Capacitive biosensor for nanotoxicity detection

Nanomaterials (NMs) are widely used in health and biomedical applications, however, only a few studies investigated their toxic effects. Here, we have developed a capacitive biosensor to detect toxic effects of NMs using whole E. coli cells as biological reporters and gold nanoparticles (AuNPs) as models. The results showed that capacitive response was dependent on the size of nanoparticles. The toxic effect of nanoparticles was also studied using attenuated total reflection-fourier transform infrared (ATR-FTIR) spectra and scanning electron microscopy (SEM). Our results showed that it is possible to detect toxic effects of nanoparticles on E. coli cells by the developed capacitive biosensor. The toxic effects is attributed to the damage of the cells' outer membrane in combination with AuNP's byproducts, such as free radicals and reactive oxygen species (ROS) entering the cells. The methodology developed has a great potential to be applied in nanotechnology for classifying toxic and non-toxic NMs. (C) 2012 Elsevier Elsevier Ltd....Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.