Compaction characteristics of ethylcellulose in the presence of some channeling agents: Technical note

Summary and Conclusion

This study investigated the effect of some commonly used release enhancers on the compaction characteristics of EC. The wet granulation method of massing and screening was used, and compacts were produced by compressing granules for 60 seconds at various compression pressures. The Heckel equation, used for the analysis of results, showed that EC alone showed better compressibility than formulations with additives. The hygroscopic additives, sorbitol and PEG 4000, produced unusual Heckel plots, while the nonhygroscopic additives, PEG 10 000 and mannitol, produced biphasic Heckel plots. The results also indicate that EC alone exhibited the highest degree of packing in the die, with the addition of mannitol reducing the extent of packing the most. The presence of additives in EC for-mulations increased the pressures at which plastic deformation of EC granules occurred. The extent of this depended on the type of additive, with mannitol imparting the highest resistance to deformation of EC granules and sorbitol the lowest. It can be concluded that additives such as PEG 4000, PEG 10 000, sorbitol, and mannitol, which are often used as channeling agents in sustained-release formulations containing hydrophobic matrix formers, affect the deformation characteristics of EC, with the extent and nature of the effect dependent on the nature of the additive.