Traditional hydrogel usually had restricted application in biomedical field due to lack of control unit. Azobenzene (AZO) was a typical kind of photo-response molecules, but AZO and its small molecular derivatives had serious problems of uncontrollable recovery and light fatigue. While time and space dependence of polymer motion could solve the problem according to previous research. Herein, it was introduced into hydrogel by polymerization to provide a control unit for hydrogel. Firstly, two kinds of crosslinkable AZO molecules with different functionality, namely AZO crosslinker and AZO monomer, were synthesized to be polymerized with traditional hydrophilic monomers. Thus, two kinds of yellow transparent hydrogels, AZO copolymerized hydrogel and AZO crosslinked hydrogel, were obtained. As important properties for traditional hydrogel contact lenses, gelation time and swelling ratio of hydrogels as a function of AZO concentration as well as crosslinking type were investigated. Moreover, synthesized hydrogels exhibited typical porous morphology, but their size and homogeneity were dependent on the type of hydrogel. As a control unit, reversible and controllable photo-responsive performance was desired for photo-response material. Therefore, detailed photo induced isomerization of both AZO copolymerized hydrogel and crosslinked hydrogel were tracked by UV spectra. The results confirmed the reversible, stable and controllable photo responsive process. In vitro evaluation was used to investigate drug release behavior using orfloxacin and puerarin as model drugs. It was found that AZO addition as well as hydrogel type would influence puerarin release, but would have little effect on the orfloxacin release behavior in hydrogels. Furthermore, isomer type in hydrogel would have some effects on drug release behavior including orfloxacin and puerarin.

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用于功能性隐形眼镜的光响应水凝胶的设计与制备

由于缺乏控制单元，传统的水凝胶通常在生物医学领域的应用受到限制。偶氮苯（AZO）是一种典型的光响应分子，但偶氮及其小分子衍生物存在恢复不可控和光疲劳的严重问题。而根据先前的研究，聚合物运动的时间和空间依赖性可以解决这个问题。在本文中，通过聚合将其引入水凝胶中以提供水凝胶的控制单元。首先，合成了两种不同官能度的可交联偶氮分子，即偶氮交联剂和偶氮单体，与传统的亲水单体进行聚合。由此，获得了两种黄色透明水凝胶，偶氮共聚水凝胶和偶氮交联水凝胶。作为传统水凝胶隐形眼镜的重要特性，研究了水凝胶的凝胶时间和溶胀率与 AZO 浓度和交联类型的关系。此外，合成的水凝胶表现出典型的多孔形态，但它们的大小和均匀性取决于水凝胶的类型。作为控制单元，光响应材料需要可逆和可控的光响应性能。因此，通过紫外光谱跟踪了 AZO 共聚水凝胶和交联水凝胶的详细光致异构化。结果证实了可逆、稳定和可控的光响应过程。以奥氟沙星和葛根素为模型药物，通过体外评价研究药物释放行为。结果表明，AZO的添加以及水凝胶的类型会影响葛根素的释放，但对水凝胶中奥氟沙星的释放行为影响不大。此外，水凝胶中的异构体类型会对包括奥氟沙星和葛根素在内的药物释放行为产生一些影响。