Laboratory of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
Drug Dev Ind Pharm. 2009 Jun;35(6):655-62. doi: 10.1080/03639040802578103.
Multiparticulate drug delivery systems, such as pellets, are frequently used as they offer therapeutic advantages over single-unit dosage forms.
Development of porous pellets followed by evaluation of potential drug loading techniques.
Porous microcrystalline pellets were manufactured and evaluated as drug delivery system. Pellets consisting of Avicel PH 101 and NaCl (70%, w/w) were prepared by extrusion/spheronization. The NaCl fraction was extracted with water and after drying porous pellets were obtained (33.2% porosity). Immersion of the porous pellets in a 15% and 30% (w/v) metoprolol tartrate solution, ibuprofen impregnation via supercritical fluids and paracetamol layering via fluidized bed coating were evaluated as drug loading techniques.
Raman spectroscopy revealed that immersion of the pellets in a drug solution and supercritical fluid impregnation allowed the drug to penetrate into the porous structure of the pellets. The amount of drug incorporated depended on the solubility of the drug in the solvent (water or supercritical CO(2)). Drug release from the porous pellets was immediate and primarily controlled by pure diffusion.
The technique described in this research work is suitable for the production of porous pellets. Drug loading via immersion the pellets in a drug solution and supercritical fluid impregnation resulted in a drug deposition in the entire pellet in contrast to fluid bed layering where drugs were only deposed on the pellet surface.
多颗粒药物传递系统（如微丸）常被用作治疗方法，优于单剂量剂型。
开发多孔微丸，然后评估潜在的药物负载技术。
采用挤出/滚圆法制备多孔微晶微丸，并将其作为药物传递系统进行评价。以 Avicel PH 101 和 NaCl（70%，w/w）为原料制备微丸，其中 NaCl 部分用去离子水提取，干燥后得到多孔微丸（孔隙率为 33.2%）。将多孔微丸分别浸入 15%和 30%（w/v）酒石酸美托洛尔溶液中，用超临界流体对其进行布洛芬浸渍，以及用流化床包衣法对其进行对乙酰氨基酚包衣，评估这些方法作为载药技术的潜力。
拉曼光谱研究表明，微丸浸入药物溶液和超临界流体浸渍可以使药物渗透到微丸的多孔结构中。药物的负载量取决于药物在溶剂（水或超临界 CO2）中的溶解度。多孔微丸的药物释放是立即的，主要由纯扩散控制。
本文研究工作中描述的技术适用于多孔微丸的生产。与流化床包衣技术相比，药物通过浸入溶液和超临界流体浸渍负载到微丸中，药物会沉积在整个微丸中，而流化床包衣技术仅将药物沉积在微丸表面。
