Kopp S, Beyer C, Graf E, Kubel F, Doelker E
Laboratoire de Pharmacie galénique, Section de Pharmacie, Université de Genève, Geneva, Switzerland.
J Pharm Pharmacol. 1989 Feb;41(2):79-82. doi: 10.1111/j.2042-7158.1989.tb06397.x.
In order to evaluate the role played by polymorphism in the mechanical strength of solid dosage forms (e.g. compressed tablets) and minimize the influence of other factors (such as compaction force, porosity, particle size, and possibly crystal habit), a melted disc technology was developed. With this technique, tablet-shaped discs of zero porosity were prepared by melting powder and subsequent crystallization in the desired modifications. Taking phenobarbitone as a model drug, different methods were used to get discs of forms I, II and III and the amorphous form. Mechanical properties of the discs were assessed, primarily through their bending strength. The Vickers hardness number was also determined for some specimen discs and monocrystals. Results showed that the amorphous form and form III of phenobarbitone gave the toughest discs and would therefore the most suitable materials to manufacture coherent tablets. Moreover, the various preparation methods used resulted in discs of different internal structures. Both crystal size and crystal habit significantly affected the physical properties of the tested materials.
为了评估多晶型在固体剂型（如压制片）机械强度中所起的作用，并尽量减少其他因素（如压制力、孔隙率、粒径以及可能的晶体习性）的影响，开发了一种熔融圆盘技术。利用该技术，通过将粉末熔融并随后以所需变体结晶来制备零孔隙率的片状圆盘。以苯巴比妥作为模型药物，采用不同方法得到晶型I、II和III以及无定形的圆盘。主要通过圆盘的抗弯强度评估其机械性能。还测定了一些试样圆盘和单晶的维氏硬度值。结果表明，苯巴比妥的无定形和晶型III得到的圆盘最坚韧，因此是制造连贯片剂的最合适材料。此外，所采用的各种制备方法导致圆盘具有不同的内部结构。晶体尺寸和晶体习性均显著影响受试材料的物理性能。
