TiO2
nanoparticles are widely used for industrial and
medical applications. 38,39 Because nanoparticles can interact with cell membranes and intracellular organelles in a
manner not totally understood, there are increasing
concerns about the adverse health effects of TiO2 and
other nanoparticles. The first part of this study was to
analyze the cell toxicity effects of unmodified TiO2. Among
the five cell lines used in this investigation, we find that
TiO2 nanoparticles have low cytotoxicity to B16F10 and
B16F1 melanoma cells as well as 3T3 fibroblasts. These
findings are in agreement with many recent published
results. Specifically, various sizes and concentrations of
TiO2
particles have been reported to be nontoxic in cell
monolayer uptake models in vitro, 40,41 in vitro inhalation
models, 3
and in vivo models. 5,10 However, in the case of
the JHU prostate tumor cells and LLC cells, we found that
there are significant differences in viability levels for
uncoated TiO2 particles at concentrations of 1 mg/mL for
LLC cells and 0.1 mg/mL for JHU prostate tumor cells. Our
results have shown that TiO2 particles possess cell-specific
toxicity, depending on the concentrations and surface
functionality of the particular particles.