Laboratory of Pharmaceutical Process Analytical Technology, Ghent University, Belgium.
Eur J Pharm Sci. 2011 Dec 18;44(5):635-42. doi: 10.1016/j.ejps.2011.10.011. Epub 2011 Oct 19.
Extrusion-spheronization (ES) is a frequently used agglomeration process in the pharmaceutical industry to manufacture spherical solid units or pellets with a narrow size and shape distribution. In this study, photometric stereo imaging was applied in real-time during the final steps of the ES process, being spheronization and drying. In addition to the pellet size distribution of undispersed (wet) samples, the imaging technique captures visual information on pellet shape and surface brightness. Pellet samples were taken at 20 time points during spheronization and were imaged at-line (during spheronization) and off-line (after spheronization). Particle size distributions and visual image information were both used to characterise the spheronization behaviour of different formulations. Next, particle size distributions and surface brightness values calculated from the at-line obtained images during fluid bed drying of pellets were analysed. The particle size distribution and brightness value changes occurring during pellet drying were explained both by the reduction in residual moisture content and drug solid-state transition. Due to the rapidness of the technique with regard to sample preparation, sample measurement and the acquisition of results in combination with the possibility to measure undispersed (wet) samples, valuable information on spheronization and drying characteristics of different formulations was obtained in real-time.
挤出滚圆（ES）是制药行业中常用的团聚工艺，用于制造具有窄粒径分布和形状的球形固体单元或颗粒。在这项研究中，在 ES 过程的最后步骤（即滚圆和干燥）中实时应用了光度立体成像技术。除了未分散（湿）样品的颗粒尺寸分布外，该成像技术还可以捕获颗粒形状和表面亮度的视觉信息。在滚圆过程中，在 20 个时间点采集颗粒样品，并在线（滚圆过程中）和离线（滚圆后）进行成像。粒径分布和视觉图像信息都用于表征不同配方的滚圆行为。然后，分析了在流化床干燥过程中从在线获得的图像计算得到的颗粒的粒径分布和表面亮度值。颗粒干燥过程中发生的粒径分布和亮度值变化可以通过残余水分含量的减少和药物固-固转变来解释。由于该技术在样品制备、样品测量和结果获取方面具有快速的特点，结合测量未分散（湿）样品的可能性，实时获得了不同配方的滚圆和干燥特性的有价值信息。
