Silk fabric protection obtained via chemical conjugation of transglutaminase and silk fibroin reinforcement

Abstract

Historic silk fabric is an important part of Chinese precious cultural heritage and its protection has always been a major challenge. This paper proposes a bio-safety method by the chemical conjugation of transglutaminase (TGase or TG) and sodium caseinate (SC), which produced a macromolecular polymer between protein molecules and enhanced silk fabrics. The changes of the mechanical properties of the reinforced silk fabric after washing by 10 cycles were not obvious, indicating good washing durability. After TGase and SC reinforcement, the silk fibroin (SF) solution was sprayed on the surface of silk fabric to improve the mechanical properties, where the secondary structure were formed by the self-assembly of SF to improve the mechanical properties. Therefore, the breaking stress attained the maximum value when the SF solution concentration was 1.0%. Meanwhile, the breaking stress increased by about 20.89% compared with untreated silk fabric. When the artificially alkali aged silk fabric is reinforced, the breaking stress and strain of the reinforced sample increased by 37.77% relative to the alkali aged fabric. The surface morphology and secondary structure transformation of the samples were also analyzed by scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. The results indicated that a significant SF layer was introduced on the surface of the silk fabric and the β-sheet structure increased due to the synergetic role of the macromolecular polymer and SF. Moreover, it is concluded that an increase in temperature and humidity will result in a decrease in the preservation index, which caused the degradation of silk fabric and proved that the preservation time of the reinforced silk fabric in the same environment was longer than that of the unreinforced sample. The biological enzyme chemical conjugation with silk fabric and physical combination of the pure SF solution is expected to be applied to the protection and enhancement of silk cultural relics.

Enzymatic Azido-GalNAc-Functionalized Silk Fibroin for Click Chemistry Conjugation

“…Enzyme catalyzed fibroin conjugations have been previously performed using mushroom tyrosine kinase (oxidation of tyrosine to O -quinone) and transglutaminase (glutamine-lysine cross-linking), demonstrating that, while not naturally occurring, silk fibroin can be used as a substrate for enzymes in vitro, allowing highly specific biochemical reactions to occur. O -GalNAc-transferases catalyze the transfer of N -acetylgalactosamine from UDP-GalNAc to the hydroxyls of serines/threonines of proteins to form O -linked glycans ( O -GalNAc) during post translational modification .…”

Develop an environment‐friendly detergent for textile relics adsorbing soil/rust stains

“…Moreover, given that textile relics are the precious national protected material heritage, they could not be used for experimental work, and therefore proxy materials (namely, simulated samples of textile relics) had to be made. Additionally, some scholars pointed out that the alkali-treated samples were quite close to the textile relics unearthed from Xiaohe cemetery more than 4000 years ago (Seon et al, 2017;Zhao, Pan, et al, 2019). Therefore, we chose the alkali-treatment as the preparation method of proxy materials (simulated samples of textile relics) for this study.…”

“…Additionally, textile relics are also indispensable parts of ancient Chinese civilization, owning with higher artistic, historical and scientific value (Liu et al, 2021;Liu, Wu, et al, 2022;Skoglund et al, 2020). However, textile relics belong to the relics eroded by the corpse, coffin fluid, microorganisms, bronzes, wood, soil and other stains due to being long-term buried in the ground (He et al, 2014;Zhao, Pan, et al, 2019).…”

Molecular Evidence of Structural Changes in Silk Using Unlimited Degradation Mass Spectrometry

“…The first use of silk to produce textiles was estimated to have occurred in the Yang Shao culture period more than 5000 years ago. Unfortunately, direct evidence of this is lacking due to physical and chemical factors – involving microorganisms, temperature, pH, force, and so on. Silk degradation made it very difficult to trace its existence, let alone its origin.…”