Silk fibroin micro-particle scaffolds with superior compression modulus and slow bioresorption for effective bone regeneration

Abstract

Silk fibroin (SF), a natural polymer produced by Bombyx mori silkworms, has been extensively explored to prepare porous scaffolds for tissue engineering applications. Here, we demonstrate, a scaffold made of SF, which exhibits compression modulus comparable to natural cancellous bone while retaining the appropriate porosities and interconnected pore architecture. The scaffolds also exhibit high resistance to in-vitro proteolytic degradation due to the dominant beta sheet conformation of the SF protein. Additionally, the scaffolds are prepared using a simple method of microparticle aggregation. We also demonstrate, for the first time, a method to prepare SF micro-particles using a Hexafluoroisopropanol-Methanol solvent-coagulant combination. SF microparticles obtained using this method are monodisperse, spherical, non-porous and extremely crystalline. These micro-particles have been further aggregated together to form a 3D scaffold. The aggregation is achieved by random packing of these microparticles and fusing them together using a dilute SF solution. Preliminary in-vitro cell culture and in-vivo implantation studies demonstrate that the scaffolds are biocompatible and they exhibit the appropriate early markers, making them promising candidates for bone regeneration.

In vitro study of novel microparticle based silk fibroin scaffold with osteoblast-like cells for load-bearing osteo-regenerative applications

“…SF-scaffold has been prepared as per the protocol mentioned in our patent applications. 29,30 In brief, 4 mL syringe was lled with the SF-HFIP solution. A syringe pump with an infusion rate of 1 mL min À1 was used and the drops of SF-HFIP solution were collected in a stirred methanol coagulant bath.…”

“…26 We have recently developed novel processing protocols to produce unique 3D scaffolds of silk broin using SF micro-particles. 29,30 Here, the SF micro-particles are produced by collection of drops of SF solution in a methanol bath. These micro-particles are then fused together using a dilute solution of SF in water.…”

Graphene Oxide Reinforcing Genipin Crosslinked Chitosan-Gelatin Blend Films

“…When developing new biomaterials, natural polymers are often preferred to other classes of materials, as a result of their higher biocompatibility and similarities to human body constituents. For instance, some of the most popular natural biopolymers are chitosan [2], collagen [3] and gelatin [4], hyaluronic acid [5], sodium alginate [6,7], nanocellulose [8] and silk fibroin [9].…”

Effects of polyethylene glycol content on the properties of a silk fibroin/nano-hydroxyapatite/polyethylene glycol electrospun scaffold

“…The tting results were identied by spectral band, and the relative contents of random coils, ahelixes, b-turns, and b-sheets were calculated. 24 The hydrophilicity of the scaffolds was analyzed by contact angle measurements in contact angle apparatus (Dataphysics, Filderstadt, Germany).…”