Polymorph- and size-dependent uptake and toxicity of TiO₂ nanoparticles in living lung epithelial cells.
The cellular uptake and distribution of five types of well-characterized anatase and rutile TiO(2) nanoparticles (NPs) in A549 lung epithelial cells is reported. Static light scattering (SLS), in-vitro Raman microspectroscopy (μ-Raman) and transmission electron spectroscopy (TEM) reveal an intimate correlation between the intrinsic physicochemical properties of the NPs, particle agglomeration, and cellular NP uptake. It is shown that μ-Raman facilitates chemical-, polymorph-, and size-specific discrimination of endosomal-particle cell uptake and the retention of particles in the vicinity of organelles, including the cell nucleus, which quantitatively correlates with TEM and SLS data. Depth-profiling μ-Raman coupled with hyperspectral data analysis confirms the location of the NPs in the cells and shows that the NPs induce modifications of the biological matrix. NP uptake is found to be kinetically activated and strongly dependent on the hard agglomeration size-not the primary particle size-which quantitatively agrees with the measured intracellular oxidative stress. Pro-inflammatory responses are also found to be sensitive to primary particle size.
FOI, Cementvägen 20, SE-901 82 Umeå, Sweden.
Per Ola
PO
Andersson
Christian
C
Lejon
Barbro
B
Ekstrand-Hammarström
Christine
C
Akfur
Linnéa
L
Ahlinder
Anders
A
Bucht
Lars
L
Osterlund
D002460:Cell Line; D018932:Chemokine CCL2 / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D008168:Lung / Q000166:cytology*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000633:toxicity* / Q000648:ultrastructure; D013059:Spectrum Analysis, Raman; D014025:Titanium / Q000378:metabolism* / Q000633:toxicity*
C111835:CCL2 protein, human; D018932:Chemokine CCL2; D016209:Interleukin-8; C009495:titanium dioxide; D014025:Titanium