Evaluation of carboxymethyl gellan gum as a mucoadhesive polymer

► Carboxymethyl gellan was synthesized by William synthesis. ► Carboxymethylation increases degree of crystallinity, surface roughness. ► Improvement in mucoadhesion and diminished sensitivity to cation-induced gelation. ► Ionically gelled beads of metformin-loaded carboxymethyl gellan were formulated. ► Cytotoxicity study on Vero cells revealed biocompatibility of carboxymethyl gellan.