Boateng Joshua S, Matthews Kerr H, Auffret Anthony D, Humphrey Mike J, Stevens Howard N, Eccleston Gillian M
Department of Pharmaceutical Sciences, Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, John Arbuthnott Building, 27 Taylor Street, Glasgow G4 0NR, UK.
Int J Pharm. 2009 Aug 13;378(1-2):66-72. doi: 10.1016/j.ijpharm.2009.05.038. Epub 2009 May 27.
Drug dissolution and release characteristics from freeze-dried wafers and solvent-cast films prepared from sodium carboxymethylcellulose (CMC) have been investigated to determine the mechanisms of drug release from the two systems. The formulations were prepared by freeze-drying (wafers) or drying in air (films), the hydrated gel of the polymer containing paracetamol as a model soluble drug. Scanning electron microscopy (SEM) was used to examine differences between the physical structure of the wafers and films. Dissolution studies were performed using an exchange cell and drug release was measured by UV spectroscopy at 242 nm. The effects of drug loading, polymer content and amount of glycerol (films) on the release characteristics of paracetamol were investigated. The release profiles of paracetamol from the wafers and films were also compared. A digital camera was used to observe the times to complete hydration and dissolution of the wafers containing different amounts of CMC and how that impacts on drug release rates. Both formulations showed sustained type drug release that was modelled by the Korsmeyer-Peppas equation. Changes in the concentration of drug and glycerol (films) did not significantly alter the rate of drug release while increasing polymer content significantly decreased the rate of drug release from both formulations. The results show that the rate of paracetamol release was faster from the wafers than the corresponding films due to differences in their physical structures. The wafers which formed a porous network, hydrated faster than the more dense and continuous, (non-porous) sheet-like structure of the films.
已对由羧甲基纤维素钠（CMC）制备的冻干薄片和溶剂浇铸膜的药物溶解和释放特性进行了研究，以确定药物从这两种体系中释放的机制。通过冷冻干燥（薄片）或在空气中干燥（薄膜）来制备制剂，聚合物的水合凝胶含有对乙酰氨基酚作为模型可溶性药物。使用扫描电子显微镜（SEM）检查薄片和薄膜物理结构之间的差异。使用交换池进行溶解研究，并通过紫外光谱在242nm处测量药物释放。研究了药物负载量、聚合物含量和甘油量（薄膜）对乙酰氨基酚释放特性的影响。还比较了对乙酰氨基酚从薄片和薄膜中的释放曲线。使用数码相机观察含有不同量CMC的薄片完全水合和溶解的时间，以及这如何影响药物释放速率。两种制剂均显示出符合Korsmeyer-Peppas方程模型的持续型药物释放。药物和甘油（薄膜）浓度的变化并未显著改变药物释放速率，而增加聚合物含量则显著降低了两种制剂的药物释放速率。结果表明，由于其物理结构的差异，对乙酰氨基酚从薄片中的释放速率比对相应薄膜更快。形成多孔网络的薄片比薄膜更致密和连续的（无孔）片状结构水合更快。
