<em>Daphnia magna</em> and<em> Xenopus laevis</em> as in vivo models to probe toxicity and uptake of quantum dots functionalized with gH625

Abstract

The use of quantum dots (QDs) for nanomedicine is hampered by their potential toxicologic effects and difficulties with delivery into the cell interior. We accomplished an in vivo study exploiting <i>Daphnia magna</i> and <i>Xenopus laevis</i> to evaluate both toxicity and uptake of QDs coated with the membranotropic peptide gH625 derived from the glycoprotein H of herpes simplex virus and widely used for drug delivery studies. We evaluated and compared the effects of QDs and gH625-QDs on the survival, uptake, induction of several responsive pathways and genotoxicity in <i>D. magna</i>, and we found that QDs coating plays a key role. Moreover, studies on <i>X. laevis</i> embryos allowed to better understand their cell/tissue localization and delivery efficacy. <i>X. laevis</i> embryos raised in Frog Embryo Teratogenesis Assay-<i>Xenopus</i> containing QDs or gH625-QDs showed that both nanoparticles localized in the gills, lung and intestine, but they showed different distributions, indicating that the uptake of gH625-QDs was enhanced; the functionalized QDs had a significantly lower toxic effect on embryos' survival and phenotypes. We observed that <i>D. magna</i> and <i>X. laevis</i> are useful in vivo models for toxicity and drug delivery studies.