more than 80% microbial inhibition and toxicity toward a broad array of bacteria. Carpio et al. (2012) studied the toxicity effects of PVK-GO nanocomposite onplanktonic microbial cells, E. coli, C. metallidurans B. subtilis and R. opacus, biofilms, and mammalian fibroblast cells (NIH 3T3). Their results showed that PVK-GO presented a stronger antimicrobial effect than pristine GO. They also found that the PVK-GO was significantly neutral toward the fibroblast cells, indicating a huge potential of the composite material in biomedical and industrial application