TY - JOUR
T1 - Effects of various physicochemical characteristics on the toxicities of ZnO and TiO2 nanoparticles toward human lung epithelial cells
AU - Hsiao, I. Lun
AU - Huang, Yuh Jeen
N1 - Funding Information:
We thank the National Science Council (NSC) of the ROC for funding this study and Professors Chien-Hou Wu and Chun-Yu Chuang, Department of Biomedical Engineering and Environmental Sciences, National Tsing-Hua Unversity, for their help with the Zetasizer and biological experiments.
PY - 2011/3/1
Y1 - 2011/3/1
N2 - Although novel nanomaterials are being produced and applied in our daily lives at a rapid pace, related health and environmental toxicity assessments are lagging behind. Recent reports have concluded that the physicochemical properties of nanoparticles (NPs) have a crucial influence on their toxicities and should be evaluated during risk assessments. Nevertheless, several controversies exist regarding the biological effects of NP size and surface area. In addition, relatively few reports describe the extents to which the physicochemical properties of NPs influence their toxicity. In this study, we used six self-synthesized and two commercial ZnO and TiO2 nanomaterials to evaluate the effects of the major physicochemical properties of NPs (size, shape, surface area, phase, and composition) on human lung epithelium cells (A549). We characterized these NPs using transmission electron microscopy, X-ray diffraction, the Brunauer-Emmett-Teller method, and dynamic laser scattering. From methyl thiazolyl tetrazolium (MTT) and Interleukin 8 (IL-8) assays of both rod- and sphere-like ZnO NPs, we found that smaller NPs had greater toxicity than larger ones-a finding that differs from those of previous studies. Furthermore, at a fixed NP size and surface area, we found that the nanorod ZnO particles were more toxic than the corresponding spherical ones, suggesting that both the size and shape of ZnO NPs influence their cytotoxicity. In terms of the effect of the surface area, we found that the contact area between a single NP and a single cell was more important than the total specific surface area of the NP. All of the TiO2 NP samples exhibited cytotoxicities lower than those of the ZnO NP samples; among the TiO2 NPs, the cytotoxicity increased in the following order: amorphous>anatase>anatase/rutile; thus, the phase of the NPs can also play an important role under size-, surface area-, and shape-controlled conditions.
AB - Although novel nanomaterials are being produced and applied in our daily lives at a rapid pace, related health and environmental toxicity assessments are lagging behind. Recent reports have concluded that the physicochemical properties of nanoparticles (NPs) have a crucial influence on their toxicities and should be evaluated during risk assessments. Nevertheless, several controversies exist regarding the biological effects of NP size and surface area. In addition, relatively few reports describe the extents to which the physicochemical properties of NPs influence their toxicity. In this study, we used six self-synthesized and two commercial ZnO and TiO2 nanomaterials to evaluate the effects of the major physicochemical properties of NPs (size, shape, surface area, phase, and composition) on human lung epithelium cells (A549). We characterized these NPs using transmission electron microscopy, X-ray diffraction, the Brunauer-Emmett-Teller method, and dynamic laser scattering. From methyl thiazolyl tetrazolium (MTT) and Interleukin 8 (IL-8) assays of both rod- and sphere-like ZnO NPs, we found that smaller NPs had greater toxicity than larger ones-a finding that differs from those of previous studies. Furthermore, at a fixed NP size and surface area, we found that the nanorod ZnO particles were more toxic than the corresponding spherical ones, suggesting that both the size and shape of ZnO NPs influence their cytotoxicity. In terms of the effect of the surface area, we found that the contact area between a single NP and a single cell was more important than the total specific surface area of the NP. All of the TiO2 NP samples exhibited cytotoxicities lower than those of the ZnO NP samples; among the TiO2 NPs, the cytotoxicity increased in the following order: amorphous>anatase>anatase/rutile; thus, the phase of the NPs can also play an important role under size-, surface area-, and shape-controlled conditions.
KW - Cytotoxicity
KW - Human lung epithelial cell (A549)
KW - Nanomaterial
KW - Occupational health
KW - Physicochemical characteristics
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U2 - 10.1016/j.scitotenv.2010.12.033
DO - 10.1016/j.scitotenv.2010.12.033
M3 - Article
C2 - 21255821
AN - SCOPUS:79851516126
SN - 0048-9697
VL - 409
SP - 1219
EP - 1228
JO - Science of the Total Environment
JF - Science of the Total Environment
IS - 7
ER -