Granule formation and structure from single drop impact on heterogeneous powder beds
Granule formation and structure from single drop impact on heterogeneous powder beds
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单滴撞击异质粉末床的颗粒形成和结构
DOI：
10.1016/j.ijpharm.2018.09.036
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发表时间：
2018
影响因子：
5.8
通讯作者：
H. Emady
中科院分区：
文献类型：
--
作者：
TianXiang Gao;A. S. Singaravelu;S. Oka;R. Ramachandran;F. Štěpánek;N. Chawla;H. Emady
研究了液滴在静止粉末床中的单滴撞击，考察了颗粒的形成机理、液滴穿透时间以及颗粒的表征（形貌、表面结构和内部结构）。将水用作液体，并将两种药物粉末，微晶纤维素（MCC）和对乙酰氨基酚（APAP）混合以制备非均质粉末床。用高速摄影机记录完整的跌落冲击和穿透。两个颗粒形成机制，已确定以前发生的：蔓延和隧道。APAP含量小于20%的混合物发生铺展，而当APAP含量增加到20%以上时，开始发生Tunneling。随着APAP浓度的增加，平均粒径减小，液滴穿透时间增加，形成的颗粒尺寸变小，这与以前的文献很好地一致。颗粒的形态，表面结构，和内部结构，其特征在于通过棱镜的方法与图像分析，扫描电子显微镜（SEM），和X射线显微断层扫描，分别。Spreading机制产生具有多孔内部结构的扁平圆盘，而Tunnel机制产生具有致密内部结构的圆形颗粒。在从铺展到隧道化的过渡过程中，由非均质混合物制成的颗粒有明显的孔隙率降低和圆度增加的趋势。据信，粉末床的平均粒径和粉末-液体接触角是影响形成机理、液滴穿透时间和颗粒性质的主要因素。
Single drop impact of liquid on a static powder bed was studied to investigate the granule formation mechanism, droplet penetration time, as well as the characterization of granules (morphology, surface structure and internal structure). Water was used as the liquid and two pharmaceutical powders, microcrystalline cellulose (MCC) and acetaminophen (APAP), were mixed to make heterogeneous powder beds. The complete drop impact and penetration was recorded by a high speed camera. Two granule formation mechanisms that have been identified previously occurred: Spreading and Tunneling. Spreading occurred for mixtures with an APAP amount of less than 20%, while Tunneling started to occur when the APAP amount increased above 20%. With an increase of APAP concentration, the mean particle size decreased, drop penetration time increased, and the granules formed became smaller in size, which was in good agreement with previous literature. The granule morphology, surface structure, and internal structure were characterized by a prism method with image analysis, scanning electron microscopy (SEM), and X-ray microtomography, respectively. The Spreading mechanism produced flat disks with a porous internal structure, while the Tunneling mechanism produced round granules with a dense internal structure. There is a clear trend of decreasing porosity and increasing roundness of granules made from heterogeneous mixtures within the transition from Spreading to Tunneling. It is believed that the mean particle size of the powder bed and the powder-liquid contact angle are the predominant factors in influencing the formation mechanism, drop penetration time, and granule properties.
X 射线断层扫描对喷雾流化床软材料团聚体的形貌和内部结构进行三维表征
影响因子：
5.2
作者：
Pashminehazar R;Kharaghani A;Tsotsas E.
通讯作者：
Tsotsas E.