Production and Characterization of Nanofibrous Yarn Containing Lignin and Feasibility Study of Its Use as a Drug Eluting Suture

Hypothesis: Nanofibrous yarns produced from twisted strings of electrospun polymers like nylon showed acceptable mechanical properties as sutures. Using biopolymers such as lignin with interesting properties like biocompatibility, antioxidant, anti-bacterial, and drug delivery ability in the form of nanofibrous yarns could improve suture yarn properties. Nanofibrous yarns containing lignin could be used as biocompatible drug delivery suture yarn when having an acceptable strength.Methods: Nylon nanofibrous yarn, nylon-lignin-polyethylene oxide (N/L/P) hybrid nanofibrous yarn and its drug-loaded form were produced using the electrospinning method. The electrospinning conditions were optimized and the mechanical properties of the produced yarn were compared to a nanofibrous nylon yarn. The strength of knotted hybrid yarn (square knot and surgeon knot) with three different twist levels was examined and compared with each other. The presence of lignin and drug in N/L/P nanoyarn was proved using FTIR spectroscopy. The morphology of the produced yarn, its rupture mechanism, and degradation are studied by FESEM microscopy. The degradation rate of yarn was examined in a phosphate buffer medium. Drug delivery properties and drug release mechanisms are also investigated by loading a drug in N/L/P nanoyarn. Findings: Statistical comparison between N/L/P and nylon nanofibrous yarn showed that there is no significant difference in their strength. The rupture test showed that the hybrid nanoyarn has a two-stage rapture compared to the single-stage rapture of nylon nanoyarn. The hybrid yarn showed a degradation percentage of 46.13% in 60 min, while the drug release from the drug-loaded yarn was about 97% after 4 h. In conclusion, the results showed that the N/L/P nanofibrous yarn can be used as a drug delivery suture with good mechanical strength and a proper drug release profile for a short period of time.