They Hid an Entire Circuit Inside a Thread Thinner Than a Hair and It Actually Works

By printing 100,000 transistors into just one centimeter of fiber, the team from Fudan University in Shanghai has pushed miniaturization to a new level. The result is a new class of fibers that can process information locally, transforming basic textiles into intelligent, interactive materials.

Smart textiles have been in development for years, but they’ve remained largely limited to integrating sensors or power sources. This latest development goes far beyond those capabilities. Instead of attaching components to fabrics, the researchers have embedded full circuits directly inside the thread. That distinction is what may change everything, from how clothing is made to how surgeries are performed.

The integrated component, described as a “fiber integrated circuit” or FIC, brings advanced computing capabilities into the realm of wearable materials. Previously, only simple features like LEDs or basic sensors could be added into fabrics. Now, full analog and digital processing can be done inside the thread itself, thanks to these embedded transistors.

A Spiral Architecture Inside a 50-Micrometer Fiber

At the core of this innovation lies a clever multilayer spiral architecture. Scientists printed transistors onto an ultra-flat elastomer-based film using a conventional lithography process. This film was then densely protected and rolled into a spiral, forming the interior of the fiber. The entire structure measures only 50 micrometers in diameter, notably smaller than the average human hair, which is about 70 micrometers thick.

The fiber doesn’t just survive wear and tear, it thrives in it. The team tested it through extreme conditions: 30% stretching, 180-degree twisting per centimeter, 10,000 bending and abrasion cycles, and even being run over by a 15.6-ton truck. It kept working throughout. According to Futura Sciences, it even withstands around a hundred washing cycles without performance loss.

The manufacturing technique used is also a game-changer. Chen Peining, one of the study’s authors, stated that their production method is “highly compatible” with existing semiconductor industry tools. That compatibility removes a major roadblock that often slows the adoption of new technologies: scalability.

Toward Interactive Clothing and Tactile Interfaces

These fibers can do far more than light up or monitor temperature. The team behind the research envisions garments capable of displaying navigation cues, health data, or even videos—right on the sleeve. That kind of textile interactivity would mark a leap forward for wearable electronics.

In an interview Chen Peining described gloves made with these fibers as indistinguishable from regular fabric. Yet, they could “detect and reproduce the sensation of different objects,” offering tactile feedback in real time. Such feedback could prove useful in virtual reality environments or remote surgery.

The researchers also hinted at potential use cases such as smart clothing with responsive light patterns or fabrics that can react to touch inputs. The possibility of interacting directly with one’s garments to access information or perform tasks is no longer in the realm of science fiction.

Flexible Enough for Neurological Implants

The fiber’s flexibility and thinness could make it ideal for medical implants, especially in the brain. Researchers have suggested potential uses in treating Parkinson’s disease, epilepsy, or even recovering from strokes.

Chen Peining also revealed that collaboration is already underway with a hospital to explore cardiovascular surgery applications. That step suggests the technology is not just a lab curiosity, but a candidate for real-world medical deployment.

Because the fiber integrates full processing capabilities, it could enable closed-loop systems in implants, where data is collected, analyzed, and acted upon, all within a threadlike structure. That level of sophistication has typically required bulky hardware. Now, it might fit inside a strand of fabric.

This innovation, reported in Nature, positions fiber-based circuits as one of the most promising areas in the field of connected devices and medical technology.