Huntington Medical Research Institutes, Pasadena, CA 91105, USA.
IEEE Trans Biomed Eng. 2012 Feb;59(2):346-54. doi: 10.1109/TBME.2011.2172440. Epub 2011 Oct 18.
We developed and validated silicon-based neural probes for neural stimulating and recording in long-term implantation in the brain. The probes combine the deep reactive ion etching process and mechanical shaping of their tip region, yielding a mechanically sturdy shank with a sharpened tip to reduce insertion force into the brain and spinal cord, particularly, with multiple shanks in the same array. The arrays' insertion forces have been quantified in vitro. Five consecutive chronically-implanted devices were fully functional from 3 to 18 months. The microelectrode sites were electroplated with iridium oxide, and the charge injection capacity measurements were performed both in vitro and after implantation in the adult feline brain. The functionality of the chronic array was validated by stimulating in the cochlear nucleus and recording the evoked neuronal activity in the central nucleus of the inferior colliculus. The arrays' recording quality has also been quantified in vivo with neuronal spike activity recorded up to 566 days after implantation. Histopathology evaluation of neurons and astrocytes using immunohistochemical stains indicated minimal alterations of tissue architecture after chronic implantation.
我们开发并验证了基于硅的神经探针，用于大脑中长期植入的神经刺激和记录。这些探针结合了深反应离子刻蚀工艺和尖端区域的机械成型，产生了机械坚固的柄部和锋利的尖端，以减少插入大脑和脊髓的力，特别是在同一阵列中有多个探针时。已经在体外量化了阵列的插入力。连续 5 个植入的设备在 3 到 18 个月内完全正常工作。微电极位点用电镀氧化铱处理，并且在体外和在成年猫脑内植入后进行了电荷注入容量测量。通过在耳蜗核中刺激和记录下丘中央核中的诱发神经元活动，验证了慢性阵列的功能。还通过记录植入后长达 566 天的神经元尖峰活动，在体内量化了阵列的记录质量。使用免疫组织化学染色对神经元和星形胶质细胞进行组织病理学评估表明，慢性植入后组织结构几乎没有改变。
