Tissue-specific direct microtransfer of nanomaterials into Drosophila embryos as a versatile in vivo test bed for nanomaterial toxicity assessment

Sasha Vega-Alvarez,¹ Adriana Herrera,² Carlos Rinaldi,^2–4 Franklin A Carrero-Martínez<sup>1,5

1</sup>Department of Biology, ²Department of Chemical Engineering, University of Puerto Rico-Mayagüez, Mayagüez, Puerto Rico; ³J Crayton Pruitt Family Department of Biomedical Engineering, ⁴Department of Chemical Engineering, University of Florida, Gainesville, FL, USA; ⁵Department of Anatomy and Neuroscience, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico

Abstract: Nanomaterials are the subject of intense research, focused on their synthesis, modification, and biomedical applications. Increased nanomaterial production and their wide range of applications imply a higher risk of human and environmental exposure. Unfortunately, neither environmental effects nor toxicity of nanomaterials to organisms are fully understood. Cost-effective, rapid toxicity assays requiring minimal amounts of materials are needed to establish both their biomedical potential and environmental safety standards. Drosophila exemplifies an efficient and cost-effective model organism with a vast repertoire of in vivo tools and techniques, all with high-throughput scalability and screening feasibility throughout its life cycle. Here we report tissue specific nanomaterial assessment through direct microtransfer into target tissues. We tested several nanomaterials with potential biomedical applications such as single-wall carbon nanotubes, multiwall carbon nanotubes, silver, gold, titanium dioxide, and iron oxide nanoparticles. Assessment of nanomaterial toxicity was conducted by evaluating progression through developmental morphological milestones in Drosophila. This cost-effective assessment method is amenable to high-throughput screening.

Keywords: nanotoxicity, Drosophila, microtransfer, nanoparticle, iron oxide, silver, gold, titanium dioxide, carbon nanotube