Taylor M Joan, Tanna Sangeeta, Sahota Tarsem S, Voermans Barbara
The Leicester School of Pharmacy, Faculty of Health and Life Sciences, De Montfort University, Leicester, UK.
Eur J Pharm Biopharm. 2006 Jan;62(1):94-100. doi: 10.1016/j.ejpb.2005.07.005. Epub 2005 Sep 22.
The rheological characterisation of glucose sensitive mixtures containing dextran and concanavalin A (con A) with and without glucose, was undertaken using oscillatory rheometry at 20 and 37 degrees C so that comparative data could be gathered in the linear viscoelastic (LVE) range. Measurements for a series of mixtures showed that complex viscosity is a function not only of the con A concentration but of the content and molecular weight of the dextran used. The extent of liquefaction on addition of glucose also depended on these factors. The tan delta profiles confirmed the change from semi-solid towards fluid behaviour. This occurs when glucose effects dismantling of the three-dimensional structure of the dextran-con A system by competitive binding to the glucose receptors in the protein. For the mixtures studied, the changes occurred between contents of 0 and 1% (w/w) glucose at 20 and 37 degrees C and form a useful basis for the formulation of a self-regulating delivery device for the control of hyper-and hypoglycaemia in diabetes.
采用振荡流变仪在20℃和37℃下对含有右旋糖酐和伴刀豆球蛋白A（Con A）且添加或未添加葡萄糖的葡萄糖敏感混合物进行流变学表征，以便在线性粘弹性（LVE）范围内收集对比数据。一系列混合物的测量结果表明，复数粘度不仅是Con A浓度的函数，也是所用右旋糖酐的含量和分子量的函数。添加葡萄糖时的液化程度也取决于这些因素。损耗角正切曲线证实了从半固体向流体行为的转变。当葡萄糖通过与蛋白质中的葡萄糖受体竞争性结合而导致右旋糖酐-Con A系统的三维结构解体时，就会发生这种转变。对于所研究的混合物，在20℃和37℃下，葡萄糖含量在0至1%（w/w）之间时会发生变化，这为开发用于控制糖尿病患者高血糖和低血糖的自调节给药装置提供了有用的依据。
