Facile synthesis of 3D silk fibroin scaffolds with tunable properties for regenerative medicine

Silk fibroin (SF) porous scaffolds provide mechanical support and biochemical signals to encourage cell attachment and modify biological performance. The available methods for the preparation of SF scaffolds are still required. The crosslinkers used are likely to impact the biocompatibility. Herein, water-insoluble SF scaffolds were prepared by physical methods. The phosphate solution promoted SF molecules aggregate from SF/heparin mixed solution. Then SF scaffolds were prepared in centrifuge tubes under different centrifugal speed. The phosphate was leached from the scaffolds, leaving porous structure. The centrifugal force produced shear-induced silk crystallinity to tune the mechanical performance like the natural silkworm gland. The relationship between performance and second structure of the scaffolds have been revealed by X-ray Diffraction (XRD) and deconvoluting Fourier Transform Infrared spectroscopy (FTIR). Due to changes in the β-sheet content, pore structure, mechanical strength, and drug-loaded behavior was adjustable. The scaffolds performed excellent on the Activated Partial Thromboplastin Time (APTT) value, and it can keep sustainable released for 7 days. The scaffolds prepared in mild environment showed tunable stiffness, good anticoagulation, and improved cell compatibility, suggesting its potential application in regenerative medicine.