AAPS PharmSci

, 2:45 | Cite as

Direct pelletization in a rotary processor controlled by torque measurements. II: Effects of changes in the content of microcrystalline cellulose

  • Jakob Kristensen
  • Torben Schæfer
  • Peter Kleinebudde


In the present study we investigated the effect of changes in the content of microcrystalline cellulose (MCC) on a direct pelletization process in a rotary processor in which the liquid addition was terminated once a certain increase in torque was produced. Nine different mixtures of MCC and lactose with MCC contents varying from 10% to 100% (w/w) were pelletized using 6 different torque increase levels, and the changes in pellet characteristics were investigated. The pellet characteristics investigated were pellet shape, size, and size distribution as well as the water content of the pellets at the end of liquid addition. To produce spherical agglomerates with suitable characteristics in a reproducible way, a content of a least 20% (w/w) MCC was found necessary. Linear correlations were found between the MCC content and the water content and between the torque incraase and the water content, showing that the torque increase is suitable to control the process. A higher torque increase or a higher MCC content was found to increase the water content independently of each other.


Microcrystalline Cellulose Pellet Size Indobufen Friction Plate Binder Liquid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© American Association of Pharmaceutical Scientists 2000

Authors and Affiliations

  • Jakob Kristensen
    • 1
  • Torben Schæfer
    • 1
  • Peter Kleinebudde
    • 2
  1. 1.Department of PharmaceuticsThe Royal Danish School of PharmacyCopenhagen EastDenmark
  2. 2.Institute of Pharmaceutics and BiopharmaceuticsMartin Luther UniversityHalle-WittenbergGermany

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