Doxorubicin-loaded biodegradable capsules: Temperature induced shrinking and study of cytotoxicity in vitro

Doxorubicin (DOX) is one of mainstays in anticancer therapy due to its universal anticancer activity. Development of DOX delivery systems is of particular importance aiming a reduction in its non-targeted toxicity and improvement of the treatment efficiency. In this study, biodegradable polyelectrolyte multilayer capsules from a dextran sulfate (DS) and poly- l -arginine (Parg) couple for intracellular DOX delivery has been developed. The capsules were fabricated by layer-by-layer (LbL) technique using vaterite particles (500 ± 100 nm) as sacrificial templates. An elegant approach for simultaneous miniaturization of the capsules down to a size of 290 ± 60 nm and DOX loading was elaborated. Cytotoxicity of the DOX-loaded capsules was evaluated in vitro using human breast adenocarcinoma MCF-7 and DOX-resistant MCF-7/ADR cells. Penetration and accumulation of the capsules in the cells were studied by confocal microscopy and flow cytometry. The pronounced accumulation of the DOX-loaded shrunken capsules in MCF-7/ADR cells suggested overcoming drug resistance. The developed capsules could be promising for both anticancer therapy and diagnostic purposes.