Dispersion and Stability Optimization of TiO₂ Nanoparticles in Cell Culture Media

Abstract

Accurate evaluation of engineered nanomaterial toxicity requires not only comprehensive physical-chemical characterization of nanomaterials as produced, but also thorough understanding of nanomaterial properties and behavior under conditions similar to those used for in vitro and in vivo toxicity studies. In this investigation, TiO2 nanoparticles were selected as a model nanoparticle and bovine serum albumin (BSA) was selected as a model protein for studying the effect of protein-nanoparticle interaction on TiO2 nanoparticle dispersion in six different mammalian, bacteria, and yeast cell culture media. Great improvement in TiO2 dispersion was observed upon the addition of BSA, even though the degree of dispersion varied from medium to medium and phosphate concentration in the cell culture media was one of the key factors governing nanoparticle dispersion. Fetal bovine serum (FBS) was an effective dispersing agent for TiO2 nanoparticles in all six media due to synergistic effects of its multiple protein components, successfully reproduced using a simple “FBS mimic” protein cocktail containing similar concentrations of BSA, γ-globulin, and apo-transferrin.

Downregulation of B-cell lymphoma/leukemia-2 by overexpressed microRNA 34a enhanced titanium dioxide nanoparticle-induced autophagy in BEAS-2B cells

“…This is consistent with reports of poor dispersion in other serum-free media, 41 presumably due to decreased protein corona levels that act as surfactants to reduce particle aggregation. Zeta potentials can provide quantitative information on the stability of the particles, which confirm that the particles are more likely to remain dispersed if absolute values of zeta potentials are higher than 30 mV.…”

Titanium dioxide induces apoptotic cell death through reactive oxygen species-mediated Fas upregulation and Bax activation

“…The sub-100 nm fraction (ie, TiO 2 P25-70 ) was found to be stable without agglomeration and sedimentation for more than a week, whereas the TiO 2 P25-300 and TiO 2 P25-130 fractions were easily aggregated and sedimented in slight acidic conditions (pH [4][5] cause problems in performing accurate and reproducible toxicity assessments of nanoparticles. 5,[23][24][25][26][27] To overcome this problem of colloidal instability, nanoparticles are often stabilized with various surface-modifying ligands. 19 In this study, rather than adding additional surface-modifying compounds, fetal bovine serum (a supplement used for in vitro cell culture) was used as an efficient stabilizing agent.…”

Adsorption and Conformation of Serum Albumin Protein on Gold Nanoparticles Investigated Using Dimensional Measurements and in Situ Spectroscopic Methods

“…Additional studies have established the general efficacy of albumin proteins as dispersing agents for a range of nanomaterials in different biological media. [21][22][23][24] Furthermore, albumin continues to be used as a model protein for many biophysical and biochemical studies. 6,[25][26][27] Bovine serum albumin (BSA) is the most widely utilized serum protein due to its low cost, wide availability, and structural/ functional similarity to human serum albumin (HSA)-having 76% sequence homology 28 and nearly identical pH-dependent conformational transitions.…”