Synthesis, Characterization, and Activity of Hydroxymethylnitrofurazone Nanocrystals against Trypanosoma cruzi and Leishmania spp.

Hydroxymethylnitrofurazone (NFOH) is a prodrug of nitrofurazone devoid of mutagenic toxicity, with in vitro and in vivo activity against Trypanosoma cruzi (T. cruzi) and in vitro activity against Leishmania. In this study, we aimed to increase the solubility of NFOH to improve its efficacy against T. cruzi (Chagas disease) and Leishmania species (Leishmaniasis) highly. Two formulations of NFOH nanocrystals (NFOH-F1 and NFOH-F2) were prepared and characterized by determining their particle sizes, size distribution, morphologies, crystal properties, and anti-trypanosomatid activities. Furthermore, cytotoxicity assays were performed. The results showed that the optimized particle size of 108.2 ± 0.8 nm (NFOH-F1) and 132.4 ± 2.3 nm (NFOH-F2) increased the saturation solubility and dissolution rate of the nanocrystals. These formulations exhibited moderate anti-Leishmania effects (Leishmania amazonensis) in vitro and potent in vitro activity against T. cruzi parasites (Y strain). Moreover, both formulations could reduce parasitemia (around 89–95% during the parasitemic peak) in a short animal model trial (Y strain from T. cruzi). These results suggested that the increased water solubility of the NFOH nanocrystals improved their activity against Chagas disease in both in vitro and in vivo assays.