GHz Ultrasonic Chip-Scale Device Induces Ion Channel Stimulation in Human Neural Cells
Abstract

Emergent trends in the device development for neural prosthetics have focused on establishing stimulus localization, improving longevity through immune compatibility, reducing energy re-quirements, and embedding active control in the devices. Ultrasound stimulation can single-handedly address several of these challenges. Ultrasonic stimulus of neurons has been studied extensively from 100 kHz to 10 MHz, with high penetration but less localization. In this paper, a chip-scale device consisting of piezoelectric Aluminum Nitride ultrasonic transducers was engineered to deliver gigahertz (GHz) ultrasonic stimulus to the human neural cells. These devices provide a path towards complementary metal oxide semiconductor (CMOS) integration towards fully controllable neural devices. At GHz frequencies, ultrasonic wavelengths in water are a few microns and have an absorption depth of 10–20 µm. This confinement of energy can be used to control stimulation volume within a single neuron. This paper is the first proof-of-concept study to demonstrate that GHz ultrasound can stimulate neuronsin vitro. By utilizing optical calcium imaging, which records calcium ion flux indicating occurrence of an action potential, this paper demonstrates that an application of a nontoxic dosage of GHz ultrasonic waves$$(\ge 0.05\frac{W}{c{m}^{2}})$$$\left(\ge 0.05\frac{W}{c{m}^{2}}\right)$caused an average normalized fluorescence intensity recordings >1.40 for the calcium transients. Electrical effects due to chip-scale ultrasound delivery was more »

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10154066
Journal Name:
Scientific Reports
Volume:
10
Issue:
1
ISSN:
2045-2322
Publisher:
Nature Publishing Group
National Science Foundation
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1. Abstract

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2. Abstract

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3. Abstract

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4. Abstract

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5. Abstract

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