Wearable health devices are becoming an important part of modern healthcare. Smartwatches, skin patches, and flexible sensors can continuously monitor signals such as heart activity, muscle movement, and other biological information. These devices can help doctors and researchers understand a person's health without requiring constant hospital visits.
However, there is one major challenge: movement can create unwanted noise in the signals recorded by wearable devices.
A new material developed by Zhou and a team of researchers could offer a promising solution. Their work focuses on creating a special supramolecular organohydrogel that can absorb mechanical disturbances over a much wider range than conventional materials. The technology could help wearable bioelectronics record cleaner and more reliable biological signals, even when the wearer is moving.
Why Motion Is a Problem for Wearable Sensors
Wearable sensors need to remain in close contact with the skin. This allows them to detect tiny electrical signals produced by the body. For example, an electrocardiogram (ECG) sensor measures the electrical activity of the heart.
The problem is that the human body rarely stays completely still.
Walking, running, stretching, breathing, or even small changes in the position of a sensor can produce mechanical disturbances. These disturbances can enter the recorded signal and appear as motion artifacts.
Motion artifacts can make a biological signal difficult to interpret. In some cases, the unwanted noise can be much stronger than the biological signal researchers are trying to measure.
Electronic systems can sometimes remove this noise using software and signal-processing techniques. But relying heavily on post-processing has limitations. If the original signal is badly contaminated, important information may already be lost.
This creates a need for materials that can prevent mechanical noise from reaching the sensor in the first place.
The Problem With Conventional Damping Materials
Researchers have previously used soft and flexible materials to reduce mechanical vibrations. These materials often contain structures that can absorb mechanical energy.
However, conventional damping materials usually depend on a limited number of viscoelastic relaxation mechanisms.
In simple terms, relaxation describes how a material responds when it is stretched, compressed, or disturbed and then gradually releases the stored mechanical energy.
The problem is that mechanical noise produced by human movement is not limited to one speed or one type of vibration. It can occur across many different frequencies and timescales.
A material that works well at one frequency may perform poorly at another. Temperature can also affect the behavior of conventional damping materials, making them less reliable in different environments.
The researchers therefore wanted to create something fundamentally different: a material capable of dissipating mechanical energy continuously across a broad range of frequencies and temperatures.
Creating a Dissipation Continuum
Zhou and the research team addressed this challenge by engineering what can be described as a dissipation continuum inside a supramolecular organohydrogel.
The material combines a polymer network with a fluid component. Instead of depending on one isolated mechanism to absorb mechanical energy, the researchers designed a special gradient layer at the boundary between the fluid and the polymer.
This boundary contains nanoscale confinement, which changes how the fluid behaves.
Inside this confined environment, the fluid can undergo fast viscous movement, while the polymer network responds more slowly through the movement of its molecular segments.
The researchers designed these two different types of motion to interact.
A Dynamic Bridge Between Fast and Slow Motion
One of the most interesting aspects of the material is the way it connects different timescales of mechanical movement.
The confined fluid responds quickly to mechanical disturbances. The polymer network, in contrast, responds more slowly.
The specially engineered gradient layer acts like a dynamic bridge between these two behaviors.
Instead of having only a few separate relaxation processes, the material creates a much more continuous range of relaxation times.
This means that when mechanical energy enters the material, different parts of the molecular structure can respond at different speeds.
The result is a broader ability to absorb and dissipate mechanical energy.
This approach is particularly useful for wearable electronics because movement-related noise is naturally complex. A person walking produces mechanical disturbances that are different from those created by running, stretching, or simply moving an arm.
A material with a continuous relaxation spectrum can potentially respond to many of these disturbances instead of being optimized for only a narrow range.
Impressive Performance Across Temperature and Frequency
The researchers reported strong damping performance from the new organohydrogel.
The material achieved a damping factor, represented by tan δ, of at least 0.8, across a wide temperature range from −30°C to 100°C.
It also maintained strong damping behavior across a broad frequency range of approximately 0.5 to 200 Hz.
These results are important because real-world wearable devices may operate under very different conditions.
A sensor used outdoors during cold weather may experience very different temperatures from one used inside a warm environment. At the same time, body movements can generate mechanical signals across a wide range of frequencies.
Maintaining damping performance across such a broad window could make wearable bioelectronics more robust.
Cleaner ECG Signals During Movement
The researchers demonstrated the practical value of their material by using it as an intrinsic noise-filtering interface for biological sensing.
In particular, the material helped produce artifact-free electrocardiogram recordings under mechanical disturbances.
This is an important achievement because ECG signals are widely used to monitor heart activity. If motion artifacts can be reduced directly at the sensor interface, wearable ECG devices could potentially collect more reliable information during everyday activities.
Instead of asking electronics to identify and remove every unwanted disturbance after the signal has been recorded, the material itself helps prevent mechanical noise from contaminating the signal.
Moving From Software Correction to Material-Level Protection
The significance of this research goes beyond one new hydrogel.
Traditional wearable sensing systems often follow a basic approach: collect the signal first and remove unwanted noise later using electronic filters or software algorithms.
The new strategy changes that approach.
By designing materials that can absorb mechanical disturbances before they interfere with the sensor, researchers are moving noise control from post-processing toward proactive material engineering.
This could reduce the burden on electronic signal-processing systems and potentially improve the quality of data collected by wearable devices.
It may also be useful for other types of bioelectronics that need to operate while the body is moving.
A Promising Future for Motion-Tolerant Bioelectronics
The development by Zhou and the research team demonstrates how molecular and material engineering can solve a practical problem in wearable healthcare technology.
The key innovation is the creation of a continuous relaxation spectrum through the interaction between a confined fluid and a polymer network. This allows the material to dissipate mechanical energy across a broad range of frequencies and temperatures.
As wearable healthcare continues to move toward continuous, real-time monitoring, sensors will need to work reliably in the messy and constantly changing environment of everyday life.
People walk, exercise, bend, stretch, and move throughout the day. Wearable devices must therefore be designed for movement rather than assuming that users will remain still.
This new organohydrogel offers a promising foundation for that goal. By acting as a built-in broadband noise filter, it could help wearable bioelectronics collect cleaner biological signals without depending entirely on complicated post-processing.
Ultimately, the research points toward a future in which the material surrounding a sensor does more than simply hold it against the skin—it actively protects the quality of the information being collected. Such innovations could play an important role in making next-generation wearable healthcare devices more accurate, reliable, and practical for everyday use.
Reference: Zhou, N., Liu, S., Lei, Z. et al. Broadband and wide-temperature dissipation continuum in a supramolecular damping organohydrogel for motion-tolerant bioelectronics. Nat Commun (2026). https://doi.org/10.1038/s41467-026-76626-w
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