Mucoadhesive 4-carboxybenzenesulfonamide-chitosan with antibacterial properties

► Synthesis of mucoadhesive 4-carboxybenzensulfonamide-chitosan without a thiol group. ► High mucoadhesive and swelling properties of 4-CBS-chitosan in acid conditions. ► Antibacterial activity of 4-CBS-chitosan conjugates against Escherichia coli and Staphlyococcus aureus.