Galactomannan (from Gleditsia sinensis Lam.) and xanthan gum matrix tablets for controlled delivery of theophylline: In vitro drug release and swelling behavior

► Galactomannan from Gleditsia sinensis Lam. was mixed with xanthan gum. ► The binary mixtures were applied as sustained release materials in matrix tablets. ► In vitro release of theophylline from matrices showed anomalous transport mechanism. ► Synergistic interactions between polymers effectively retarded drug diffusion. ► G. sinensis galactomannan is potential as sustained material for controlled release.