Development of an automated high-throughput screening procedure for nanomaterials genotoxicity assessment

(Nanowerk News) In this project, an automated procedure for high-throughput screening of the genotoxicity of synthetic nanoparticles has been developed. The project was undertaken by the University of South Australia, Flinders University and CSIRO. The report describes the successful development of an automated procedure for high-throughput genotoxicity assessment of different types of engineered nanomaterials.
The project report is available as a free download from the Safe Work Australia website: "Development of an automated high-throughput screening procedure for nanomaterials genotoxicity assessment".
Surface-engineered microarrays were used in order to provide in situ cell sorting, localisation, and immobilisation of various subsets of human primary lymphocytes, suitable for on-chip bioassays. The microarray platform was then integrated with the CBMN assay for analysis of the genotoxicity of specific subsets of human peripheral lymphocytes exposed to nanoparticles. Protocols suitable for automated scanning, imaging and analysis of microarrays for the assessment of micronuclei in binucleated (BN) cells (to examine genotoxicity) and nuclear division index (NDI) (an indicator of cytotoxicity) were developed.
The genotoxic effect of silver nanoparticles (AgNPs), with different size and surface coating, were assessed. The genotoxic impact of nanoparticles on human B lymphocyte cell line was examined successfully using the screening method. Preliminary investigations of primary human lymphocyte genotoxicity has indicated that short exposure time and low nanoparticle concentrations need to be used to examine genotoxicity effects using the CBMN assay.
The key features of the approach described are that it requires very small volumes of reagents, allows sorting of lymphocyte subsets in situ, increases throughput of cell assays and is amenable to high content microscopy analysis, which is important when considering the growing number of different nanoparticle formulations already on the market and in development.
In summary, this proof-of-principle project has been successful in developing procedures for lymphocyte separation, nanoparticle incubation, fluorescence staining and automated scoring of microarray experiments to determine the extent of genotoxicity and make comparison between the different nanoparticle concentrations, particle chemistries and particle sizes.
In ongoing work, the authors will use these procedures for the genotoxicity assessment of different type of nanomaterials on human primary lymphocytes.
Source: Safe Work Australia