Influence of polytetrafluoroethylene on spheroid production by rotary processing

During rotary processing, material adhesion on the product chamber wall som etimes occurs. The wall of the chamber can be lined with a layer of polytet rafluoroethylene to reduce material adhesion. This study examined the influ ence of the polytetrafluoroethylene lining opt spheroid production using la ctase of two different mean particle sizes. The mean size of spheroids obta ined from runs conducted when the chamber wall was unlined and lined with p olytetrafluoroethylene were compared. The effect of the polytetrafluoroethy lene lining was only I,marginal for formulations containing Pharmatose 200M (lactose monohydrate). For Pharmatose 100M, larger spheroids were formed at equivalent moistening levels when the chamber wall was lined with polytetr afluoroethylene. The softer, low-friction surface and tron-stick properties of the polytetrafluoroethylene lining aid in protecting the more fragile m icrocrystalline cellulose:lactose 100M agglomerates from fragmentation enab ling them to grow comparatively larger than similarly produced spheroids wi thout a polytetrafluoroethylene lining.