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All-carbon-nanotube flexible multi-electrode array for neuronal recording and stimulation.

David-Pur M, Bareket-Keren L, Beit-Yaakov G, Raz-Prag D, Hanein Y - Biomed Microdevices (2014)

Bottom Line: The use of carbon nanotubes bestows the electrodes flexibility and excellent electrochemical properties.As opposed to contemporary flexible neuronal electrodes, the technology presented here is both robust and the resulting stimulating electrodes are nearly purely capacitive.Recording and stimulation tests with chick retinas were used to validate the advantageous properties of the electrodes and demonstrate their suitability for high-efficacy neuronal stimulation applications.

View Article: PubMed Central - PubMed

Affiliation: School of Electrical Engineering, Tel-Aviv University, Tel-Aviv, 6997801, Israel.

ABSTRACT
Neuro-prosthetic devices aim to restore impaired function through artificial stimulation of the nervous system. A lingering technological bottleneck in this field is the realization of soft, micron sized electrodes capable of injecting enough charge to evoke localized neuronal activity without causing neither electrode nor tissue damage. Direct stimulation with micro electrodes will offer the high efficacy needed in applications such as cochlear and retinal implants. Here we present a new flexible neuronal micro electrode device, based entirely on carbon nanotube technology, where both the conducting traces and the stimulating electrodes consist of conducting carbon nanotube films embedded in a polymeric support. The use of carbon nanotubes bestows the electrodes flexibility and excellent electrochemical properties. As opposed to contemporary flexible neuronal electrodes, the technology presented here is both robust and the resulting stimulating electrodes are nearly purely capacitive. Recording and stimulation tests with chick retinas were used to validate the advantageous properties of the electrodes and demonstrate their suitability for high-efficacy neuronal stimulation applications.

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Electrical recording and stimulation of chick retina with flexible CNT MEA. a Evoked activity using a biphasic cathodic first pulse (arrowhead). The large signal at t=0 is an artifact of the stimulation. b Firing rate of evoked activity at different stimulation intensities (3–10 nC). c Firing rate of evoked activity after synaptic blockers CNQX and APV application (stimulation was applied every 10 s). After 400 s no retinal ganglion cells activation is observed
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Fig4: Electrical recording and stimulation of chick retina with flexible CNT MEA. a Evoked activity using a biphasic cathodic first pulse (arrowhead). The large signal at t=0 is an artifact of the stimulation. b Firing rate of evoked activity at different stimulation intensities (3–10 nC). c Firing rate of evoked activity after synaptic blockers CNQX and APV application (stimulation was applied every 10 s). After 400 s no retinal ganglion cells activation is observed

Mentions: At day 14 the embryonic retina is still at an early developmental stage and clear spontaneous activity waves were recorded demonstrating the overall functionality of the device and the setup. We next tested the CNT electrodes suitability to evoke electrical activity in the retina tissue. Stimulation was achieved at currents as low as 4 μA (Fig. 4a and b) and stimulation pulse width of 1 ms. With nearly perfectly capacitive electrodes, these values are well within the limits of safe stimulation. The observed electrical response is typical for pre-synaptic cells activation. Validation of the synaptic processes was achieved with the use of the synaptic blockers 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and 2-amino-5-phosphonovaleric acid (APV). 400 s after the introduction of the synaptic blockers no retinal ganglion cell activation was measured (Fig. 4c).Fig. 4


All-carbon-nanotube flexible multi-electrode array for neuronal recording and stimulation.

David-Pur M, Bareket-Keren L, Beit-Yaakov G, Raz-Prag D, Hanein Y - Biomed Microdevices (2014)

Electrical recording and stimulation of chick retina with flexible CNT MEA. a Evoked activity using a biphasic cathodic first pulse (arrowhead). The large signal at t=0 is an artifact of the stimulation. b Firing rate of evoked activity at different stimulation intensities (3–10 nC). c Firing rate of evoked activity after synaptic blockers CNQX and APV application (stimulation was applied every 10 s). After 400 s no retinal ganglion cells activation is observed
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3921458&req=5

Fig4: Electrical recording and stimulation of chick retina with flexible CNT MEA. a Evoked activity using a biphasic cathodic first pulse (arrowhead). The large signal at t=0 is an artifact of the stimulation. b Firing rate of evoked activity at different stimulation intensities (3–10 nC). c Firing rate of evoked activity after synaptic blockers CNQX and APV application (stimulation was applied every 10 s). After 400 s no retinal ganglion cells activation is observed
Mentions: At day 14 the embryonic retina is still at an early developmental stage and clear spontaneous activity waves were recorded demonstrating the overall functionality of the device and the setup. We next tested the CNT electrodes suitability to evoke electrical activity in the retina tissue. Stimulation was achieved at currents as low as 4 μA (Fig. 4a and b) and stimulation pulse width of 1 ms. With nearly perfectly capacitive electrodes, these values are well within the limits of safe stimulation. The observed electrical response is typical for pre-synaptic cells activation. Validation of the synaptic processes was achieved with the use of the synaptic blockers 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and 2-amino-5-phosphonovaleric acid (APV). 400 s after the introduction of the synaptic blockers no retinal ganglion cell activation was measured (Fig. 4c).Fig. 4

Bottom Line: The use of carbon nanotubes bestows the electrodes flexibility and excellent electrochemical properties.As opposed to contemporary flexible neuronal electrodes, the technology presented here is both robust and the resulting stimulating electrodes are nearly purely capacitive.Recording and stimulation tests with chick retinas were used to validate the advantageous properties of the electrodes and demonstrate their suitability for high-efficacy neuronal stimulation applications.

View Article: PubMed Central - PubMed

Affiliation: School of Electrical Engineering, Tel-Aviv University, Tel-Aviv, 6997801, Israel.

ABSTRACT
Neuro-prosthetic devices aim to restore impaired function through artificial stimulation of the nervous system. A lingering technological bottleneck in this field is the realization of soft, micron sized electrodes capable of injecting enough charge to evoke localized neuronal activity without causing neither electrode nor tissue damage. Direct stimulation with micro electrodes will offer the high efficacy needed in applications such as cochlear and retinal implants. Here we present a new flexible neuronal micro electrode device, based entirely on carbon nanotube technology, where both the conducting traces and the stimulating electrodes consist of conducting carbon nanotube films embedded in a polymeric support. The use of carbon nanotubes bestows the electrodes flexibility and excellent electrochemical properties. As opposed to contemporary flexible neuronal electrodes, the technology presented here is both robust and the resulting stimulating electrodes are nearly purely capacitive. Recording and stimulation tests with chick retinas were used to validate the advantageous properties of the electrodes and demonstrate their suitability for high-efficacy neuronal stimulation applications.

Show MeSH
Related in: MedlinePlus