微晶纖維素之物理性修飾

1. 微晶纖維素之物理性修飾 • 在直接壓錠(direct compression)方面上，微晶纖維素(M • icrocrystalline cellulose,MCC) 由於具備良好壓錠性 (Comp • actibility)性質的條件，因此為市面上最受歡迎的直接壓錠 • 賦形劑。微晶纖維素其成錠機轉主要是以塑性形變(plastic d • eformation)為主。同時顆粒的形狀呈不規則狀提供顆粒與顆 • 粒之間以機械連結(mechanical interlocking)的結合方式成 • 錠，然而，不規則的顆粒又會造成粉末的流動性差。 • 有鑑於此，本實驗希望藉由beta-cyclodextrin 與MCC slur • ry共同乾燥製備來修飾其基本物性性質以及了解其壓錠性 • 質。由實驗結果顯示，MCC slurry藉由beta-cyclodextrin共製明 • 顯改善其流動性，其中以顆粒大小為61~149mm(處方2L ~ 4 • L)最明顯。其原因可能是由於共製後的顆粒形狀呈較規則所 • 造成。此外，其錠片的硬度以及崩散性隨著beta-cyclodextrin量 • 比例增加也有明顯較佳的效果。在壓錠性質方面利用Heckel • Plot公式評估發現L及S處方隨著beta-CD的量增加，其Yield Pr • essure都有增加的現象，而且藉由其錠片表面及橫切面之SE • M圖顯示，可推測MCC與beta-CD共製後，其成錠機轉仍以塑性 • 形變方式進行。

2. Physical Modification of Microcrystalline Cellulose • Microcrystalline cellulose (MCC) is a material that i • s very popularly used as an excipient in the production of • tablets as a result that it exhibits the best compactibility i • n the direct compression. MCC powders are known to for • m tablets mainly through plastic deformation. However, the • irregularly shaped particles of MCC, which might improve • the tensile strength of tablets as a result of mechanical int • erlocking bonding, is responsible for its poor flowability of • smaller size grade of MCC. • In an attempt to improve the flowability of MCC w • ithout sacrificing its compactibility, MCC was codried with • various amount of beta-cyclodextrin (beta-CD). The physical ch • aracters of the resulting powder and tablets were examined • and compared. The results showed that the modification o • f MCC by codrying with beta-CD significantly improved the • flowability of original powder of MCC. This could due to • the improved rounded shape of codrying particles. It was f • urther confirmed to be true by SEM. Moreover, the compa • ctibility and disintegration of tablets produced with the cod • rying powders were much better than those using MCC alo • ne and even better than various grades of MCC commercia • lly available. Data from the Heckel plot indicated that the • yield pressure for two different size fractions (61-149 mm • and 37-61 mm) increased with the increase of the added a • mount of beta-CD in the formulations. By SEM examinations • on the surface and cross-section of tablets, all demonstrat • ed that codried prodcuts of MCC tablets still through plasti • c deformation.