By Sharon Nowak, Global Business Development Manager, K-Tron Process Group
As seen in The Pharmaceutical Solutions Update, 2008 Fall Edition
As the development and demands for continuous processing continue to grow in the pharmaceutical industry, the requirements for increasingly lower feed rates at extremely high accuracies also is growing. Accurately and reliably controlling any powder flow can be a challenge. In addition, the requirements for minimal product loss at higher yields when dealing with feeding of laboratory devices or micronizers is a critical concern. The lower overall rates coupled with minimal residual requirements by today's pharmaceutical processes have caused both feeder and drug manufacturers to re-evaluate overall feeding design and performance.
Active pharmaceutical ingredients (APIs) and excipients alike now can be delivered at rates as low as 20 g/hr while achieving high-precision feeding with minimal sample-tosample variation. Microfeeding of powders, defined as feed rates of less than 2 kg/hr, differs considerably from feeding at higher rates. This article will explain these differences and define the obstacles that must be overcome in microfeeding system design for pharmaceutical applications. In addition, the various applications for microfeeding will be explored, and the critical parameters for properly selecting a microfeeder and evaluating its performance will be defined. Background Spurred by the pharmaceutical.