Quantitative analysis of the deposited nanoparticle dose on cell cultures by optical absorption spectroscopy.
OBJECTIVE
The delivered nanoparticle dose to cells in vitro may depend on nanoparticle sedimentation rate. Here, the conditions under which optical absorption spectroscopy can be used to quantify the deposited nanoparticle dose in vitro are investigated.


METHODS
Nanoparticle cytotoxicity in both upright and inverted cell culture orientations is studied in the presence and absence of serum.


RESULTS
Dissolvable nanoparticles, such as ZnO, exhibit no difference in upright and inverted cultures due to dissolved Zn(2+) ions that dominate cytotoxicity. Insoluble nanoparticles, however, exhibit different sedimentation rates and deposited doses that are linked to the observed cytotoxicity.


CONCLUSIONS
The combined use of upright-inverted cell orientations and optical absorption spectroscopy can provide a simple experimental approach to interpret in vitro nano-biointeractions.
Particle Technology Laboratory, Institute of Process Engineering, Department of Mechanical & Process Engineering, ETH Zurich, Sonneggstrasse 3, CH-8092 Zurich, Switzerland.
Anastasia
A
Spyrogianni
Particles-Biology Interactions Laboratory, Department of Materials Meet Life, Swiss Federal Laboratories for Materials Science & Technology (Empa), Lerchenfeldstrasse 5, CH-9014 St Gallen, Switzerland.
Inge K
IK
Herrmann
Scientific Center for Optical & Electron Microscopy (ScopeM), ETH Zurich, Auguste-Piccard-Hof 1, CH-8093 Zurich, Switzerland.
Miriam S
MS
Lucas
Drug Formulation & Delivery, Institute of Pharmaceutical Sciences, Department of Chemistry & Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 3, CH-8093 Zurich, Switzerland.
Jean-Christophe
JC
Leroux
Drug Formulation & Delivery, Institute of Pharmaceutical Sciences, Department of Chemistry & Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 3, CH-8093 Zurich, Switzerland.|Department of Microbiology, Tumor & Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
Georgios A
GA
Sotiriou
D000818:Animals; D018929:Cell Culture Techniques; D002470:Cell Survival; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000633:toxicity*; D051379:Mice; D010316:Particle Size; D000067996:RAW 264.7 Cells; D012995:Solubility; D013053:Spectrophotometry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry
C009495:titanium dioxide; D014025:Titanium; D015034:Zinc Oxide
UV–VIS; cytotoxicity; dosimetry; inverted and upright cell cultures; nanoparticles; sedimentation