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1.
ACS Appl Mater Interfaces ; 13(33): 39126-39134, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34383476

RESUMO

The usage of exogenous antioxidant materials to relieve oxidative stress offers an important strategy for the therapy of oxidative stress-induced injuries. However, the fabrication processes toward the antioxidant materials usually require the involvement of extra metal ions and organic agents, as well as sophisticated purification steps, which might cause tremendous environmental stress and induce unpredictable side effects in vivo. To address these issues, herein, we proposed a novel strategy to fabricate green nanoparticles for efficiently modulating oxidative stress, which was facilely prepared from tea polyphenol extracts (originated from green tea) via a green enzymatic polymerization-based chemistry method. The resulting nanoparticles possessed a uniform spherical morphology and good stability in water and biomedium and demonstrated excellent radical scavenging properties. These nanoparticle scavengers could effectively prevent intracellular oxidative damage, accelerate wound recovery, and protect the kidneys from reactive oxygen species damaging in the acute kidney injury model. We hope this work will inspire the further development of more types of green nanoparticles for antioxidant therapies via similar synthetic strategies using green biomass materials.


Assuntos
Injúria Renal Aguda/prevenção & controle , Antioxidantes/química , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/química , Chá/química , Células 3T3 , Células A549 , Animais , Antioxidantes/farmacologia , Catecóis/química , Sobrevivência Celular/efeitos dos fármacos , Feminino , Sequestradores de Radicais Livres/metabolismo , Química Verde , Peroxidase do Rábano Silvestre/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica , Cicatrização/efeitos dos fármacos
2.
Small ; : e2102532, 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34302441

RESUMO

For the proliferation of the supercapacitor technology, it is essential to attain superior areal and volumetric performance. Nevertheless, maintaining stable areal/volumetric capacitance and rate capability, especially for thick electrodes, remains a fundamental challenge. Here, for the first time, a rationally designed porous monolithic electrode is reported with high thickness of 800 µm (46.74 mg cm-2 , with high areal mass loading of NiCo2 S4 6.9 mg cm-2 ) in which redox-active Ag nanoparticles and NiCo2 S4 nanosheets are sequentially decorated on highly conductive wood-derived carbon (WC) substrates. The hierarchically assembled WC@Ag@NiCo2 S4 electrode exhibits outstanding areal capacitance of 6.09 F cm-2 and long-term stability of 84.5% up to 10 000 cycles, as well as exceptional rate capability at 50 mA cm-2 . The asymmetric cell with an anode of WC@Ag and a cathode of WC@Ag@NiCo2 S4 delivers areal/volumetric energy density of 0.59 mWh cm-2 /3.93 mWh cm-3 , which is much-improved performance compared to those of most reported thick electrodes at the same scale. Theoretical calculations verify that the enhanced performance could be attributed to the decreased adsorption energy of OH- and the down-shifted d-band of Ag atoms, which can accelerate the electron transport and ion transfer.

3.
ACS Appl Mater Interfaces ; 13(18): 21272-21285, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33940792

RESUMO

Although eco-friendly amidoxime-based adsorbents own an excellent uranium (U)-adsorption capacity, their U-adsorption efficiency is commonly reduced and even damaged by the biological adhesion from bacteria/microorganisms in an aqueous environment. Herein, we present an antibiofouling ultrathin poly(amidoxime) membrane (AUPM) with highly enhanced U-adsorption performance, through dispersing the quaternized chitosan (Q-CS) and poly(amidoxime) in a cross-linked sulfonated cellulose nanocrystals (S-CNC) network. The cross-linked S-CNC not only can elevate the hydrophilicity to improve the U-adsorption efficiency of AUPM but also can enhance the mechanical strength to form a self-supporting ultrathin membrane (17.21 MPa, 10 µm thickness). More importantly, this AUPM owns a good antibiofouling property, owing to the broad-spectrum antibacterial quaternary ammonium groups of the Q-CS. As a result, within the 1.00 L of low-concentration (100 ppb) U-added pure water (pH ≈ 5) and seawater (pH ≈ 8) for 48 h, 30 mg of AUPM can recover 93.7% U and 91.4% U, respectively. Furthermore, compared with the U-absorption capacity of a blank membrane without the Q-CS, that of AUPM can significantly increase 37.4% reaching from 6.39 to 8.78 mg/g after being in natural seawater for only 25 d. Additionally, this AUPM can still maintain almost constant tensile strength during 10 cycles of adsorption-desorption, which indicates the relatively long-term usability of AUPM. This AUPM will be a promising candidate for highly efficient and large-scale U-recovery from both U-containing waste freshwater/seawater and natural seawater, which will be greatly helpful to deal with the U-pollution and enrich U for the consumption of nuclear power. More importantly, the work will provide a new convenient but universal strategy to fabricate new highly enhanced low-cost U-adsorbents, through the introduction of both an antibacterial property and a high mechanical performance, which will be a good reference for the design of new highly efficient U-adsorbents.


Assuntos
Incrustação Biológica/prevenção & controle , Membranas Artificiais , Oximas/química , Polímeros/química , Água do Mar/química , Urânio/isolamento & purificação , Águas Residuárias/química , Adsorção , Urânio/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-33538165

RESUMO

A solar steam generation method has been widely investigated as a sustainable method to achieve seawater desalination and sewage treatment. However, oil pollutants are usually emitted in real seawater or wastewaters, which can cause serious fouling problems to disturb the solar evaporation performance. In this work, a mussel-inspired, low-cost, polydopamine-filled cellulose aerogel (PDA-CA) has been rationally designed and fabricated with both superhydrophilicity and underwater superoleophobicity. The resulting PDA-CA device could also achieve a high solar evaporation rate of 1.36 kg m-1 h-1 with an 86% solar energy utilize efficiency under 1 sun illumination. In addition, the PDA-CA not only exhibited promising antifouling capacity for long-term water evaporation but also engaged in the effective adsorption of organic dye contaminants. These promising features of PDA-CA may offer new opportunities for developing multifunctional photothermal devices for solar-driven water remediation.

5.
Adv Mater ; 33(11): e2005569, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33538067

RESUMO

The rapid development of modern industry and excessive consumption of petroleum-based polymers have triggered a double crisis presenting a shortage of nonrenewable resources and environmental pollution. However, this has provided an opportunity to stimulate researchers to harness native biobased materials for novel advanced materials and applications. Nanocellulose-based aerogels, using abundant and sustainable cellulose as raw material, present a third-generation of aerogels that combine traditional aerogels with high porosity and large specific surface area, as well as the excellent properties of cellulose itself. Currently, nanocellulose aerogels provide a highly attention-catching platform for a wide range of functional applications in various fields, e.g., adsorption, separation, energy storage, thermal insulation, electromagnetic interference shielding, and biomedical applications. Here, the preparation methods, modification strategies, composite fabrications, and further applications of nanocellulose aerogels are summarized, with additional discussions regarding the prospects and potential challenges in future development.

6.
Environ Sci Pollut Res Int ; 28(24): 30898-30907, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33594553

RESUMO

The presence of volatile benzene series compounds (VBSCs) in the environment is continually increasing, with the potential for negative effects on human health. It is therefore important to develop new materials for the adsorption of these compounds using various modification techniques. Glass fibers are a promising adsorbent for VBSCs and offer a number of advantages. In the present work, the surfaces of glass fibers were modified using hydrogen peroxide, a sodium hydroxide solution, or Piranha solution (a mixture of concentrated sulfuric acid and hydrogen peroxide). The adsorption characteristics of the resulting specimens were investigated, employing 10 volatile benzene-based compounds, and the activated glass fibers showed significantly improved adsorption efficiencies. The fibers activated with the Piranha solution were further modified with a triethoxysilyl benzene compound to obtain an aryl-modified material that demonstrated enhanced adsorption of aniline, salicylaldehyde, benzyl alcohol, and xylene relative to that obtained from a combination of polyurethane foam and XAD-2 resin. The adsorption efficiency of benzyl alcohol by these aryl glass fibers was found to be as high as 93% and the adsorption mechanism is believed to be associated with hydrogen bonding and π-π conjugation. This study provides a reliable technique for the quantification of VBSCs and a basis for the evaluation of various adsorption materials.


Assuntos
Benzeno , Adsorção , Vidro , Humanos , Cinética , Termodinâmica
7.
ACS Omega ; 5(33): 20698-20706, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875203

RESUMO

o-Phenylenediamine (OPD) can be readily oxidized by several types of oxidants to generate fluorescent 2,3-diaminophenazine (oxidized OPD, OPDox). The unique fluorescence response process during the oxidation of OPD provides an important model for the design of novel sensors. In recent years, a series of fluorescent and colorimetric sensors have been developed based on the oxidation of OPD. In this review, fluorescent and colorimetric sensors for the detection of metal ions and small organic molecules are discussed. These sensing processes exhibit distinguishable and prominent fluorescent and colorimetric responses. The sensing systems include autocatalytic reactions and using nanomaterials, carbon dots, or fluorophore labeled DNA as reference fluorophore for fluorescent and colorimetric detection.

8.
ACS Appl Mater Interfaces ; 12(31): 35513-35522, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32672439

RESUMO

Nanocellulose-based porous materials have been recently considered as ideal candidates in various applications. However, challenges on performances remain owing to the disorderly structure and the limited transport specificity. Herein, wood-inspired composite sponges consisting of cellulose nanofibrils (CNFs) and high-aspect-ratio silver nanowires (AgNWs) were generated with anisotropic properties by the directional freeze-drying. The obtained composite sponges exhibited attractive features, such as an excellent compressive stress of 24.5 kPa, low percolation threshold of 0.1 vol % AgNWs, and high electrical conductivity of 1.52 S/cm. Furthermore, the self-assembled ordered structure in the longitudinal direction and synergistic effect between CNFs and AgNWs benefited the sponge interesting anisotropic electrical conductivity, thermal diffusivity, ultrafast electrically induced heating (<5 s), sensitive pressure sensing (errors <0.26%), and electromagnetic interference (EMI) shielding for special practical demands. This multifunctional material inspired by natural woods is expected to broaden new applications as electronic devices for an intelligent switch or EMI shielding.

9.
Front Chem ; 8: 89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32154215

RESUMO

Fatsia Japonica seed, which is mainly composed of glucose, has potential as a porous carbon matrix precursor for supercapacitors that can achieve high-value utilization. Cost-effective hierarchical porous carbon materials (HPC) were prepared from Fatsia Japonica by annealing at high temperature. The pore size and distribution of the HPC can be precisely controlled and adjusted by altering the activation temperature. The HPC obtained at 600°C showed favorable features for electrochemical energy storage, with a surface area of 870.3 m2/g. The HPC for supercapacitors (a three-electrode system) exhibited good specific capacitance of 140 F/g at a current density of 1 A/g and a long cycling life stability (87.5% remained after 10,000 cycles). In addition, the HPC electrode showed an excellent energy density of 23 Wh/Kg. Such hierarchical porous biomass-derived carbon would be a good candidate for application in the electrodes of supercapacitors due to its simple preparation process and the outstanding electrochemical performance.

10.
Nanomaterials (Basel) ; 10(1)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952146

RESUMO

Electrospinning is an effective and versatile method to prepare continuous polymer nanofibers and nonwovens that exhibit excellent properties such as high molecular orientation, high porosity and large specific surface area. Benefitting from these outstanding and intriguing features, electrospun nanofibers have been employed as a promising candidate for the fabrication of food packaging materials. Actually, the electrospun nanofibers used in food packaging must possess biocompatibility and low toxicity. In addition, in order to maintain the quality of food and extend its shelf life, food packaging materials also need to have certain functionality. Herein, in this timely review, functional materials produced from electrospinning toward food packaging are highlighted. At first, various strategies for the preparation of polymer electrospun fiber are introduced, then the characteristics of different packaging films and their successful applications in food packaging are summarized, including degradable materials, superhydrophobic materials, edible materials, antibacterial materials and high barrier materials. Finally, the future perspective and key challenges of polymer electrospun nanofibers for food packaging are also discussed. Hopefully, this review would provide a fundamental insight into the development of electrospun functional materials with high performance for food packaging.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 200: 339-344, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29709793

RESUMO

Quantitative explanation on the improved mechanical properties of aligned electrospun polyimide (PI) nanofibers as the increased imidization temperatures is highly required. In this work, polarized FT-IR spectroscopy is applied to solve this problem. Based on the polarized FT-IR spectroscopy and the molecular model in the fibers, the length of the repeat unit of PI molecule, the angle between the fiber axis and the symmetric stretching direction of carbonyl group on the imide ring, and the angle between the PI molecular axis and fiber axis are all investigated. The Mark-Howink equation is used to calculate the number-average molar mass of PI molecules. The orientation states of PI molecules in the electrospun nanofibers are studied from the number-average molar mass of PI molecules and the average fiber diameter. Quantitative analysis of the orientation factor of PI molecules in the electrospun nanofibers is performed by polarized FT-IR spectroscopy.

12.
Biomacromolecules ; 18(10): 3215-3221, 2017 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-28820944

RESUMO

Achieving high drug loading capacity and controlling drug delivery are two main challenges related to drug carriers. In this study, polymeric macroporous sponges with very high pore volume and large porosity are introduced as a new-type of drug carrier. Due to the high pore volume (285 and 166 cm3/g for the sponges with densities of 3.5 and 6.0 mg/cm3, respectively), the sponges exhibit very high drug loading capacities with average values of 1870 ± 114 and 2697 ± 73 mg/g in the present study, which is much higher than the meso and microporous drug carriers (<1500 mg/g). In order to control the release profiles, an additional poly(p-xylylene) (PPX) coating was deposited by chemical vapor deposition on the drug loaded sponge. Consequently, Artemisone (ART) release in the aqueous medium could be retarded, depending on the density of the sponge and the thickness of the coating. In future, the new 3D polymeric sponges would be highly beneficial as drug carriers for the programmed release of drugs for treatment of chronic diseases.


Assuntos
Artemisininas/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Polímeros/química , Porosidade , Volatilização , Xilenos/química
14.
Angew Chem Int Ed Engl ; 56(12): 3285-3288, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28194915

RESUMO

Ultralight cellular sponges offer a unique set of properties. We show here that solvent uptake by these sponges results in new gel-like materials, which we term spongy gels. The appearance of the spongy gels is very similar to classic organogels. Usually, organogels are formed by a bottom-up process. In contrast, the spongy gels are formed by a top-down approach that offers numerous advantages for the design of their properties, reproducibility, and stability. The sponges themselves represent the scaffold of a gel that could be filled with a solvent, and thereby form a mechanically stable gel-like material. The spongy gels are independent of a time-consuming or otherwise demanding in situ scaffold formation. As solvent evaporation from gels is a concern for various applications, we also studied solvent evaporation of wetting and non-wetting liquids dispersed in the sponge.

15.
Macromol Rapid Commun ; 38(3)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27879014

RESUMO

This study reports on gold nanoparticles (AuNPs) immobilized in a sponge made of short electrospun fibers (Au-sponge), which show surprisingly high reaction rates at extremely low gold amount. Au-sponges are made by freeze-drying of dispersions of short electrospun fibers with preimmobilization of AuNPs. The resulting Au-sponges show very low densities around 7 mg cm-3 corresponding to a pore volume of about 150 mL g-1 , but low surface area and very low amount of AuNPs in the range of 0.29-3.56 wt%. In general, catalysts with immobilized AuNPs show much low reaction rates compared to systems with dispersed AuNPs. By contrast, the Au-sponge catalyst with immobilized AuNPs is discerned here as an extremely efficient catalyst even superior to other systems with dispersed AuNPs. The fidelity of the Au-sponges after reactions is good enough for manifold use and thereby provides a sustainable catalyst design as well.


Assuntos
Benzofenonas/síntese química , Ouro/química , Nanopartículas Metálicas/química , Polivinil/síntese química , Benzofenonas/química , Catálise , Tamanho da Partícula , Polivinil/química , Propriedades de Superfície
16.
ACS Appl Mater Interfaces ; 6(8): 5918-23, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24684423

RESUMO

A combination of appropriate reinforcing material and morphology led to the highly tough, flexible, and strong polystyrene fibers by electrospinning. Concentric fiber morphology with reinforcing elastomeric thermoplastic polyurethane (TPU) sandwiched between the two layers of polystyrene made by a special nozzle (triaxial) showed toughness of >270 J g(-1) and 300% elongation without any cracks in comparison to toughness of <0.5 J g(-1) and elongation at break of <5% of polystyrene single fibers. The concentric triaxial morphology showed great advantage in comparison to the coaxial structure. Toughness and elongation at break were 1376 and 628% higher, respectively, for triaxial morphology in comparison to the coaxial fibers because of the better interface from the sandwich structure.

17.
ACS Appl Mater Interfaces ; 4(8): 4366-72, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22817392

RESUMO

We highlight a novel composite fabrication method based on solution casting, electrospinning, and film stacking for preparing highly transparent nylon-6 nanofiber reinforced thermoplastic polyurethane (TPU) composite films. The procedure is simple and can be extended to the other thermoplastics. The morphology of fiber/matrix interface and the properties of composite films were also investigated. The method led to a significant reinforcement in mechanical properties of TPU like tensile strength, E modulus, strain, and toughness just using very small amounts of nylon fibers (about 0.4-1.7 wt %; 150-300 nm diameter). The enhanced mechanical properties were achieved without sacrificing optical properties like transparency of TPU.


Assuntos
Materiais Biocompatíveis/química , Caprolactama/análogos & derivados , Nanofibras/química , Plásticos/química , Polímeros/química , Poliuretanos/química , Caprolactama/química , Resinas Compostas/química , Módulo de Elasticidade , Teste de Materiais , Modelos Químicos , Nanocompostos/química , Óptica e Fotônica/métodos , Solventes/química , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração
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