Assessment of Minimal Amounts of Sample Useful for Pharmaceutical Actives and Early Stage Formulations

The 2005 AAPS Annual Meeting & Exposition saw the US launch of new accessories for Freeman Technology's FT4 Powder Rheometer. Leading these is the fully automated, small volume shear cell which can be used to measure volumes down to 3 ml or less, depending on the characteristics of the powder. This completely new module enables users to extend the range of shear testing applications on the FT4 to include those for which only very small amounts of sample are available. This encompasses many pharmaceutical actives, and materials, such as early stage formulations, where a wide range of tests must be carried out on limited supplies.

The FT4 is a universal powder rheometer that is used to conduct an array of powder flowability tests. These provide a means to characterize the flow properties of powder materials and relate them to performance in process. Where shear testing is required to complement flowability data, both the new small volume shear cell and the existing standard shear cell accessory offer significant advantages over conventional methods.

Shear testing using the FT4 is fully automated, minimizing operator involvement for greater repeatability and reproducibility of results. And it is fast, with tests completed in around 40 minutes. Measurements can be made at low levels of material consolidation, thanks to the system's high sensitivity, and over a wide range of stresses up to 100 kPa, allowing simulation of many different packing conditions. Conditioning of material before testing ensures homogeneity and a high degree of repeatability.