Search Results (27)

Wearable pressure sensors have emerged as vital tools in personalized monitoring, promising transformative advances in patient care and diagnostics. Nevertheless, conventional devices frequently suffer from limited sensitivity, inadequate flexibility, and concerns regarding biocompatibility. Herein, we introduce silk fibroin, a naturally occurring protein extracted from silkworm cocoons, as a promising material platform for next-generation wearable sensors. Owing to its remarkable biocompatibility, mechanical robustness, and structural tunability, silk fibroin serves as an ideal substrate for constructing capacitive pressure sensors tailored to medical applications. We engineered silk-derived capacitive architecture and evaluated its performance in real-time human motion and physiological signal detection. The resulting sensor exhibits a high sensitivity of 18.68 kPa⁻¹ over a broad operational range of 0 to 2.4 kPa, enabling accurate tracking of subtle pressures associated with pulse, respiration, and joint articulation. Under extreme loading conditions, our silk fibroin sensor demonstrated superior stability and accuracy compared to a commercial resistive counterpart (FlexiForce™ A401). These findings establish silk fibroin as a versatile, practical candidate for wearable pressure sensing and pave the way for advanced biocompatible devices in healthcare monitoring. Full article

Neurotrophic factor 3 (NT-3), a potent neurotrophin, promotes neuronal survival and axonal regeneration while demonstrating a unique capacity to induce lineage-specific differentiation of pluripotent stem cells into functional neurons, underscoring its therapeutic potential in neural repair. Despite these advantages, the large-scale production of recombinant human NT-3 with preserved structure integrity and functional bioactivity remains a critical challenge. This study takes advantage of the silk gland bioreactor of silkworms for the recombinant expression of human NT-3 protein on a large scale. Our findings reveal that NT-3 was successfully expressed in the middle silk gland of silkworms and secreted into the silk fibers, achieving a yield of up to 0.5 mg of bioactive NT-3 per gram of cocoon weight. The engineered NT-3-functionalized silk material demonstrates no cytotoxicity and significantly enhanced the proliferation, migration, and differentiation of neural cells compared to natural silk protein. Importantly, this functionalized material also promotes neurite outgrowth in HT-22 cells. These results collectively underscore the high bioactivity of the recombinant human NT-3 protein produced in the silkworm silk gland. The ongoing fabrication of NT-3-incorporated silk-based materials holds considerable promise for advancing tissue engineering and nerve regeneration applications. Full article

Background/Objectives: Burn injuries present significant treatment challenges due to the intricate nature of the healing process. Bombyx mori L. (silkworm) derivatives, containing healing-promoting proteins such as sericin and fibroin, as well as the anti-inflammatory enzyme serrapeptase, have shown promise as potential healing agents. This study aimed to identify the optimal dosage of silkworm body and gland extracts for burn healing, compare the selected dose’s effectiveness with that of silkworm cocoons, and assess the combined healing effects of a cocoon dressing and a silkworm body extract gel. Methods: An experimental model was employed using hairless SKH-hr2 female mice subjected to standardized second-degree burns. The mice received treatments with various formulations of silkworm body and gland extracts, silkworm cocoons, and a combined application of a cocoon dressing and silkworm body extract gel. Results: The most effective treatments were the cocoon dressing and the combination of cocoon dressing with 60% body extract gel. By Day 20, complete healing (100%) was observed in the 20% and 60% body and gland extract groups, while the cocoon and 60% gland extract groups exhibited 60% healing, significantly higher than the control group (0% healing). Wound contraction analysis showed the greatest reduction in surface area from Day 3 to Day 17 in the cocoon and 60% body extract groups (p < 0.05). Histopathological assessments revealed that the combination group exhibited the least tissue damage (score: 7), compared to the control (score: 10–13). Conclusions: The study highlights the poorly examined therapeutic potential of silkworm body and gland extracts, demonstrating their efficacy in accelerating burn healing. The effects observed by the silkworm cocoon and body extract suggests a novel and promising approach for burn wound management, warranting further clinical exploration. Full article

Sericin, a natural macromolecular protein and the main component of silkworm cocoons, exhibits biocompatibility, excellent mechanical properties, and biodegradability. Previous research has confirmed that the sericin protein possesses anticancer properties. Gastric cancer (GC) poses a serious hazard to human health, with a low rate of early diagnosis and a poor prognosis. Investigating the safety and effectiveness of drugs for their used in treatment is imperative. In this study, we confirmed that Antherea pernyi sericin (APS) inhibited the proliferation, migration, and clonal formation of GC cells and caused apoptosis in the cells by regulating the expression of Bcl2 and Bax. Moreover, our data show that APS did not exhibit significant toxicity in normal gastric mucosal cells and mice. Furthermore, the results show that APS suppressed the proliferation of cisplatin-resistant GC cells and promoted cellular apoptosis; however, it had no synergistic effects with cisplatin. All the results indicated that APS exhibits antitumor activity against GC and is a prospective medicinal agent for the clinical treatment of GC, with minimal toxicity and adverse side effects. This research can provide a theoretical basis for sericin in the field of tumor treatment, especially for the application of natural macromolecular polypeptide drugs. Full article

Inorganic–organic hybrid biomaterials have recently attracted much attention because of their widespread use. Silkworm cocoon filaments resulting from sericulture as prospective nanobiomaterials need to be improved, and their properties need to be used for broader purposes. This study was aimed at investigating methods for siliconization of silkworm cocoon filaments and characterizing their cocoon filament properties in terms of their yarn quality, natural dyeing, and antibacterial properties. Three methods of hybridization processes were used in this experiment, namely, in situ natural dyeing of silk yarns while silk filaments were spined, feed engineering through spraying the mulberry leaves with natural dyes and silica–phosphate–M (M = Cu, Fe, or Al) nano pastes, and a combination of both methods. The resulting cocoon filaments were characterized by their siliconization of filament fibers by using FTIR, XRD, and SEM-EDS methods. The yarn tensile strength, color quality, color fastness properties affected by the siliconization of silk filament fibers, and antibacterial properties were also investigated. Results showed that the combination method produced better siliconization of silk fibers, and, consequently, the better siliconization of silk fibers produced better natural dyeing as well as antibacterial properties of their resulting silk yarns. Full article

The commercialization of sodium batteries faces many challenges, one of which is the lack of suitable high-quality separators. Herein, we presented a novel natural silkworm cocoon-derived separator (SCS) obtained from the cocoon inner membrane after a simple degumming process. A Na||Na symmetric cell assembled with this separator can be stably cycled for over 400 h under test conditions of 0.5 mA cm⁻²–0.5 mAh cm⁻². Moreover, the Na||SCS||Na₃V₂(PO₄)₃ full cell exhibits an initial capacity of 79.3 mAh g⁻¹ at 10 C and a capacity retention of 93.6% after 1000 cycles, which far exceeded the 57.5 mAh g⁻¹ and 42.1% of the full cell using a commercial glass fiber separator (GFS). The structural origin of this excellent electrochemical performance lies in the fact that cationic functional groups (such as amino groups) on silkworm proteins can de-solvate Na-ions by anchoring the ClO₄⁻ solvent sheath, thereby enhancing the transference number, transport kinetics and deposition/dissolution properties of Na-ions. In addition, the SCS has significantly better mechanical properties and thinness indexes than the commercial GFS, and, coupled with the advantages of being natural, cheap, non-polluting and degradable, it is expected to be used as a commercialized sodium battery separator material. Full article

Sericin derived from the white cocoon of Bombyx mori has been attracting more attention for its utilization in food, cosmetics, and biomedicine. The potential health benefits of natural carotenoids for humans have also been well-established. Some rare strains of Bombyx mori (B. mori) produce yellow–red cocoons, which endow a potential of natural carotenoid-containing sericin. We hypothesized that natural carotenoid-containing sericin from yellow–red cocoons would exhibit better properties compared with white cocoon sericin. To investigate the physicochemical attributes of natural carotenoid-containing sericin, we bred two silkworm strains from one common ancestor, namely XS7 and XS8, which exhibited different cocoon colors as a result of the inconsistent distribution of lutein and β-carotene. Compared with white cocoon sericin, the interaction between carotenoids and sericin molecules in carotenoid-containing sericin resulted in a unique fluorescence emission at 530, 564 nm. The incorporation of carotenoids enhanced the antibacterial effect, anti-cancer ability, cytocompatibility, and antioxidant of sericin, suggesting potential wide-ranging applications of natural carotenoid-containing sericin as a biomass material. We also found differences in fluorescence characteristics, antimicrobial effects, anti-cancer ability, and antioxidants between XS7 and XS8 sericin. Our work for the first time suggested a better application potential of natural carotenoid-containing sericin as a biomass material than frequently used white cocoon sericin. Full article

Sericin, a fascinating natural biomaterial derived from silkworms, has received increasing interest in recent years for its unique bioactivity and high compatibility. Silkworms can be divided into wild-type or silk fibroin-deficient mutants according to whether they synthesize and secrete silk fibroin. Silk fibroin-deficient mutant silkworms and their cocoons are convenient for us to obtain diverse and high-quality sericin, which has been applicated in various fields such as cell culture, tissue engineering, drug delivery, and cosmetics. Here, we present an overview of our silkworm varieties resources, especially silk fibroin-deficient mutant silkworms. We optimized various extraction methods of sericin and summarized the characteristics and advantages of sericin. Finally, we developed and discussed a series of sericin-based biomaterials for promising applications for a diverse set of needs. Full article

Silk is a natural composite fiber composed mainly of hydrophobic fibroin and hydrophilic sericin, produced by the silkworm Bombyx mori. In the textile industry, the cocoons of B. mori are processed into silk fabric, where the sericin is substantially removed and usually discarded in wastewater. This wastewater pollutes the environment and water sources. However, sericin has been recognized as a potential biomaterial due to its biocompatibility, immunocompatibility, biodegradability, anti-inflammatory, antibacterial, antioxidant and photoprotective properties. Moreover, sericin can produce hydrogels, films, sponges, foams, dressings, particles, fibers, etc., for various biomedical and pharmaceutical applications (e.g., tissue engineering, wound healing, drug delivery, cosmetics). Given the severe environmental pollution caused by the disposal of sericin and its beneficial properties, there has been growing interest in upcycling this biomaterial, which could have a strong and positive economic, social and environmental impact. Full article

B. mori silkworm natural silk is a fibrous biopolymer with a block copolymer design containing both hydrophobic and hydrophilic regions. Using ¹H NMR relaxation, this work studied B. mori natural silk fibres oriented at 0° and 90° to the static magnetic field B₀ to clarify how measured NMR parameters reflect the structure and anisotropic properties of hydrated silk fibres. The FTIR method was applied to monitor the changes in the silk I and β-sheet conformations. Unloaded B. mori silk fibres at different hydration levels (HL), the silk threads before and after tensile loading in water, and fibres after a stepped increase in temperature have been explored. NMR data discovered two components in T₁ and T₂ relaxations for both orientations of silk fibres (0° and 90°). For the slower T₂ component, the results showed an obvious anisotropic effect with higher relaxation times for the silk fibres oriented at 90° to B₀. The T₁ component (water protons, HL = 0.11) was sequentially decreased over a range of fibres: 0° oriented, randomly oriented, silk B. mori cocoon, 90° oriented. The degree of anisotropy in T₂ relaxation was decreasing with increasing HL. The T₂ in silk threads oriented at 0° and 90° also showed anisotropy in increased HL (to 0.42 g H₂O/g dry matter), at tensile loading, and at an increasing temperature towards 320 K. The changes in NMR parameters and different relaxation mechanisms affecting water molecular interactions and silk properties have been discussed. The findings provide new insights relating to the water anisotropy in hydrated Bombyx mori silk fibres at tensile loading and under a changing HL and temperature. Full article

White cocoon is developed and used as a natural fiber, and different silkworm strains have different cocoon colors. Natural-colored cocoons are preferred by people, however, the cocoon color mainly settles on sericin and it basically falls off after reeling. Currently, there are no varieties applied to production due to the formation mechanism of cocoon color is not clear. The formation of cocoon color involves multiple gene regulations. Previous studies have shown that the main genes regulating cocoon traits are the yellow blood (Y) gene, yellow blood inhibitor (I) gene, and yellow cocoon (C) gene. Among them, the products of the Y gene and C gene have been studied, but the I gene is still unclear. In this study, the midgut tissues of the yellow (NB) and the white (306) cocoon silkworm were analyzed by whole transcriptome sequencing. The results showed that there are 1639 DE-circRNAs, 70 DE-miRNAs, and 3225 DE-mRNAs, including 1785 up-regulated genes and 1440 down-regulated genes. GO and KEGG annotation results indicated that DE-mRNAs are mainly involved in intracellular transport, signal transduction, lipid transport, and metabolic processes. Two key genes, KWMTBOMO10339 and KWMTBOMO16553, were screened out according to the annotation results, which were involved in amino acid transport and ion exchange function, respectively. The interaction analysis between ncRNA and target genes showed that there were five miRNAs regulating these two genes. The qPCR analysis showed that the I gene was down-regulated, and the miRNA expression profiles were most up-regulated. Therefore, during the yellow and white cocoon formation, KWMTBOMO10339 and KWMTBOMO16553 may be regulated by miRNA, resulting in the non-expression of KWMTBOMO10339 and KWMTBOMO16553 in yellow cocoon silkworm, and the pigment molecules can enter hemolymph from the midgut to form yellow blood, then transport to the middle silk gland to finally form yellow cocoons. Full article

Ionic liquids (ILs) show a bright application prospect in the field of biomedicine and energy materials due to their unique recyclable, modifiability, structure of cation and anion adjustability, as well as excellent physical and chemical properties. Dissolving silk fibroin (SF), from different species silkworm cocoons, with ILs is considered an effective new way to obtain biomaterials with highly enhanced/tailored properties, which can significantly overcome the shortcomings of traditional preparation methods, such as the cumbersome, time-consuming and the organic toxicity caused by manufacture. In this paper, the basic structure and properties of SF and the preparation methods of traditional regenerated SF solution are first introduced. Then, the dissolving mechanism and main influencing factors of ILs for SF are expounded, and the fabrication methods, material structure and properties of SF blending with natural biological protein, inorganic matter, synthetic polymer, carbon nanotube and graphene oxide in the ILs solution system are introduced. Additionally, our work summarizes the biomedicine and tissue engineering applications of silk-based materials dissolved through various ILs. Finally, according to the deficiency of ILs for dissolving SF at a high melting point and expensive cost, their further study and future development trend are prospected. Full article

As a unique and important biopolymer composite, silkworm cocoons have evolved a wide range of different structures and combinations of physical and chemical properties to resist environmental damage and attacks from natural predators. A combination of characterization techniques including scanning electron microscopy, mechanical tests, and Fourier transform infrared spectroscopy were applied to investigate the morphologies, mechanical properties, and nanoscale organizations of Antheraea pernyi cocoons from two different source regions. Mechanical tests were carried out by using rectangular specimens cut from four directions 0° (width of the cocoons), ±45°, and 90° (the length of the cocoon), separately. The mechanical properties such as tensile strength, initial modulus, and maximum load of cocoon in four directions were measured. The structural analysis of silkworm cocoon shows that there is a slightly different combination of morphology and properties that have adapted to coping with diverse local environments. The results of the mechanical properties of silkworm cocoons show that the A. pernyi cocoon from north of China behaved stronger and tougher. Besides, there were slight differences among the results of mechanical properties for 0°, ±45°, and 90° directions of these cocoons. Our studies will help formulate bio-inspired design principles for new materials. Full article

The availability of natural substances able to fulfill the role of antioxidants in a physiologic environment is important for the development of therapies against diseases associated with excessive production of reactive oxygen species and ensuing oxidative stress. Antioxidant properties have been reported episodically for sericin, a proteinaceous constituent of the silk thread in the cocoons generated by the larvae of the Lepidoptera order. We investigated the sericin fractions isolated from the cocoons spun by the domesticated (Bombyx mori) silkworm. Three fractions were isolated and evaluated, including two peptidoid fractions, the crude sericin and the purified (dialyzed) sericin, and the non-peptidoid methanolic extract of the crude fraction. When subjected to Trolox equivalent antioxidant capacity (TEAC) assay, the extract showed much higher antioxidant capacity as compared to the crude or purified sericin fractions. The three fractions were also evaluated in cultures of murine retinal photoreceptor cells (661 W), a cell line that is highly susceptible to oxidants and is crucially involved in the retinopathies primarily caused by oxidative stress. The extract displayed a significant dose-dependent protective effect on the cultured cells exposed to hydrogen peroxide. In identical conditions, the crude sericin showed a certain level of antioxidative activity at a higher concentration, while the purified sericin did not show any activity. We concluded that the non-peptidoid components accompanying sericin were chiefly responsible for the previously reported antioxidant capacity associated with sericin fractions, a conclusion supported by the qualitative detection of flavonoids in the extract but not in the purified sericin fraction. Full article

Researchers around the world are developing technologies to minimize carbon dioxide emissions or carbon neutrality in various fields. In this study, the dry spinning of regenerated silk fibroin (RSF) was achieved as a proof of concept for a process using ionic liquids as dissolution aids and plasticizers in developing natural polymeric materials. A dry spinning equipment system combining a stainless-steel syringe and a brushless motor was built to generate fiber compacts from a dope of silk fibroin obtained by degumming silkworm silk cocoons and ionic liquid 1-hexyl-3-methyl-imidazolium chloride ([HMIM][Cl]) according to a general method. The maximum stress and maximum elongation of the RSF fibers were 159.9 MPa and 31.5%, respectively. RSF fibers containing ionic liquids have a homogeneous internal structure according to morphological investigations. Elemental analysis of fiber cross sections revealed the homogeneous distribution of nonvolatile ionic liquid [HMIM][Cl] in RSF fibers. Furthermore, the removal of ionic liquids from RSF fibers through impregnation washing with organic solvents was verified to enhance industrial applications. Tensile testing showed that the fiber strength could be maintained even after removing the ionic liquid. Thermogravimetric analysis results show that the organic solvent 1,1,1,3,3,3-hexafluoro-2-propanol is chemically coordinated to silk fibroin and, as a natural polymer, can withstand heat up to 250 °C. Full article