling Au satellites on the PFe3O4 (PEI-functionalized Fe3O4) core. On the other hand, TPNIC can adjust the assembling status of Au satellites via alteration of temperature; moreover, it induces optical hot-spot generation for giving a coupling plasmonic effect to produce a much stronger SERS performance than simple assembling. Thus, collapse of the TPNIC layer in the nanocomposites above the lower critical solution temperature (LCST) can be adopted for in situ enhanced monitoring chemotherapeutics of releasing the drug doxorubicin in a tumor microenvironment (TME). The dual stimulus-responsive therapeutic nanosystem can contribute to delivering the anticancer drug for efficiently penetrating the cell membrane and retarding release of the anticancer drug in TME. The obvious advantages of the therapeutic nanosystem are its facile magnetic recycling and regeneration so as to realize a sustainable chemotherapy of the tumor.