Utilizing melt crystallization fundamentals in the development of a new tabletting technology

Abstract

Increasing production effeciency and lowering costs are some of the many advantages melt crystallization technology offers over the conventional methodology of tabletting. A normal tablet consists of a pure shell or a coat and a separate core constituting the pharmaceutical active ingredient. Great emphasis is put on the purity of the shell since its purpose is to solely protect and deliver the active ingredient to its target. Melt crystallization is a purification (separation) process. It is discussed here for its ability to produce coated tablets, by separating the “coating” material from the “to be coated” material coming from one molten mixture. Molten drops of lutrol-ibuprofen mixture are produced using the drop forming technique. The subsequent analysis involves proving and quantifying the phase separation (coat purity). The mechanism of a crystallizing drop is shown as direct evidence of the ongoing process. Moreover, solidified tablet batches are analyzed for the purity of their coating by measuring the ibuprofen concentration. This optimization process is carried out through multiple stages of development and condition enhancements in order to produce the most pure tablet coating. As a result, a trial showing an almost purely coated tablet is presented here.

Key words： phase separation; melt crystallization; tablets; process optimization

Acknowledgments

The results are an outcome of the VIP project “In situ Beschichtung” supported by the Federal Ministry of Education and Research of the German Federal Republic. Further researchers in the project are A. Hartwig and K. Wendt.

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