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

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.

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Fractionation of Regenerated Silk Fibroin and Characterization of the Fractions

Molecules ◽

10.3390/molecules26206317 ◽

2021 ◽

Vol 26 (20) ◽

pp. 6317

Author(s):

Masaaki Aoki ◽

Yu Masuda ◽

Kota Ishikawa ◽

Yasushi Tamada

Keyword(s):

Mechanical Properties ◽

Secondary Structure ◽

Silk Fibroin ◽

Gel Permeation Chromatography ◽

Precipitation Process ◽

Regenerated Silk Fibroin ◽

Sds Page ◽

Fractionation Method ◽

Nonwoven Mats

The molecular weight (MW) of regenerated silk fibroin (RSF) decreases during degumming and dissolving processes. Although MW and the MW distribution generally affect polymer material processability and properties, few reports have described studies examining the influences of MW and the distribution on silk fibroin (SF) material. To prepare different MW SF fractions, the appropriate conditions for fractionation of RSF by ammonium sulfate (AS) precipitation process were investigated. The MW and the distribution of each fraction were found using gel permeation chromatography (GPC) and SDS-polyacrylamide electrophoresis (SDS-PAGE). After films of the fractionated SFs formed, the secondary structure, surface properties, and cell proliferation of films were evaluated. Nanofiber nonwoven mats and 3D porous sponges were fabricated using the fractionated SF aqueous solution. Then, their structures and mechanical properties were analyzed. The results showed AS precipitation using a dialysis membrane at low temperature to be a suitable fractionation method for RSF. Moreover, MW affects the nanofiber and sponge morphology and mechanical properties, although no influence of MW was observed on the secondary structure or crystallinity of the fabricated materials.

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Disruption of the Metal Ion Environment by EDTA for Silk Formation Affects the Mechanical Properties of Silkworm Silk

International Journal of Molecular Sciences ◽

10.3390/ijms20123026 ◽

2019 ◽

Vol 20 (12) ◽

pp. 3026 ◽

Cited By ~ 2

Author(s):

Qingsong Liu ◽

Xin Wang ◽

Xiaoyin Tan ◽

Xiaoqian Xie ◽

Haonan Dong ◽

...

Keyword(s):

Mechanical Properties ◽

Secondary Structure ◽

Metal Ions ◽

Silk Fibroin ◽

Metal Ion ◽

Conformational Transition ◽

Direct Injection ◽

Silk Gland ◽

Silk Fiber ◽

Edta Treatment

Silk fiber has become a research focus because of its comprehensive mechanical properties. Metal ions can influence the conformational transition of silk fibroin. Current research is mainly focused on the role of a single ion, rather than the whole metal ion environment. Here, we report the effects of the overall metal ion environment on the secondary structure and mechanical properties of silk fibers after direct injection and feeding of silkworms with EDTA. The metal composition of the hemolymph, silk gland, and silk fiber changed significantly post EDTA treatment. Synchrotron FTIR analysis indicated that the secondary structure of silk fiber after EDTA treatment changed dramatically; particularly, the β-sheets decreased and the β-turns increased. Post EDTA treatment, the silk fiber had significantly decreased strength, Young’s modulus, and toughness as compared with the control groups, while the strain exhibited no obvious change. These changes can be attributed to the change in the metal ion environment in the silk fibroin and sericin in the silk gland. Our investigation provides a new theoretical basis for the natural silk spinning process, and our findings could help develop a method to modify the mechanical properties of silk fiber using metal ions.

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Anti-Inflammatory Properties of Injectable Betamethasone-Loaded Tyramine-Modified Gellan Gum/Silk Fibroin Hydrogels

Biomolecules ◽

10.3390/biom10101456 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1456

Author(s):

Isabel Matos Oliveira ◽

Cristiana Gonçalves ◽

Myeong Eun Shin ◽

Sumi Lee ◽

Rui Luis Reis ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Mechanical Properties ◽

Silk Fibroin ◽

Therapeutic Efficacy ◽

Composite Structures ◽

Gelation Time ◽

Polymeric Materials ◽

Gellan Gum ◽

Traditional Use

Rheumatoid arthritis is a rheumatic disease for which a healing treatment does not presently exist. Silk fibroin has been extensively studied for use in drug delivery systems due to its uniqueness, versatility and strong clinical track record in medicine. However, in general, natural polymeric materials are not mechanically stable enough, and have high rates of biodegradation. Thus, synthetic materials such as gellan gum can be used to produce composite structures with biological signals to promote tissue-specific interactions while providing the desired mechanical properties. In this work, we aimed to produce hydrogels of tyramine-modified gellan gum with silk fibroin (Ty–GG/SF) via horseradish peroxidase (HRP), with encapsulated betamethasone, to improve the biocompatibility and mechanical properties, and further increase therapeutic efficacy to treat rheumatoid arthritis (RA). The Ty–GG/SF hydrogels presented a β-sheet secondary structure, with gelation time around 2–5 min, good resistance to enzymatic degradation, a suitable injectability profile, viscoelastic capacity with a significant solid component and a betamethasone-controlled release profile over time. In vitro studies showed that Ty–GG/SF hydrogels did not produce a deleterious effect on cellular metabolic activity, morphology or proliferation. Furthermore, Ty–GG/SF hydrogels with encapsulated betamethasone revealed greater therapeutic efficacy than the drug applied alone. Therefore, this strategy can provide an improvement in therapeutic efficacy when compared to the traditional use of drugs for the treatment of rheumatoid arthritis.

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Is Dialdehyde Chitosan a Good Substance to Modify Physicochemical Properties of Biopolymeric Materials?

International Journal of Molecular Sciences ◽

10.3390/ijms22073391 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3391

Author(s):

Sylwia Grabska-Zielińska ◽

Alina Sionkowska ◽

Ewa Olewnik-Kruszkowska ◽

Katarzyna Reczyńska ◽

Elżbieta Pamuła

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Physicochemical Properties ◽

Silk Fibroin ◽

Three Dimensional ◽

Microscopy Imaging ◽

Maximum Deformation ◽

One Step ◽

Chitosan Blends ◽

Fourier Transfer Infrared Spectroscopy

The aim of this work was to compare physicochemical properties of three dimensional scaffolds based on silk fibroin, collagen and chitosan blends, cross-linked with dialdehyde starch (DAS) and dialdehyde chitosan (DAC). DAS was commercially available, while DAC was obtained by one-step synthesis. Structure and physicochemical properties of the materials were characterized using Fourier transfer infrared spectroscopy with attenuated total reflectance device (FTIR-ATR), swelling behavior and water content measurements, porosity and density observations, scanning electron microscopy imaging (SEM), mechanical properties evaluation and thermogravimetric analysis. Metabolic activity with AlamarBlue assay and live/dead fluorescence staining were performed to evaluate the cytocompatibility of the obtained materials with MG-63 osteoblast-like cells. The results showed that the properties of the scaffolds based on silk fibroin, collagen and chitosan can be modified by chemical cross-linking with DAS and DAC. It was found that DAS and DAC have different influence on the properties of biopolymeric scaffolds. Materials cross-linked with DAS were characterized by higher swelling ability (~4000% for DAS cross-linked materials; ~2500% for DAC cross-linked materials), they had lower density (Coll/CTS/30SF scaffold cross-linked with DAS: 21.8 ± 2.4 g/cm3; cross-linked with DAC: 14.6 ± 0.7 g/cm3) and lower mechanical properties (maximum deformation for DAC cross-linked scaffolds was about 69%; for DAS cross-linked scaffolds it was in the range of 12.67 ± 1.51% and 19.83 ± 1.30%) in comparison to materials cross-linked with DAC. Additionally, scaffolds cross-linked with DAS exhibited higher biocompatibility than those cross-linked with DAC. However, the obtained results showed that both types of scaffolds can provide the support required in regenerative medicine and tissue engineering. The scaffolds presented in the present work can be potentially used in bone tissue engineering to facilitate healing of small bone defects.

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Nanostructure, Self-Assembly, Mechanical Properties, and Antioxidant Activity of a Lupin-Derived Peptide Hydrogel

Biomedicines ◽

10.3390/biomedicines9030294 ◽

2021 ◽

Vol 9 (3) ◽

pp. 294

Author(s):

Raffaele Pugliese ◽

Anna Arnoldi ◽

Carmen Lammi

Keyword(s):

Mechanical Properties ◽

Antioxidant Activity ◽

Self Assembly ◽

Antioxidant Activities ◽

Functional Materials ◽

Cd Spectroscopy ◽

Beneficial Effects ◽

Naturally Occurring ◽

New Research ◽

Peptide Hydrogel

Naturally occurring food peptides are frequently used in the life sciences due to their beneficial effects through their impact on specific biochemical pathways. Furthermore, they are often leveraged for applications in areas as diverse as bioengineering, medicine, agriculture, and even fashion. However, progress toward understanding their self-assembling properties as functional materials are often hindered by their long aromatic and charged residue-enriched sequences encrypted in the parent protein sequence. In this study, we elucidate the nanostructure and the hierarchical self-assembly propensity of a lupin-derived peptide which belongs to the α-conglutin (11S globulin, legumin-like protein), with a straightforward N-terminal biotinylated oligoglycine tag-based methodology for controlling the nanostructures, biomechanics, and biological features. Extensive characterization was performed via Circular Dichroism (CD) spectroscopy, Fourier Transform Infrared spectroscopy (FT-IR), rheological measurements, and Atomic Force Microscopy (AFM) analyses. By using the biotin tag, we obtained a thixotropic lupin-derived peptide hydrogel (named BT13) with tunable mechanical properties (from 2 to 11 kPa), without impairing its spontaneous formation of β-sheet secondary structures. Lastly, we demonstrated that this hydrogel has antioxidant activity. Altogether, our findings address multiple challenges associated with the development of naturally occurring food peptide-based hydrogels, offering a new tool to both fine tune the mechanical properties and tailor the antioxidant activities, providing new research directions across food chemistry, biochemistry, and bioengineering.

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Tunable Microstructures of Ultralong Organic Phosphorescence Materials

Chemical Communications ◽

10.1039/d1cc01563j ◽

2021 ◽

Author(s):

Kun Liu ◽

Kaiwei Huang ◽

Anqi Lv ◽

Wenpeng Ye ◽

Yijun Yang ◽

...

Keyword(s):

Self Assembly ◽

Solution Concentration ◽

Assembly Strategy ◽

Considerable Promise ◽

Organic Phosphor

Three kinds of microstructures of one organic phosphor were perpared based on a solution-concentration-controlled self-assembly strategy. These microstructures show different phosphorescence efficiency, which holds considerable promise for the miniaturized optical...

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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

RSC Advances ◽

10.1039/d1ra01300a ◽

2021 ◽

Vol 11 (29) ◽

pp. 17914-17923

Author(s):

Reza Eivazzadeh-Keihan ◽

Hooman Aghamirza Moghim Aliabadi ◽

Fateme Radinekiyan ◽

Mohammad Sobhani ◽

Farzane khalili ◽

...

Keyword(s):

Mechanical Properties ◽

Wound Healing ◽

Biological Activity ◽

Silk Fibroin ◽

Agarose Hydrogel ◽

Novel Scaffold ◽

Fibroin Solution ◽

Zinc Chromite

Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr2O4) nanoparticles.

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