The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
T. Kawano - One of the best experts on this subject based on the ideXlab platform.
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Layer-by-layer assembled nanorough iridium-oxide/Platinum-Black for low-voltage microscale electrode neurostimulation
Sensors and Actuators B: Chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
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layer by layer assembled nanorough iridium oxide Platinum Black for low voltage microscale electrode neurostimulation
Sensors and Actuators B-chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
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layer by layer nanoassembly of iridium oxide Platinum Black for low impedance high charge injecting microelectrode applications
International Conference on Micro Electro Mechanical Systems, 2012Co-Authors: S. Yamagiwa, A. Fujishiro, A. Ikedo, M. Ishida, T. KawanoAbstract:We report an electrode device with a low impedance and high charge injecting characteristics for a powerful application to micro/nano-scale electrophysiological measurements of neuron/cells. Due to the small effective electrode area, conventional microelectrodes exhibit high interfacial electrode impedance (∼10 MΩ at 1 kHz) and low charge injection characteristics, making the targeted cells impossible to record/stimulate. To overcome these limitations, we propose enhanced surface-area of an electrode with a low impedance material, based on layer-by-layer assembled iridium oxide (IrOx)/Platinum-Black (Pt-Black) with nano-scale roughness. The assembled nanorough-IrOx/Pt-Black electrode exhibits 2 times lower impedance and 2.4 times larger injection delivery capacity (Q CDC ) compared to a planer-IrOx electrode with the same size. Additionally, we fabricated nanorough-Ir/Pt-Black tipped microprobes and demonstrated in saline, while improved stimulating currents were observed.
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Layer-by-layer nanoassembly of iridium oxide/Platinum-Black for low impedance, high charge injecting microelectrode applications
2012 IEEE 25th International Conference on Micro Electro Mechanical Systems (MEMS), 2012Co-Authors: S. Yamagiwa, A. Fujishiro, A. Ikedo, M. Ishida, T. KawanoAbstract:We report an electrode device with a low impedance and high charge injecting characteristics for a powerful application to micro/nano-scale electrophysiological measurements of neuron/cells. Due to the small effective electrode area, conventional microelectrodes exhibit high interfacial electrode impedance (~10 MΩ at 1 kHz) and low charge injection characteristics, making the targeted cells impossible to record/stimulate. To overcome these limitations, we propose enhanced surface-area of an electrode with a low impedance material, based on layer-by-layer assembled iridium oxide (IrOx)/Platinum-Black (Pt-Black) with nano-scale roughness. The assembled nanorough-IrOx/Pt-Black electrode exhibits 2 times lower impedance and 2.4 times larger injection delivery capacity (QCDC) compared to a planer-IrOx electrode with the same size. Additionally, we fabricated nanorough-Ir/Pt-Black tipped microprobes and demonstrated in saline, while improved stimulating currents were observed.
S. Yamagiwa - One of the best experts on this subject based on the ideXlab platform.
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Layer-by-layer assembled nanorough iridium-oxide/Platinum-Black for low-voltage microscale electrode neurostimulation
Sensors and Actuators B: Chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
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layer by layer assembled nanorough iridium oxide Platinum Black for low voltage microscale electrode neurostimulation
Sensors and Actuators B-chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
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layer by layer nanoassembly of iridium oxide Platinum Black for low impedance high charge injecting microelectrode applications
International Conference on Micro Electro Mechanical Systems, 2012Co-Authors: S. Yamagiwa, A. Fujishiro, A. Ikedo, M. Ishida, T. KawanoAbstract:We report an electrode device with a low impedance and high charge injecting characteristics for a powerful application to micro/nano-scale electrophysiological measurements of neuron/cells. Due to the small effective electrode area, conventional microelectrodes exhibit high interfacial electrode impedance (∼10 MΩ at 1 kHz) and low charge injection characteristics, making the targeted cells impossible to record/stimulate. To overcome these limitations, we propose enhanced surface-area of an electrode with a low impedance material, based on layer-by-layer assembled iridium oxide (IrOx)/Platinum-Black (Pt-Black) with nano-scale roughness. The assembled nanorough-IrOx/Pt-Black electrode exhibits 2 times lower impedance and 2.4 times larger injection delivery capacity (Q CDC ) compared to a planer-IrOx electrode with the same size. Additionally, we fabricated nanorough-Ir/Pt-Black tipped microprobes and demonstrated in saline, while improved stimulating currents were observed.
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Layer-by-layer nanoassembly of iridium oxide/Platinum-Black for low impedance, high charge injecting microelectrode applications
2012 IEEE 25th International Conference on Micro Electro Mechanical Systems (MEMS), 2012Co-Authors: S. Yamagiwa, A. Fujishiro, A. Ikedo, M. Ishida, T. KawanoAbstract:We report an electrode device with a low impedance and high charge injecting characteristics for a powerful application to micro/nano-scale electrophysiological measurements of neuron/cells. Due to the small effective electrode area, conventional microelectrodes exhibit high interfacial electrode impedance (~10 MΩ at 1 kHz) and low charge injection characteristics, making the targeted cells impossible to record/stimulate. To overcome these limitations, we propose enhanced surface-area of an electrode with a low impedance material, based on layer-by-layer assembled iridium oxide (IrOx)/Platinum-Black (Pt-Black) with nano-scale roughness. The assembled nanorough-IrOx/Pt-Black electrode exhibits 2 times lower impedance and 2.4 times larger injection delivery capacity (QCDC) compared to a planer-IrOx electrode with the same size. Additionally, we fabricated nanorough-Ir/Pt-Black tipped microprobes and demonstrated in saline, while improved stimulating currents were observed.
Hirohito Sawahata - One of the best experts on this subject based on the ideXlab platform.
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Layer-by-layer assembled nanorough iridium-oxide/Platinum-Black for low-voltage microscale electrode neurostimulation
Sensors and Actuators B: Chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
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layer by layer assembled nanorough iridium oxide Platinum Black for low voltage microscale electrode neurostimulation
Sensors and Actuators B-chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
Rika Numano - One of the best experts on this subject based on the ideXlab platform.
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Layer-by-layer assembled nanorough iridium-oxide/Platinum-Black for low-voltage microscale electrode neurostimulation
Sensors and Actuators B: Chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
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layer by layer assembled nanorough iridium oxide Platinum Black for low voltage microscale electrode neurostimulation
Sensors and Actuators B-chemical, 2015Co-Authors: S. Yamagiwa, A. Fujishiro, M. Ishida, Hirohito Sawahata, Rika Numano, T. KawanoAbstract:Abstract Electrical neural stimulating electrodes play an important role in medical applications and improving health/medical conditions. However, size reduction for low-invasive electrodes creates issues with high electrolyte/electrode interfacial impedance and low charge-injection characteristics, which makes it impossible to stimulate neurons/cells. To overcome these limitations, we propose an electrode material for low-voltage microscale electrode neurostimulation that combines the advantages of low impedance of iridium oxide (IrOx) with the enhanced surface area of Platinum Black (Pt-Black). Based on a simple, rapid, low-temperature electroplating process, herein a low impedance and high charge-injection electrode is fabricated by a layer-by-layer assembly of IrOx/Pt-Black with nanoscale roughness. The assembled nanorough-IrOx/Pt-Black electrode has an impedance of 32 Ω cm2 at 1 kHz and a charge-injection delivery capacity (QCDC) of 46.7 mC cm−2, which are 0.5 and 2.4 times the values for the same-sized IrOx/flat-Pt electrode, respectively. The stimulation capability of the nanorough-IrOx/Pt-Black plated microelectrode is confirmed by in vivo stimulations of the sciatic nerve of a mouse. The threshold voltages of 8-μm-diameter and 11-μm-diameter electrodes are 700 mV and 300 mV, respectively. However, increasing the diameter of high QCDC nanorough-IrOx/Pt-Black can further reduce the stimulation voltage. Consequently, nanorough-IrOx/Pt-Black is applicable to low-voltage microscale electrode neurostimulations for powerful in vivo/in vitro electrophysiological measurements.
Chunsheng Yang - One of the best experts on this subject based on the ideXlab platform.
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Implantable electrode array with Platinum Black coating for brain stimulation in fish
Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems, 2013Co-Authors: Chuan Zhang, Bin Yang, Hong-chang Tian, Xiao-yang Kang, Jingcheng Du, Chunsheng YangAbstract:Electrical stimulation of certain part of the neural tissue could evoke specific functional response. The interface plays an important role in stimulation process. Tungsten wire electrodes have long been used as an ideal interface for neural signal recording and stimulation. In this work, an electrode array with good electrochemical property and biocompatibility was successfully fabricated in a novel and convenient way. A PDMS electrode holder was made to fix the electrodes with certain distance. To achieve a better stimulation effect, a Platinum Black coating was electroplated, and the electrochemical properties of the electrode were tested. Tests results of the impedance and charge injection capacity showed great improvement in electrochemical property. To test the durability of the Platinum Black coating, the electrode was dealt with ultrasound vibration for 10 min and then re-tested for charge storage capacity lost. The array was then implanted into the midbrain of crucian carp by a surgical procedure. A stimulation pulse was applied in order to elicit a change in locomotion. By stimulating the midbrain part of the fish brain, both side turning movements were observed. Also, this work provides the fundamental experiment for the development of bio-robotic fish.
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Mechanical and electrical stability of parylene-based Platinum-Black coated wire microelectrode for implantable applications
Journal of Applied Electrochemistry, 2012Co-Authors: Yuefeng Rui, Chunsheng Yang, Bin Yang, Jingquan Liu, Daixu WeiAbstract:In this paper, a parylene-based Platinum-Black coated wire microelectrode with multi-electrode sites for neuromuscular stimulation was fabricated. The electrodes with tunable electrode site position, quantity, and width will achieve multi-stimulation during functional electrical stimulation. The Platinum-Black coating was electroplated on electrode sites by applying a current pulse train in chloroplatinic acid solution (H2PtCl6) under ultrasonic bath, which contributed to achieve excellent mechanical and electrical stability of the microelectrode. After electroplating, the 90 % of impedance reduction and 13 times of cathodic charge storage capacity increase were achieved. Finally, the mechanical and electrochemical stability test, the passive soaking test, and the bending test were performed. The results showed that the Platinum-Black coated wire microelectrode had good stability after 5 min of ultrasonic vibration and 122 h of current pulses stimulation. After soaking in 0.9 % saline solution at 87 °C for 8 months, the average impedance at 1 kHz just increased by 1.6 kΩ. The bending test (with maximum bending angle of 90°) also showed that there was a little change in the electrochemical characteristics of the electrode. This parylene-based Platinum-Black coated wire microelectrode will be promising for facial prosthesis applications.
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parylene based implantable Platinum Black coated wire microelectrode for orbicularis oculi muscle electrical stimulation
Biomedical Microdevices, 2012Co-Authors: Bin Yang, Keyong Li, Chunsheng YangAbstract:A novel and simple process was proposed to fabricate a parylene-based Platinum-Black coated wire microelectrode for orbicularis oculi muscle electrical stimulation. Compared with conventional microelectrodes, wire microelectrodes would enable smaller wounds, increased ease of implantation, and improved cosmesis. Meanwhile, the circumferential electrode sites of this wire microelectrode fabricated by lift-off process would contribute to fully contact with tissue and reduction of electrode-tissue interface impedance. The width and the amount of electrode sites could be decided by the thickness and the amount of sacrificial layer, respectively. The Platinum-Black coatings were electroplated on electrode sites by applying a current pulse train in chloroplatinic acid solution with ultrasonic bath for further electrode-tissue interface impedance reduction and good mechanical stability of coatings. Electrode impedance at 1 kHz has been significantly reduced by 90%, and the cathodic charge storage capacity (CSCc) has been increased by 13 times. In addition, hematoxylin-eosin (HE) staining section of muscle demonstrated the good biocompatibility of this electroplated Platinum-Black. By applying a charge imbalanced biphasic stimulation waveform for orbicularis oculi muscle stimulation, the rabbits with facial paralysis rehabilitated the function of closing eyes. This kind of microelectrode will be promising for neuromuscular applications.