Soh J L P, Liew C V, Heng P W S
Department of Pharmacy, National University of Singapore, 18 Science Drive 4, S117543, Singapore.
Int J Pharm. 2006 Jun 6;315(1-2):99-109. doi: 10.1016/j.ijpharm.2006.02.023. Epub 2006 Mar 6.
This study explored the feasibility of predicting the quality of microcrystalline cellulose (MCC) pellets prepared by extrusion-spheronization using torque rheological characterization. Rheological properties of eleven MCC grades as well as their binary mixtures with lactose (3:7) at various water contents were determined using a mixer torque rheometer (MTR). Derived torque parameters were: maximum torque and cumulative energy of mixing (CEM). CEM values of MCC powders (CEM((MCC))) could be attributed to their physical properties such as crystallinity, V(low P) and V(total) (volumes of mercury intruded in their pores at low pressure and the total intrusion volume), bulk and tapped densities. For both MCC powders and their binary mixtures, strong correlation was observed between their torque parameters and the properties of their pellets formed with 30 and 35% (w/w) water. Since this relationship was valid over a broad water content range, rheological assessment for pre-formulation purposes need not be performed at optimized water contents. These results demonstrated the usefulness of torque rheometry as an effective means of comparing and evaluating MCC grades especially when substitution of equivalent grades is encountered. In so doing, the tedious and expensive pre-production (pre-formulation and optimization) work can be considerably reduced.
本研究探讨了使用扭矩流变学表征来预测通过挤出滚圆法制备的微晶纤维素（MCC）微丸质量的可行性。使用混合器扭矩流变仪（MTR）测定了11种MCC等级及其与乳糖（3:7）在不同含水量下的二元混合物的流变特性。得出的扭矩参数为：最大扭矩和混合累积能量（CEM）。MCC粉末的CEM值（CEM((MCC))）可归因于其物理性质，如结晶度、V(low P)和V(total)（低压下汞侵入其孔隙的体积和总侵入体积）、堆密度和振实密度。对于MCC粉末及其二元混合物，观察到它们的扭矩参数与其在30%和35%（w/w）含水量下形成的微丸性质之间存在强相关性。由于这种关系在较宽的含水量范围内有效，因此无需在优化的含水量下进行用于处方前目的的流变学评估。这些结果证明了扭矩流变学作为比较和评估MCC等级的有效手段的有用性，特别是在遇到等效等级替代时。这样做可以大大减少繁琐且昂贵的生产前（处方前和优化）工作。
