McNeill M E, Graham N B
University of Strathclyde, Department of Pure & Applied Chemistry, Glasgow, UK.
J Biomater Sci Polym Ed. 1996;7(11):953-63. doi: 10.1163/156856296x00363.
Spheres of poly(ethylene oxide) xerogel from 4-17 mm diameter were impregnated with the drug, proxyphylline, or the herbicide, 2,4-DNa and then partly coated with a water-impermeable elastomer. When placed in water the active additive was released over periods ranging from hours to weeks at a nearly constant rate. The effect of the hydrogel sphere dimensions and the window size through the elastomer, on water uptake and consequent release of the active agent were examined. These devices superficially possess a configuration similar to some commercial osmotic devices though the active-agent release from the devices of this paper is, in fact, diffusive and not osmotically driven. They appear to provide a very versatile and simple design allowing relatively constant release of the active agent over periods of hours to months merely by changing the device geometry.
直径为4 - 17毫米的聚环氧乙烷干凝胶球体被药物丙羟茶碱或除草剂2,4 -二氯苯氧乙酸钠浸渍，然后部分涂上不透水的弹性体。当置于水中时，活性添加剂在数小时至数周的时间内以几乎恒定的速率释放。研究了水凝胶球体尺寸和穿过弹性体的窗口大小对水吸收以及活性剂随之释放的影响。这些装置表面上具有与一些商业渗透装置相似的结构，不过本文所述装置中活性剂的释放实际上是扩散性的，而非渗透驱动的。它们似乎提供了一种非常通用且简单的设计，仅通过改变装置几何形状就能在数小时至数月的时间内实现活性剂的相对恒定释放。
