Badiger M V, McNeill M E, Graham N B
Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK.
Biomaterials. 1993 Nov;14(14):1059-63. doi: 10.1016/0142-9612(93)90206-h.
To enable the synthesis of hydrogels containing microporosity, a family of pore generating additives (porogens) were synthesized from poly(ethylene glycols) (PEGs) with different molecular weights using naphthyl acetic acid. The products formed were characterized by UV-vis, differential scanning calorimetry and solution nuclear magnetic resonance techniques. Subsequently, poly(ethylene oxide)-urethane hydrogels were synthesized incorporating the above mentioned PEG porogens to modify the structure of the hydrogel. These highly water soluble PEG porogens were inert and extracted out in water. The hydrogels obtained exhibited significant increase in the equilibrium water uptake. This was attributed to the formation of a microporous structure in the hydrogel. It was also evidenced by the observed increase in the diffusion coefficients of the drugs proxyphylline and vitamin B12 through this hydrogel. The proportional increase was greater for the higher molecular weight vitamin B12 than for the proxyphylline. These results may be useful in developing porous hydrogels for controlled release technology.
为了实现含微孔水凝胶的合成，使用萘乙酸从不同分子量的聚乙二醇（PEG）合成了一系列造孔添加剂（致孔剂）。通过紫外可见光谱、差示扫描量热法和溶液核磁共振技术对形成的产物进行了表征。随后，合成了聚环氧乙烷 - 聚氨酯水凝胶，其中掺入上述PEG致孔剂以改变水凝胶的结构。这些高度水溶性的PEG致孔剂是惰性的，可在水中萃取出来。所得水凝胶的平衡吸水量显著增加。这归因于水凝胶中形成了微孔结构。通过药物丙羟茶碱和维生素B12通过该水凝胶的扩散系数增加也证明了这一点。分子量较高的维生素B12的比例增加比丙羟茶碱更大。这些结果可能有助于开发用于控释技术的多孔水凝胶。
