Abstract：
For a solid understanding of drug characteristics, in vitro measurement of the intrinsic dissolution rate is important. Hydrodynamics are often emphasized as the decisive parameter influencing the dissolution. In this study, experiments and computational fluid dynamic (CFD) simulations showed that the mixing behavior in the rotating disc apparatus causes an inhomogeneous flow field and a systematic error in the calculation of the intrinsic dissolution rate. This error is affected by both the experimental time and the velocity. Due to the rotational movement around the tablet center, commonly utilized in pharmacopeia methods, a broad variance is present with regard to the impact of fluid velocity on individual particles of the specimen surface. As this is significantly reduced in the case of uniform overflow, the flow channel is recommended for investigating the dissolution behavior. It is shown that rotating disc measurements can be compared with flow channel measurements after adjusting the measured data for the rotating disc based on a proposed, representative Reynolds number and a suggested apparatus-dependent correction factor. Additionally, modeling the apparatus-independent intrinsic dissolution rate for different temperatures in the rotating disc apparatus is possible using the adapted Levich\'s equation.
摘要：
为了深入了解药物特性，内在溶出速率的体外测量是重要的。流体动力学通常被强调为影响溶解的决定性参数。在这项研究中,实验和计算流体动力学（CFD）模拟表明，旋转圆盘设备中的混合行为会导致不均匀的流场和内在溶解速率计算中的系统误差。该误差受实验时间和速度的影响。由于围绕平板电脑中心的旋转运动，常用的药典方法，关于流体速度对试样表面单个颗粒的影响，存在广泛的差异。由于这在均匀溢流的情况下显著减少，建议使用流动通道来研究溶解行为。表明，在根据所提出的方法调整旋转盘的测量数据之后，可以将旋转盘的测量值与流动通道的测量值进行比较，代表性雷诺数和建议的设备相关校正因子。此外,可以使用适应的Levich方程对旋转圆盘设备中不同温度下与设备无关的固有溶解速率进行建模。
