MRI study of fickian, case II and anomalous diffusion of solvents into hydroxypropylmethylcellulose
MRI study of fickian, case II and anomalous diffusion of solvents into hydroxypropylmethylcellulose
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DOI：
10.1007/bf03166337
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发表时间：
2005-01-01
影响因子：
1
通讯作者：
Pislewski, N
中科院分区：
文献类型：
--
作者：
Tritt-Goc, J;Kowalczuk, J;Pislewski, N
采用磁共振成像研究了羟丙基甲基纤维素（HPMC）基质的扩散和溶胀过程。将圆柱体形式的聚合物在pH为2、7和12的水溶剂中在37 ℃下水合，并在Bruker Avance 300 MHz光谱仪上以相等的间隔监测。空间分辨的自旋-自旋弛豫时间和自旋密度连同聚合物的玻璃核的尺寸的变化被确定为作为水合时间的函数的HPMC片剂。根据T-2参数，估算了HPMC凝胶层内的溶剂分子迁移率。所有研究参数均允许确定溶剂扩散至HPMC基质中，碱性溶剂为菲克扩散，酸性溶剂为情况11，中性溶剂为异常扩散。
Magnetic resonance imaging was used to investigate the diffusion and swelling processes of a hydroxypropylmethylcellulose (HPMC) matrix. Polymer in the form of a cylinder was hydrated in a water solvent with pH 2, 7, and 12 at 37 degrees C and monitored at equal intervals on a Bruker Avance 300 MHz spectrometer. The spatially resolved spin-spin relaxation times and spin densities together with the change in the dimension of the glass core of the polymer were determined for the HPMC tablets as a function of hydration times. From T-2 parameters, the solvent molecule mobility within the gel layer of the HPMC was estimated. All studied parameters allow the determination of the diffusion of the solvent into the HPMC matrix as Fickian diffusion for alkaline solvents, case 11 for acidic solvent, and anomalous diffusion for neutral solvent.