pH responsive hydrogels are ideal platforms for numerous therapeutic delivery applications, including oral delivery, as they are capable of overcoming the many barriers that must be considered when creating an effective drug delivery system. Understanding of the innate hydrogel network structure and its swelling behavior at environmentally relevant conditions is vital for designing hydrogel network capable of effective controlled drug release. Herein, we explored how to expand traditional techniques of swelling and pore characterization to gain better insight into the performance of anionic microparticles composed of the poly(methyl methacrylate‐co‐acrylic acid) with varying molar percentage of 10, 20, and 30 mol% of MMA, for controlled release of low‐molecular‐weight drugs. By evaluating these carrier systems at environmental conditions, we can observe changes in swelling and pore size of the anionic hydrogel networks as a function of MMA, which was then correlated with the release profiles of the small‐molecular‐weight drug sodium nitrate. With the correlation of the swelling behavior of the networks and the release profiles, we demonstrated how the expansion of swelling parameters at relevant pH values provides further incite for evaluating for the optimal blend for controlled release. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48767.

中文翻译：

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pH响应水凝胶对网孔尺寸和溶胀对药物递送的影响

pH响应水凝胶是许多治疗性输送应用（包括口服输送）的理想平台，因为它们能够克服创建有效药物输送系统时必须考虑的许多障碍。了解先天水凝胶网络结构及其在环境相关条件下的溶胀行为对于设计能够有效控制药物释放的水凝胶网络至关重要。在此，我们探讨了如何扩大肿胀和孔特征的传统技术，以获得更好的洞察聚（甲基丙烯酸甲酯组成的阴离子微粒的表现合作（丙烯酸）（丙烯酸）的摩尔百分比在MMA的10、20和30摩尔％之间变化，用于控制低分子量药物的释放。通过在环境条件下评估这些载体系统，我们可以观察到阴离子水凝胶网络的溶胀和孔径变化与MMA的关系，然后与小分子量药物硝酸钠的释放曲线相关。通过网络的溶胀行为与释放曲线的相关性，我们证明了在相关pH值下溶胀参数的扩展如何为评估控释的最佳混合物提供了进一步的诱因。分级为4 +©2019 Wiley Periodicals，Inc.J.Appl。Polym。科学 2020，137，48767。