Preliminary assessment of carrageenan as excipient for extrusion/spheronisation

The current study pursues the suitability of different types of carrageenan as a novel extrusion aid. The aim was to find out a suitable substitution to the commonly used microcrystalline cellulose (MCC). The types of kappa-carrageenan were found to be the most appropriate material and the required fraction to produce acceptable pellets in the formulation was determined. The investigation showed that 5% of kappa-carageenan was necessary to produce pellets without MCC. Similar formulations produced with MCC or kappa-carrageenan were compared with respect to size and shape of the pellets. kappa-Carrageenan required higher water content for the formation of pellets, but the formulation was more robust as the optimal range of water content was much broader. Hence, kappa-Carrageenan seems to be a suitable and promising extrusion aid. The study showed that the substitution of MCC by kappa-carrageenan in formulations is possible and the produced pellets were of high quality.