The cytotoxic and antimicrobial impact of Metallic Nanoparticles on an in-vitro human GI tract model.

K. Sheehy, A. Murphy, N. O’Claonadh, A. Casey, G. Chambers
Dublin Institute of Technology, IE

Keywords: toxicity, gastro-intestinal tract, oral, composites, nanofood

Summary:

Metallic nanoparticles such as zinc oxide and nano-silver have been shown to display antimicrobial effects which have lead to their application in polymer composite for use in food contact materials (FCM). This study will present evidence which suggests that leached nanoparticles from the composites could induce a toxic response in-vitro and affect the intestinal microbiota. Composites consisting of the aforementioned nanoparticles and polyethylene were formed and a leaching study was performed. The leached concentrations were subsequently used to mimic real-world exposures for the exploration of both the cytotoxic and antimicrobial effects of the particles in an in-vitro model of the human GI-tract. For all assays studied the direct exposure of the nanoparticles to both cell lines was seen to elicit significant toxicity. The mechanism of toxicity will be discussed in terms of the formation of reactive oxygen species. Finally bacterial growth rates of lactic acid bacteria in the presence of the nanoparticles, will be discussed. The results indicated a significant reduction in the growth rate of each species tested in the presence of the nanoparticles. The implications of the work will be discussed in terms of the use nano-enhanced composites for food packaging.