Development of Cell Impedance Based Sensing System for the Nanotoxicity Assay

The integration of nanomaterials and biotechnology is widely utilized and has great potential in rapidly developing fields such as biomedical engineering research, drug delivery, environmental health, pharmaceutical industries and even electronics and communication technologies. With this rapid development, questions have arisen whether the use of these new nanoscale materials (including nanotubes, nanowires, nanowhiskers, fullerenes or buckyballs, and quantum dots) might have unintended human health hazards. In this paper, we describe an electrical impedance measuring biosensor that can perform cytotoxicity assays of gold, silver cadmium oxide and carbon nanotubes (multi-walled and single-walled) on human lung fibroblasts with a shorter run time, easier performance and more precise results than previous methods. By measuring the resistance change when cells attach to the electrodes on the biosensing chip, toxicity levels of the various materials were recorded. Our method was successful in measuring the known toxic effects of cadmium oxide as well as the unexpected toxicity of silver in the small range of size (10 nm) within a much shorter time frame of 40 hours compared to 24 to 96 hours of current the biological methods.