The Toxic Effects of Quantum Dots on Embryogenesis in Caenorhabditis elegans

Quantum dots have the potential to be used in medical applications such as tumor targeting and directed drug delivery. Their high molecular brightness, tunable emission spectra and photostability are just a few of the properties that make these nano-sized semiconductor particles attractive candidates for such applications. However, before quantum dots can be employed for therapeutic or diagnostic purposes, their potential toxicity needs to be thoroughly investigated. Such toxic effects may arise from their size or from the inherent toxicity of the materials that make up their core. In this study, the toxic effects of quantum dots on embryogenesis have been explored using the Caenorhabditis elegans (C. elegans) embryo as a model organism. Quantum dots are introduced into this nematode by microinjection and are then incorporated into its developing oocytes. Preliminary results suggest that the level of toxicity on embryo development is strongly dependent on the composition of the nanoparticles, on its coating, and on its propensity to aggregate. Additionally, it has been observed that the embryo uses a technique to package the quantum dots into isolated aggregates during development. The dynamic behavior of quantum dots in the C. elegans oocyte has also been studied using fluorescence correlation spectroscopy.