Conductive hollow hydrogel fibers toward high-sensitivity bio-textiles

• Published in: Cell reports physical science 2024-07, Vol.5 (7), p.102047, Article 102047
• Main Authors: Deng, Pengfei, He, Zijian, Shen, Yingnan, Mohammad, Noor Mohammad, Xu, Wenhui, Han, Bumsoo, Li, Tian
• Format: Article
• Language: English
• Subjects: bio-interface; bioelectronics; breathability; co-axial printing; deformation sensors; energy harvesting; hollow fibers; human-machine interaction; hydrogel textile; wearable devices
• ISSN: 2666-3864; 2666-3864
• DOI: 10.1016/j.xcrp.2024.102047

Conductive hydrogels are becoming valuable in creating soft, flexible interfaces for biological tissue sensing due to their bio-compatibility and tissue-like mechanical properties. However, when tailored to epidermal sensors, they face low breathability and sensitivity issues, impacting long-term comfort and functionality. Addressing these issues, here we report sensing textiles from hollow conductive hydrogel fibers using co-axial microfluidic printing, allowing precise control of hollow channel diameters. The mesh-like textile demonstrates a sensitivity of 4.69 kPa−1, significantly outperforming the solid-structured counterparts (0.77 kPa−1). Moreover, the bio-textile demonstrates bio-compatibility, exhibiting no significant cytotoxic effects on human dermal fibroblasts after 3 days. To enhance durability and reusability, we integrate conductive fibers with metal wires for energy harvesting, achieving an open-circuit voltage output of ∼0.74 V. Notably, the voltage remains at ∼0.53 V even after dehydration. The high sensitivity, softness, and flexibility make our bio-textile a promising candidate for multifunctional sensing and energy harvesting in bio-interface devices. [Display omitted] •Hollow hydrogel fibers are controllably printed using co-axial microfluidics•Hollow structured fibers show 6× sensitivity compared to solid fibers•Bio-textile achieves high sensitivity and breathability for motion detection•Hydrogel fibers can be applied in energy harvesting Deng et al. develop a conductive breathable bio-textile with hollow hydrogel fibers using co-axial microfluidics. This hollow structured textile offers 6 times the sensitivity of the solid counterparts and can be used for motion detection and energy harvesting. This advancement promises improved comfort and functionality in wearable sensors and bio-interface applications.