Abstract：
Implantable electrodes have raised great interest over the last years with the increasing incidence of neurodegenerative disorders. For brain implant devices, some key factors resulting in the formation of glial scars, such as mechanical mismatch and acute injury-induced inflammation, should be considered for material design. Therefore, in this study, a new biocompatible flexible electrode (e-SgG) with arbitrary shapes on a positive electrode was developed via electrogelation by applying a direct electrical voltage on a silk fibroin/gelatin/reduced graphene oxide composite hydrogel. The implantable flexible e-SgG-2 film with 1.23% rGO content showed high Young\'s modulus (11-150 MPa), which was sufficient for penetration under dried conditions but subsequently became a biomimetic brain tissue with low Young\'s modulus (50-3200 kPa) after insertion in the brain. At the same time, an anti-inflammatory drug (DEX) incorporated into the e-SgG-2 film can be electrically stimulated to exhibit two-stage release to overcome tissue inflammation during cyclic voltammetry via degradation by applying an AC field. The results of cell response to the SF/gelatin/rGO/DEX composite film showed that the released DEX could interrupt astrocyte growth to reduce the inflammatory response but showed non-toxicity toward neurons, which demonstrated a great potential for the application of the biocompatible and degradable e-SgG-D electrodes in the improvement of nerve tissue repair.
摘要：
近年来，随着神经退行性疾病发病率的增加，可植入电极引起了极大的兴趣。对于大脑植入装置，一些导致胶质疤痕形成的关键因素，如机械不匹配和急性损伤引起的炎症，应该考虑材料设计。因此,在这项研究中，通过在丝素蛋白/明胶/还原氧化石墨烯复合水凝胶上施加直流电压,通过电凝胶作用开发了在正电极上具有任意形状的新型生物相容性柔性电极(e-SgG)。rGO含量为1.23%的可植入柔性e-SgG-2膜显示出高杨氏模量(11-150MPa),在干燥条件下足以穿透，但随后在插入脑后成为具有低杨氏模量（50-3200kPa）的仿生脑组织。同时,例如,掺入到e-SgG-2膜中的抗炎药(DEX)可以被电刺激以表现出两阶段释放,从而通过施加AC场通过降解克服循环伏安法期间的组织炎症。细胞对SF/明胶/rGO/DEX复合膜的反应结果表明，释放的DEX可以中断星形胶质细胞的生长，减轻炎症反应，但对神经元无毒性，这证明了生物相容性和可降解的e-SgG-D电极在改善神经组织修复方面的巨大潜力。
