The importance of the microstzructure of silicone hydrogels is widely appreciated but is poorly understood and minimally investigated. To ensure comfort and eye health, these materials must simultaneously exhibit both high oxygen and high water permeability. In contrast with most conventional hydrogels, the water content and water structuring within silicone hydrogels cannot be solely used to predict permeability. The materials achieve these opposing requirements based on a composite of nanoscale domains of oxygen‐permeable (silicone) and water‐permeable hydrophilic components. This study correlated characteristic ion permeation coefficients of a selection of commercially available silicone hydrogel contact lenses with their morphological structure and chemical composition. Differential scanning calorimetry measured the water structuring properties through subdivision of the freezing water component into polymer‐associated water (loosely bound to the polymer matrix) and ice‐like water (unimpeded with a melting point close to that of pure water). Small‐angle x‐ray scattering, and environmental scanning electron microscopy techniques were used to investigate the structural morphology of the materials over a range of length scales. Significant, and previously unrecognized, differences in morphology between individual materials at nanometer length scales were determined; this will aid the design and performance of the next generation of ocular biomaterials, capable of maintaining ocular homeostasis.

中文翻译：

---

结构和形态对商业硅水凝胶隐形眼镜中离子渗透的影响。

有机硅水凝胶微结构的重要性得到广泛认可，但了解甚少，研究也很少。为确保舒适度和眼睛健康，这些材料必须同时具有高透氧性和高透水性。与大多数传统水凝胶相比，硅水凝胶中的水含量和水结构不能单独用于预测渗透性。这些材料基于透氧（硅胶）和透水亲水成分的纳米级复合材料实现了这些相反的要求。该研究将精选的市售硅酮水凝胶隐形眼镜的特征离子渗透系数与其形态结构和化学成分相关联。差示扫描量热法通过将冷冻水组分细分为聚合物缔合水（松散地结合在聚合物基质上）和冰状水（不受阻碍，熔点接近纯水）来测量水的结构特性。小角度 X 射线散射和环境扫描电子显微镜技术被用于研究材料在一系列长度尺度上的结构形态。确定了纳米长度尺度上单个材料之间形态的显着且以前未被认识到的差异；这将有助于下一代眼部生物材料的设计和性能，能够维持眼部稳态。