Development of Brazil nut oil microemulsion as vehicle for Levamisole

Abstract

Brazil nut (Bertholletia excelsa H. B. K.) is one of the most valuable national Lecythidaceae from Brazil, collaborating with local economy. Besides being rich in nutrients, it has high content of unsaturated fatty acids, proteins and vitamins. On the other hand, levamisole (LMS) is a synthetic imidazothiazole derivative mostly used as agent in anthelmintic treatment; however it is reported to have issues in its oral bioavailability. Microemulsion (ME), immiscible liquids stabilized by surfactants, is a promising bioavailability enhancer nowadays by modifying the release of active ingredient at its site of action, reducing therapeutic dosage with consequent side effects, and increasing absorption of natural ingredients. So, the development of a stable ME containing Brazil nut oil to carry LMS can be a promising pharmaceutical form in this drug therapeutic efficiency behalf. For that, it was developed a stable oil-in-water ME which held pH, conductivity, and refractive index along the study, presenting satisfactory stability under long-term stress conditions. Its particle size is classified as nanostructure (33,35nm), and rheological parameters confirmed a Newtonian behavior, with constant viscosity. The Brazil nut oil ME can be an alternative as adjuvant in pharmaceutical forms and a promising upgrading tool to carry LMS, improving its therapy.