In Situ Iodination Cross-Linking of Silk for Radio-Opaque Antimicrobial Surgical Sutures

The purpose of the study is to develop a method of imparting radio-opacity to the silk fibers by stepwise 2,5-dimethoxy-2,5-dihydro-furan (DMDF)–iodine cross-linking reaction for suture fabrication with mechanical properties abiding with U.S. pharmacopeia guidelines along with non invasive imaging advantage in postoperative follow-up. Silk fibers isolated from Bombyx mori were cross-linked with suitable concentration of DMDF linked with iodine under elevated temperature and pressure. Cross-linked fibers knitted into sutures were subjected to further testing.Computed tomography (CT) images on day 28 of in vivo studies showed mean radio-opacity value (MRV) of 213 ± 19.46 compared to the vertebral bone having value of 254.66 ± 0.51. Modified silk sutures demonstrated several advantages like high tensile strength (626 ± 23.3 MPa) and knot strength (388.6 ± 16.8 MPa) besides antimicrobial property. Encouraging preliminary in vitro and in vivo biocompatibility studies advocate the potential use of modified suture material in cardiac surgery, aneurysmal embolization surgeries, and arterio-venous occlusion surgeries.