Furthermore, by incorporating a layer of PEI on the surface of the HSA nanoparticles, we aimed to increase their cellular uptake in the tumor tissue. Previously, uncoated HSA nanoparticles were studied for the delivery of DOX to neuroblastoma cell lines. Results suggested that DOX delivered using nanoparticles was more cytotoxic against cancer cells as compared to free DOX. In our study, we observed that the cytotoxicity Inhibitors,research,lifescience,medical of DOX-loaded nanoparticle

and free DOX against MCF-7 breast cancer cells was about the same after 48hrs as the DOX concentration was increased, shown in Figure 4(a). However, assessing the cytotoxicity at different time points in Figure 4(b) showed that DOX-loaded nanoparticles led to a greater decrease in cell viability as compared to free DOX after 144hrs. This observation can be explained by the slow release of DOX from the nanoparticles. These results would be more effective in vivo as the free drug would diffuse out of the tumor tissue, while the Inhibitors,research,lifescience,medical nanoparticles would accumulate within the tumor tissue due to the EPR Dorsomorphin concentration effect and release the drug over time. Images of treated cells after Inhibitors,research,lifescience,medical TUNEL staining in Figures5(a), 5(b), and 5(c)

confirm that the cytotoxic effect of DOX-loaded nanoparticles was comparable to free DOX. Figure5(c) shows that the cells remained healthy and viable after the addition of PEI-enhanced HSA nanoparticles,

suggesting that the nanoparticle formulation does not have cytotoxic effects. Figure 4 : (a) Dose-response cytotoxicity of DOX-loaded PEI-enhanced HSA nanoparticles as compared to free DOX administered to MCF-7 breast cancer cells in log-phase culture after 48hrs of treatment Inhibitors,research,lifescience,medical Inhibitors,research,lifescience,medical with different concentrations of DOX. (b) Time of exposure: … Figure 5 TUNEL assay to confirm cell death after DOX administration (24hrs): (a) DOX-loaded PEI-enhanced HSA nanoparticles, (b) free DOX, and (c) empty PEI-enhanced HSA nanoparticles. The concentration of DOX administered was 1μg/mL to … 4. Conclusion In our current study, we used modified HSA nanoparticles by adding an outer coating of the polyethylenimine (PEI) to improve the therapeutic index of doxorubicin against MCF-7 breast cancer cells. The nanoparticles prepared were characterized based upon size and surface charge with respect to the amount of PEI used for coating. A rise in Resminostat the surface zeta potential of the nanoparticles confirms the electrostatic binding of PEI with the surface of HSA nanoparticles. Different microscopic techniques were employed to observe the shape, dispersion, and morphology of the nanoparticles. PEI-enhanced HSA nanoparticles resulted in a higher cell transfection percentage, indicating that the addition of the layer of cationic polymer did improve cell penetration of the particles.