A clear understanding of physicochemical factors governing nanoparticle toxicity is still in its infancy. We used a systematic approach to delineate physicochemical properties of nanoparticles that govern cytotoxicity. the cytotoxicity of fourth period metal oxide nanoparticles (NPs): TiO2, Cr2O3, Mn2O3, Fe2O 3, NiO, CuO, and ZnO increases with the atomic number of the transition metal oxide. This trend was not cell-type specific, as observed in non-transformed human lung cells (BEAS-2B) and human bronchoalveolar carcinoma-derived cells (A549). Addition of NPs to the cell culture medium did not significantly alter pH. Physiochemical properties were assessed to discover the determinants of cytotoxicity: (1) point-of-zero charge (PZC) (i.e., isoelectric point) described the surface charge of NPs in cytosolic and lysosomal compartments; (2) relative number of available binding sites on the NP surface quantified by X-ray photoelectron spectroscopy was used to estimate the probability of biomolecular interactions on the particle surface; (3) band-gap energy measurements to predict electron abstraction from NPs which might lead to oxidative stress and subsequent cell death; and (4) ion dissolution. Our results indicate that cytotoxicity is a function of particle surface charge, the relative number of available surface binding sites, and metal ion dissolution from NPs. These findings provide a physicochemical basis for both risk assessment and the design of safer nanomaterials.
- chromium oxide nanoparticle,
- copper oxide nanoparticle,
- iron oxide nanoparticle,
- manganese oxide nanoparticle,
- metal oxide,
- nanoparticle,
- nickel oxide nanoparticle,
- titanium oxide nanoparticle,
- unclassified drug,
- zinc oxide nanoparticle,
- apoptosis,
- article,
- binding site,
- carcinoma cell,
- cell compartmentalization,
- cell viability,
- controlled study,
- cytotoxicity,
- human,
- human cell,
- isoelectric point,
- molecular interaction,
- nanoanalysis,
- nanotoxicology,
- oxidative stress,
- particle size,
- physical chemistry,
- prediction,
- quantitative analysis,
- surface property,
- X ray photoelectron spectroscopy,
- Cytotoxicity,
- Metal ion dissolution,
- Metal oxide nanoparticles,
- Physicochemical properties,
- Point-of-zero charge,
- Surface binding sites,
- Apoptosis,
- Binding Sites,
- Cell Line, Tumor,
- Cell Survival,
- Humans,
- Hydrogen-Ion Concentration,
- Metal Nanoparticles,
- Oxides,
- Surface Properties,
- Transition Elements,
- Cytotoxicity,
- Metal ion dissolution,
- Metal oxide nanoparticles,
- Physicochemical properties,
- Point-of-zero charge,
- Surface binding sites
Available at: http://works.bepress.com/jeffrey-winiarz/6/