Structural characterization of silk-polyurethane composite material for biomaterials using solid-state NMR

Abstract

In this paper, we performed solid-state nuclear magnetic resonance (NMR) measurements, including T 1 H and T 1q , of silk fibroin (SF)/polyurethane (PU) composites to examine their possible use as a material for artificial vascular grafts. In the development of new artificial vascular grafts made from SF/PU, it is important to examine the miscibility of the composites and their molecular dynamics, because these properties are intimately involved in the resulting physical properties of the resulting vascular graft. The T 1 H measurements showed that the domain size of the SF/PU ¼ 1:1 composite is smaller than the domain size of the 1:10 and 1:2 composites, indicating that the molecular miscibility between SF and PU are partially in close proximity, particularly in the SF/PU ¼ 1:1 composite. Additionally, we observed that the molecular motion of the soft segment of PU in the SF/PU composites becomes slow, suggesting that the soft segment of PU interacts with SF to some extent. These analyses provided basic structural information for the development of silk-based artificial vascular grafts using PU.

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

“…It had shown to be highly miscible SF and PU, to maintain SF useful structure, and that it suggested to mix PU with SF to improve flexibility while largely maintaining tensile strength. 15 From this result, PU was selected to improve the flexibility of SF patch.…”

Structural investigations of polyurethane and silk‐polyurethane composite fiber studied by 13C solid‐state NMR spectroscopy

“…In order to study more about the miscibility of SF‐PU composite materials, the 1 H spin–lattice relaxation times in the laboratory frame (T 1 H ) were observed for the SF‐PU composite materials. The observations revealed that the molecular chains of SF and PU exist in close proximity of several tens of nanometers 60 . On the other hand, there are also some reports that specific interactions such as strong hydrogen bonding occurred between PU and SF in SF‐PU composite materials from the FT‐IR spectra 33,36,58 .…”

“…The observations revealed that the molecular chains of SF and PU exist in close proximity of several tens of nanometers. 60 On the other hand, there are also some reports that specific interactions such as strong hydrogen bonding occurred between PU and SF in SF-PU composite materials from the FT-IR spectra. 33,36,58 Thus, the aspect of the interaction between SF and PU seems to be dependent on the components of PU samples.…”

Silk fibroin/polyurethane patch implantation in hyperglycemic rat model

“…11 Some previous studies showed that SF and PU were considered to have compatibility, and SF/PU blended patch was superior to pure SF patch in terms of its flexibility, mechanical properties, biocompatibility, and cell adhesion rate. 12,13 Therefore, in order to improve the application of SF, we blended PU to SF. Our previous study, it showed that SF/PU was useful for using as a cardiac patch regarding the biocompatibility, intensity, and flexibility of the patch graft.…”