Evaluation of antiparasitic effect of silver nanoparticles against Trypanosoma cruzi in vitro

American trypanosomiasis is one the globally neglected tropical disease, and is cause by the protozoan haemoflagellate Trypanosoma cruzi (Tc). Currently, the anti-Tc drugs are limited and no vaccine is available. The objective of the study was to determine the effects of silver nanoparticles (AgNPs) against trypomastigotes of the Sylvio X10/4 (TcI) and Esmeraldo (TcII) strains. The AgNPs were obtained by the reduction method and a structural characterization was carried out. The cytotoxic activity of the AgNPs (antiTc activity) was determined by calculating the values of half the maximum inhibitory concentration (IC50) in HaCaT cells and parasites. AgNPs showed no-cytotoxicity against HaCaT cells at the IC50 values assayed in parasites, and the calculated IC50 trypomastigotes was 4.05 & mu;g/ml and 6.16 & mu;g/ml for TcI and TcII strains, respectively. AgNPs were more active against both Trypanosoma cruzi strains than nifurtimox (400 & mu;g/ml) in vitro assays. These results lay the groundwork for further evaluation of AgNPs, to investigate its chemotherapeutic value to figh T. cruzi infection in animal models.