pH-sensitive microparticles for oral drug delivery based on alginate/oligochitosan/Eudragit® L100-55 “sandwich” polyelectrolyte complex

The kinetics of the swelling process and the release mechanisms of Coriandrum sativum L. essential oil from chitosan/alginate/inulin microcapsules

“…3b) the lowest values of the swelling degree were registered for the M Ch-Alg microcapsules because, for this pH value, the amino groups are still -NH 3 + protonated and therefore interact through electrostatic forces with the ionised carboxyl groups (-COO -) of alginate forming a Ch-Alg complex polyelectrolyte structure which inhibits the intrusion of water molecules into microcapsule. Similar results were reported by other researchers (Li et al, 2011;Č alija et al, 2013).…”

Oxaprozin-Loaded Lipid Nanoparticles towards Overcoming NSAIDs Side-Effects

“…So in order to create gastroresistent alginate-OCH microparticles, Čalija et al used an anionic copolymer, Eudragit® L100-55, to stabilize the alginate-OCH microparticles in acidic conditions, leading to a decreased drug release at gastric pH and sustained drug release at intestinal pH. These microparticles may be used for oral NSAIDs delivery due its pH sensitive capacities [54]. dimethacrylate as degradable crosslinker.…”

pH‐sensitive polyelectrolyte films derived from submicron chitosan/Eudragit® L 100‐55 complexes: Physicochemical characterization and in vitro drug release

“…It is soluble at pH above 5.5, and therefore, widely used as an enteric coating agent. The ability of EL to interact with CHs and form PECs under appropriate conditions was reported earlier …”

“…As cationic polymers, CHs are able to form PECs with polyanions of both natural (carboxymethylcellulose, xanthan, pectin, hyaluronic acid, and alginate) and synthetic origin (cross‐linked poly(acrylic acid) polymers and polymethacrylate copolymers) . CH‐based PEC films and particulate carriers exhibit mucoadhesivity, pH‐dependent swelling, and drug release . These properties depend not only on the type and characteristics of polyanion used but also on the functional characteristics of CH, such as molecular weight and degree of deacetylation …”