Facile Roll-to-Roll Production of Nanoporous Fiber Coatings for Advanced Wound Care Sutures

Abstract

Theranostic sutures are innovative ideas to enhance wound healing results by adding wound diagnostics and therapeutics to the typical sutures by functionalizing them with additional materials. Here, we present a new direct electrospinning method for the fast, continuous, inexpensive, and high-throughput production of versatile nanofibrous-coated suture threads, with precise control over various essential microstructural and physical characteristics. The thickness of the coating layer and the nanofibers' alignment with the thread's direction can be adjusted by the user by varying the spooling speed and the displacement between the spinneret needle and thread. To show the flexibility of our method for the range of material selection, the results of gelatin, polycaprolactone, silk fibroin, and PEDOT:PSS (poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)), which were the resulted nanofibers characterized by scanning electron microscope (SEM) imaging and conductivity tests. In a series of in vitro and ex vivo tests (pig skin), sutures were successfully tested for their flexibility and mechanical properties as weaving and knotting sutures and their biocompatibility with a keratinocyte cell line. For the temperature-based drug-releasing, two fluorescent molecules as drug models with high and low molecular weight, fluorescein isothiocyanate-Dextran (20 kDa) and rhodamine B (470 Da), were used, and a steady release with an increment of the temperature to 37 °C over a 120 min was seen which is appropriate for bacterial treatment drugs. Given the advantages of the presented technique, it seems to have a promising potential to be used in future medical applications for wound closure and bacterial infection treatment via a temperature-triggered drug release strategy.