title: Studying nanotoxic effects of CdTe quantum dots in Trypanosoma cruzi.
abstract: Semiconductor nanoparticles, such as quantum dots (QDs), were used to carry out experiments in vivo and ex vivo with Trypanosoma cruzi. However, questions have been raised regarding the nanotoxicity of QDs in living cells, microorganisms, tissues and whole animals. The objective of this paper was to conduct a QD nanotoxicity study on living T. cruzi protozoa using analytical methods. This was accomplished using in vitro experiments to test the interference of the QDs on parasite development, morphology and viability. Our results show that after 72 h, a 200 μM cadmium telluride (CdTe) QD solution induced important morphological alterations in T. cruzi, such as DNA damage, plasma membrane blebbing and mitochondrial swelling. Flow cytometry assays showed no damage to the plasma membrane when incubated with 200 μM CdTe QDs for up to 72 h (propidium iodide cells), giving no evidence of classical necrosis. Parasites incubated with 2 μM CdTe QDs still proliferated after seven days. In summary, a low concentration of CdTe QDs (2 μM) is optimal for bioimaging, whereas a high concentration (200 μM CdTe) could be toxic to cells. Taken together, our data indicate that 2 μM QD can be used for the successful long-term study of the parasite-vector interaction in real time.
authors.affiliation: Setor de Entomologia Médica e Forense, Laboratório de Transmissores de Leishmanioses.
authors.forename: Cecilia Stahl
authors.initials: CS
authors.lastname: Vieira
authors.forename: Diogo Burigo
authors.initials: DB
authors.lastname: Almeida
authors.forename: André Alexandre
authors.initials: AA
authors.lastname: de Thomaz
authors.forename: Rubem Figueredo Sadok
authors.initials: RF
authors.lastname: Menna-Barreto
authors.forename: Jacenir Reis
authors.initials: JR
authors.lastname: dos Santos-Mallet
authors.forename: Carlos Lenz
authors.initials: CL
authors.lastname: Cesar
authors.forename: Suzete Araujo Oliveira
authors.initials: SA
authors.lastname: Gomes
authors.forename: Denise
authors.initials: D
authors.lastname: Feder
mesh_terms: D000818:Animals; D019187:Cadmium Compounds / Q000633:toxicity*; D002462:Cell Membrane / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D004249:DNA Damage / Q000187:drug effects*; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D051379:Mice; D046529:Microscopy, Electron, Transmission; D008933:Mitochondrial Swelling; D045663:Quantum Dots; D013691:Tellurium / Q000633:toxicity*; D014349:Trypanosoma cruzi / Q000187:drug effects* / Q000648:ultrastructure
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D013691:Tellurium; C028337:cadmium telluride