Colin M. Keary

Preliminary Report of the Discovery of a New Pharmaceutical Granulation Process Using Foamed Aqueous Binders

Spray granulation is commonly used to improve the flow of drug formulation powders by adding liquid binders. We have discovered a new granulation process whereby liquid binders are added as aqueous foam. Initial experiments indicate that foam granulations require less binder than spray granulations, less water is added to the powder mass, rates of addition of foam can be greater than rates of addition of sprayed liquids, and foam can be added in a single batch to the surface of the powder mass for incorporation at some later stage in the process. This new process appears to have no detrimental effects on granulate, tablet, or in vitro drug dissolution properties. In addition, the elimination of spray addition reduces the complexity of the process and avoids the plugging problems associated with spray nozzles. Several formulations were successfully scaled up from laboratory scale (1.5 kg) to pilot scale (15 kg). Process control was good and there was no detrimental effect on tablet and drug dissolution properties. This paper also proposes a working hypothesis of the mechanism by which foam granulation operates.

Wet film dimensions of capsule walls during dip coating.

ABSTRACT The objective of the present study was to improve our understanding of the relationships between wet film dimensions, dip sequences, and the physico-chemical properties of the dip solutions as they pertain to the dip-coating process for the manufacture of hard-shell capsules. To achieve this objective, it was necessary to develop a technique to quantify wet film dimensions. A further objective was to develop a predictive model for dip coating with hydroxypropyl methylcellulose (HPMC) solutions. It is hoped that the information contained in this article on significant variables controlling wet film thickness will help manufacturers develop consistent manufacturing controls and processes.