Fabrication of gastric floating controlled release tablet based on konjac glucomannan

• Ball mill was an effective way to reduce the particle size of KF.
• KF-4 with 4 h treatment time using high energy ball mill exhibited a better floating property.
• KF-4 exhibited the best controlled-release profiling over 14 h compared with other groups.
• Hydrogelling layer of KF-4 prevented moisture into the inner which delayed the release of the drug.

This paper investigated the effect of ball-milling time on the structure, floating and controlled-release properties of konjac flour (KF). After 8 h of ball milling, the particle size of KF decreased from 152 μm to 19.8 μm. The structural change of KF was characterized by repose angle, GPC-MALLS, X-ray diffraction (XRD) and scanning electron microscope. The results indicated that longer ball-milling time lead to higher repose angle, lower molecular weight and coarser surface of KF. Compared with native KF, the 4 h ball-milled KF achieved the shortest floating lag time, the longest floating duration time and the best controlled-release properties when used as excipients in floating drug release system. The water distribution in tablets with different dissolution time was observed by Magnetic resonance imagining (Wolk and Dahan). For KF-4, the hydrogelling layer could prevent moisture into the inner in order to achieve the control release.