Surface Modification and Characterisation of Silk Fibroin Fabric Produced by the Layer-by-Layer Self-Assembly of Multilayer Alginate/Regenerated Silk Fibroin

Abstract

Silk-based medical products have a long history of use as a material for surgical sutures because of their desirable mechanical properties. However, silk fibroin fabric has been reported to be haemolytic when in direct contact with blood. The layer-by-layer self-assembly technique provides a method for surface modification to improve the biocompatibility of silk fibroin fabrics. Regenerated silk fibroin and alginate, which have excellent biocompatibility and low immunogenicity, are outstanding candidates for polyelectrolyte deposition. In this study, silk fabric was degummed and positively charged to create a silk fibroin fabric that could undergo self-assembly. The multilayer self-assembly of the silk fibroin fabric was achieved by alternating the polyelectrolyte deposition of a negatively charged alginate solution (pH = 8) and a positively charged regenerated silk fibroin solution (pH = 2). Finally, the negatively charged regenerated silk fibroin solution (pH = 8) was used to assemble the outermost layer of the fabric so that the surface would be negatively charged. A stable structural transition was induced using 75% ethanol. The thickness and morphology were characterised using atomic force microscopy. The properties of the self-assembled silk fibroin fabric, such as the bursting strength, thermal stability and flushing stability, indicated that the fabric was stable. In addition, the cytocompatibility and haemocompatibility of the self-assembled silk fibroin fabrics were evaluated. The results indicated that the biocompatibility of the self-assembled multilayers was acceptable and that it improved markedly. In particular, after the self-assembly, the fabric was able to prevent platelet adhesion. Furthermore, other non-haemolytic biomaterials can be created through self-assembly of more than 1.5 bilayers, and we propose that self-assembled silk fibroin fabric may be an attractive candidate for anticoagulation applications and for promoting endothelial cell adhesion for vascular prostheses.

Properties of chitosan matrix composites with hydroxyapatite and carbon nanotubes, and their use in bone tissue engineering

“…It is observed that in both the studies, [6][7][8]17 with only subtle increments of CNTs, mechanical properties of CHI polymer matrices can be substantially improved, and that both HA and CNTs are evenly distributed in CHI matrix.…”

“…The composites based on Hydroxyapatite, Carbon Nanotubes with Biopolymers are excellent candidates for application in bone grafts and coating of bone prostheses, due to their mechanical properties, to promote osteogenesis and reduce bacterial fixation. [6][7][8][9] The purpose of the manuscript is to analyze and compare data from the current state of the art of CHI matrix composites with HA and CNTs applied in bone tissue engineering.…”

Control of weft yarn or density improves biocompatibility of PET small diameter artificial blood vessels

“…As all biomaterials approved by the FDA exhibit no cytotoxicity, some of the more likely sources of problems associated with biomaterials may involve their structural parameters as well as the chemical structure of the material . As an approach to rectify these problems many attempts have been employed to change the structure of surface chemicals to promote cell adhesion and proliferation as achieved with the use of layer by layer or surface grafting . However, for a woven fabric, such as polyethylene glycol terephthalate (PET), the structural parameters seem to exert a greater impact upon cell adhesion than that of the chemical structure .…”

PCL films of varying porosity influence ICAM‐1 expression of HUVECs

“…Accordingly, a considerable amount of effort has been directed at improving the biocompatibility of biomaterials in order to reduce such complications. Some examples of these attempts have included a layer by layer assembly, surface grafting and alterations in surface morphology . Ranella et al, utilized the microstructure of nanosilicon materials as an approach to impact cell adhesion.…”

“…Some examples of these attempts have included a layer by layer assembly, surface grafting and alterations in surface morphology. [3][4][5][6][7][8][9] Ranella et al, 5 utilized the microstructure of nanosilicon materials as an approach to impact cell adhesion. With the use of a femtosecond laser, they produced silicon wafers with different surfaces that varied from smooth to very coarse.…”