Synthesis and Evaluation of the Cytotoxic and Anti-Proliferative Properties of Dox-ZnO Quantum Dots Loaded Chitosan Nanoparticles against MCF-7 and SKBR-3 Human Breast Cancer Cells

Doxorubicin (Dox) is a potent chemotherapeutic agent used in the treatment of cancer. In the present study, pH responsive chitosan polymer coated Dox nanoparticle (Composite) was developed to investigate targeted drug delivery against breast cancer. The anticancer drug DOX-ZnO QDs was loaded to the chitosan nanoparticles. The synthesized free and drug loaded nanoparticle were analyzed using Fourier transmission electron microscopy (FTIR) and UV-Visible spectroscopy(UV-Vis). The particle size was measured using Transmission Electron Microscopy (TEM). Further, the composite was evaluated for its anticancer effects. Drug release analysis showed significantly larger amount of drug released in acidic pH of 5.0 compared to pH 7.4. The composite was significantly more cytotoxic to the breast cancer cells MCF-7 and SKBR-3. The composite was however, less toxic to HEK-293 human embryonic kidney cells confirming minimum side effects on normal cells andcytotoxic to tumor cells. DAPI staining showed nuclear degradation in composite treated breast cancer cells. The cellular uptake of the composite was analyzed by confocal microscopy. The composite induced a G0/G1 phase arrest in breast cancer cells and the number of colonies formed by the composite treated breast cancer cells formed less number of colonies compared to free NP. Our results showed that our composite could serve as a promising therapeutic approach to improve clinical outcomes against various malignancies.