Water-in-Water Emulsion as a New Approach to Produce Mesalamine-Loaded Xylan-Based Microparticles

The water-in-water emulsion method has been reported as a technique able to prepare microparticles without using harmful solvents. However, there are few reports showing the encapsulation of small molecules into microparticles produced within this technique. The probable reason relays on the rapid diffusion of these molecules from the discontinuous phase to the continuous phase. In the present study, xylan microparticles containing mesalamine were produced and the doubled crosslinking approach, used to promote higher encapsulation rates, was disclosed. To achieve this goal, a 23 full factorial design was carried out. The results revealed that all formulations presented spherical-shaped microparticles. However, at specific conditions, only few formulations reached up to 50% of drug loading. In addition, the new xylan-based microparticles formulation retained almost 40% of its drug content after 12 h of a dissolution assay likely due to the degree of crosslinking. Thus, the doubled crosslinking approach used was effective on the encapsulation of mesalamine and may pave the way to successfully produce other polysaccharide-based carriers for clinical use.