Carbon Nano-Onions as Nontoxic and High-Fluorescence Bioimaging Agent in Food Chain-An In Vivo Study from Unicellular E. coli to Multicellular C-elegans

Carbon nano-onions, as a newly-emergent member of the carbon family, have attracted attention in its both dry and wet applications. Here we report in vivo effects of water-soluble carbon nano-onions (wsCNOs) introduced in common food web of two model organisms: unicellular Escherichia coli (E. coli) and multicellular Caenorhabditis elegans (C. elegans). At first, CNOs are fed to E. coli and, subsequently, the E. coli are fed to C. elegans. It is found that wsCNOs serve as highly-fluorescent bioimaging agent. The results do not reflect any toxic effect of wsCNOs on the growth of these organisms suggesting new avenues in nanotoxicology research and biomedical application including drug delivery.