Sun Changquan Calvin
Pfizer Global Research and Development, 7000 Portage Road, Portage, MI 49001, USA.
Int J Pharm. 2006 Dec 1;326(1-2):94-9. doi: 10.1016/j.ijpharm.2006.07.016. Epub 2006 Jul 15.
True density results for a batch of commercial aspartame are highly variable when helium pycnometry is used. Alternatively, the true density of the problematic aspartame lot was obtained by fitting tablet density versus pressure data. The fitted true density was in excellent agreement with that predicted from single crystal structure. Tablet porosity was calculated from the true density and tablet apparent density. After making the necessary measurements for calculating tablet apparent density, the breaking force of each intact tablet was measured and tensile strength was calculated. With the knowledge of compaction pressure, tablet porosity and tensile strength, powder compaction properties were characterized using tabletability (tensile strength versus pressure), compactibility (tensile strength versus porosity), compressibility (porosity versus pressure) and Heckel analysis. Thus, a wealth of additional information on the compaction properties of the powder was obtained through little added work. A total of approximately 4 g of powder was used in this study. Depending on the size of tablet tooling, tablet thickness and true density, 2-10 g of powder would be sufficient for characterizing most pharmaceutical powders.
当使用氦比重瓶法时，一批市售阿斯巴甜的真密度结果变化很大。另外，通过拟合片剂密度与压力数据获得了有问题的阿斯巴甜批次的真密度。拟合得到的真密度与单晶结构预测的结果高度吻合。片剂孔隙率由真密度和片剂表观密度计算得出。在对计算片剂表观密度进行必要测量后，测量了每片完整片剂的断裂力并计算了抗张强度。在知道压实压力、片剂孔隙率和抗张强度的情况下，使用可压性（抗张强度与压力）、成型性（抗张强度与孔隙率）、压缩性（孔隙率与压力）和赫克尔分析来表征粉末的压实特性。因此，通过少量额外工作就获得了大量关于粉末压实特性的附加信息。本研究总共使用了约4克粉末。根据片剂模具的尺寸、片剂厚度和真密度，2 - 10克粉末足以表征大多数药用粉末。
