Silk Powder from Cocoons and Woven Fabric as a Potential Bio-Modifier

Abstract

Silk, as a protein fiber characterized by high biocompatibility, biodegradability, and low toxicity, is mainly used as textile structures for various purposes, including for biological applications. The key issue for unlimited silk applicability as a modifier is to prepare its relevant form to cover or introduce to other materials. This study presents silk powder fabrication from Bombyx mori cocoons and non-dyed silk woven fabric through cryogenic milling. The cocoons were milled before and after the degumming process to obtain powders from raw structures and pure fibroin. The powder morphology and composition were analyzed using scanning electron microscopy and energy dispersive spectroscopy. The influence of the milling on the silk structure was studied using infrared and Raman spectroscopies, indicating that silk powders retained dominant β-sheet structure. The powders were also analyzed by differential scanning calorimetry and thermogravimetric techniques. The thermal endothermic peak and onset temperature characteristic for silk decomposition shifted to the lower values for all powders, indicating less thermal stability. However, the process was found to be an efficient way to obtain silk powders. The new milled form of silk can allow its introduction into different matrices or form coatings without using any harsh solvents, enriching them with new features and make more biologically friendly.

Multifunctional silk textile composites functionalized with silver nanowires

“…FTIR spectra were measured for pure silk fabric, silk fabric functionalized with PDA and PDA with about 3 and 10 g/m 2 of AgNWs (Figure 2a‐d). The main typical bands of fibroin were noted for pure and coated silk fabrics at the maximum of 1620, 1512, and 1262 cm −1 indicating β‐sheets crystallites of amide I, II, and III, respectively 20 . The band at a maximum of 1228 cm −1 corresponding to a random coil of amide III was also noted 29 .…”

“…Figure 3 shows Raman spectra of silk fabric before and after functionalization with 3 and 10 g/m 2 of AgNWs (Figure 3a‐d). Unmodified silk fabric revealed typical assignments of amino acids composition and structure of B. mori silk fibroin 20,31 . The main bands centered at 1219 and 1658 cm −1 indicate the β‐sheets structure of amide III (CH 2 bending) and amide I (C=O stretching), respectively.…”

“…Non‐dyed silk woven fabric characterized by mass per unit area of 70 g/m 2 , the thickness of 0.2 mm, and linear mass of weft and warp yarns of 37 dtex, was obtained from Łukasiewicz‐Textile Research Institute resources. This fabric was carefully studied in our previous work in comparison to silk fibroin after extracting from raw cocoons (degumming process) indicating structure and chemical composition suitable for biological purposes 20 . AgNWs were synthesized by the polyol process described in detail in our previous study 21 .…”

“…This fabric was carefully studied in our previous work in comparison to silk fibroin after extracting from raw cocoons (degumming process) indicating structure and chemical composition suitable for biological purposes. 20 AgNWs were synthesized by the polyol process described in detail in our previous study. 21 In brief, 0.408 g of AgNO 3 was diluted (Sigma-Aldrich, purity 99.9999%) in 20 ml of ethylene glycol (EG, POCH) and added (feed rate of 16 ml/h) to the mixture of 40 ml of EG, 2 g of polyvinyl pyrrolidone (PVP, Sigma Aldrich, molecular weight of 55 kDa) and 0.028 g of sodium chloride (NaCl, Chempur) and constantly heated to 170 C, refluxed and stirred at 570 rpm.…”

Silk Fibroin-g-Polyaniline Platform for the Design of Biocompatible-Electroactive Substrate

“…This stage is allocated to fragmented Fib chains produced by the degumming process [ 30 ]. The second step occurs at 530 °C, attributed to the Fib chain with a high molecular weight [ 31 ].…”