Enhancement of niacin availability in the ileocolonic region by microencapsulation and coating

In the recent past, the human gut microbiota has gained increasing interest as a target for the delivery of substances due to the observed interaction between the microbiome, nutrition and health. The water-soluble vitamin niacin showed first effects on the composition of the gut microbiota. In order to enhance the availability of niacin in the ileocolonic region, where most of the microorganism are located, an early systemic absorption of niacin in the stomach and small intestine must be prevented. Therefore, two active forms of niacin (nicotinic acid (NA) and nicotinamide (NAM)) were encapsulated by a protective shellac coating applied via fluidized bed coating. The modulation of the release profile of niacin was assisted by a newly designed in vitro dissolution test and verified by a human bioavailability study with 10 healthy volunteers for each group. Different intrinsic effects on the release profile such as derived from the properties of the encapsulated compound were investigated. The active substance core was produced by a one-step spray granulation and a two-step process (extrusion with subsequent spheronisation). The latter method achieved a higher particle yield and required a lower use of shellac in relation to the mass of active substance. As an alternative to shellac coated microcapsules, the incorporation of niacin into pectin-zein hydrogel beads was characterized. A precise targeted release of niacin into the ileocolonic region in vitro and in vivo was reached by using a shellac based coating with adapted intermediate subcoatings consisting of either citric acid for NAM or sodium bicarbonate of NA. The subcoatings were able to control the effect of the physico-chemical properties of the encapsulated compound and to influence the pH-dependent dissolution of the surrounding shellac coatings. The designed in vitro dissolution test for the targeting provided a precise instrument to predict the release behavior in humans

Modelling the Effect of Process Parameters on the Wet Extrusion and Spheronisation of High-Loaded Nicotinamide Pellets Using a Quality by Design Approach

Open access articleThe aim of the present study was to develop an alternative process to spray granulation in order to prepare high loaded spherical nicotinamide (NAM) pellets by wet extrusion and spheronisation. Therefore, a quality by design approach was implemented to model the effect of the process parameters of the extrusion-spheronisation process on the roundness, roughness and useable yield of the obtained pellets. The obtained results were compared to spray granulated NAM particles regarding their characteristics and their release profile in vitro after the application of an ileocolon targeted shellac coating. The wet extrusion-spheronisation process was able to form highly loaded NAM pellets (80%) with a spherical shape and a high useable yield of about 90%. However, the water content range was rather narrow between 24.7% and 21.3%. The design of experiments (DoE), showed that the spheronisation conditions speed, time and load had a greater impact on the quality attributes of the pellets than the extrusion conditions screw design, screw speed and solid feed rate (hopper speed). The best results were obtained using a low load (15 g) combined with a high rotation speed (900 m/min) and a low time (3–3.5 min). In comparison to spray granulated NAM pellets, the extruded NAM pellets resulted in a higher roughness and a higher useable yield (63% vs. 92%). Finally, the coating and dissolution test showed that the extruded and spheronised pellets are also suitable for a protective coating with an ileocolonic release profile. Due to its lower specific surface area, the required shellac concentration could be reduced while maintaining the release profil

Ružička days : International conference 16th Ružička Days “Today Science – Tomorrow Industry” : Proceedings

Proceedings contains articles presented at Conference divided into sections: open lecture (1), chemical analysis and synthesis (3), chemical and biochemical engineering (8), food technology and biotechnology (8), medical chemistry and pharmacy (3), environmental protection (11) and meeting of young chemists (2)