Avaliação do efeito da incorporação de ativo natural em diferentes tipos de nanopartículas sobre a atividade larvicida de Aedes aegypti (LINNAEUS, 1762)

The present study evaluated the mortality of Ae. aegypti exposed to nanocapsules (NC) and nanoemulsions (NE) incorporated with active piperine. Nanoparticles were prepared by nanoprecipitation method and characterized by Dynamic Light Scattering. Ae. aegypti larvae of late 3rd instar and early 4th instar were exposed to nanoparticles in different concentrations and mortality were verified every 24 hours for IC50 determination. The behavior of larvae submitted to the substances studied were analyzed. And external morphological alterations of larvae controls were also verified. Residual tests were performed to determine the larvicidal effect. NC had diameter of 187.4nm, PDI of 0.197nm and Zeta potential of -31.51mV. NE had diameter of 112nm, PDI of 0.116 and Zeta potential of -11.47mV. LC50 of non-nanoencapsulated piperine was 14.50ppm in 24 hours exposure, 6.05ppm in 48 hours and 5.48ppm in 72 hours. NE presented 22.8ppm (24h), 7.12ppm (48h) and 6.25ppm (72h) LC50. The NC LC50 of 34.8ppm (24h), 12.14ppm (48h) and 8.28ppm (72h). During the bioassays it was possible to observe alterations of Aedes aegypti larvae submitted to different treatments, such as lethargy, lack of mobility and decrease of body size. By the method of nanoprecipitation it was able to produce nanostructured systems, presenting the diameter of particles and Zeta potential suitable for the method. The analyzed substances LC50 presented significant differences. As nanoparticles and a piperine solution, they were considered promising as larvicidal agents. The nanocapsule is a nanoemulsion, in summary, more prolonged, compared to a nonnanoencapsulated Piperin. The larvae exposed to the tested substances presented behavioral differences and external morphology alteration, compared to larvae that were exposed to control