Fujiwara Maya, Dohi Masafumi, Otsuka Tomoko, Yamashita Kazunari, Sako Kazuhiro
Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Nada, Kobe, Japan.
Chem Pharm Bull (Tokyo). 2013;61(3):320-5. doi: 10.1248/cpb.c12-00969.
Here, we statistically identified the critical factor of the granulation rate during the fluidized bed granulation process. Lactose was selected as the excipient and was granulated with several binders, including hydroxypropyl cellulose, hydroxypropyl methyl cellulose, and polyvinylpyrrolidone. The viscosity, density, and surface tension of the binder solution, contact angle, and the work done during adhesion and cohesion between the binder and lactose, mist diameter, Stokes number, and the dimension of the droplet were considered. The Stokes number was defined as the ratio of the inertial force to the viscous-damping force of a particle. We confirmed that droplet diameter after adhesion had the highest correlation coefficient with the granulation rate constant in our investigated parameters. Partial least squares regression revealed two critical principal components of the granulation rate: one relating to the droplet dimension, which is composed of mist diameter and diameter and thickness of the droplet after adhesion of the binder to the lactose surface; and the other relating to wettability, which involves the work done during adhesion and cohesion, surface tension, and the thickness of the droplet after adhesion of the binder to the lactose surface.
在此，我们通过统计学方法确定了流化床制粒过程中造粒速率的关键因素。选择乳糖作为辅料，并与几种粘合剂一起制粒，这些粘合剂包括羟丙基纤维素、羟丙基甲基纤维素和聚乙烯吡咯烷酮。考虑了粘合剂溶液的粘度、密度和表面张力、接触角以及粘合剂与乳糖之间粘附和内聚过程中所做的功、雾滴直径、斯托克斯数和液滴尺寸。斯托克斯数定义为颗粒惯性力与粘性阻尼力之比。我们证实，在所研究的参数中，粘附后的液滴直径与造粒速率常数的相关系数最高。偏最小二乘回归揭示了造粒速率的两个关键主成分：一个与液滴尺寸有关，由雾滴直径以及粘合剂粘附到乳糖表面后液滴的直径和厚度组成；另一个与润湿性有关，涉及粘附和内聚过程中所做的功、表面张力以及粘合剂粘附到乳糖表面后液滴的厚度。
