Development of MnO₂ hollow nanoparticles for potential drug delivery applications

This study reports the development of hollow nanoparticles, formed from manganese dioxide (δ-MnO₂) sheets, that are coated with polydopamine for potential immobilization of chemical agents. The biodegradability and colloidal stability of the uncoated hollow MnO₂ nanoparticles were investigated in comparison to commercially synthesized solid MnO₂ nanoparticles and graphene oxide sheets. The MnO₂ hollow nanoparticles degraded at a faster rate and seem to have a higher surface area and better colloidal dispersion than solid MnO₂ nanoparticles. Xanthan gum (as a dispersant) was proven to improve colloidal dispersion of these hollow nanoparticles and were used for further cell studies. In this study, cancer and healthy cells were treated with coated hollow nanoparticles, and the studies indicate that this novel nanoparticle can internalize cells. Particle aggregation has shown to inhibit cell growth. Further studies with this novel hollow nanoparticle may lead to a groundbreaking solution to new drug delivery systems for cancers or other applications. (paper)