Mechanisms of the spheronization process for the formulation of spherical granules

球形颗粒（丸剂）在许多药物应用中非常有用，因为它们具有关于药物释放的特殊性质。基于明确的颗粒表面积，微丸是使用胃耐受或缓释膜的功能性包衣的最佳来源。此外，丸剂显示出均匀的药物释放，这通常会减少副作用。该项目的重点是研究最常见的制造技术-滚圆中的颗粒形成机制。因此，将进行几项滚圆实验，以研究工艺参数和配方变量对工艺动力学的影响。此外，球化过程将分为子过程（聚结，固结和断裂），必须通过离散元方法，接触和断裂力学在不同的长度尺度上进行研究。由于子过程的模拟耦合，其在不同的时间和长度尺度上发生，因此可以计算整个球化过程。通过这种方式，应该可以在造粒过程中获得更深入的见解，从而获得更多的过程理解。基于此，制粒工艺可适用于目前无法用于滚圆的其他药物。

Spherical granules (pellets) are quit useful in many pharmaceutical applications because they have special properties with respect to the drug release. Based on the well-defined particle surface area pellets are the optimal source for a functional coating using gastric-resisted or sustained release films. Moreover, pellets show an uniform drug release, which frequently reduces side effects. This project focuses on the study of the mechanisms of pellet formation in the most common manufacturing technique - spheronisation. Therefore, several spheronisation experiments will be performed in order to investigate influence of process parameters and formulation variables on the process dynamics. Furthermore the spheronisation process will split up in sub-processes (coalescence, consolidation and fracture) that must be investigated on the different length scales by Discrete Element Method, contact and fracture mechanics. Due to the coupling of the simulations for the sub-processes, which take palce on the different time and length scales, it will be possible to calculate the entire spheronisation process. In this way it should be possible to get deeper insights in the pelletization process leading to more process understanding. Based on this, the pelletization process could be applicable to other drug subtracted that cannot be used in spheronisation today.