Spiral-Transformed Soft Fibers Enabling High-Density Multimodal Bioelectronic Sensing and Stimulation

Abstract

The development of multimodal bioelectronic fibers has been hindered by several persistent challenges. Existing fiber-based devices are often mechanically rigid, suffer from low spatial precision in component arrangement, and exhibit limited functionality with sparse integration density. These shortcomings largely stem from the intrinsic difficulty of incorporating multiple microfabricated components into one-dimensional fiber geometries, where the curved, slender structures are fundamentally incompatible with conventional planar microfabrication techniques such as photolithography. Consequently, the applications of such fibers have remained narrow in scope. Recently, Bao’s team introduced a “spiral transformation” strategy that overcomes the structural and fabrication bottlenecks. By rolling two-dimensional thin films containing microfabricated devices into one-dimensional soft fibers, this method enables precise spatial control over the longitudinal, angular, and radial distribution of functional elements. The resulting Spiral-NeuroStrings (S-NeuroStrings) achieve unprecedented integration density, multifunctionality, and mechanical compliance. Their biocompatibility with soft and dynamic tissues is demonstrated through postoperative multimodal motility mapping and tissue stimulation in awake pigs, as well as long-term, multi-channel single-unit neural recordings in mice. Notably, the S-NeuroStrings is scalable to a density of 1280 functional units within 230-μm fiber, underscoring its transformative potential for minimally invasive, multimodal bioelectronic interfaces.

Keywords

Bioelectronic fibers / Spiral transformation / Multimodal sensing / Neural interfaces / Soft electronics

References

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Funding

Suzhou Institute of Nanotechnology, Chinese Academy of Sciences(E1552102)

Key Technologies Research and Development Program of Anhui Province(2022YFA1203304)

National Natural Science Foundation of China(T2422028)

RIGHTS & PERMISSIONS

Donghua University, Shanghai, China