Cylindrical granules in the development of mesalazine solid formulations (â ): Physical properties, compression behaviors, and tableting performances.

Cylindrical granules have been employed in the pharmaceutical industry. However, to our knowledge, the study on the compressibility and tabletability of cylindrical granules has not been reported. This study aimed to explore the effects of the physical properties of cylindrical granules on the compression behaviors and the tableting performances, with mesalazine (MSZ) as a model drug. First, the six formulations of MSZ cylindrical granules were extruded by changing the ethanol proportion in the binder. Then, the physical characteristics of MSZ cylindrical granules were systematically studied. Subsequently, the compressibility and tabletability were evaluated using different mathematic models. It was worth noting that highly porous cylindrical granules possessed favorable compressibility and good tabletability due to the increased pore volume, reduced density, and decreased fracture forces. Finally, dissolution tests were conducted and highly porous granules showed higher dissolution rates than the less porous ones, but an opposite trend was observed for the corresponding tablets. This study proved the importance of physical properties in the tableting process of cylindrical granules and provided strategies to improve their compressibility and tabletability.

Cobalt immobilized on hydroxyapatite as a low-cost and highly effective heterogeneous catalyst for alkenes epoxidation under mild conditions.

Transition metal Co immobilized on hydroxyapatite with a loading of 0.05 wt% (denoted 0.05 wt% Co/HAP) could catalyze partial oxidation of cyclic alkenes, aromatic alkenes and aliphatic alkenes to yield epoxide products with excellent selectivity at 30 °C with O2 and iso-butyraldehyde as co-oxidant. The TOF value was as high as 6261 h-1 for epoxidation of cyclohexene. In addition, the prepared 0.05 wt% Co/HAP catalyst can be re-used at least 6 times without significant loss of catalytic activity and selectivity.