Article,
Studying nanotoxic effects of CdTe quantum dots in Trypanosoma cruzi
MEMORIAS DO INSTITUTO OSWALDO CRUZ, 106 (2): 158-165 (2011)
DOI: 10.1590/S0074-02762011000200007
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 nano toxicity 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 mu M 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 mu M
CdTe QDs for up to 72 h (propidium iodide cells), giving no evidence of
classical necrosis. Parasites incubated with 2 mu M CdTe QDs still
proliferated after seven days. In summary, a low concentration of CdTe
QDs (2 mu M) is optimal for bioimaging, whereas a high concentration
(200 mu M CdTe) could be toxic to cells. Taken together, our data
indicate that 2 mu M QD can be used for the successful long-term study
of the parasite-vector interaction in real time.
