J Phys Chem B. 2018 Jul 26;122(29):7201-7218. doi: 10.1021/acs.jpcb.8b02919. Epub 2018 Jul 11.
Macroporous hydrogel monoliths having tailor-made features, conductivity, superstretchability, excellent biocompatibility, and biodegradability, have become the most nurtured field of interest in soft biomaterials. Green method assisted reduced graphene oxide has been inserted by in situ free radical gelation into semi-IPN hydrogel matrix to fabricate conducting hydrogel. Mechanical toughness has been implemented for the graphene-polymer physisorption interactions with graphene basal planes. Moreover, the as-prepared 3D scaffold type monolith hydrogel has been rheologically superior regarding their high elastic modulus and delayed gel rupturing. κ-Carragenaan, one of the components of the hydrogel, has biodegradable nature. The most significant outcome is their low electrical percolation threshold and reversibly ductile nature. Reversible ductility provides them with rubber-like consistency in flow conditions. Surprising, the hydrogels showed dual stimuli-responsiveness, that is, environmental pH and external electrical stimulation. Electro-stimulation has been adopted here for the first time in semi-IPN systems, which could be an ideal alternative for iontopheretic devices and pulsatile drug release through skin. Regarding this, the hydrogel also has been passed to biocompatibility assay; they are noncytotoxic and show cell proliferation without negligible cell death in live-dead assay. The porosity of the nanocomposite scaffold-like gels was also analyzed by microcomputed tomography (μ-CT), which exhibited their connectivity in cell/voids inside the matrix. Thus, the experimentations are on the support of biocompatible soft material for dual-responsive tunable drug delivery.
具有定制特性、导电性、超拉伸性、出色的生物相容性和可生物降解性的大孔水凝胶整体材料,已成为软生物材料领域最受关注的热点。绿色辅助方法已将还原氧化石墨烯通过原位自由基凝胶插入半互穿水凝胶基质中,以制备导电水凝胶。通过石墨烯与石墨烯基面的聚合物物理吸附相互作用,实现了机械韧性。此外,所制备的 3D 支架型整体水凝胶在高弹性模量和延迟凝胶破裂方面具有流变学优势。κ-卡拉胶是水凝胶的成分之一,具有可生物降解性。最显著的结果是它们的低电渗流阈值和可逆韧性。可逆韧性使它们在流动条件下具有橡胶状的一致性。令人惊讶的是,水凝胶表现出双重刺激响应性,即环境 pH 值和外部电刺激。在这里,电刺激首次被应用于半互穿系统,这可能是离子电渗设备和通过皮肤脉冲式药物释放的理想替代品。关于这一点,水凝胶也已经通过了生物相容性测试;它们是非细胞毒性的,在活死测试中没有明显的细胞死亡,显示出细胞增殖。纳米复合材料支架状凝胶的孔隙率也通过微计算机断层扫描 (μ-CT) 进行了分析,这显示了它们在基质内部细胞/空隙中的连通性。因此,实验支持用于双重响应可调药物输送的生物相容软材料。