Pharmaceutical Powders: Small Sample Sizes Yield Big Results

Pharmaceutical powders are expensive in all aspects, from initial definition through development to final product. The prohibitive costs involved with pharmaceutical powders translate to small sample sizes needed to define powder flow characteristics such as flow function, bulk density and arching dimension. Being able to measure these parameters is a must to ensure proper handling, dispensing and storage of these materials.

Small sample sizes are usually all that is available to define these necessary characterization tests. This is a double-edged sword. Most powder test methods need large sample sizes on the order of hundreds of cc’s to run these tests. So the producer must make these large volumes of sample powder available for testing, or risk the other edge of the sword: downstream powder jams, equipment lock-up and costly downtime until these problems can be sorted out, characterized, defined and solved. The other choice is to produce small volumes of product and run sample tests using methods such as flow cup, angle of repose, and tap test (Carr Index or Hausner Ratio) which do not give a direct correlation with flow behavior.

Brookfield Engineering has answered the needs of the pharmaceutical industry by producing a reliable test method for handling small volumes of pharmaceutical powders. With the introduction of the small volume shear cell for its popular Powder Flow Tester, powder sample volumes needed for testing have been reduced from 263cc to a mere 43cc.