Carboxymethyl gum kondagogu: Synthesis, characterization and evaluation as mucoadhesive polymer

► Carboxymethylation of gum kondagogu reduces its viscosity, improves bioadhesion and ionic gelation. ► Metformin-loaded beads were prepared by ionic gelation with Ca2+. ► Beads released the drug by Fickian-diffusion following zero-order release kinetics. ► Beads showed ex vivo bioadhesion of >80% over 24 h.