The Use of PAT and Off-line Methods for Monitoring of Roller Compacted Ribbon and Granule Properties with a View to Continuous Processing 

Granulation is the process of adhering or agglomerating primary particles into larger granulates. Roller compaction is the only method of dry granulation that is employed by the pharmaceutical industry today. Dry granulation as the name suggests is the granulation of powder without the addition of a liquid binder. Dry granulation relies on compacting and densifying powders under high pressure in order to from granulates. Roller compaction uses an auger-feed system that delivers powder uniformly between two pressure rollers. The powder is compacted into a ribbon between these rollers prior to milling through a low-shear mill. Uniform density across the ribbon is critical to achieving granules with a uniform particle size distribution. 

Real-time process monitoring using process analytical technology (PAT) tools can augment process understanding, enable improved process control, and hence facilitate the production of high-quality pharmaceutical products. While beneficial for batch processes, the availability of PAT tools to monitor continuous processes in real time is required to ensure product quality. The Multieye™ is a multi-point NIR device that can be used to monitor ribbon density and is highly applicable as a method of process analytic technology to roller compaction.

This paper presents the application of novel PAT tools in combination with off-line analytical techniques for the study of a laboratory-scale roller compaction dry granulation process. An experiment whereby roll pressure was linearly increased and the effects thereof on roller compacted ribbon and granule properties of a placebo formulation is described.