De Montfort University, The Gateway, Leicester, UK.
Drug Dev Ind Pharm. 2011 Mar;37(3):351-8. doi: 10.3109/03639045.2010.513983.
Dextran methacrylate (dex-MA) and concanavalin A (con A)-methacrylamide were photopolymerized to produce covalently cross-linked glucose-sensitive gels for the basis of an implantable closed-loop insulin delivery device.
The viscoelastic properties of these polymerized gels were tested rheologically in the non-destructive oscillatory mode within the linear viscoelastic range at glucose concentrations between 0 and 5% (w/w).
For each cross-linked gel, as the glucose concentration was raised, a decrease in storage modulus, loss modulus and complex viscosity (compared at 1 Hz) was observed, indicating that these materials were glucose responsive. The higher molecular weight acrylic-derivatized dextrans [degree of substitution (DS) 3 and 8%] produced higher complex viscosities across the glucose concentration range.
These studies coupled with in vitro diffusion experiments show that dex-MA of 70 kDa and DS (3%) was the optimum mass average molar mass to produce gels that show reduced component leach, glucose responsiveness, and insulin transport useful as part of a self-regulating insulin delivery device.
将葡聚糖甲基丙烯酸酯（dex-MA）和刀豆球蛋白 A（con A）-甲基丙烯酰胺光聚合，以生产共价交联的葡萄糖敏感凝胶，作为可植入闭环胰岛素输送装置的基础。
在葡萄糖浓度为 0 至 5%（w/w）的范围内，在无损振荡模式下，通过线性粘弹性范围内的流变学测试这些聚合凝胶的粘弹性特性。
对于每种交联凝胶，随着葡萄糖浓度的升高，观察到储能模量、损耗模量和复数粘度（在 1 Hz 下比较）降低，表明这些材料对葡萄糖有响应。高分子量的丙烯酰化葡聚糖[取代度（DS）为 3 和 8%]在整个葡萄糖浓度范围内产生更高的复数粘度。
这些研究结合体外扩散实验表明，70 kDa 的 dex-MA 和 DS（3%）是产生具有减少成分浸出、葡萄糖响应性和胰岛素传递功能的凝胶的最佳质量平均摩尔质量，可作为自调节胰岛素输送装置的一部分。
