In recent decades, due to the importance of properties such as: biocompatibility, biodegradability and environmental pollution reduction, the demand for biopolymer use has increased and interest is growing in the development of bio products. One of the biopolymers of interest to researchers is lignin, which has been reported in medicine due to the multifunctional properties of this polymer. In previous research, the antioxidant, antibacterial, UV-absorbing properties of this polymer have been mentioned and have been considered as a drug release. Other research to date has focused on the production of lignin nanofibers, and there is no report on the production of continuous twisted threads. continuous twisted yarn of lignin have more strength than its web nanofibers and can be used for specific performance with nanoparticles or drugs. In this study, nylon-lignin-polyethylene oxide suture was produced by electrospun technique and compared with nylon suture for mechanical properties. In order to produce nylon-lignin-polyethylene oxide nanofibers, electrospinning conditions such as polymer solution concentration, voltage, feed rate, distance between two nozzles and distance between nozzle and collector were optimized. Then the mechanical properties, including: strength of with and without knot sutures , were compared with two surgical knots (square knot and surgeon knot) in nylon-lignin-polyethylene oxide and nylon sutures. Subsequently, by adding the drug to the nylon-lignin-polyethylene oxide nanofibers, the lignin drug delivery properties was investigated in the sutures. Chemical properties of sutures were investigation by FTIR spectroscopy, and degradation rate in lignin-nylon-polyethylene oxide sutures was determined. The morphology of the nanofiber fracture in sutures was studied using FESEM images after mechanical testing.
