Controlled Release Oral Delivery of Apigenin Containing Pellets with Antioxidant Activity

Background: Drug delivery of phytochemicals has gained interest recently due to their remarkable health effects. Apigenin, a plant flavonoid, has antioxidant, anti-inflammatory and anticancer activities but its delivery is challenging. It could be absorbed through the whole intestine, however, it has poor bioavailability due to its low aqueous solubility. In Europe, the daily intake was estimated to be as low as 3 ± 1 mg. Pellets offer several advantages such as improved bioavailability and various resultant drug release profiles can be obtained by simply mixing pellets with different coatings. Objective: The objective of our study was to develop a carrier system containing 20 mg apigenin thus enhancing intake and to offer reduction of oxidative stress which can cause inflammation in the intestine. Method: The apigenin powder was dispersed in aqueous solution of binding material and layered onto the inert cores in a fluidized bed apparatus. The layered cores were further coated with enteric polymers and the process parameters were optimized. Results: The prepared pellets met with the requirements and have good physical characteristic. 10% (w/w) Eudragit® L was suitable for enteric coating with a complete release at pH 6.8 within 1 hour. 15% (w/w) Eudragit® FS coating ensured acid resistance ability and colonic delivery. The therapeutic efficiency was confirmed with antioxidant activity measurement by using DPPH* assay. Conclusion: Enteric coated spheres allow targeted delivery into the intestine and colon thus reaching the main absorption site. Pellets were proved to be an optimal delivery system for apigenin thus providing enhanced apigenin intake. Keywords: Antioxidant activity, apigenin, colon drug delivery, Eudragit®. flavonoid, modified release, pellet.