Desenvolvimento de nanocarreador à base de óleo de girassol com potencial leishmanicida

Abstract

Leishmaniasis is one of the world's major neglected diseases, caused by protozoa of the genus Leishmania spp. Its cutaneous form is characterized by lesions on the skin and mucous membranes that are difficult to heal. Its treatment is limited due to high toxicity, parasite resistance to drugs, high cost, and drug administration routes. In this context, nanotechnology appears promising, aiming to improve the efficacy and reduce the adverse effects of drugs, based on systems such as nanoemulsions and nanoemulsions. In addition, the growing interest in the investigation of new compounds of natural origin, such as phytol, a natural diterpene, and sunflower oil, as possible allies in this therapy. Given this, the present study aimed to develop sunflower oil-based nanocarriers containing phytol to evaluate their stability and physicochemical characteristics as a therapeutic alternative for leishmaniasis. To this end, using the phase inversion emulsification method, formulations with different concentrations of phytol (2.5%, 5%, 7.5%, and 10%) in the oil phase were prepared, with a 5% sunflower oil matrix, for the production of nanoemulsions. The nanoemulsions were obtained by adding the polymer poloxamer 407 to the aqueous phase, varying the concentrations from 5%, 10%, and 15%. The formulations that remained stable over 35 days were physically and chemically characterized by droplet size analysis, polydispersity index (PI), pH, Fourier transform infrared spectroscopy, and antioxidant activity testing using the DPPH assay. The results showed that the nanoemulsion with 2.5% phytol had an average droplet size of approximately 200 nm, a PDI of 0.230, and stability greater than 30 days. The nanoemulgel with 10% phytol and 15% poloxamer had droplets with an average size of 374 nm, an IPd of 0.345, and also demonstrated prolonged stability for both the system with and without the active ingredient. Thus, the developed nanocarriers revealed promising physicochemical properties as a strategy to combat leishmaniasis lesions.