Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0448, USA.
Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0448, USA.
Adv Healthc Mater. 2024 Nov;13(29):e2402215. doi: 10.1002/adhm.202402215. Epub 2024 Jul 16.
Durable and conductive interfaces that enable chronic and high-resolution recording of neural activity are essential for understanding and treating neurodegenerative disorders. These chronic implants require long-term stability and small contact areas. Consequently, they are often coated with a blend of conductive polymers and are crosslinked to enhance durability despite the potentially deleterious effect of crosslinking on the mechanical and electrical properties. Here the grafting of the poly(3,4 ethylenedioxythiophene) scaffold, poly(styrenesulfonate)-b-poly(poly(ethylene glycol) methyl ether methacrylate block copolymer brush to gold, in a controlled and tunable manner, by surface-initiated atom-transfer radical polymerization (SI-ATRP) is described. This "block-brush" provides high volumetric capacitance (120 F cm), strong adhesion to the metal (4 h ultrasonication), improved surface hydrophilicity, and stability against 10 000 charge-discharge voltage sweeps on a multiarray neural electrode. In addition, the block-brush film showed 33% improved stability against current pulsing. This approach can open numerous avenues for exploring specialized polymer brushes for bioelectronics research and application.
能够实现神经活动的慢性和高分辨率记录的耐用且导电的接口对于理解和治疗神经退行性疾病至关重要。这些慢性植入物需要长期稳定性和小的接触面积。因此，它们通常涂有导电聚合物的混合物，并进行交联以增强耐用性，尽管交联对机械和电气性能具有潜在的有害影响。在这里，通过表面引发原子转移自由基聚合（SI-ATRP）以可控和可调的方式将聚（3,4-亚乙基二氧噻吩）支架、聚（苯乙烯磺酸盐）-b-聚（聚（乙二醇）甲基醚甲基丙烯酸酯嵌段共聚物刷接枝到金上。这种“嵌段-刷”提供了高体积电容（120 F cm）、与金属的强附着力（4 h 超声处理）、改善的表面亲水性以及在多阵列神经电极上 10000 次充放电电压扫描中的稳定性。此外，嵌段-刷膜在电流脉冲方面显示出 33%的稳定性提高。这种方法可以为生物电子学研究和应用探索专门的聚合物刷开辟众多途径。
