Preparation of sulfonated silk fibroin for anti-coagulation material

Abstracts Here we report the anticoagulant property of Sulfonated Silk Fibroin (SSF) which was improved by sulfonation method. Chlorosulfonic acid was applied to modify the Silk Fibroin (SF) anticoagulant property by the preparation of the SSF. The SSF was prepared in the new technology that 50 °C, 0.2 g SF/ml chlorosulfonic acid and 15 h were optimized with the reaction temperature, special concentration ratio of the SF to the chlorosulfonic acid and the certain reaction time, respectively. Then the SF reaction solution was dialyzed, and freeze-dried to form the SSF. The different properties of the SF and the SSF have been revealed by Fourier Transform Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), X-ray Photoelectron Spectrometer (XPS), Gel Permeation Chromatography (GPC), X-ray Diffraction (XRD), Activated Partial Thromboplastin Time (APTT) etc. That the sulfonic acid groups were successfully induced into the SF molecular chains has also been verified. The SSF possessed the excellent performance on the APTT value, and it can be slowly released from the Poly(epsilon-caprolactone) (PCL) composite film. In conclusion, the SSF is the novel product modified by the chlorosulfonic acid directly, and it possesses the good anti-coagulation, resulting in that it can become one of candidates of anti-coagulation materials.