1,592 results match your criteria tunable lower


Imidazolium-fulleride ionic liquids - a DFT prediction.

Phys Chem Chem Phys 2021 Sep 13. Epub 2021 Sep 13.

Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, Kerala, 695 019, India.

Ionic liquids (ILs) exhibit tunable physicochemical properties due to the flexibility of being able to select their cation-anion combination from a large pool of ions. The size of the ions controls the properties of the ILs in the range from ionic to molecular, and thus large ions play an important role in regulating the melting temperature and viscosity. Here, we show that the exohedral addition of anionic X moieties to C (X = H, F, OH, CN, NH, and NO) is a thermodynamically viable process for creating large X-fulleride anions (CX). Read More

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September 2021

Silk-Cellulose Acetate Biocomposite Materials Regenerated from Ionic Liquid.

Polymers (Basel) 2021 Aug 29;13(17). Epub 2021 Aug 29.

Department of Physics and Astronomy, Rowan University, Glassboro, NJ 08028, USA.

The novel use of ionic liquid as a solvent for biodegradable and natural organic biomaterials has increasingly sparked interest in the biomedical field. As compared to more volatile traditional solvents that rapidly degrade the protein molecular weight, the capability of polysaccharides and proteins to dissolve seamlessly in ionic liquid and form fine and tunable biomaterials after regeneration is the key interest of this study. Here, a blended system consisting of silk fibroin protein and a cellulose derivative, cellulose acetate (CA), in the ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIMAc) was regenerated and underwent characterization to understand the structure and physical properties of the films. Read More

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One-step synthesis of nitrogen-doped multi-emission carbon dots and their fluorescent sensing in HClO and cellular imaging.

Mikrochim Acta 2021 Sep 8;188(10):330. Epub 2021 Sep 8.

College of Chemistry, Beijing Normal University, Beijing, 100875, China.

Tunable multicolor carbon dots (CDs) with a quantum yield reach up to 35% were generated directly from rhodamine and urea via one-step hydrothermal approach and purified through silica gel column chromatography. Transmission electron microscopy images reveal that the as-prepared CDs possess a small size distribution below 10 nm with bright blue, green, and yellow color emission, designated as b-CDs, g-CDs, and y-CDs, respectively. The in-depth investigations reveal that the multicolor emission CDs with different fraction displays fluorescence emission wavelength ranges from 398 nm (b-CDs), 525 nm (g-CDs), to 553 nm (y-CDs) which could be well modulated by controlling the amount of heteroatom nitrogen especially amino nitrogen onto their surface structures. Read More

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September 2021

Highly fluorescent g-CN nanobelts derived from bulk g-CN for NO gas sensing.

J Hazard Mater 2021 08 24;416:126195. Epub 2021 May 24.

Ministry of Education Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, and College of Chemistry, Fuzhou University, Fuzhou 350116, China. Electronic address:

The fluorescent emission wavelengths of nanostructures derived from bulk graphitic carbon nitride were commonly lower than those of their bulk due to the quantum confinement effect, which are disadvantageous for bioimaging and sensing applications. Herein, a new strategy to engineer graphitic carbon nitride nanomaterials with tunable fluorescent wavelength and intensity was proposed via thermal treatment of bulk graphitic carbon nitride at high temperature and then hydrolysis in alkali solution. Highly fluorescent g-CN nanobelts with emission peak at 494 nm, 19 nm higher than that of bulk graphitic carbon nitride and 23. Read More

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Organic Matrix Assisted Low-temperature Crystallization of Black Phase Inorganic Perovskites.

Angew Chem Int Ed Engl 2021 Sep 7. Epub 2021 Sep 7.

Shanghai Jiao Tong University, Environmental Science and Engineering, 800 Dongchuan Road, 44106, Shanghai, CHINA.

All-inorganic perovskites with comparable optoelectronic properties but improved intrinsic stability to organic-inorganic hybrid perovskites have attracted increasing amount of attention over years for applicational advances in perovskite solar cells (PSCs) and various optoelectronics including light-emitting devices (LEDs). Cesium lead halide perovskites of tunable I/Br ratio that possess bandgap aligning with the sunlight region are promising candidates for PSC. As impressive progress has been made on fabrication methods with device efficiency improved from the initial 2. Read More

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September 2021

Structural and Electrochemical Properties of Type VIII BaGaSn Clathrate (δ ≈ 1) during Lithiation.

ACS Appl Mater Interfaces 2021 Sep 3;13(36):42564-42578. Epub 2021 Sep 3.

Materials Science and Engineering, School for Engineering of Matter, Transport and Energy, Arizona State University, P.O. Box 876106, Tempe, Arizona 85827, United States.

Clathrates of the tetrel (Tt = Si, Ge, Sn) elements are host-guest structures that can undergo Li alloying reactions with high capacities. However, little is known about how the cage structure affects the phase transformations that take place during lithiation. To further this understanding, the structural changes of the type VIII clathrate BaGaSn (δ ≈ 1) during lithiation are investigated and compared to those in β-Sn with X-ray total scattering measurements and pair distribution function (PDF) analysis. Read More

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September 2021

Perovskite Quantum Dots Encapsulated in a Mesoporous Metal-Organic Framework as Synergistic Photocathode Materials.

J Am Chem Soc 2021 Sep 30;143(35):14253-14260. Epub 2021 Aug 30.

State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, P.R. China.

Metal halide perovskite quantum dots, with high light-absorption coefficients and tunable electronic properties, have been widely studied as optoelectronic materials, but their applications in photocatalysis are hindered by their insufficient stability because of the oxidation and agglomeration under light, heat, and atmospheric conditions. To address this challenge, herein, we encapsulated CsPbBr nanocrystals into a stable iron-based metal-organic framework (MOF) with mesoporous cages (∼5.5 and 4. Read More

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September 2021

Engineering of Electron Affinity and Interfacial Charge Transfer of Graphene for Self-Powered Nonenzymatic Biosensor Applications.

ACS Appl Mater Interfaces 2021 Sep 23;13(34):40731-40741. Epub 2021 Aug 23.

Department of Chemistry and Biochemistry, The University of Texas at El Paso, 500 W. University Avenue, El Paso, Texas 79968, United States.

Facile electron transport and intimate electronic contact at the catalyst-electrode interface are critical for the ideal performance of electrochemical devices such as glucose biofuel cells and biosensors. Here, through a comprehensive experimental-theoretical exploration, we demonstrate that engineering of interfacial properties, including interfacial electron dynamics, electron affinity, electrode-catalyst-adsorbate electrical synergy, and electrocatalytically active surface area, can lead to highly efficient graphene-based electrochemical devices. We selected two closely related but electronically and surface chemically different functionalized graphene analogues-graphene acid (GA) and reduced graphene oxide (rGO)-as the model graphenic platforms. Read More

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September 2021

Biomaterial nanocarrier-driven mechanisms to modulate anti-tumor immunity.

Curr Opin Biomed Eng 2021 Dec 30;20. Epub 2021 Jul 30.

Departments of Chemical and Biological Engineering, Iowa State University, Ames, IA.

Cancer immunotherapy approaches that utilize or enhance patients' inherent immunity have received extensive attention in the past decade. Biomaterial-based nanocarriers with tunable physicochemical properties offer significant promise in cancer immunotherapies. They can lower payload toxicity, provide sustained release of diverse payloads, and target specific disease site(s). Read More

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December 2021

Altering the Multimodal Resonance in Ultrathin Silicon Ring for Tunable THz Biosensing.

IEEE Trans Nanobioscience 2021 Aug 19;PP. Epub 2021 Aug 19.

A technique is implemented for altering the multimodal resonance generated in an ultrathin silicon ring resonator-based terahertz (THz) absorber. The absorber provides the dual-band resonance with the excitation of magnetic and electric dipole in the lower and upper band, respectively. The field of magnetic and electric dipoles is altered using a non-resonant graphene ring placed in the center of the generated dipolar arrangement and the tunability and perfect absorption is achieved. Read More

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Ferroelectricity and Ferromagnetism Achieved via Adjusting Dimensionality in BiFeO/BiMnO Superlattices.

ACS Appl Mater Interfaces 2021 Sep 19;13(34):41315-41322. Epub 2021 Aug 19.

Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China.

Integrating characteristics of materials through constructing artificial superlattices (SLs) has raised extensive attention in multifunctional materials. Here, we report the synthesis of BiFeO/BiMnO SLs with considerable ferroelectric polarizations and tunable magnetic moments. The polarization of BiFeO/BiMnO SLs presents a decent value of 12 μC/cm, even as the dimensionality of BiFeO layers per period is reduced to about five-unit cells when keeping the BiMnO layers same. Read More

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September 2021

Photoreactive hydrogel stiffness influences volumetric muscle loss repair.

Tissue Eng Part A 2021 Aug 19. Epub 2021 Aug 19.

University of Virginia, 2358, Chemical Engineering, Biomedical Engineering, Charlottesville, Virginia, United States;

Volumetric muscle loss (VML) injuries are characterized by permanent loss of muscle mass, structure, and function. Hydrogel biomaterials provide an attractive platform for skeletal muscle tissue engineering due to the ability to easily modulate their biophysical and biochemical properties to match a range of tissue characteristics. In this work we successfully developed a mechanically tunable hyaluronic acid (HA) hydrogel system to investigate the influence of hydrogel stiffness on VML repair. Read More

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Tandem Electrocatalytic CO Reduction with Efficient Intermediate Conversion over Pyramid-Textured Cu-Ag Catalysts.

ACS Appl Mater Interfaces 2021 Sep 18;13(34):40513-40521. Epub 2021 Aug 18.

International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.

If combined with renewably generated electricity, electrochemical CO reduction (E-COR) could be used as a sustainable source of chemicals and fuels. Tandem catalysis approaches are attractive for providing the product selectivity, which would be required for commercial applications. Here, we demonstrate a two-step tandem electrocatalytic E-COR with efficient conversion of the intermediate species. Read More

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September 2021

Tyrosol-Derived Biodegradable Inks with Tunable Properties for 3D Printing.

ACS Biomater Sci Eng 2021 09 16;7(9):4454-4462. Epub 2021 Aug 16.

Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States.

Three-dimensional (3D) printing has emerged as a valuable tool in medicine over the past few decades. With a growing number of applications using this advanced processing technique, new polymer libraries with varied properties are required. Herein, we investigate tyrosol-based poly(ester-arylate)s as biodegradable inks in fused deposition modeling (FDM). Read More

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September 2021

Photodissociation and Infrared Spectroscopy of Uranium-Nitrogen Cation Complexes.

J Phys Chem A 2021 Aug 13;125(33):7278-7288. Epub 2021 Aug 13.

Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States.

Laser vaporization of uranium in a pulsed supersonic expansion of nitrogen is used to produce complexes of the form U(N) ( = 1-8). These ions are mass selected in a reflectron time-of-flight spectrometer and studied with visible and UV laser fixed-frequency photodissociation and with tunable infrared laser photodissociation spectroscopy. The dissociation patterns and spectroscopy of U(N) indicate that N ligands are intact molecules and that there is no insertion chemistry resulting in UN or NUN. Read More

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Stimuli-responsive nanocarriers for bacterial biofilm treatme.

Rare Metals 2021 Aug 4:1-17. Epub 2021 Aug 4.

State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese of Academy, Changchun, 130022 China.

Abstract: Bacterial biofilm infections have been threatening the human's life and health globally for a long time because they typically cause chronic and persistent infections. Traditional antibiotic therapies can hardly eradicate biofilms in many cases, as biofilms always form a robust fortress for pathogens inside, inhibiting the penetration of drugs. To address the issues, many novel drug carriers emerged as promising strategies for biofilm treatment. Read More

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A Zwitterionic Polyurethane Nanoporous Device with Low Foreign-Body Response for Islet Encapsulation.

Adv Mater 2021 Aug 6:e2102852. Epub 2021 Aug 6.

Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA.

Encapsulation of insulin-producing cells is a promising strategy for treatment of type 1 diabetes. However, engineering an encapsulation device that is both safe (i.e. Read More

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Tunable Transmissive Terahertz Linear Polarizer for Arbitrary Linear Incidence Based on Low-Dimensional Metamaterials.

Nanomaterials (Basel) 2021 Jul 18;11(7). Epub 2021 Jul 18.

Shanghai Key Lab of Modern Optical System, Terahertz Spectrum and Imaging Technology Cooperative Innovation Center, Terahertz Technology Innovation Research Institute, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai 200093, China.

In this work, we propose a structure consisting of three metamaterial layers and a metallic grating layer to rotate the polarization of arbitrary linearly polarized incidence to the y-direction with high transmissivity by electrically tuning these metamaterials. The transfer matrix method together with a harmonic oscillator model is adopted to theoretically study the proposed structure. Numerical simulation based on the finite difference time-domain method is performed assuming that the metamaterial layers are constituted by graphene ribbon arrays. Read More

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Realization of an Ideal Cairo Tessellation in Nickel Diazenide NiN: High-Pressure Route to Pentagonal 2D Materials.

ACS Nano 2021 Aug 6. Epub 2021 Aug 6.

The Earth and Planets Laboratory, Carnegie Institution for Science, Washington, D.C. 20015, United States.

Most of the studied two-dimensional (2D) materials are based on highly symmetric hexagonal structural motifs. In contrast, lower-symmetry structures may have exciting anisotropic properties leading to various applications in nanoelectronics. In this work we report the synthesis of nickel diazenide NiN which possesses atomic-thick layers comprised of NiN pentagons forming Cairo-type tessellation. Read More

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Spectroscopy of NbSe Using Energy-Tunable Defect-Embedded Quantum Dots.

Nano Lett 2021 Aug 5;21(16):6931-6937. Epub 2021 Aug 5.

The Racah Institute of Physics, The Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem 91904, Israel.

Quantum dots have sharply defined energy levels, which can be used for high resolution energy spectroscopy when integrated in tunneling circuitry. Here we report dot-assisted spectroscopy measurements of the superconductor NbSe, using a van der Waals device consisting of a vertical stack of graphene-MoS-NbSe. The MoS tunnel barriers host naturally occurring defects which function as quantum dots, allowing transport via resonant tunneling. Read More

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Hyaluronic Acid Hydrogel Microspheres for Slow Release Stem Cell Delivery.

ACS Biomater Sci Eng 2021 08 29;7(8):3754-3763. Epub 2021 Jul 29.

Likarda LLC, 10330 Hickman Mills Drive, Suite B, Kansas City, Missouri 64137, United States.

Cell therapies are hampered by a lack of available delivery systems, resulting in inconsistent outcomes in animal studies and human clinical trials. Hydrogel encapsulants offer a broad range of tunable characteristics in the design of cell delivery vehicles. The focus of the hydrogel field has been on durable encapsulants that provide long-term paracrine function of the cells. Read More

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Electrochemical Potential-Driven High-Throughput Molecular Electronic and Spintronic Devices: From Molecules to Applications.

Angew Chem Int Ed Engl 2021 Jul 27. Epub 2021 Jul 27.

Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh, 208016, India.

Molecules are fascinating candidates for constructing tunable and electrically conducting devices by the assembly of either a single molecule or an ensemble of molecules between two electrical contacts followed by current-voltage (I-V) analysis, which is often termed "molecular electronics". Recently, there has been also an upsurge of interest in spin-based electronics or spintronics across the molecules, which offer additional scope to create ultrafast responsive devices with less power consumption and lower heat generation using the intrinsic spin property rather than electronic charge. Researchers have been exploring this idea of utilizing organic molecules, organometallics, coordination complexes, polymers, and biomolecules (proteins, enzymes, oligopeptides, DNA) in integrating molecular electronics and spintronics devices. Read More

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Influence of the Molecular Structure of Constituents and Liquid Phase Non-Ideality on the Viscosity of Deep Eutectic Solvents.

Molecules 2021 Jul 11;26(14). Epub 2021 Jul 11.

Biothermodynamics, TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany.

Hydrophobic deep eutectic solvents (DES) have recently been used as green alternatives to conventional solvents in several applications. In addition to their tunable melting temperature, the viscosity of DES can be optimized by selecting the constituents and molar ratio. This study examined the viscosity of 14 eutectic systems formed by natural substances over a wide range of temperatures and compositions. Read More

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Topical cationic hairy particles targeting cell free DNA in dermis enhance treatment of psoriasis.

Biomaterials 2021 09 15;276:121027. Epub 2021 Jul 15.

School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, GD Research Center for Functional Biomaterials Engineering and Technology, Sun Yat-sen University, 510275, Guangzhou, China. Electronic address:

Abnormal high level of cell free DNA (cfDNA) triggers chronic inflammation to exacerbate psoriasis symptoms. Scavenging cfDNA by topical cationic polymeric nanoparticles has been certified as an effective therapeutic strategy for treating psoriasis. However, cationic cfDNA scavengers have a great potential risk to organs after entering systemic circulation through skin barrier. Read More

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September 2021

Molecular Insight into Bubble Nucleation on the Surface with Wettability Transition at Controlled Temperatures.

Langmuir 2021 Jul 14;37(29):8765-8775. Epub 2021 Jul 14.

Key Laboratory of Power Station Energy Transfer Conversion and System (North China Electric Power University), Ministry of Education, Beijing 102206, China.

A surface with a smart wettability transition has recently been proposed to enhance the boiling heat transfer in either macro- or microscale systems. This work explores the mechanisms of bubble nucleation on surfaces with wettability transitions at controlled temperatures by molecular simulations. The results of the interaction energy at the interface and potential energy distribution of water molecules show that the nanostructure promotes nucleation over the copper surface and causes lower absolute potential energy to provide fixed nucleation sites for the initial generation of the bubble nucleus and shortens the incipient nucleation time, as compared to the mixed-wettability or hydrophilic nanostructure surface. Read More

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Investigation of thiolysis of 4-substituted SBD derivatives and rational design of a GSH-selective fluorescent probe.

Org Biomol Chem 2021 Jul;19(29):6527-6533

State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, National Pesticide Engineering Research Center, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin, 300071, China.

In order to evaluate 7-sulfonamide benzoxadiazole (SBD) derivatives for the development of fluorescent probes, herein we investigated the thiolysis reactivity and selectivity of a series of SBD compounds with different atoms (N/O/S/Se) at the 4-position. Both SBD-amine and SBD-ether are stable toward biothiols in buffer (pH 7.4), while SBD-selenoether can react efficiently with biothiols GSH/Hcy, Cys, and H2S to produce SBD-SG/S-Hcy, SBD-NH-Cys, and SBD-SH, respectively, with three different sets of spectral signals. Read More

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Incorporating nanocrystalline cellulose into a multifunctional hydrogel for heart valve tissue engineering applications.

J Biomed Mater Res A 2021 Jul 13. Epub 2021 Jul 13.

Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York, USA.

Functional tissue engineered heart valves (TEHV) have been an elusive goal for nearly 30 years. Among the persistent challenges are the requirements for engineered valve leaflets that possess nonlinear elastic tissue biomechanical properties, support quiescent fibroblast phenotype, and resist osteogenic differentiation. Nanocellulose is an attractive tunable biological material that has not been employed to this application. Read More

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Atomic Rearrangement and Amorphization Induced by Carbon Dioxide in Two-Dimensional MoO Nanomaterials.

J Phys Chem Lett 2021 Jul 9;12(28):6543-6550. Epub 2021 Jul 9.

College of Materials Science & Engineering, Zhengzhou University, Zhengzhou 450052, P.R. China.

Supercritical carbon dioxide (SC CO) has shown great potential in fabrication of two-dimensional (2D) amorphous nanomaterials with excellent electric and optical properties, while the amorphization mechanism led by SC CO is still unclear. In this work, by investigating the amorphization kinetics of MoO nanomaterials in SC CO, we find two amorphization mechanisms dependent on the SC CO pressure. At lower pressure, forming oxygen vacancies is the dominant effect, while at higher pressure, atomic rearrangement is the controlling factor. Read More

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Tunable Cytotoxicity and Selectivity of Phosphonium Ionic Liquid with Aniline Blue Dye.

J Nanosci Nanotechnol 2021 12;21(12):6143-6150

Department of Chemistry, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204, USA.

Ionic liquids are an interesting class of materials that have recently been utilized as chemotherapeutic agents in cancer therapy. Aniline blue, a commonly used biological staining agent, was used as a counter ion to trihexyltetradecylphosphonium, a known cytotoxic cation. A facile, single step ion exchange reaction was performed to synthesize a fluorescent ionic liquid, trihexyltetradecylphosphonium aniline blue. Read More

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December 2021

A novel and selective silk fibroin fragmentation method.

Soft Matter 2021 Jul;17(28):6863-6872

Department of Industrial Engineering, University of Trento, via Sommarive 9, Trento, Italy. and BIOTech Research Center, European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento, via delle Regole 101, Trento, Italy.

In the tissue-engineering field silk fibroin can be tailored to the target applications by modifying its secondary structure and molecular weight, and functionalizing the molecule with specific active groups linked to the amino acid side chains. To better tune the silk fibroin molecular weight and structural properties, we propose the creation of a lower molecular weight fibroin-derived material through a selective and tunable enzymatic attack on the fibroin chain. Cleavage at specific amino acid sites leads to precise silk fibroin fragmentation and, thus, lower molecular weight materials whose length and properties can be tuned with the enzyme concentration. Read More

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