A Multichannel Flexible Optoelectronic Fiber Device for Distributed Implantable Neurological Stimulation and Monitoring

Abstract

Optical fibers made of polymeric materials possess high flexibility that can potentially integrate with flexible electronic devices to realize complex functions in biology and neurology. Here, a multichannel flexible device based on four individually addressable optical fibers transfer‐printed with flexible electronic components and controlled by a wireless circuit is developed. The resulting device offers excellent mechanics that is compatible with soft and curvilinear tissues, and excellent diversity through switching different light sources. The combined configuration of optical fibers and flexible electronics allows optical stimulation in selective wavelengths guided by the optical fibers, while conducting distributed, high‐throughput biopotential sensing using the flexible microelectrode arrays. The device has been demonstrated in vivo with rats through optical stimulation and simultaneously monitoring of spontaneous/evoked spike signals and local field potentials using 32 microelectrodes in four brain regions. Biocompatibility of the device has been characterized by behavior and immunohistochemistry studies, demonstrating potential applications of the device in long‐term animal studies. The techniques to integrate flexible electronics with optical fibers may inspire the development of more flexible optoelectronic devices for sophisticated applications in biomedicine and biology.

Soft Bioelectronics Based on Nanomaterials

“…For example, Yu et al developed a multichannel device that consists of flexible optical fibers, a flexible microelectrode array, and a wireless circuit (Figure 23E). 899 The flexible microelectrode array, made of stacked layers of PI/Cu/PI, was conformally integrated onto a curved optic fiber using the transfer printing technique (Figure 23F). Also, the surface of the electrode was modified with AuNPs to achieve high chemical stability and low contact impedance (Figure 23G).…”

“…(H) Optical image of a rat implanted with the optoelectronic device on brain, with spontaneous spike detected from the ventral hippocampus of a mouse (inset). (E–H) Reproduced with permission from ref . Copyright 2021 John Wiley and Sons.…”

Recent Advances in Printing Technologies of Nanomaterials for Implantable Wireless Systems in Health Monitoring and Diagnosis

“…Reproduced with permission. [ 62 ] Copyright 2020, Wiley‐VCH GmbH. b) Soft heart volume monitoring device conformally interfacing with an epicardial surface, enabled by compositing nanostructured Au–TiO 2 and PDMS.…”

“…Figure 3a shows a flexible optoelectronic device, consisting of flexible fibers, microelectrodes, and a miniaturized wireless circuit. [ 62 ] Each microelectrode array contains 8 µm thick PI/Cu/PI layers, whose surface is modified with AuNPs for improved chemical stability and reduced contact impedance in the brain tissues. The effective integration of the flexible microelectrodes with PMMA optical fibers (250 µm in diameters) by a transfer printing provides programmable optical stimulation in selective wavelengths, guided by the optical fibers.…”

Freestanding 3D Metallic Micromesh for High‐Performance Flexible Transparent Solid‐State Zinc Batteries

“…Flexible transparent electronics (FTEs) such as flexible transparent touch screens, [1] intelligent wristbands, wearable sensors, [2,3] electronic skins, [4,5] implantable medical devices, [6] and bendable smartphones have made remarkable progress in both industry and academia in recent years. The flexible transparent extensively used transparent conductive material with outstanding optical and electrical properties.…”