Eudragit^® RS PO/RL PO as rate-controlling matrix-formers via roller compaction: Influence of formulation and process variables on functional attributes of granules and tablets

Abstract

The influence of plasticizer level, roll pressure and sintering temperature was investigated on the granule properties, tablet breaking force and theophylline release from tablets. Nine formulations using theophylline as a model drug, Eudragit^® RL PO, Eudragit^® RS PO, or both as a matrix former and triethyl citrate (TEC) as a plasticizer were prepared. The formulations were roller compacted and the granules obtained were evaluated for particle size distribution and flowability. These granules were compacted into tablets at a compression force of 7 kN. The tablets were thermally treated at different temperatures (50 and 75°C) for 5 h and were evaluated for breaking force and dissolution. Increase in roll pressure and TEC levels resulted in a progressive increase in the mean particle size of the granules. The flowability of the granules also improved with increasing roll pressures and TEC levels. Tablet breaking force increased with an increase in TEC levels and sintering temperatures. But these effects were significant only at the highest level of plasticizer and sintering temperature respectively. For the tablets containing Eudragit^® RS PO, theophylline release decreased proportionately with increase in TEC levels and sintering temperatures. Tablets containing either Eudragit^® RL PO or a mixture of RS PO and RL PO failed to impart an extended-release property to the tablets at the studied variables i.e. roll pressure, TEC levels and sintering temperature. It was clearly demonstrated that with suitable optimization of these parameters, the release-rate of a water soluble drug from the matrix tablets prepared via roller compaction can be finely controlled.

Keywords::

• Eudragit^® RL PO
• Eudragit^® RS PO
• roller-compaction
• plasticizer
• sintering

Acknowledgements

The authors are thankful to Alexanderwerk Inc., Horsham, PA, USA for the equipment loan. The authors are also thankful to CIPET (Consortium for Industrial Pharmaceutics Education and Training) and FDA for funding the study.

Declaration of interest

The authors declare that none of the authors have any relationship with any organization or person or financial interest in the subject matter or materials discussed in this manuscript that may affect the conduct or reporting of the work submitted.