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Pharmaceutics 2018, 10(2), 49;

Inline Determination of Residence Time Distribution in Hot-Melt-Extrusion

Institute of Solids Process Engineering, TU Dortmund University, Dortmund 44227, Germany
ColVisTec AG, Berlin 12489, Germany
Author to whom correspondence should be addressed.
Received: 28 February 2018 / Revised: 29 March 2018 / Accepted: 11 April 2018 / Published: 15 April 2018
(This article belongs to the Special Issue Pharmaceutical Applications of Hot-melt Extrusion)
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In the framework of Quality-by-Design (QbD), the inline determination of process parameters or quality attributes of a product using sufficient process analytical technology (PAT) is a center piece for the establishment of continuous processes as a standard pharmaceutical technology. In this context, Twin-Screw-Extrusion (TSE) processes, such as Hot-Melt-Extrusion (HME), are one key aspect of current research. The main benefit of this process technology is the combination of different unit operations. Several of these sub-processes are linked to the Residence Time Distribution (RTD) of the material within the apparatus. In this study a UV/Vis spectrophotometer from ColVisTec was tested regarding the suitability for the inline determination of the RTD of an HME process. Two different measuring positions within a co-rotating Twin-Screw-Extruder were compared to an offline HPLC–UV as reference method. The obtained results were overall in good agreement and therefore the inline UV/Vis spectrophotometer is suitable for the determination of the RTD in TSE. An influence of the measuring position on repeatability was found and has to be taken into consideration for the implementation of PATs. An effect of the required amount of marker on process rheology is not likely due to the low Limit-of-Quantification (LoQ). View Full-Text
Keywords: UV/Vis spectroscopy; Residence Time Distribution; twin screw extrusion; process analytical tool; Quality-by-Design UV/Vis spectroscopy; Residence Time Distribution; twin screw extrusion; process analytical tool; Quality-by-Design

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This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

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Wesholowski, J.; Berghaus, A.; Thommes, M. Inline Determination of Residence Time Distribution in Hot-Melt-Extrusion. Pharmaceutics 2018, 10, 49.

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