To support R&D work for the blending of DPI (dry powder inhaler) formulations, Hosokawa Micron has developed the Mini Cyclomix lab mixer.
Based on the established Cyclomix high shear blending technology, the Mini Cyclomix has many key features that add benefits in the development of pharmaceutical powders.
Blending formulations for DPIs is a delicate matter since a fully homogeneous blend must be delivered without deterioration of the particles. To disperse the actives in the lactose, the cohesive forces between the fine particles need to be broken, requiring a certain amount of mechanical energy. If too much energy is applied, however, adhesive forces between the carrier and the actives will be too high, limiting the separation during inhalation. Finding the right balance for the required mixing energy is therefore a critical issue and calls for an efficient mixer.
The Mini Cyclomix supports exchangeable product bowls of 100ml, 1 litre, or 2 litres, which are connected to the drive unit by a bayonet ring without any special tools. Because these bowls are detachable, they can be filled and discharged in a separate location such as a dispensary or a glovebox.
The unit is operated from an integrated touch panel. It features straightforward recipe management, data logging and data export.
The large surface area, in relation to the product volume, makes the Mini Cyclomix a very efficient mixer compared with other high shear blenders, resulting in a homogeneous blend with a minimum input of mechanical energy, the company says.
Because of the adjustable mixing speed and time the Mini Cyclomix is able to perform other processes such as coating, bonding, rounding or densification.
The mixer uses a combination of impact and shear mixing. The product is rotated by an agitator with paddles and a knife blade. The rotational movement applies centrifugal forces on the powder particles which move the particles upwards along the wall of the conical vessel. At the top of the cone, the specially formed dome guides the particles downwards again through the centre of the vessel. This flow-pattern is combined with a rotational pattern.