Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan.
Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan.
Int J Pharm. 2017 Oct 30;532(1):318-327. doi: 10.1016/j.ijpharm.2017.09.021. Epub 2017 Sep 9.
We aimed to understand the factors controlling mechanical particle coating using polymethacrylate. The relationship between coating performance and the characteristics of polymethacrylate powders was investigated. First, theophylline crystals were treated using a mechanical powder processor to obtain theophylline spheres (<100μm). Second, five polymethacrylate latexes were powdered by spray freeze drying to produce colloidal agglomerates. Finally, mechanical particle coating was performed by mixing theophylline spheres and polymethacrylate agglomerates using the processor. The agglomerates were broken under mechanical stress to coat the spheres effectively. The coating performance of polymethacrylate agglomerates tended to increase as their pulverization progressed. Differences in the grindability of the agglomerates were attributed to differences in particle structure, resulting from consolidation between colloidal particles. High-grindability agglomerates exhibited higher pulverization as their glass transition temperature (T) increased and the further pulverization promoted coating. We therefore conclude that the minimization of polymethacrylate powder by pulverization is an important factor in mechanical particle coating using polymethacrylate with low deformability. Meanwhile, when product temperature during coating approaches T of polymer, polymethacrylate was soften to show high coating performance by plastic deformation. The effective coating by this mechanism may be accomplished by adjusting the temperature in the processor to the T.
我们旨在了解使用聚甲基丙烯酸酯控制机械颗粒包衣的因素。研究了包衣性能与聚甲基丙烯酸酯粉末特性之间的关系。首先，通过机械粉末处理器处理茶碱晶体，获得茶碱球（<100μm）。其次，通过喷雾冷冻干燥将五种聚甲基丙烯酸酯乳液粉末化，以产生胶体团聚体。最后，通过处理器混合茶碱球和聚甲基丙烯酸酯团聚体进行机械颗粒包衣。团聚体在机械应力下破裂，从而有效地包衣球体。随着团聚体的粉碎，其包衣性能趋于增加。团聚体的可粉碎性差异归因于颗粒结构的差异，这是由于胶体颗粒之间的固结造成的。高可粉碎性团聚体的粉碎度随着玻璃化转变温度（T）的升高而升高，进一步的粉碎促进了包衣。因此，我们得出结论，通过粉碎使聚甲基丙烯酸酯粉末最小化是使用低变形性聚甲基丙烯酸酯进行机械颗粒包衣的一个重要因素。同时，当包衣过程中的产品温度接近聚合物的 T 时，聚甲基丙烯酸酯变软，通过塑性变形表现出高包衣性能。通过调整处理器中的温度至 T，可以实现这种机制的有效包衣。
