Nanoparticles of Waste Material of Propolis and Gelatin as a Novel System for Delivery of L-Ascorbic Acid

Background: The waste material from the preparation of propolis extracts is a potential natural compound for application in pharmaceutical and medicine nanostructured products. Ascorbic acid is an excellent antioxidant and an important cofactor of several physiological and biochemical processes. Objective: The aim of this study was to develop and characterize nanoparticles containing L-ascorbic acid prepared with propolis byproduct. Method: Nanoparticle's physicochemical characteristics (surface morphology, particle size, zeta potential, and entrapment efficiency), antioxidant activity, in vitro release profile, and in vitro cytotoxicity were evaluated. Results: Nanoparticles showed to be spherical, with agglomeration, mean diameter between 110.93 and 480.59 nm, zeta potential near zero and good entrapment efficiency. Antioxidant activity of L-ascorbic acid increased when nanoencapsulated and the drug release was prolonged, controlled mainly by the phenomenon of relaxation of polymer chains and dependent of propolis residue concentration. The application of technology provided a reduction in the level of cytotoxicity of L-ascorbic acid, and the nanoparticles showed a protective effect on macrophages.