Sriamornsak Pornsak, Nunthanid Jurairat, Luangtana-anan Manee, Weerapol Yossanun, Puttipipatkhachorn Satit
Department of Pharmaceutical Technology, Faculty of Pharmacy, Silpakorn University, Nakhon Pathom, Thailand.
Eur J Pharm Biopharm. 2008 May;69(1):274-84. doi: 10.1016/j.ejpb.2007.09.012. Epub 2007 Sep 29.
Pellets containing microcrystalline cellulose (MCC), a model drug (theophylline) and a range of levels of sodium alginate (i.e., 10-50% w/w) were prepared by extrusion/spheronization. Two types of sodium alginate were evaluated with and without the addition of either calcium acetate or calcium carbonate (0, 0.3, 3 and 10% w/w). The effects of amount and type of sodium alginate and calcium salts on pellet properties, e.g., size, shape, morphology and drug release behavior, were investigated. Most pellet formulations resulted in pellets of a sufficient quality with respect to size, size distribution and shape. The results showed that the amounts of sodium alginate and calcium salts influenced the size and shape of the obtained pellets. However, different types of sodium alginate and calcium salt responded to modifications to a different extent. A cavity was observed in the pellet structure, as seen in the scanning electron micrographs, resulting from the forces involved in the spheronization process. Most of pellet formulations released about 75-85% drug within 60 min. Incorporation of calcium salts in the pellet formulations altered the drug release, depending on the solubility of the calcium salts used. The drug release data showed a good fit into both Higuchi and Korsmeyer-Peppas equations.
通过挤出滚圆法制备了含有微晶纤维素（MCC）、一种模型药物（茶碱）以及一系列不同水平海藻酸钠（即10 - 50% w/w）的微丸。评估了两种类型的海藻酸钠，分别添加和不添加醋酸钙或碳酸钙（0、0.3、3和10% w/w）。研究了海藻酸钠和钙盐的用量及类型对微丸性质（如尺寸、形状、形态和药物释放行为）的影响。大多数微丸制剂在尺寸、尺寸分布和形状方面都具有足够的质量。结果表明，海藻酸钠和钙盐的用量会影响所获得微丸的尺寸和形状。然而，不同类型的海藻酸钠和钙盐对这些改变的响应程度不同。如扫描电子显微镜照片所示，在微丸结构中观察到一个空洞，这是由滚圆过程中涉及的力导致的。大多数微丸制剂在60分钟内释放约75 - 85%的药物。在微丸制剂中加入钙盐会改变药物释放，这取决于所使用钙盐的溶解度。药物释放数据与Higuchi方程和Korsmeyer - Peppas方程都拟合良好。
