Pontos quânticos de carbono funcionalizados com curcumina: eficácia fotodinâmica em larvas de Aedes aegypti

Abstract

Arboviruses transmitted by Aedes aegypti remain a major public health challenge, and vector control based on chemical insecticides faces limitations related to efficacy, resistance, and environmental impact. In this context, it is relevant to develop aqueous photosensitizers selective for the larval stage of the vector. This work aimed to synthesize, characterize, and compare pristine carbon quantum dots (CQ-Dots) and curcumin-loaded carbon quantum dots (CQD-Cur) regarding their potential for photodynamic control of 3rd-instar A. aegypti larvae. CQ-Dots were obtained via a microwave-assisted bottom-up route using dextrose as a carbon precursor and subsequently functionalized with curcumin to yield CQD-Cur. The samples were characterized by UV-Vis absorption, fluorescence spectroscopy, FTIR, dynamic light scattering, zeta potential, and atomic force microscopy; confocal microscopy in Artemia sp. and A. aegypti larvae was used to assess internalization. Ecotoxicity assays in Artemia sp. and photodynamic tests under RGB LED and sunlight irradiation allowed correlation of physicochemical properties, reactive oxygen species generation (ROS), and larval mortality. Results indicate that both systems generate ROS and accumulate in the digestive tract, but only CQD-Cur promotes significant photoinactivation of the larvae, without a marked increase in dark toxicity. These findings suggest that curcumin-functionalized carbon quantum dots constitute a promising and potentially more sustainable approach to complement the integrated management of A. aegypti populations.