Investigation of Segregation Effects in a Direct Compaction Process Via Multipoint NIR Monitoring and NIR Chemical Imaging

During the last years the application of near-infrared spectroscopy (NIRS) has become an established technology for in-line process monitoring of the API-content, as it is a fast and non-destructive method. Common methodologies have been further developed to multipoint applications allowing the timely aligned assessment of real time process data from different positions or even processes. Additionally, hyperspectral imaging (HSI) even allows measuring not only parts of powder streams or single tablets, but a large number of tablets. Even mapping of each single tablet becomes feasible and enables detection of API agglomerations.

 

In this study the evolution of API concentration within a direct compaction process is monitored in-line by means of a multipoint spectrometer using separate fibres at different locations within the press. In addition, a HSI unit assesses the quality of the final tablets. This approach enables the determination of content uniformity along the powder path and therefore, investigation of segregation effects along the processing route. Goal of the work is the evaluation, if those effects influence the final product quality and if different operating conditions affect the extent of segregation.