Magnetoelectrics for Implantable Bioelectronics: Progress to Date

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 4, 2024

ConspectusThe coupling of magnetic and electric properties manifested in magnetoelectric (ME) materials has unlocked numerous possibilities for advancing technologies like energy harvesting, memory devices, medical technologies. Due to this unique coupling, the these can be tuned by an field; conversely, their polarization manipulated through a field.Over past seven years, our lab work focused on leveraging engineer implantable bioelectronics various neuromodulation applications. One main challenges is design miniaturized solutions that delivered with minimally invasive procedures yet receive sufficient power directly stimulate tissue or electronics perform functions communication sensing.Magnetoelectric ME strongest when driving field matches mechanical resonant mode. However, transducers typically have resonance frequencies >100 kHz, which too high direct as neurons only respond low (typically <1 kHz). We discuss two approaches been proposed overcome frequency mismatch: operating off-resonance rectification. The approach most common nanoparticles (MENPs) gigahertz range. In vivo experiments rat models shown MENPs could induce changes neural activity upon excitation <200 Hz fields. response latencies several seconds due weak regime.To responses millisecond precision, we developed methods rectify so drive at but still produce slowly varying voltages needed stimulation. first version stimulator combined transducer analog To create even smaller solutions, introduced metamaterial (MNM) exhibits self-rectification. Both designs effectively induced modulation less than 5 ms latency.Based experience testing rectified stimulators, found it challenging deliver precisely controlled therapy required clinical applications, given transducer's sensitivity external transmitter alignment. challenge, ME-BIT (MagnetoElectric BioImplanT), digitally programmable receives wireless data link.We further expanded utility technology applications require stimulation thresholds introducing DOT (Digitally Overbrain Therapeutic). voltage compliance up 14.5 V. demonstrated efficacy studies peripheral nerve epidural cortical stimulation.To improve systems adaptive enable network coordinated bidirectional system transmit from implant. greater miniaturization, way use same developing backscatter protocol.

Language: Английский

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Addressable and perceptible dynamic reprogram of ferromagnetic soft machines

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: March 6, 2025

Soft machines actuated by external magnetic fields have gained significant attention for their potential to interact with living organisms and complex environments. However, adaptability functionality are often limited rigid magnetization during operation. In this work, we introduce dynamically reprogrammable soft in situ reconfigurable profiles operations, achieved through the synergy of various fields. A flexible resonant circuit is integrated into machine body, enabling addressable perceptible heating specific regions via high-frequency varying frequencies. The body composed microbeads made from a low-melting-point alloy NdFeB microparticles. When heated, liquefies, allowing rotation microparticles under 40 mT pulsed programming field. Upon cooling, new configuration locked place. This reprogramming process equally effective single or multiple machines, versatile multi-pattern deformation individual cooperation ones. Furthermore, incorporating thermal actuation, demonstrate assembly robots. work may enable broad spectrum enhanced functionalities.

Language: Английский

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Endocisternal interfaces for minimally invasive neural stimulation and recording of the brain and spinal cord

Nature Biomedical Engineering, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 11, 2024

Language: Английский

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Scalable networks of wireless bioelectronics using magnetoelectrics

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 24, 2024

Networks of miniature bioelectronic implants would enable precise measurement and manipulation the complex distributed physiological systems in body. For example, sensing stimulation nodes throughout heart, brain, or peripheral nervous system more accurately track treat disease support prosthetic technologies with many degrees freedom. A main challenge to creating this type in-body network is fact that wireless power data transfer are often inefficient when communicating through biological tissues. This typically compounded as one increases number within network. Here, we show magnetoelectric a millimeter-sized where efficiency improves implanted devices increases. Using property, demonstrate networks battery-free bioelectronics ranging from 1 6 for 0.2% 1.3%, each node receiving 2.2 mW at distance cm. We use efficient robust proof-of-concept spinal cord stimulators cardiac pacing large animals. The scalability architecture enabled by provides platform building closed-loop next-generation electronic medicine.

Language: Английский

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Omnidirectional Wireless Power Transfer for Millimetric Magnetoelectric Biomedical Implants

IEEE Journal of Solid-State Circuits, Journal Year: 2024, Volume and Issue: 59(11), P. 3599 - 3611

Published: Oct. 11, 2024

Miniature bioelectronic implants promise revolutionary therapies for cardiovascular and neurological disorders. Wireless power transfer (WPT) is a significant method miniaturization, eliminating the need bulky batteries in today's devices. Despite successful demonstrations of millimetric battery-free animal models, robustness efficiency WPT are known to degrade significantly under misalignment incurred by body movements, respiration, heart beating, limited control implant orientation during surgery. This paper presents an omnidirectional platform implants, employing emerging magnetoelectric (ME) modality, "magnetic field steering" technique based on multiple transmitter (TX) coils. To accurately sense weak coupling miniature adaptively multi-coil TX array closed loop, we develop Active Echo (AE) scheme using tiny coil implant. Our prototype comprises fully integrated 14.2mm3 implantable stimulator embedding custom low-power System-on-Chip (SoC) powered ME film, with three-channel AE RX chip, mutual inductance cancellation. The achieves -161dBm/Hz input-referred noise 64dB gain tuning range reliably signal, offers fast polarity detection driver control. simultaneously enhances robustness, efficiency, charging WPT. Under 90° rotation from ideal position, our system 6.8× higher (PTE) than single-coil baseline. tracking error negligibly degrades PTE less 2%

Language: Английский

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A Miniature Batteryless Bioelectronic Implant Using One Magnetoelectric Transducer for Wireless Powering and PWM Backscatter Communication

IEEE Transactions on Biomedical Circuits and Systems, Journal Year: 2024, Volume and Issue: 18(6), P. 1197 - 1208

Published: Sept. 25, 2024

Wireless minimally invasive bioelectronic implants enable a wide range of applications in healthcare, medicine, and scientific research. Magnetoelectric (ME) wireless power transfer (WPT) has emerged as promising approach for powering miniature bio-implants because its remarkable efficiency, safety limit, misalignment tolerance. However, achieving low-power high-quality uplink communication using ME remains challenge. This paper presents pulse-width modulated (PWM) backscatter enabled by switched-capacitor energy extraction (SCEE) technique. The SCEE rapidly extracts dissipates the kinetic within transducer during ringdown period, enabling time-domain PWM backscatter. Various circuit techniques are presented to realize with low consumption. also describes high-order modeling transducers facilitate design analysis, which shows good matching measurement. Our prototyping system includes millimeter-scale implant fully integrated system-on-chip (SoC) portable transceiver bidirectional communication. is proven induce >50% amplitude reduction 2 cycles, leading 17.73 kbps data rate 0.9 pJ/bit efficiency. It achieves 8.5 × 10

Language: Английский

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