Dry-jet wet spinning and encapsulating for preparing multifunctional fibers based on anti-Rayleigh-Plateau-Instability solution

Diverse functional alginate fibers have played irreplaceable roles in life science, precision measurement, etc., drawing considerable attention from numerous researchers. However, further application of multifunctional fibers is greatly restricted by the preparation efficiency and the flexibility of equipment. Herein, modified anti-Rayleigh-Plateau-Instability sodium alginate solution filament and homemade piezoelectric ejector have been prepared to develop an efficient dry-jet wet spinning and encapsulating system for preparing functional fibers. This method has two working modes, which can readily realize the fabrication of conventional hollow fibers or fibers wrapping super large bubbles and functionalized fibers encapsulating reagents with on-demand size (ranging from 1 to 100 µm) and interval distance (ranging from several microns to a few centimeters) with excellent flexibility. Furthermore, the fiber size can be facilely tuned by regulating the flow rate and the rolling speed, up to 1 m s −1 , higher than all the wet spinning techniques ever reported. Functional reagents with different sizes and shapes have been encapsulated in fibers to verify the feasibility and practicality of this approach, demonstrating the potential for further applications in drug delivery, even cell encapsulation and culture.