Reinforcing Silk Scaffolds with Silk Particles

• Published in: Macromolecular bioscience 2010-06, Vol.10 (6), p.599-611
• Main Authors: Rajkhowa, Rangam, Gil, Eun Seok, Kluge, Jonathan, Numata, Keiji, Wang, Lijing, Wang, Xungai, Kaplan, David L.
• Format: Article
• Language: English
• Subjects: Animals; Applied sciences; biodegradable; Biological and medical sciences; Biomaterials; Bombyx; Chemical Precipitation; composites; Compressive modulus; Degradation; Exact sciences and technology; Freeze Drying; Materials Testing; Mechanical Phenomena; Medical sciences; Natural polymers; Particle Size; particles; Physicochemistry of polymers; Porosity; Proteins; Reinforcement; Scaffolds; Silk; Silk - chemistry; Silk - standards; Solubility; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgical implants; Technology. Biomaterials. Equipments
• ISSN: 1616-5187; 1616-5195; 1616-5195
• DOI: 10.1002/mabi.200900358

Silk fibroin is a useful protein polymer for biomaterials and tissue engineering. In this work, porogen leached scaffolds prepared from aqueous and HFIP silk solutions were reinforced through the addition of silk particles. This led to about 40 times increase in the specific compressive modulus and the yield strength of HFIP‐based scaffolds. This increase in mechanical properties resulted from the high interfacial cohesion between the silk matrix and the reinforcing silk particles, due to partial solubility of the silk particles in HFIP. The porosity of scaffolds was reduced from ≈90% (control) to ≈75% for the HFIP systems containing 200% particle reinforcement, while maintaining pore interconnectivity. The presence of the particles slowed the enzymatic degradation of silk scaffolds. In recent years, there has been increased interest in silk for biomedical applications. New composite macro‐porous 100% silk scaffolds were prepared by salt leaching in which milled silk particles were used to reinforce a regenerated silk matrix. The mechanical properties of scaffolds increased significantly by particle reinforcement while porosity and pore interconnectivity were maintained.