Bioengineered Silk Protein-Based 3D In Vitro Models for Tissue Engineering and Drug Development: From Silk Matrix Properties to Biomedical Applications.

3D in vitro model has emerged as a valuable tool for studying tissue development, drug screening, and disease modeling. 3D systems can accurately replicate tissue microstructures and physiological features, mirroring the in vivo microenvironment departing from conventional 2D cell cultures. Various 3D in vitro models utilizing biomacromolecules like collagen and synthetic polymers have been developed to meet diverse research needs and address the complex challenges of contemporary research.

Aptamer-free upconversion nanoparticle/silk biosensor system for low-cost and highly sensitive detection of antibiotic residues.

The detection of antibiotics is crucial for safeguarding the environment, ensuring food safety, and promoting human health. However, developing a rapid, convenient, low-cost, and sensitive method for antibiotic detection presents significant challenges. Herein, an aptamer-free biosensor was successfully constructed using upconversion nanoparticles (UCNPs) coated with silk fibroin (SF), based on Förster resonance energy transfer (FRET) and the charge-transfer effect, for detecting roxithromycin (RXM).

Design of () Silk Fibroin Microspheres for Developing Biosafe Sunscreen.

Sunscreens play a crucial role in protecting the skin from ultraviolet (UV) damage. However, present commercial sunscreens have a tendency to generate free radicals in the UV window, resulting in serious inflammatory responses and health problems. In this study, we demonstrate that silk fibroin microspheres (SFMPs) assembled from regenerated silk fibroin (SF) could scavenge free radicals while preventing UV irradiation and thus present a promising sunscreen.

Injectable Bombyx mori (B. mori) silk fibroin/MXene conductive hydrogel for electrically stimulating neural stem cells into neurons for treating brain damage.

Brain damage is a common tissue damage caused by trauma or diseases, which can be life-threatening. Stem cell implantation is an emerging strategy treating brain damage. The stem cell is commonly embedded in a matrix material for implantation, which protects stem cell and induces cell differentiation.

Regenerated silk fibroin coating stable liquid metal nanoparticles enhance photothermal antimicrobial activity of hydrogel for wound infection repair.

The integration of liquid metal (LM) and regenerated silk fibroin (RSF) hydrogel holds great potential for achieving effective antibacterial wound treatment through the LM photothermal effect. However, the challenge of LM's uncontrollable shape-deformability hinders its stable application. To address this, we propose a straightforward and environmentally-friendly ice-bath ultrasonic treatment method to fabricate stable RSF-coated eutectic gallium indium (EGaIn) nanoparticles (RSF@EGaIn NPs).

Green, Low-carbon Silk-based Materials in Water Treatment: Current State and Future Trends.

The improper and inadequate treatment of industrial, agricultural, and household wastewater exerts substantial pressure on the existing ecosystem and poses a serious threat to the health of both humans and animals. To address these issues, different types of materials have been employed to eradicate detrimental pollutants from wastewater and facilitate the reuse of water resources. Nevertheless, owing to the challenges associated with the degradation of these traditional materials post-use and their incompatibility with the environment, natural biopolymers have garnered considerable interest.

Ultrafast Bi-Directional Bending Moisture-Responsive Soft Actuators through Superfine Silk Rod Modified Bio-Mimicking Hierarchical Layered Structure.

Development of stimulus-responsive materials is crucial for novel soft actuators. Among these actuators, the moisture-responsive actuators are known for their accessibility, eco-friendliness, and robust regenerative attributes. A major challenge of moisture-responsive soft actuators (MRSAs) is achieving significant bending curvature within short response times.

Hierarchically patterned protein scaffolds with nano-fibrillar and micro-lamellar structures modulate neural stem cell homing and promote neuronal differentiation.

Biophysical factors are essential in cell survival and behaviors, but constructing a suitable 3D microenvironment for the recruitment of stem cells and exerting their physiological functions remain a daunting challenge. Here, we present a novel silk fibroin (SF)-based fabrication strategy to develop hierarchical microchannel scaffolds for biomimetic nerve microenvironments . We first modulated the formation of SF nanofibers (SFNFs) that mimic the nanostructures of the native extracellular matrix (ECM) by using graphene oxide (GO) nanosheets as templates.

Silk Protein-Mediated Biomineralization: From Bioinspired Strategies and Advanced Functions to Biomedical Applications.

Biomineralization refers to the process through which minerals nucleate in a structured manner to form specific crystal structures by the regulating of biomacromolecules. Biomineralization occurs in bones and teeth within the human body, where collagen acts as a template for the nucleation of hydroxyapatite (HA) crystals. Similar to collagen, silk proteins spun by silkworms can also serve as templates for the nucleation and growth of inorganic substances at interfaces.

Upconversion nanoparticle-based aptasensor for rapid and ultrasensitive detection of by low-speed centrifugation.

Opportunistic foodborne pathogens such as () can cause a wide variety of threats to public health. There is an urgent clinical need for a fast, simple, low-cost, and sensitive method. Here, we designed a fluorescence-based aptamer biosensor (aptasensor) for detection using core-shell structured upconversion nanoparticles (CS-UCNPs) as a beacon.

Graphene Oxide-Coated Patterned Silk Fibroin Films Promote Cell Adhesion and Induce Cardiomyogenic Differentiation of Human Mesenchymal Stem Cells.

Cardiac tissue engineering is a promising strategy for the treatment of myocardial damage. Mesenchymal stem cells (MSCs) are extensively used in tissue engineering. However, transformation of MSCs into cardiac myocytes is still a challenge.

Novel Biomaterial-Binding/Osteogenic Bi-Functional Peptide Binds to Silk Fibroin Membranes to Effectively Induce Osteogenesis and .

Peptides can introduce new functions to biomaterials but their immobilization usually relies on inefficient physical adsorption or tedious chemical conjugation. Using the silk fibroin (SF) membrane (SFm) as a model biomaterial, here, we demonstrate a universal strategy for discovering new peptides that can "stick" to a biomaterial to functionalize it. Specifically, two peptide motifs, one screened by phage display biopanning for binding to the biomaterial (i.

Efficient Tumor Immunotherapy through a Single Injection of Injectable Antigen/Adjuvant-Loaded Macroporous Silk Fibroin Microspheres.

Synthetic or natural materials have been used as vaccines in cancer immunotherapy. However, using them as vaccines necessitates multiple injections or surgical implantations. To tackle such daunting challenges, we develop an injectable macroporous () silk fibroin (SF) microsphere loaded with antigens and immune adjuvants to suppress established tumors with only a single injection.

Arginine induces protein self-assembly into nanofibers for triggering osteogenic differentiation of stem cells.

Although silk proteins are considered promising in building a scaffold for tissue engineering, one of the silk proteins, silk sericin (BS), has limited processability in producing nanofibrous scaffolds because its surface charge anisotropy promotes gelation instead. To overcome this daunting challenge, we developed a mild and simple procedure for assembling BS into nanofibers and nanofibrous scaffolds. Briefly, arginine was added to the aqueous BS solution to reduce the negative charge of BS, thereby inducing BS to self-assemble into nanofibers in the solution.

Mesoscale structure development reveals when a silkworm silk is spun.

Silk fibre mechanical properties are attributed to the development of a multi-scale hierarchical structure during spinning. By careful ex vivo processing of a B. mori silkworm silk solution we arrest the spinning process, freezing-in mesoscale structures corresponding to three distinctive structure development stages; gelation, fibrilization and the consolidation phase identified in this work, a process highlighted by the emergence and extinction of 'water pockets'.

Biomineralization Directed by Prenucleated Calcium and Phosphorus Nanoclusters Improving Mechanical Properties and Osteogenic Potential of Antheraea pernyi Silk Fibroin-Based Artificial Periosteum.

The use of biomacromolecules as templates to control the nucleation and growth of hydroxyapatite crystals to prepare bioactive materials is a valuable approach in bone tissue engineering. Here, an artificial periosteum is prepared by biomineralizing Antheraea pernyi fibroin (AF) membrane with prenucleated nanoclusters, which can promote the osteogenic differentiation of mesenchymal stem cells (MSCs) and induce the formation of bone matrix protein in vivo. To achieve this, a biologically inspired prenucleated calcium and phosphorus nanocluster mineralization system is designed to nucleate and generate hydroxyapatite crystals on the surface of the AF membrane.

Air-plasma treatment promotes bone-like nano-hydroxylapatite formation on protein films for enhanced in vivo osteogenesis.

Introducing hydroxylapatite (HAp) into biomolecular materials is a promising approach to improve their bone regenerative capability. Thus a facile method needs to be developed to achieve this goal. Here we show that a simple air-plasma treatment of silk fibroin (SF) films for 5 min induced the formation of bone-like plate-shaped nano-HAp (nHAp) on their surface and the resultant material efficiently enhanced in vivo osteogenesis.

Protein Nanofibril Assemblies Templated by Graphene Oxide Nanosheets Accelerate Early Cell Adhesion and Induce Osteogenic Differentiation of Human Mesenchymal Stem Cells.

Bombyx mori silk fibroin (SF) is a promising natural biocompatible protein. However, its interaction with graphene oxide (GO) has never been studied and the resultant SF/GO matrix has not been used to direct stem cell fate. Herein, we found out that mixing SF molecules and GO nanosheets in an aqueous solution can trigger the assembly of SF nanoparticles into oriented nanofibrils due to the guidance of GO nanosheets, forming SF/GO films with unique nanotopographies and improved modulus upon the removal of the solvent.

Ice-Templated Protein Nanoridges Induce Bone Tissue Formation.

Little is known about the role of biocompatible protein nanoridges in directing stem cell fate and tissue regeneration due to the difficulty in forming protein nanoridges. Here an ice-templating approach is proposed to produce semi-parallel pure silk protein nanoridges. The key to this approach is that water droplets formed in the protein films are frozen into ice crystals (removed later by sublimation), pushing the surrounding protein molecules to be assembled into nanoridges.

In situ protein-templated porous protein-hydroxylapatite nanocomposite microspheres for pH-dependent sustained anticancer drug release.

Silk sericin, a water-soluble glue-like protein, is extensively used as a biomaterial due to its biocompatibility, hydrophilicity, biodegradability, and adequate resource. In addition, hydroxyapatite-based drug carriers are functionally efficient for drug or gene delivery due to their biodegradability, biocompatibility and easy metabolism . Herein, for the first time, this study used sericin, from a wild silkworm called (), as a template to nucleate hydroxylapatite (HAp) nano-needles and form porous sericin-HAp nanocomposite microspheres as an anticancer drug carrier.

Characterization of Transgenic Silkworm Yielded Biomaterials with Calcium-Binding Activity.

Silk fibers have many inherent properties that are suitable for their use in biomaterials. In this study, the silk fibroin was genetically modified by including a Ca-binding sequence, [(AGSGAG)6ASEYDYDDDSDDDDEWD]2 from shell nacreous matrix protein. It can be produced as fibers by transgenic silkworm.

Ca-induced self-assembly of silk sericin into a nanofibrous network-like protein matrix for directing controlled nucleation of hydroxylapatite nano-needles.

Bone biomineralization is a well-regulated protein-mediated process where hydroxylapatite (HAP) crystals are nucleated with preferred orientation within self-assembled protein matrix. Mimicking this process is a promising approach to the production of bone-like protein/mineral nanocomposites for bone repair and regeneration. Towards the goal of fabricating such nanocomposites from sericin, a protein spun by () silkworm, and bone mineral HAP, for the first time we investigated the chemical mechanism underpinning the synergistic processes of the conformational change/self-assembly of sericin ( ) as well as the nucleation of HAP on the resultant self-assembled matrix.

Tuning molecular weights of Bombyx mori (B. mori) silk sericin to modify its assembly structures and materials formation.

Bombyx mori (B. mori) silk sericin is a protein with features desirable as a biomaterial, such as increased hydrophilicity and biodegradation, as well as resistance to oxidation, bacteria, and ultraviolet light. In contrast to other widely studied B.

Biomimetic nucleation of hydroxyapatite crystals mediated by Antheraea pernyi silk sericin promotes osteogenic differentiation of human bone marrow derived mesenchymal stem cells.

Biomacromolecules have been used as templates to grow hydroxyapatite crystals (HAps) by biomineralization to fabricate mineralized materials for potential application in bone tissue engineering. Silk sericin is a protein with features desirable as a biomaterial, such as increased hydrophilicity and biodegradation. Mineralization of the silk sericin from Antheraea pernyi (A.

Mineralization and biocompatibility of Antheraea pernyi (A. pernyi) silk sericin film for potential bone tissue engineering.

This study aimed to investigate the mineralization of Antheraea pernyi (A. pernyi) silk sericin. Mineralization of A.