Observation of two-dimensional yttrium oxide nanoparticles in mealworm beetles (Tenebrio molitor)

Assessment of Toxicity of Nanoparticles Using Insects as Biological Models

Nanomaterials have become increasingly important in medicine, manufacturing, and consumer products. A fundamental understanding of the effects of nanoparticles (NPs) and their interactions with biomolecules and organismal systems has yet to be achieved. In this chapter, we firstly provide a brief review of the interactions between nanoparticles and biological systems. We then provide an example by describing a novel method to assess the effects of NPs on biological systems, using insects as a model. Nanoparticles were injected into the central nervous system of the discoid cockroach (Blaberus discoidalis). It was found that insects became hyperactive compared to negative control (water injections). Our method could provide a generic method of assessing nanoparticles toxicity.

High resolution fluorescence bio-imaging upconversion nanoparticles in insects

Imaging fluorescent markers with brightness, photostability, and continuous emission with auto fluorescence background suppression in biological samples has always been challenging due to limitations of available and economical techniques. Here we report a new approach, to achieve high contrast imaging inside small and difficult biological systems with special geometry such as fire ants, an important agricultural pest, using a homemade cost-effective optical system. Unlike the commonly used rare-earth doped fluoride nanoparticles, we utilized nanoparticles with a high upconversion efficiency in water. Specifically Y₂O₃:Er⁺³,Yb⁺³ nanoparticles (40-50 nm diameter) were fed to fire ants as food and then a simple illuminating experiment was conducted at 980 nm wavelength at relatively low pump intensity8 kW.cm^-2. The locations were further confirmed by X-ray tomography, where most particles aggregated inside the ant's mouth. High resolution, fast, and economical optical imaging system opens the door for studying more complex biological systems.