Figure 9: Schematic of NaCMC mucoadhesive hydrogel on the mucosa. (Middle) In contact stage, an intimate contact between mucoadhesive gel matrix and mucus is formed. (Right) In consolidation stage, NaCMC polymer chains interpenetrate with mucus glycoprotein, carboxyl groups of NaCMC can bond with hydroxyl end groups of oligosaccharide side chains of mucus protein, providing a prolonged adhesion.