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1.
Nano Lett ; 24(25): 7724-7731, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864413

RESUMO

Perovskite monocrystalline films are regarded as desirable candidates for the integration of high-performance optoelectronics due to their unique photophysical properties. However, the heterogeneous integration of a perovskite monocrystalline film with other semiconductors is fundamentally limited by the lattice mismatch, which hinders direct epitaxy. Herein, the van der Waals (vdW) integration strategy for 3D perovskites is developed, where perovskite monocrystalline films are epitaxially grown on the mother substrate, followed by its peeling off and transferring to arbitrary semiconductors, forming monocrystalline heterojunctions. The as-achieved CsPbBr3-Nb-doped SrTiO3 (Nb:STO) vdW p-n heterojunction exhibited comparable performance to their directly epitaxial counterpart, demonstrating the feasibility of vdW integration for 3D perovskites. Furthermore, the vdW integration could be extended to silicon substrates, rendering the CsPbBr3-n-Si and CsPbCl3-p-Si p-n heterojunction with apparent rectification behaviors and photoresponse. The vdW integration significantly enriches the selections of semiconductors hybridizing with perovskites and provides opportunities for monocrystalline perovskite optoelectronics with complex configurations and multiple functionalities.

2.
Eur J Oral Sci ; 132(3): e12987, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38616404

RESUMO

Resin-based three-dimensional (3D) printing finds extensive application in the field of dentistry. Although studies of cytotoxicity, mechanical and physical properties have been conducted for newly released 3D printing resins such as Crowntec (Saremco), Temporary Crown Resin (Formlabs) and Crown & Bridge (Nextdent), the resistance of these materials to esterases in saliva has not been demonstrated at the molecular level. Therefore, in this study, the binding affinities and stability of these new 3D printing resins to the catalytic sites of esterases were investigated using molecular docking and molecular mechanics with Poisson-Bolzmann and surface area solvation (MM/PBSA) methods after active pocket screening. Toxicity predictions of the materials were also performed using ProTox-II and Toxtree servers. The materials were analyzed for mutagenicity, cytotoxicity, and carcinogenicity, and LD50 values were predicted from their molecular structures. The results indicated that out of the three novel 3D printing materials, Nexdent exhibited reduced binding affinity to esterases, indicating enhanced resistance to enzymatic degradation and possessing a superior toxicity profile.


Assuntos
Simulação de Acoplamento Molecular , Impressão Tridimensional , Humanos , Esterases/metabolismo , Esterases/química , Animais , Teste de Materiais , Materiais Dentários/química
3.
Small ; 16(10): e1906707, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32022431

RESUMO

Selective hydrogenation of nitriles is an industrially relevant synthetic route for the preparation of primary amines. Amorphous metal-boron alloys have a tunable, glass-like structure that generates a high concentration of unsaturated metal surface atoms that serve as active sites in hydrogenation reactions. Here, a method to create nanoparticles composed of mesoporous 3D networks of amorphous nickel-boron (Ni-B) alloy is reported. The hydrogenation of benzyl cyanide to ß-phenylethylamine is used as a model reaction to assess catalytic performance. The mesoporous Ni-B alloy spheres have a turnover frequency value of 11.6 h-1 , which outperforms non-porous Ni-B spheres with the same composition. The bottom-up synthesis of mesoporous transition metal-metalloid alloys expands the possible reactions that these metal architectures can perform while simultaneously incorporating more Earth-abundant catalysts.

4.
Biotechnol Bioeng ; 117(4): 912-923, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31885073

RESUMO

Rational embellishment of self-assembling two-dimensional (2D) proteins make it possible to build 3D nanomaterials with novel catalytic, optoelectronic and mechanical properties. However, introducing multiple sites of embellishment into 2D protein arrays without affecting the self-assembly is challenging, limiting the ability to program in additional functionality and new 3D configurations. Here we introduce two orthogonal covalent linkages at multiple sites in a 2D crystalline-forming protein without affecting its self-assembly. We first engineered the surface-layer protein SbsB from Geobacillus stearothermophilus pV72/p2 to display isopeptide bond-forming protein conjugation pairs, SpyTag or SnoopTag, at four positions spaced 5.7-10.5 nm apart laterally and 3 nm axially. The C-terminal and two newly-identified locations within SbsB monomer accommodated the short SpyTag or SnoopTag peptide tags without affecting the 2D lattice structure. Introducing tags at distinct locations enabled orthogonal and covalent binding of SpyCatcher- or SnoopCatcher-protein fusions to micron-sized 2D nanosheets. By introducing different types of bifunctional cross-linkers, the dual-functionalized nanosheets were programmed to self-assemble into different 3D stacks, all of which retain their nanoscale order. Thus, our work creates a modular protein platform that is easy to program to create dual-functionalized 2D and lamellar 3D nanomaterials with new catalytic, optoelectronic, and mechanical properties.


Assuntos
Nanoestruturas/química , Proteínas Recombinantes de Fusão , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Fenômenos Bioquímicos , Biotecnologia , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Nanotecnologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Propriedades de Superfície
5.
Small ; 10(15): 2992-9, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-24789084

RESUMO

Recent developments of 3D-graphene and 3D-boron-nitride have become of great interest owing to their potential for ultra-light flexible electronics. Here we demonstrate the first synthesis of novel 3D-BNC hybrids. By specifically controlling the compositions of C and BN, new fascinating properties are observed, such as highly tunable electrical conductivity, controllable EMI shielding properties, and stable thermal conductivity. This ultra-light hybrid opens up many new applications such as for electronic packaging and thermal interface materials (TIMs).

6.
Data Brief ; 54: 110331, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38550233

RESUMO

The quality of datasets is crucial in computer graphics and machine learning research and development. This paper presents the Render Lighting Dataset, featuring 63,648 rendered images of Blender's primitive shapes with various lighting conditions and engines. The images were created using Blender 4.0's Cycles and Eevee Render Engines, with careful attention to detail in texture mapping and UV unwrapping. The dataset covers six different lighting conditions, including Area Light, Spotlight, Point Light, Tri-Light, HDRI (Sunlight), and HDRI (Overcast), each adjusted using Blender's different options in the Color Management panel. With thirteen unique materials, ranging from Coastal Sand to Glossy Plastic, the dataset provides visual diversity for researchers to explore material properties under different lighting conditions using different render engines. This dataset serves as a valuable resource for researchers looking to enhance 3D rendering engines. Its diverse set of rendered images under varied lighting conditions and material properties allows researchers to benchmark and evaluate the performance of different rendering engines, develop new rendering algorithms and techniques, optimize rendering parameters, and understand rendering challenges. By enabling more realistic and efficient rendering, advancing research in lighting simulation, and facilitating the development of AI-driven rendering techniques, this dataset has the potential to shape the future of computer graphics and rendering technology.

7.
J Hazard Mater ; 448: 130804, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36724629

RESUMO

3D felt materials with pore structures have the advantages of high absorption performance and recyclability in oily wastewater treatment and chemical leakage. However, most of them were fabricated using either toxic organic solvents or complicated procedures. Herein, we report a facile, green, and scalable route for the fabrication of 3D composite felts with large pore structures by sequentially stirring and heating polyethylene terephthalate (PET) fibers and polyvinylidene fluoride (PVDF). The resulting PET-PVDF felt exhibits high oil absorption capacity to a variety of oil and organic solvents with a maximum saturated absorption capacity of 32 g/g. Additionally, it can be used to separate oil/water mixtures with a separation efficiency of 99.9% and separation flux of 89570 L m-2 h-1. Moreover, this felt shows excellent mechanical durability and chemical stability under acid, base, salt solution, and other harsh environments. The current study provides a promising approach for large-scale industrial oily wastewater separation.

8.
Bioresour Technol ; 381: 129144, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37172744

RESUMO

This study reports a biocatalytic system of immobilized laccase and 3D printed open-structure biopolymer scaffoldings. The scaffoldings were computer-designed and 3D printed using polylactide (PLA) filament. The immobilization of laccase onto the 3D printed PLA scaffolds were optimized with regard to pH, enzyme concentration, and immobilization time. Laccase immobilization resulted in a small reduction in reactivity (in terms of Michaelis constant and maximum reaction rate) but led to significant improvement in chemical and thermal stability. After 20 days of storage, the immobilized and free laccase showed 80% and 35% retention of the initial enzymatic activity, respectively. The immobilized laccase on 3D printed PLA scaffolds achieved 10% improvement in the removal of estrogens from real wastewater as compared to free laccase and showed the significant reusability potential. Results here are promising but also highlight the need for further study to improve enzymatic activity and reusability.


Assuntos
Enzimas Imobilizadas , Águas Residuárias , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Lacase/metabolismo , Poliésteres , Impressão Tridimensional , Concentração de Íons de Hidrogênio
9.
Biomater Adv ; 151: 213465, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37236118

RESUMO

Biocompatible three-dimensional porous scaffolds are widely used in multiple biomedical applications. However, the fabrication of tailor-made 3D structures with controlled and combined multiscale macroscopic-microscopic, surface and inner porosities in a straightforward manner is still a current challenge. Herein, we use multimaterial fused deposition modeling (FDM) to generate poly (vinyl alcohol) (PVA) sacrificial moulds filled with poly (Ɛ-caprolactone) (PCL) to generate well defined PCL 3D objects. Further on, the supercritical CO2 (SCCO2) technique, as well as the breath figures mechanism (BFs), were additionally employed to fabricate specific porous structures at the core and surfaces of the 3D PCL object, respectively. The biocompatibility of the resulting multiporous 3D structures was tested in vitro and in vivo, and the versatility of the approach was assessed by generating a vertebra model fully tunable at multiple pore size levels. In sum, the combinatorial strategy to generate porous scaffolds offers unique possibilities to fabricate intricate structures by combining the advantages of additive manufacturing (AM), which provides flexibility and versatility to generate large sized 3D structures, with advantages of the SCCO2 and BFs techniques, which allow to finely tune the macro and micro porosity at material surface and material core levels.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Porosidade , Álcool de Polivinil , Impressão Tridimensional
10.
Nanomaterials (Basel) ; 13(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37242050

RESUMO

Chiral plasmonic nanostructures have emerged as promising objects for numerous applications in nanophotonics, optoelectronics, biosensing, chemistry, and pharmacy. Here, we propose a novel method to induce strong chirality in achiral ensembles of gold nanoparticles via irradiation with circularly-polarized light of a picosecond Nd:YAG laser. Embedding of gold nanoparticles into a nanoporous silicate matrix leads to the formation of a racemic mixture of metal nanoparticles of different chirality that is enhanced by highly asymmetric dielectric environment of the nanoporous matrix. Then, illumination with intense circularly-polarized light selectively modifies the particles with the chirality defined by the handedness of the laser light, while their "enantiomers" survive the laser action almost unaffected. This novel modification of the spectral hole burning technique leads to the formation of an ensemble of plasmonic metal nanoparticles that demonstrates circular dichroism up to 100 mdeg. An unforeseen peculiarity of the chiral nanostructures obtained in this way is that 2D and 3D nanostructures contribute almost equally to the observed circular dichroism signals. Thus, the circular dichroism is neither even nor odd under reversal of direction of light propagation. These findings will help guide the development of a passive optical modulator and nanoplatform for enhanced chiral sensing and catalysis.

11.
Chem Asian J ; 17(16): e202200567, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35726484

RESUMO

Over the past few years, the environmentally friendly synthesis of nanomaterials, including graphene using green chemistry, has attracted tremendous attention due to its easy handling, low cost, and biocompatibility. Here we demonstrate a facile and efficient green synthesis route for producing highly stable and electrochemically active three-dimensional interconnected graphene frameworks (3DIGF) from jute sticks. Initially, jute sticks derived three-dimensional amorphous activated carbon nanosheets (3DAACNs) were prepared at low temperatures (i. e., 850 °C) in an inert environment. The resultant 3DAACNs were then heat treated at a high temperature (i. e., 2700 °C) under an inert environment, resulting in 3DIGF. The prepared carbonaceous materials were fully characterized, and various experimental techniques confirmed the preparation of 3DIGF. The prepared 3DIGF shows a highly stable nature in thermal and chemical environments and demonstrates a highly dynamic nature for the electrooxidation of sulfide. This study could be considered a vital contribution towards the economic and simple approach for preparing 3DIGF from biomass.


Assuntos
Grafite , Biomassa , Grafite/química
12.
Front Oncol ; 12: 975603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387077

RESUMO

Sternectomy is a procedure mainly used for removing tumor masses infiltrating the sternum or treating infections. Moreover, the removal of the sternum involves the additional challenge of performing a functional reconstruction. Fortunately, various approaches have been proposed for improving the operation and outcome of reconstruction, including allograft transplantation, using novel materials, and developing innovative surgical approaches, which promise to enhance the quality of life for the patient. This review will highlight the surgical approaches to sternum reconstruction and the new perspectives in the current literature.

13.
Adv Mater ; 32(18): e1903850, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31788850

RESUMO

Recent achievements and future opportunities for the design of 2D, 3D, and 4D materials using photochemical reactions are summarized. Light is an attractive stimulus for material design due to its outstanding spatiotemporal control, and its ability to mediate rapid polymerization under moderate reaction temperatures. These features have been significantly enhanced by major advances in light generation/manipulation with light-emitting diodes and optical fiber technologies which now allows for a broad range of cost-effective fabrication protocols. This combination is driving the preparation of sophisticated 2D, 3D, and 4D materials at the nano-, micro-, and macrosize scales. Looking ahead, future challenges and opportunities that will significantly impact the field and help shape the future of light as a versatile and tunable design tool are highlighted.

14.
Indian J Orthop ; 54(Suppl 2): 217-227, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33194095

RESUMO

INTRODUCTION: 3D printing has widespread applications in orthopaedics including creating biomodels, patient-specific instruments, implants, and developing bioprints. 3DGraphy or printing 3D models enable the surgeon to understand, plan, and simulate different procedures on it. Despite widespread applications in non-healthcare specialties, it has failed to gain traction in healthcare settings. This is perhaps due to perceived capital expenditure cost and the lack of knowledge and skill required to execute the process. PURPOSE: This article is written with an aim to provide step-by-step instructions for setting up a cost-efficient 3D printing laboratory in an institution or standalone radiology centre. The article with the help of video modules will explain the key process of segmentation, especially the technique of edge detection and thresholding which are the heart of 3D printing. CONCLUSION: This is likely to enable the practising orthopaedician and radiologist to set up a 3D printing unit in their departments or even standalone radiology centres at minimal startup costs. This will enable maximal utilisation of this technology that is likely to bring about a paradigm shift in planning, simulation, and execution of complex surgeries.

15.
Adv Biosyst ; 3(2): e1800103, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-32627375

RESUMO

Cell fate is largely determined by interactions that occur at the interface between cells and their surrounding microenvironment. For this reason, especially in the field of tissue-engineering, there is a growing interest in developing techniques that allow evaluating cell-material interaction at the nanoscale, particularly focusing on cell adhesion processes. While for 2D culturing systems a consolidated series of tools already satisfy this need, in 3D environments, more closely recapitulating complex in vivo structures, there is still a lack of procedures furthering the comprehension of cell-material interactions. Here, the use of scanning electron microscopy coupled with a focused ion beam (SEM/FIB) for the characterization of cell interactions with 3D scaffolds obtained by different fabrication techniques is reported for the first time. The results clearly show the capability of the developed approach to preserve and finely resolve scaffold-cell interfaces highlighting details such as plasma membrane arrangement, extracellular matrix architecture and composition, and cellular structures playing a role in cell adhesion to the surface. It is anticipated that the developed approach will be relevant for the design of efficient cell-instructive platforms in the study of cellular guidance strategies for tissue-engineering applications as well as for in vitro 3D models.


Assuntos
Adesão Celular/fisiologia , Técnicas Citológicas , Microscopia Eletrônica de Varredura , Engenharia Tecidual , Alicerces Teciduais , Células Cultivadas , Microambiente Celular , Matriz Extracelular/fisiologia , Humanos , Propriedades de Superfície
16.
Adv Mater ; 30(41): e1706755, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29774611

RESUMO

Nanoporous metallic networks are a group of porous materials made of solid metals with suboptical wavelength sizes of both particles and voids. They are characterized by unique optical properties, as well as high surface area and permeability of guest materials. As such, they attract a great focus as novel materials for photonics, catalysis, sensing, and renewable energy. Their properties together with the ability for scaling-up evoke an increased interest also in the industrial field. Here, fabrication techniques of large-scale metallic networks are discussed, and their interesting optical properties as well as their applications are considered. In particular, the focus is on disordered systems, which may facilitate the fabrication technique, yet, endow the three-dimensional (3D) network with distinct optical properties. These metallic networks bridge the nanoworld into the macroscopic world, and therefore pave the way to the fabrication of innovative materials with unique optoelectronic properties.

17.
Curr Drug Targets ; 19(4): 393-405, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-27033196

RESUMO

BACKGROUND: Nanomedicine is currently exploited for manufacturing therapeutic DDS and treatments protocols for various diseases and disorders. To obtain DDS, different types of materials are used, from organic to inorganic, polar to non-polar, micro to nanomaterials from 0D to 3D structured materials, respectively. Many of these materials were extensively studied and reviewed in the literature. OBJECTIVE: The objectives of this review is to make a clear overview on drug delivery systems depending several aspects related to delivery mechanisms, the type of supports, the active agents ant the potential applications in the prevention or treatment of various diseases. RESULTS: Following aspects are extensively debated: synthesis issues, characteristics and potential uses of 0, 1, 2 and 3D drug delivery systems according to their nature and applications. These systems can be can be tailored according to the delivery mechanism (0-3D delivery) as well as by using more active agents, with more therapeutic activity or same activity but with different mechanisms of action. The size and morphology of the drug delivery system is essential, especially when talking about the internalization into the tumor cells while the mobility is especially dependent on the size. The influence of the nature of the supports and their polarity was extensively studied during the last decades, as well as the importance of the porosity and pore size, but only limited papers are devoted to the holistic analysis of the dimensionality of the support and the ways of delivering the active agents. CONCLUSION: This review is devoted to a holistic insight into the drug delivery systems, from a new, only marginally studied point of view, meaning the dimensionality of the drug delivery systems and the characteristics of the delivery.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Animais , Portadores de Fármacos/síntese química , Humanos , Estrutura Molecular , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Porosidade , Nanomedicina Teranóstica
18.
Biosens Bioelectron ; 89(Pt 1): 187-200, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27020065

RESUMO

Hydrogels consisting of three-dimensional (3D) polymeric networks have found a wide range of applications in biotechnology due to their large water capacity, high biocompatibility, and facile functional versatility. The hydrogels with stimulus-responsive swelling properties have been particularly instrumental to realizing signal transduction in biosensors and bioelectronics. Graphenes are two-dimensional (2D) nanomaterials with unprecedented physical, optical, and electronic properties and have also found many applications in biosensors and bioelectronics. These two classes of materials present complementary strengths and limitations which, when effectively coupled, can result in significant synergism in their electrical, mechanical, and biocompatible properties. This report reviews recent advances made with hydrogel and graphene materials for the development of high-performance bioelectronics devices. The report focuses on the interesting intersection of these materials wherein 2D graphenes are hybridized with 3D hydrogels to develop the next generation biosensors and bioelectronics.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletrônica/instrumentação , Grafite/química , Hidrogéis/química , Nanoestruturas/química , Animais , Técnicas Biossensoriais/métodos , Capacitância Elétrica , Nariz Eletrônico , Eletrônica/métodos , Desenho de Equipamento , Humanos , Modelos Moleculares , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Transistores Eletrônicos
19.
Methods Mol Biol ; 1612: 29-37, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28634933

RESUMO

Altered tissue mechanical properties have been implicated in many key physiological and pathological processes. Hydrogel-based materials systems, made with native extracellular matrix (ECM) proteins, nonnative biopolymers, or synthetic polymers are often used to study these processes in vitro in 3D cell culture experiments. However, each of these materials systems present major limitations when used in mechanobiological studies. While native ECM-based hydrogels may enable good recapitulation of physiological behavior, the mechanics of these hydrogels are often manipulated by increasing or decreasing the protein concentration. This manipulation changes cell adhesion ligand density, thereby altering cell signaling. Alternatively, synthetic polymer-based hydrogels and nonnative biopolymer-based hydrogels can be mechanically tuned and engineered to present cell adhesion peptide motifs, but still may not fully promote physiologically relevant behavior. Here, we combine the advantages of native ECM proteins and nonnative biopolymers in interpenetrating network (IPN) hydrogels consisting of rBM matrix, which contains ligands native to epithelial basement membrane, and alginate, an inert biopolymer derived from seaweed. The following protocol details the generation of IPNs for mechanical testing or for 3D cell culture. This biomaterial system offers the ability to tune the stiffness of the 3D microenvironment without altering cell adhesion ligand concentration or pore size.


Assuntos
Alginatos/metabolismo , Materiais Biocompatíveis/metabolismo , Técnicas de Cultura de Células/métodos , Matriz Extracelular/metabolismo , Animais , Adesão Celular , Células Cultivadas , Proteínas da Matriz Extracelular/metabolismo , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo , Hidrogéis/química , Camundongos , Engenharia Tecidual
20.
MethodsX ; 3: 219-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27054098

RESUMO

Atomistic simulations have now become commonplace in the study of the deformation and failure of materials. Increase in computing power in recent years has made large-scale simulations with billions, or even trillions, of atoms a possibility. Most simulations to-date, however, are still performed with quasi-2D geometries or rather simplistic 3D setups. Although controlled studies on such well-defined structures are often required to obtain quantitative information from atomistic simulations, for qualitative studies focusing on e.g. the identification of mechanisms, researchers would greatly benefit from a methodology that helps realize more realistic configurations. The ideal scenario would be a one-on-one reconstruction of experimentally observed structures. To this end, we propose a new method and software tool called nano sculpt with the following features:•The method allows for easy sample generation for atomistic simulations from any arbitrarily shaped 3D enclosed volume.•The tool can be used to build atomistic samples from artificial geometries, including CAD geometries and structures obtained from simulation methods other than atomistic simulations.•The tool enables the generation of experimentally informed atomistic samples, by e.g. digitization of micrographs or usage of tomography data.

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