Synthesis, characterization and anticancer effect of doxorubicin-loaded dual stimuli-responsive smart nanopolymers

Nanopolymers represent a significant group of delivery vehicles for hydrophobic drugs. In particular, dual stimuli-responsive smart polymer nanomaterials might be extremely useful for drug delivery and release. We analyzed the possibility to include the known antitumor drug doxorubicin (DOX), which has antimitotic and antiproliferative effects, in a nanopolymer complex. Thus, doxorubicin-loaded temperature- and pH-sensitive smart nanopolymers (DOX-SNPs) were produced. Characterizations of the synthesized nanostructures were carried out including zeta potential measurements, Fourier-transform infrared spectroscopy, and scanning electron microscopy. The loading capacity of the nanopolymers for DOX was investigated, and encapsulation and release studies were carried out. In a final step, the cytotoxicity of the DOX–nanopolymer complexes against the HeLa cancer cell line at different concentrations and incubation times was studied. The DOX release depended on temperature and pH value of the release medium, with the highest release at pH 6.0 and 41 °C. This effect was similar to that observed for the commercial liposomal formulation of doxorubicin Doxil. The obtained results demonstrated that smart nanopolymers can be efficiently used to create new types of doxorubicin-based drugs.