Microfluidic wet spinning of antibacterial collagen composite fibers supported by chelate effect of tannic acid with silver ions

In this work, we reported the preparation of a novel type of collagen composite fiber with antibacterial properties by utilizing the hydrodynamic focusing effect of the multichannel microfluidic chip and microfluidic wet spinning technology (MWST). Specifically, tannin (TA)-grafted collagen solution was used as the precursor, ethanol anhydrous was used as the sheath flow, and AgNO3 solution was used as the spacer flow between the precursor and the sheath flow. The morphologies, structures, and properties of obtained collagen composite fibers were seriously analyzed. These results indicated that TA can not only form strong crosslinking networks of hydrogen bonds with collagen fibrils, but also chelate with Ag+, thus resulting in a synergistic enhancement of the mechanical properties, thermal stability, and antibacterial properties of collagen/TA-Ag composite fibers. These collagen composite fibers with excellent mechanical properties and antibacterial properties might have potential applications in the surgical suture field.