A rapid assay offers a much-needed way to evaluate nanomaterials’ safety
Source: “Perturbational profiling of nanomaterial biologic activity”
Stanley Y. Shaw et al.
Proceedings of the National Academy of Sciences 105: 7387-7392
Results: Researchers have developed a way to evaluate the safety of nanoparticles by quickly comparing them to nanoparticles already tested for toxicity. They determined the effects of different doses of nanoparticles on a variety of cell types in culture. Then they performed tests in mice, showing that their tests on cells could predict which nanoparticles would have effects in animals similar to those of previously screened nanoparticles.
Why it matters: Hundreds of products containing nanomaterials are already on the market, and more are under development. Few if any of the materials have been thoroughly tested. The new assay is faster and cheaper than testing in animals but appears to give a good approximation of the results; it represents an important step toward speeding up the process of evaluating new nanomaterials. The approach could help researchers choose between similar nanoparticles on the basis of potential safety risks.
Methods: The researchers tested 50 nanoparticles, most of which are being developed for medical imaging, in the four cell types that they are most likely to encounter in the body. Each nanoparticle was tested at four different concentrations in mouse immune cells, human liver cells, and two types of human blood-vessel cells. Automated systems collected data on cell death, metabolic changes, and other signs of toxicity.
Next steps: The experiment, which focused mostly on iron-containing nanoparticles and tiny semiconductor particles called quantum dots, now needs to be extended to other nanomaterials. The assay works well for nanoparticles entering the body intravenously, but to test the properties of nanomaterials that might enter in other ways, including inhalation, future assays will need to use different cell types, such as lung cells.