Department of Biomedical Engineering, the University of Texas at Austin, Austin, TX 78712, United States of America.
J Neural Eng. 2019 Jun;16(3):035001. doi: 10.1088/1741-2552/ab05b6. Epub 2019 Feb 8.
Implanted microelectrodes provide a unique means to directly interface with the nervous system but have been limited by the lack of stable functionality. There is growing evidence suggesting that substantially reducing the mechanical rigidity of neural electrodes promotes tissue compatibility and improves their recording stability in both the short- and long-term. However, the miniaturized dimensions and ultraflexibility desired for mitigating tissue responses preclude the probe's self-supported penetration into the brain tissue.
Here we demonstrate the high-throughput implantation of multi-shank ultraflexible neural electrode arrays with surgical footprints as small as 200 µm in a mouse model. This is achieved by using arrays of tungsten microwires as shuttle devices, and bio-dissolvable adhesive polyethylene glycol (PEG) to temporarily attach a shank onto each microwire.
We show the ability to simultaneously deliver electrode arrays in designed patterns, to adjust the implantation locations of the shanks by need, to target different brain structures, and to control the surgical injury by reducing the microwire diameters to cellular scale.
These results provide a facile implantation method to apply ultraflexible neural probes in scalable neural recording.
植入式微电极为直接与神经系统接口提供了一种独特的手段,但由于缺乏稳定性而受到限制。越来越多的证据表明,大大降低神经电极的机械硬度可以促进组织相容性,并提高其在短期和长期内的记录稳定性。然而,为了减轻组织反应而需要的微型化尺寸和超柔韧性排除了探头自行穿透脑组织的可能性。
在这里,我们展示了在小鼠模型中以小至 200µm 的手术足迹进行多叉 ultraflexible 神经电极阵列的高通量植入。这是通过使用钨微丝阵列作为穿梭装置,并使用可生物降解的粘合剂聚乙二醇 (PEG) 将一个叉暂时附着到每个微丝上来实现的。
我们展示了以设计模式同时递送电极阵列的能力,根据需要调整叉的植入位置,以靶向不同的大脑结构,并通过将微丝直径减小到细胞尺度来控制手术损伤。
这些结果提供了一种简便的植入方法,可在可扩展的神经记录中应用 ultraflexible 神经探针。