Thiel W J, Nguyen L T
J Pharm Pharmacol. 1984 Mar;36(3):145-52. doi: 10.1111/j.2042-7158.1984.tb06928.x.
Very finely divided particulate salicylic acid (2-5 micrometers) was microencapsulated using conventional fluidized bed coating techniques. The process involved spray coating a preformed ordered mixture, in which the micronized particles are adsorbed on the surface of a coarser carrier material. The mixtures contained 0.1, 1.0 and 5.0% weight of microfine model drug (salicylic acid). Between 75 and 95% of the micronized particles were retained on the carrier surface beneath the film. This process offers a novel method of microencapsulating very fine particulate materials, which may find an application in the production of enteric coated and sustained release microdose products. A recent publication on electrostatic charge interactions in ordered mixtures reported that the addition of a third component can affect the stability of a binary ordered mixture. Addition of 2% talc increased the stability of some mixtures during coating and resulted in the microencapsulation of a significantly greater amount of micronized model drug. A 0.1% salicylic acid binary ordered mixture retained 74% of model drug beneath the film, the 0.1% ternary mixture (2% talc) gave a mean retention of 99%.
使用传统的流化床包衣技术对极细的水杨酸颗粒（2 - 5微米）进行微囊化。该过程包括对预先形成的有序混合物进行喷雾包衣，其中微粉化颗粒吸附在较粗载体材料的表面。混合物中含有0.1%、1.0%和5.0%重量的微粉化模型药物（水杨酸）。75%至95%的微粉化颗粒保留在薄膜下方的载体表面。该过程提供了一种微囊化极细颗粒材料的新方法，这可能在肠溶包衣和缓释微剂量产品的生产中得到应用。最近一篇关于有序混合物中静电荷相互作用的出版物报道，添加第三种成分会影响二元有序混合物的稳定性。添加2%滑石粉可提高某些混合物在包衣过程中的稳定性，并导致微粉化模型药物的微囊化量显著增加。含0.1%水杨酸的二元有序混合物在薄膜下方保留了74%的模型药物，含0.1%的三元混合物（2%滑石粉）的平均保留率为99%。
