Wu Jiang, He Chaochao, He Huacheng, Cheng Chaoqun, Zhu Junyi, Xiao Zecong, Zhang Hongyu, Li Xiaokun, Zheng Jie, Xiao Jian
School of Pharmaceutical Sciences, Key Laboratory of Biotechnology and Pharmaceutical Engineering, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
J Mater Chem B. 2017 Jun 28;5(24):4595-4606. doi: 10.1039/c7tb00757d. Epub 2017 May 10.
Conventional 2-hydroxyethyl methacrylate (HEMA)-based hydrogels have an inverse relationship between optical transparency (OP) and oxygen permeability (D) as a function of water content. While the higher water content favors the oxygen permeability of HEMA-based hydrogels, it also causes poor optical transparency due to the water-induced scattering center effect. Here, we propose and demonstrate that the incorporation of zwitterionic [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide (SBMA) with HEMA hydrogels enables the achievement of both properties (OP = 98% and D = 54.7) in hydrogels at high water contents of 84%, and both values are much higher than those of pure HEMA hydrogels (OP = 2.3% and D = 17.5 barriers). HEMA-SBMA hydrogels are crosslinked by electrostatic interactions between the zwitterionic SBMA groups and hydrogen bonds between the HEMA groups. The introduction of SBMA into HEMA not only increases the quantity and quality of strongly binding water inside the networks, but also affects the porous structure of the gels, both of which are correlated with OP and D. Moreover, hybrid HEMA-SBMA hydrogels demonstrate their excellent antifouling function to prevent nonspecific protein adsorption in vitro, as well as their biocompatibility and hemocompatibility when implanted in mice in vivo. A combination of these excellent properties of HEMA-SBMA hydrogels (high water content, high optical transparency, high oxygen permeability, good antifouling function, and low foreign-body reaction) makes them highly promising for contact lens-based ophthalmic applications. This work, in line with our other HEMA-CBMA hydrogels, offers a new strategy to design hybrid hydrophilic-zwitterionic materials for improving their multi-faceted properties of interest, beyond the conventional designs of hydrophilic-hydrophilic and hydrophilic-hydrophobic materials.
传统的基于甲基丙烯酸2-羟乙酯（HEMA）的水凝胶，其光学透明度（OP）和透氧性（D）之间存在一种与含水量相关的反比关系。虽然较高的含水量有利于基于HEMA的水凝胶的透氧性，但由于水诱导的散射中心效应，它也会导致较差的光学透明度。在此，我们提出并证明，将两性离子型[2-(甲基丙烯酰氧基)乙基]二甲基-(3-磺丙基)氢氧化铵（SBMA）与HEMA水凝胶相结合，能够在水含量高达84%的水凝胶中同时实现这两种性能（OP = 98%，D = 54.7），且这两个值均远高于纯HEMA水凝胶的值（OP = 2.3%，D = 17.5 barrers）。HEMA-SBMA水凝胶通过两性离子型SBMA基团之间的静电相互作用以及HEMA基团之间的氢键交联。将SBMA引入HEMA中，不仅增加了网络内部强结合水的数量和质量，还影响了凝胶的多孔结构，这两者都与OP和D相关。此外，混合的HEMA-SBMA水凝胶在体外表现出优异的防污功能，可防止非特异性蛋白质吸附，在体内植入小鼠时也表现出生物相容性和血液相容性。HEMA-SBMA水凝胶的这些优异性能（高含水量、高光学透明度、高透氧性、良好的防污功能和低异物反应）相结合，使其在基于隐形眼镜的眼科应用中极具前景。这项工作与我们其他的HEMA-CBMA水凝胶一致，提供了一种新策略来设计混合亲水-两性离子材料，以改善其多方面的感兴趣性能，超越了传统的亲水-亲水和亲水-疏水材料设计。
