Microemulsions with Levamisole Delivery Systems as Novel Immunomodulating Agents with Potential for Amebiasis Therapies

The aim of this study was to develop microemulsion systems from biocompatible materials, characterize their properties by incorporating levamisole hydrochloride and evaluate their phagocytic and microbicidal activity after incubation with microemulsion. The microemulsions were formulated using distilled water, caprylic/capric triglyceride-Polymol 812^®, Sorbitan Oletado-Span 80^®, Polysorbate 80-Tween 80^® and 1-butanol. Pseudoternary diagrams were prepared, and the microemulsion diagram regions were delimited and pre-selected. The microemulsions were incorporated with levamisole hydrochloride. Rheological characterization, release profile via dissolution, hydrodynamic diameter and zeta potential measuremenrs preliminary and accelerated stability tests were performed. The activity of microemulsions incorporated with levamisole hydrochloride on leukocyte and amoebae interactions was analyzed by phagocytosis and microbicidal activity. The microemulsions incorporated with levamisole hydrochloride numbers 5, 9 and 10 were not approved in the centrifugation test. Thermal stability was maintained in 3 formulations, but only the microemulsion incorporated with levamisole hydrochloride number 6 presented a minimal change in viscosity and demonstrated efficiency dissolution of 95% after 20 minutes. There was an increase in phagocytosis and microbicidal activity when Entamoeba histolytica were incubated with microemulsions that had been incorporated with levamisole hydrochloride. The microemulsion for levamisole delivery may represent a possible neo-material alternative for amebiasis therapies or as an immunomodulating agent.