Microstructure Transitions and Dry-Wet Spinnability of Silk Fibroin Protein from Waste Silk Quilt

Abstract

With excellent biocompatibility and biodegradability, silk fibroin has been developed into many protein materials. For producing regenerated silk fibroin (RSF) fibers, the conformation transition of silk fibroin needs to be thoroughly studied during the spinning process. Since the many silk fabrics that are discarded comprise an increasing waste of resources and increase the pressure on the environment, in this paper, waste silk fiber was recycled in an attempt to prepare regenerated fibroin fiber by dry-wet spinning. Ethanol was the coagulation bath. The rheological properties of all the RSF solutions were investigated to acquire rheology curves and non-Newtonian indexes for spinnability analysis. Four stages of the spinning process were carried out to obtain RSF samples and study their conformation transitions, crystallization, and thermal properties by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction, and differential scanning calorimetry. Quantitative analysis of the FTIR results was performed to obtain specific data regarding the contents of the secondary structures. The results showed that higher concentration spinning solutions had better spinnability. As the spinning process progressed, random coils were gradually converted into β-sheets and crystallization increased. Among the different influencing factors, the ethanol coagulation bath played a leading role in the conformation transitions of silk fibroin.

Investigation of the biological activity, mechanical properties and wound healing application of a novel scaffold based on lignin–agarose hydrogel and silk fibroin embedded zinc chromite nanoparticles

“…S1B, ESI, † two observed absorption bands at 1654 cm À1 and 1535 cm À1 which are related to the C]O stretching vibration mode of amide I and the N-H bending vibration modes of amide II conrm the random coil conformation of SF. 40,41 Also, the broad absorption band around 3300 cm À1 indicates the bsheet conformation of SF. 42 .…”

Antibiotic‐based silk fibroin films for burn wound healing

“…The secondary structural changes in the films can be analyzed by the % absorbance of the peptide backbone. The peak assignment at 1622‐1637 cm −1 (amide I), 1515‐1525 cm −1 (amide II), and 1265 cm −1 (amide III) attribute to β‐sheet conformation 18 …”

Hydrothermal Effect on Mechanical Properties of Nephila pilipes Spidroin

“…The micelles model describes the formation of micelle structures through the interplay of the hydrophilic tails and hydrophobic cores of the spidroins and the induction of molecular-chain alignment upon the spinning process [10,11]. Taken together, the spidroin-aligned secondary structures (α-helices, random coil, and β-turns) govern the mechanical properties, e.g., hydrophobic antiparallel β-sheets that provide strength and β-spirals that offer the elasticity of the spider silks [9,11,[13][14][15][16][17].…”