Abstract: Drosophila melanogaster, a.k.a. the common fruit fly, is a simple organism that may give a rapid, high-throughput response in regard to the therapeutic efficacy of nanoparticles and drugs, while circumventing the high environmental and monetary cost of today’s typical in vivo assays involving more complex animals, along with the immeasurable suffering imposed onto them. Here we give the progress report on our effort to turn D. melanogaster into a model organism for the in vivo testing of Blood-Brain Barrier (BBB) penetration of nanoparticles and the treatment of infectious disease. We show that orally ingested superparamagnetic nanoparticles successfully cross the BBB in D. melanogaster and localize to the optic lobes of the third instar larval brain, while causing no adverse effects to the invertebrate organisms. We also show that both orally ingested calcium phosphate nanoparticles and biofilm-forming P. aeruginosa localize to the Drosophila crop, the food storage organ of the fly, which shrinks in response to infection. The model does not induce mortality consequential to infection and the effects of the internalization and proliferation of the microbes are evaluable by measuring the crop parameters, including fluorescence intensity and size. Continued development of these two models could simplify the preclinical testing of medical treatments and of pharmaceutical agents for neurological and infectious disease, while ensuring robust and reliable levels of statistical significance at low cost.

Key words: animal model, calcium phosphate, in vivo, iron oxide, nanoparticle