The effect of a silk Fibroin/Polyurethane blend patch on rat Vessels

Abstract

Patch grafts are widely used in various kind of vascular surgeries such as detect repair or dilation of vascular stenosis. Expanded polytetrafluoroethylene (ePTFE) patches are flexible and handle well, but have shown problems with calcification as they are non-bioabsorbable and therefore permanently remain in the body. It is important to develop an alternative biocompatible patch. Silk fibroin (SF) was developed as a biocompatible material, but it lacks of the elasticity required for surgery as a patch. Polyurethane (PU) is also a well-known elastomer so this study focused on the SF and the PU blend materials with a weight ratio of 5:5 (SF/PU). To evaluate the SF/PU patch, the patches were implanted into the abdominal aortas of rats, using the ePTFE patch in the control group. Because it was more flexible the SF/PU patch was easier to implant than the ePTFE patch. At 1 week after implantation, the SF/PU patch had been infiltrated with cells and collagen fiber. The ePTFE control patch did not accumulate collagen fiber until 3 months and calcification occurred at 4 weeks. The SF/PU patch did not present any signs of calcification for 3 months. This study addressed the problems associated with using SF in isolation and showed that the SF/PU patch can be considered as a useful alternative to the ePTFE to overcome the problem of calcification.

Degradation and stabilization of polyurethane elastomers

“…Mg 2+ and Fe 3+ were shown to be able to inhibit pathological calcification in PU implants [533], with calcification also being overcome by blending a PU with silk fibroin [534].…”

Compatibility Evaluation of Non-Woven Sheet Composite of Silk Fibroin and Polyurethane in the Wet State

“…The SF/PU patch did not present any signs of calcification for three months. This study addressed the problems associated with using SF in isolation and showed that the SF/PU patch can be considered as a useful alternative to the ePTFE to overcome the problem of calcification [20]. Additionally, we focused on the effects of different SF concentrations in the SF/PU patch on its biological and physical properties.…”

Angioplasty Using 4-Hexylresorcinol-Incorporated Silk Vascular Patch in Rat Carotid Defect Model

“…Specifically, studies that employed SF as an artificial vessel confirmed it to have excellent hemocompatibility, cell viability, tissue integrity, and mechanical strength [42][43][44]. SF was also incorporated into cardiovascular patches purposed for vascular surgery [41,45]. Additionally, an in vivo study confirmed SF to have favorable biological and physical properties, and that it can be effectively used in vessel reconstruction surgery [41].…”