Medical Nanosystem Engineering Laboratory, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan.
Biomodeling Laboratory, Department of Applied Information Sciences, Graduate School of Information Sciences, Tohoku University, Sendai, Japan.
Adv Exp Med Biol. 2021;1293:481-491. doi: 10.1007/978-981-15-8763-4_32.
We have developed a Si opt-electro multifunctional neural probe with multiple waveguides and embedded optical fiber for highly accurate optical stimulation. The Si opt-electro multifunctional neural probe had 16 recording sites, three optical waveguides, and metal cover for suppressing light leakage. The other opt-electro multifunctional neural probe had an optical fiber in the trench of the probe shank, which leads to fewer damages to tissues. We evaluated the electrochemical properties of the recording sites and confirmed that the neural probe had suitable characteristics for neural recording. We also demonstrated the optical stimulation to the neurons expressing ChR2 using our probe. As a result, we succeeded in multisite optical stimulation and observed that no light leakage from the optical waveguides because of the metal cover. From in vivo experiments, we successfully recorded optically modulated local field potential using the fabricated Si neural probe with optical waveguides. Moreover, we applied current source density analysis to the recorded LFPs. As a result, we confirmed that the light-induced membrane current sinks in the locally stimulated area. The Si opto-electro multifunctional neural probe is one of the most versatile tools for optogenetics.
我们开发了一种具有多个波导和嵌入式光纤的 Si 光电多功能神经探针，可实现高精度的光学刺激。该 Si 光电多功能神经探针具有 16 个记录位点、三个光学波导和金属盖，可抑制漏光。另一种光电多功能神经探针在探针柄的沟槽中有光纤，这导致对组织的损伤更小。我们评估了记录位点的电化学性质，并确认该神经探针具有适合神经记录的特性。我们还使用我们的探针演示了对表达 ChR2 的神经元进行光学刺激。结果，我们成功地进行了多部位光学刺激，并且由于金属盖，没有观察到光学波导中的漏光。通过体内实验，我们成功地使用带有光学波导的 Si 神经探针记录了光调制的局部场电位。此外，我们对记录的 LFPs 进行了电流源密度分析。结果，我们证实了光诱导的膜电流在局部刺激区域内耗散。Si 光电多功能神经探针是光遗传学最通用的工具之一。
