Spinning continuous high-strength bacterial cellulose hydrogel fibers for multifunctional bioelectronic interfaces

Abstract

Ionic conductive hydrogel fibers have attracted much attention as ideal optoelectronic physiological probes. However, their application is limited by their biocompatibility problem caused by the dependence on high-concentration ions, poor mechanical properties due to swelling, and continuous preparation. Here, we prepared a pure natural bacterial cellulose hydrogel fiber (BCHF) by a simple continuous wet-spinning method without any additional cross-linking step. The hydrogel fiber exhibits an excellent tensile strength of 3.74 MPa as well as a high-water content of 87% with no swelling properties. It can also maintain 90% of its original strength after being soaked in water for 14 days. The hydrogel fiber also integrates good bio-ion conductivity and light-guiding performance, and it can be directly used as a pure natural nanofluidic device without packaging for the detection of trace neurotransmitters. The strategy of achieving multifunctional hydrogel fibers will open up a new route for the development of next-generation neural interfaces.