Photo-synthesis of sensing silk fibroin fibers with double-network structures

Toughened fibers are highly desirable for a wide range of practical applications, particularly in biomedical and textile industries. Herein, robust silk fibroin fibers with a double-network (DN) structure were successfully fabricated using an in situ photo-polymerization process after swelling. The DN fibers were characterized in terms of morphology, secondary structure, alkali resistance, and tensile properties. These fibers demonstrated remarkable tensile strength in both dry and wet states, along with enhanced alkali resistance, making them highly suitable for demanding environments. Another key advancement in this study is the incorporation of a chromatic biosensor into the DN silk suture, enabling the fibers to undergo a visible blue-to-red color change upon exposure to bacterial strains, both to the naked eye and under a microscope. This color change is essential for bacterial sensing, enabling real-time detection and providing an effective tool for infection monitoring and biosensors in surgical sutures.