Impact of pH changes on metal oxide nanoparticle behaviour during artificial digestion

The properties of orally ingested nanoparticles can be influenced by the conditions prevailing in the digestive tract. The influence of the pH value on the fate of metal oxide nanoparticles was demonstrated using a simplified digestion approach.

Altitude Test Facility Humidity Control to Generate Defined Icing Conditions

In altitude test facility (ATF) operation, the requirements to control humidity to generate defined icing conditions are gaining more and more importance. In this context, the ability to predict humidity and condensation becomes a fundamental part of ATF control. For this purpose, classical nucleation theory has been applied in combination with in situ measurements to derive a model suitable to predict the onset of condensation during very low temperature ATF operation. The model parameters have been acquired inside the ATF of the University of Stuttgart downstream of its air coolers. This makes the application or assumption of generalized atmospheric aerosol data unnecessary. Polydisperse nano aerosol distributions were measured and statistically evaluated, showing that a constant distribution of nano aerosol particle size can be assumed. The composition of the ingested nanoparticles was analyzed and Arizona test dust was chosen as a valid substitute material for the application in the prediction model leading to a conservative prediction. The approach has been successfully verified using optical measurements during ATF testing. Its prediction accuracy fulfills the requirements of ATF control for a variety of icing conditions in component and engine altitude testing.

Critical assessment of toxicological effects of ingested nanoparticles

Review of the properties of food-relevant nanoparticles including gastrointestinal tract exposure, transport, and immunogenicity.

Body-on-a-chip simulation with gastrointestinal tract and liver tissues suggests that ingested nanoparticles have the potential to cause liver injury

The use of nanoparticles in medical applications is highly anticipated, and at the same time little is known about how these nanoparticles affect human tissues.

Internalization of Consumed Nanoparticles by a Model Invertebrate Organism

There is littlein vivodata concerning the fate of ingested TiO2nanoparticles (nano-TiO2). We report here experiments aimed at assessing if ingested nano-TiO2accumulates in the digestive gland epithelium or are internalized elsewhere in the body of the terrestrial isopod crustaceans. The animals (Porcellio scaber, Isopoda, Crustacea) fed for 3, 7, or 14 days on food dosed with 100 or 1000 μg nano-TiO2showed no evidence of internalization of Ti measured by microparticle-induced X-ray emission method. The effect of ingested nanoparticles was measured by conventional toxicity measures such as feeding rate, weight change, and mortality and did not indicate any toxicity. However, cell membrane of digestive glands, measured with a modified method for assessing cell membrane stability, was affected already after 3 days of exposure to 1000 μg nano-TiO2per gram dry weight of food indicating cytotoxic potential of ingested nanoparticles. Our results confirmed hypothesis on low toxic potential and no internalization of consumed TiO2nanoparticles by a model invertebrate organism. However, cytological marker unequivocally indicated adverse effect of ingested nano-TiO2. We conclude that the isopod model system could be used for studying the fate and effect of ingested nanoparticles.