Influence of the process of obtaining retrograded starch/pectin microparticles by ionotropic gelation and coating with cellulose nanofibers on the targeting of 5-ASA to the colon.

Abstract

Inflammatory Bowel Disease (IBD) is a group of pathologies that cause chronic inflammation of the gastrointestinal tract (GIT). The treatment of choice for IBD is performed with the drug 5-ASA, which acts on the colon mucosa by reducing inflammation. 5-ASA is rapidly absorbed in the upper portions of the GIT, causing only 20% of the administered dose to reach the colon. Some systems are used for the vectorization of 5-ASA, such as the use of prodrugs, pH-dependent systems, time-dependent systems, and systems activated by colonic microbiota. Given the strategies mentioned, it is possible to use biodegradable polysaccharides that are degraded by enzymes secreted by the colonic microbiota to develop colon-specific release systems (SLOCs) and vectorize the drug directly to the colon. Retrograded starch (RS) is a starch modified by hydrothermal treatments and, together with pectin, a polysaccharide with mucoadhesive properties, has potential for the development of new SLOCs, making 5-ASA have a higher rate of vectorization to the colon. However, pectin has high aqueous solubility, which makes it difficult to resist in different parts of the GIT. Thus, coating with cellulose nanofiber (NFC) leads to reinforcement of the AR/P blend, as it hinders rehydration with gastrointestinal fluids and prolongs release rates. Therefore, the objective of this research project is the development of AR/P microparticles coated with NFC for the vectorization of 5-ASA to the colon in the treatment of IBD. System characterization and validation of methodologies will be carried out, as well as in vitro assays to prove the effectiveness of the proposed system.