Powering devices goes skin deep

March 08, 2020

Soft and flexible materials can be used to ultrasonically charge bioelectronic implants, which could help to reduce the need for surgical treatment.

Electronic devices are increasingly used to remedy serious and long-term health problems, such as pacemakers to regulate heartbeat, electronic pumps that release insulin, and implantable hearing aids. Key design considerations for these components aim to minimize size and weight for patient comfort, and they ensure that the device is not toxic to the body.

Another stumbling block is how to power the devices. Batteries keep them working for a while, but changing the batteries demands invasive surgery. Ideally, the power source needs to be recharged wirelessly.

A collaborative study between the groups of materials scientist Husam Alshareef at KAUST and medical imaging expert Abdulkader A. Alkenawi at King Saud bin Abdulaziz University for Health Sciences reveals a way to remotely charge a battery using a soft, biocompatible material that absorbs sound waves passed through the body.

Hydrogels are made of long polymer molecules cross-linked to form a three-dimensional network that can hold a great deal of water. This gives hydrogels a flexible and stretchable texture, but it also means they are both electrical conductors and biocompatible, making them ideal for bioelectronic applications.

Kanghyuck Lee, lead author of the study, explains how the team combined polyvinyl alcohol with nanosheets of MXene, a transition-metal carbide, nitride or carbonitride. "Just as dissolving salt in water makes it conductive, we used MXene nanoflakes to create the hydrogel," says Lee. "We were surprised to find that the resulting material can generate electric power under the influence of ultrasound waves."

Their hydrogel, which they refer to as M-gel, generates a current when an applied pressure forces the flow of electrical ions in the water, filling the hydrogel. When this pressure is the result of ultrasound, the effect is called streaming vibration potential.

The KAUST team proved the concept by using a range of ultrasonic sources, including ultrasound tips found in many labs and the ultrasound probes used in hospitals for imaging. They were able to quickly charge an electrical device buried within several centimeters of beef.

"This is another example of the impressive potential of MXene hydrogels we've been developing in our laboratory for sensing and energy applications," said Alshareef.
-end-


King Abdullah University of Science & Technology (KAUST)

Related Ultrasound Articles from Brightsurf:

An integrated approach to ultrasound imaging in medicine and biology
Announcing a new article publication for BIO Integration journal. In this editorial, Co-Editor-in-Chief, Pingtong Huang considers an integrated approach to ultrasound imaging in medicine and biology.

PLUS takes 3D ultrasound images of solids
A two-in-one technology provides 3D images of structural defects, such as those that can develop in aircraft and power plants.

Scientists develop noninvasive ultrasound neuromodulation technique
Researchers from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences developed a noninvasive ultrasound neuromodulation technique, which could potentially modulate neuronal excitability without any harm in the brain.

World's first ultrasound biosensor created in Australia
Most implantable monitors for drug levels and biomarkers invented so far rely on high tech and expensive detectors such as CT scans or MRI.

Ultrasound can make stronger 3D-printed alloys
A study just published in Nature Communications shows high frequency sound waves can have a significant impact on the inner micro-structure of 3D printed alloys, making them more consistent and stronger than those printed conventionally.

Full noncontact laser ultrasound: First human data
Conventional ultrasonography requires contact with the patient's skin with the ultrasound probe for imaging, which causes image variability due to inconsistent probe contact pressure and orientation.

Ultrasound aligns living cells in bioprinted tissues
Researchers have developed a technique to improve the characteristics of engineered tissues by using ultrasound to align living cells during the biofabrication process.

Ultrasound for thrombosis prevention
Researchers established real-time ultrasonic monitoring of the blood's aggregate state using the in vitro blood flow model.

Ultra ultrasound to transform new tech
A new, more sensitive method to measure ultrasound may revolutionize everything from medical devices to unmanned vehicles.

Shoulder 'brightness' on ultrasound may be a sign of diabetes
A shoulder muscle that appears unusually bright on ultrasound may be a warning sign of diabetes, according to a new study.

Read More: Ultrasound News and Ultrasound Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.