Using microsphere technology for the electrochemical measurement of genotoxicity.

Application Identifier: 1813380 Using microsphere technology for the electrochemical measurement of genotoxicity. Project Summary The increasing integration of engineered nanomaterials (ENMs) in personal care products presents significant health and safety challenges. ENMs like titanium dioxide and zinc oxide nanoparticles are highly reactive and capable of penetrating cells, posing unknown long-term risks to human health. Research has demonstrated that these nanomaterials exacerbate DNA damage under ultraviolet (UV) radiation, leading to increased genotoxicity and potentially contributing to cancer initiation. However, current toxicity evaluation methods lack the scalability and precision to assess the combinational effects of ENMs, UV radiation, and chemical agents, leaving a critical gap in public health safety testing. The SphereDNA® platform addresses this gap by introducing a novel high-throughput (HTP) genotoxicity screening approach. Leveraging microfluidic impedance cytometry, SphereDNA® measures DNA damage by detecting changes in electrical impedance as DNA migrates within a 50 µm agarose microsphere. The microsphere encapsulates mammalian cells, and upon lysis, the DNA is unwound in an alkaline environment. Damaged DNA migrates further through the microsphere, proportionally reducing its impedance. This label-free technique eliminates the need for fluorescent imaging, significantly increasing throughput and reproducibility while reducing costs. SphereDNA® is designed for modular scalability, enabling testing of thousands of samples in parallel, making it uniquely suited for evaluating complex exposures under realistic conditions. The platform aligns with the NIEHS Nano Environmental Health and Safety program's goals to detect, quantify, and assess the toxicological potential of ENMs. By providing an innovative and cost-effective solution, SphereDNA® empowers researchers, industry, and regulators to mitigate public health risks and improve oversight of ENM-containing products.