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1.
Mol Cell Proteomics ; 22(11): 100657, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37805037

RESUMO

Mitochondria are densely packed with proteins, of which most are involved physically or more transiently in protein-protein interactions (PPIs). Mitochondria host among others all enzymes of the Krebs cycle and the oxidative phosphorylation pathway and are foremost associated with cellular bioenergetics. However, mitochondria are also important contributors to apoptotic cell death and contain their own genome indicating that they play additionally an eminent role in processes beyond bioenergetics. Despite intense efforts in identifying and characterizing mitochondrial protein complexes by structural biology and proteomics techniques, many PPIs have remained elusive. Several of these (membrane embedded) PPIs are less stable in vitro hampering their characterization by most contemporary methods in structural biology. Particularly in these cases, cross-linking mass spectrometry (XL-MS) has proven valuable for the in-depth characterization of mitochondrial protein complexes in situ. Here, we highlight experimental strategies for the analysis of proteome-wide PPIs in mitochondria using XL-MS. We showcase the ability of in situ XL-MS as a tool to map suborganelle interactions and topologies and aid in refining structural models of protein complexes. We describe some of the most recent technological advances in XL-MS that may benefit the in situ characterization of PPIs even further, especially when combined with electron microscopy and structural modeling.


Assuntos
Mitocôndrias , Proteoma , Proteoma/metabolismo , Espectrometria de Massas/métodos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Reagentes de Ligações Cruzadas/química
2.
Small ; 20(4): e2307553, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37715063

RESUMO

In situ forming gel polymer electrolyte (GPE) is one of the most feasible ways to improve the safety and cycle performances of lithium metal batteries with high energy density. However, most of the in situ formed GPEs are not compatible with high-voltage cathode materials. Here, this work provides a novel strategy to in situ form GPE based on the mechanism of Ritter reaction. The Ritter reaction in liquid electrolyte has the advantage of appropriate reaction temperature and no additional additives. The polymer chains are cross-linked by amide groups with the formation of GPE with superior electrochemical properties. The GPE has high ionic conductivity (1.84 mS cm-1 ), wide electrochemical stability window (>5.25 V) and high lithium ion transference number (≈0.78), compatible with high-voltage cathode materials. The Li|LiNi0.6 Co0.2 Mn0.2 O2 batteries with in situ formed GPE show excellent long-term cycle stability (93.4%, 300 cycles). The density functional theory calculation and X-ray photoelectron spectroscopy results verify that the amide and nitrile groups are beneficial for stabilizing cathode structure and promoting uniform Li deposition on Li anode. Furthermore, the in situ formed GPE exhibits excellent electrochemical performance in Graphite|LiMn2 O4 and Graphite|LiNi0.5 Co0.2 Mn0.3 O2 pouch batteries. This approach is adaptable to current battery technologies, which will be sure to promote the development of high energy-density lithium-ion batteries.

3.
Biopolymers ; : e23628, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39301862

RESUMO

Bone tissue engineering is a promising technology being studied globally to become an effective and sustainable method to treat the problems of damaged or diseased bones. In this work, we developed an in situ cross-linking hydrogel system that combined N-succinyl chitosan (NSC) and oxidized alginate (OA) at varying mixing ratios through Schiff base cross-linking. The hydrogel system also contains biphasic calcium phosphate (BCP) and ascorbic acid (AA), which could enhance biological characteristics and accelerate bone repair. The hydrogels' properties were examined through physicochemical tests such as scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), x-ray diffraction (XRD), pore size and porosity measurement, swelling ratio, degradation rate, AA release study, as well as cytocompatibility, including live/dead and cytotoxicity assays. The results revealed that the supplementation of AA and BCP components can affect the physico-mechanical properties of the hydrogel system. However, they exhibited noncytotoxic properties. Overall, the results demonstrated that the hydrogel composed of 3% (w/v) NSC and 3% (w/v) OA (NSC: OA volume ratio is 8:2) loaded with 40% (w/w) BCP and 0.3 mg/mL AA has the potential for bone regeneration.

4.
Small ; 19(50): e2304189, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37626466

RESUMO

The perovskite solar cells (PSCs) have achieved great success in power conversion efficiency due to their excellent optoelectrical properties of perovskite. However, the instability of PSCs severely impedes their commercialization. Recently, in situ cross-linking strategy has been proposed to mitigate stability issues of PSCs, enabling highly efficient and stable PSCs. Here, the critical factors that lead to the degradation of PSCs are first outlined. Then, a comprehensive review of in situ cross-linking strategy in perovskite to enhance the moisture, thermal, illumination, and bending stress resistance properties of PSCs is presented. Furthermore, the detailed mechanism underlying these advantageous effects is discussed pertaining to crystallization regulation, immobilization of ions, water resistance, and release of unfavorable stress. Finally, the current challenges and further development trends of in situ cross-linking strategy in PSCs and extension to other optoelectronic devices are prospected.

5.
Macromol Rapid Commun ; 44(10): e2200865, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37016473

RESUMO

Lithium-ion batteries (LIBs) have become the research focus of energy storage products. Due to the combination of Li+ and the Lewis basic sites of polymer chains, anions move more than five times faster, which do not participate in the electrode reaction during the discharge cycles, leading to concentration polarization, voltage losses, and high internal resistance. To solve this phenomenon, in this work, a polymer network structure of single-ion polymer electrolyte-based polyimide (DPI-SIGPE) with plasticizer ethylene carbonate (EC)/dimethyl carbonate (DMC) is formed by in-situ cross-linking double bond polyimide, 4-styrene sulfonyl (benzenesulfonyl) imide, and cross-linking agent pentaerythritol tetra(2-thiol acetate) under UV irradiation. By incorporating the anion as a part of the polymer chain, DPI-SIGPE exhibits high lithium-ion conductivity of 2.7 × 10-4 S cm-1 at 30 °C and transference number of 0.87. Typical lithium stripping/plating cycling of 900 h demonstrates uniform lithium deposition impacted by DPI-SIGPE. Meanwhile, it has good dimensional thermal stability with no obvious shrinkage at 200 °C for 0.5 h and wide electrochemical window of 4.6 V. Thus, the polyimide-based cross-linked single-ion gel polymer electrolyte has the promising potential for application in LIBs.


Assuntos
Eletrólitos , Lítio , Íons , Condutividade Elétrica , Polímeros
6.
Angew Chem Int Ed Engl ; 62(52): e202310975, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37950819

RESUMO

Activatable dual-modal molecular imaging probes present a promising tool for the diagnosis of malignant tumors. However, synchronously enhancing dual-modal imaging signals under a single stimulus is challenging. Herein, we propose an activatable bimodal probe that integrates aggregation-induced emission luminogens (AIEgens) and iron oxide nanoparticles (IOs) to synergistically enhance near-infrared fluorescence (NIRF) intensity and magnetic resonance (MR) contrast through a tumor acidity-mediated click reaction. Tumor acidity-responsive IOs containing dibenzocyclooctyne groups (termed cDIOs) and AIEgens containing azide groups (termed AATs) can be covalently cross-linked in response to tumor acidity, which leads to a simultaneous enhancement in NIRF intensity (≈12.4-fold) and r2 relaxivity (≈2.8-fold). cDIOs and AATs were effectively activated in mice orthotropic breast tumor, and the cross-linking prolonged their retention in tumor, further augmenting the bimodal signals and expanding imaging time frame. This facile strategy leverages the inherent properties of probes themselves and demonstrates promise in future translational studies.


Assuntos
Nanopartículas , Neoplasias , Camundongos , Animais , Sondas Moleculares , Imageamento por Ressonância Magnética/métodos , Imagem Molecular , Nanopartículas Magnéticas de Óxido de Ferro , Imagem Óptica/métodos
7.
Mikrochim Acta ; 187(12): 655, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33180194

RESUMO

Hg2+-sensitive carbon dots (CDs) were synthesized by microwave-assisted pyrolysis of citric acid, sodium fluoride, and urea. The CDs as a signal report unit and rhodamine B (RhB) as a reference were then encapsulated in a nanosphere of chitosan assembled by a nonsolvent-induced chitosan colloidal formation and in situ cross-linking to construct a ratiometric probe for Hg2+ (chitosan-CDs-RhB). Interestingly, without any assistance from acids to improve the solubility of chitosan, the nanosphere containing CDs and RhB had an ultrasmall size of 9.7 nm with only approximately 1.1-nm-thick layers of chitosan enclosing one dot. In order to keep the residual functional groups on the nanosphere from compromising the fluorescence response of CDs to Hg2+, Co2+ was used as a fluorescently intact metal ion to saturate the functional groups. The saturated chitosan-CDs-RhB was thus potentially developed for determining Hg2+ in the fruit bodies and mycelia of edible and medicinal fungi. Limits of detection (LODs) of 2.24, 5.29, and 2.03 µM and recoveries in the ranges 98.3 to 101.8%, 99.5 to 104.6%, and 97.4 to 100.9% were estimated for the determination of Hg2+ in the fruit bodies of Pleurotus ostreatus, Lentinus edodes, and Hypsizygus marmoreus, respectively. Chitosan-CDs-RhB was further developed as a fluorescent ratiometric probe for quantitatively determining intracellular Hg2+ in fungal mycelia with a linear calibration curve of RIgreen/Ired = - 0.145c + 1.69 within the range 0.013 to 0.356 µg g-1. Graphical abstract An ultrasmall chitosan nanosphere encapsulating carbon dots and rhodamine B as a ratiometric probe for the determination of Hg2+.


Assuntos
Carbono/química , Quitosana/química , Mercúrio/análise , Sondas Moleculares/química , Nanosferas/química , Nanosferas/toxicidade , Pontos Quânticos/química , Rodaminas/química , Limite de Detecção , Microscopia Eletrônica de Transmissão , Pholiota/química , Pholiota/efeitos dos fármacos , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos , Difração de Raios X
8.
Adv Exp Med Biol ; 1058: 327-355, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29691829

RESUMO

Injectable hydrogels have demonstrated being a promising strategy for cartilage and bone tissue engineering applications, owing to their minimal invasive injection procedure, easy incorporation of cells and bioactive molecules, improved contact with the surrounding tissues and ability to match defects with complex irregular shapes, characteristics of osteoarthritic pathology. These unique properties make them highly suitable bioscaffolds for treating defects which are otherwise not easily accessible without and invasive surgical procedure. In this book chapter it has been summarized the novel appropriate injectable hydrogels for cartilage and bone tissue engineering applications of the last few years, including the most commonly used materials for the preparation, both natural and synthetic, and their fabrication techniques. The design of a suitable injectable hydrogel with an adequate gelation time that gathers perfect bioactive, biocompatible, biodegradable and good mechanical properties for clinical repair of damaged cartilage and bone tissue is a challenge of significant medical interest that remain to be achieved.


Assuntos
Materiais Biocompatíveis/química , Regeneração Óssea , Osso e Ossos , Cartilagem , Reagentes de Ligações Cruzadas/química , Hidrogéis/química , Alicerces Teciduais/química , Animais , Osso e Ossos/lesões , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Cartilagem/lesões , Cartilagem/metabolismo , Cartilagem/patologia , Humanos
9.
Biochem J ; 473(21): 3889-3901, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27551108

RESUMO

Transglutaminase 2 (TG2) is a ubiquitously expressed multifunctional member of the transglutaminase enzyme family. It has been implicated to have roles in many physiological and pathological processes such as differentiation, apoptosis, signal transduction, adhesion and migration, wound healing and inflammation. Previous studies revealed that TG2 has various intra- and extra-cellular interacting partners, which contribute to these processes. In the present study, we identified a molecular co-chaperone, DNAJA1, as a novel interacting partner of human TG2 using a GST pull-down assay and subsequent mass spectrometry analysis, and further confirmed this interaction via ELISA and surface plasmon resonance measurements. Interaction studies were also performed with domain variants of TG2 and results suggest that the catalytic core domain of TG2 is essential for the TG2-DNAJA1 interaction. Cross-linking activity was not essential for the interaction since DNAJA1 was also found to interact with the catalytically inactive form of TG2. Furthermore, we have showed that DNAJA1 interacts with the open form of TG2 and regulates its transamidation activity under both in vitro and in situ conditions. We also found that DNAJA1 is a glutamine donor substrate of TG2. Since DNAJA1 and TG2 are reported to regulate common pathological conditions such as neurodegenerative disorders and cancer, the findings in the present paper open up possibilities to explore molecular mechanisms behind TG2-regulated functions.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Transglutaminases/metabolismo , Aminas/metabolismo , Ensaio de Imunoadsorção Enzimática , Glutamina/metabolismo , Células HEK293 , Humanos , Imuno-Histoquímica , Ligação Proteica , Proteína 2 Glutamina gama-Glutamiltransferase , Estabilidade Proteica , Ressonância de Plasmônio de Superfície , Espectrometria de Massas em Tandem
10.
ACS Appl Mater Interfaces ; 16(29): 38458-38465, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39008897

RESUMO

Although silicon (Si) has a high theoretical capacity, the large volume expansion during lithiation has greatly hindered its application in high-energy-density lithium-ion batteries (LIBs). Among the strategies for improving the performance of Si anode, the role of binders should not be underestimated. Here, a novel strategy for designing a cross-linkable binder for Si anode has been proposed. The binder with hydroxyl and nitrile groups can be in situ covalently cross-linked through the amide group in the batteries. The cross-linked binder (c-POAH) shows high elasticity and strong adhesion to Si particles and the current collector. Si||Li half coin cells using the c-POAH binder have excellent cycle performance and the capacity retention ratio is 67.1% after 100 cycles at 0.2 C. Scanning electronic microscopy images show that the c-POAH binder can contribute to suppressing the pulverization of the Si anode. Moreover, the investigation with X-ray photoelectronic spectrum demonstrates that the decomposition of the liquid electrolyte on Si anode has been mitigated and the c-POAH binder can promote the formation of a more stable SEI film. Our strategy of endowing the binder with good elasticity through in situ cross-linking has opened up a new route for developing binders, which will definitely promote the application of Si anodes in high-energy-density LIBs.

11.
Macromol Biosci ; 24(8): e2400051, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38663437

RESUMO

Bioactive scaffolds capable of simultaneously repairing osteochondral defects remain a big challenge due to the heterogeneity of bone and cartilage. Currently modular microgel-based bioassembly scaffolds are emerged as potential solution to this challenge. Here, microgels based on methacrylic anhydride (MA) and dopamine modified gelatin (GelMA-DA) are loaded with chondroitin sulfate (CS) (the obtained microgel named GC Ms) or bioactive glass (BG) (the obtained microgel named GB Ms), respectively. GC Ms and GB Ms show good biocompatibility with BMSCs, which suggested by the adhesion and proliferation of BMSCs on their surfaces. Specially, GC Ms promote chondrogenic differentiation of BMSCs, while GB Ms promote osteogenic differentiation. Furthermore, the injectable GC Ms and GB Ms are assembled integrally by bottom-up in situ cross-linking to obtain modular microgel-based bioassembly scaffold (GC-GB/HM), which show a distinct bilayer structure and good porous properties and swelling properties. Particularly, the results of in vivo and in vitro experiments show that GC-GB/HM can simultaneously regulate the expression levels of chondrogenic- and osteogenesis-related genes and proteins. Therefore, modular microgel-based assembly scaffold in this work with the ability to promote bidirectional differentiation of BMSCs and has great potential for application in the minimally invasive treatment of osteochondral tissue defects.


Assuntos
Diferenciação Celular , Condrogênese , Células-Tronco Mesenquimais , Microgéis , Osteogênese , Alicerces Teciduais , Osteogênese/efeitos dos fármacos , Alicerces Teciduais/química , Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Animais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Microgéis/química , Gelatina/química , Gelatina/farmacologia , Coelhos , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Proliferação de Células/efeitos dos fármacos , Engenharia Tecidual/métodos
12.
ACS Appl Mater Interfaces ; 15(42): 48930-48944, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37827196

RESUMO

An increasing number of studies have shown that the local release of nitric oxide (NO) from hydrogels stimulates tissue regeneration by modulating cell proliferation, angiogenesis, and inflammation. The potential biomedical uses of NO-releasing hydrogels can be expanded by enabling their application in a fluid state, followed by controlled gelation triggered by an external factor. In this study, we engineered a hydrogel composed of methacrylated hyaluronic acid (HAGMA) and thiolated gelatin (GELSH) with the capacity for in situ photo-cross-linking, coupled with localized NO release. To ensure a gradual and sustained NO release, we charged the hydrogels with poly(l-lactic-co-glycolic acid) (PLGA) nanoparticles functionalized with S-nitrosoglutathione (GSNO), safeguarding SNO group integrity during photo-cross-linking. The formation of thiol-ene bonds via the reaction between GELSH's thiol groups and HAGMA's vinyl groups substantially accelerated gelation (by a factor of 6) and increased the elastic modulus of hydrated hydrogels (by 1.9-2.4 times). HAGMA/GELSH hydrogels consistently released NO over a 14 day duration, with the release of NO depending on the hydrogels' equilibrium swelling degree, determined by the GELSH-to-HAGMA ratio. Biocompatibility assessments confirmed the suitability of these hydrogels for biological applications as they display low cytotoxicity and stimulated fibroblast adhesion and proliferation. In conclusion, in situ photo-cross-linkable HAGMA/GELSH hydrogels, loaded with PLGA-GSNO nanoparticles, present a promising avenue for achieving localized and sustained NO delivery in tissue regeneration applications.


Assuntos
Gelatina , Ácido Hialurônico , Ácido Hialurônico/química , Gelatina/química , Óxido Nítrico , Hidrogéis/farmacologia , Hidrogéis/química , Compostos de Sulfidrila/química
13.
Adv Sci (Weinh) ; 10(30): e2302144, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37587798

RESUMO

Silicon has garnered significant attention as a promising anode material for high-energy density Li-ion batteries. However, Si can be easily pulverized during cycling, which results in the loss of electrical contact and ultimately shortens battery lifetime. Therefore, the Si anode binder is developed to dissipate the enormous mechanical stress of the Si anode with enhanced mechanical properties. However, the interfacial stability between the Si anode binder and Cu current collector should also be improved. Here, a multifunctional thiourea polymer network (TUPN) is proposed as the Si anode binder. The TUPN binder provides the structural integrity of the Si anode with excellent tensile strength and resilience due to the epoxy-amine and silanol-epoxy covalent cross-linking, while exhibiting high extensibility from the random coil chains with the hydrogen bonds of thiourea, oligoether, and isocyanurate moieties. Furthermore, the robust TUPN binder enhances the interfacial stability between the Si anode and current collector by forming a physical interaction. Finally, the facilitated Li-ion transport and improved electrolyte wettability are realized due to the polar oligoether, thiourea, and isocyanurate moieties, respectively. The concept of this work is to highlight providing directions for the design of polymer binders for next-generation batteries.

14.
Gels ; 9(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36661825

RESUMO

Bioartificial hydrogels are hydrophilic systems extensively studied for regenerative medicine due to the synergic combination of features of synthetic and natural polymers. Injectability is another crucial property for hydrogel mini-invasive administration. This work aimed at engineering injectable bioartificial in situ cross-linkable hydrogels by implementing green and eco-friendly approaches. Specifically, the versatile poly(ether urethane) (PEU) chemistry was exploited for the development of an amphiphilic PEU, while hyaluronic acid was selected as natural component. Both polymers were functionalized to expose thiol and catechol groups through green water-based carbodiimide-mediated grafting reactions. Functionalization was optimized to maximize grafting yield while preserving group functionality. Then, polymer miscibility was studied at the macro-, micro-, and nano-scale, suggesting the formation of hydrogen bonds among polymeric chains. All hydrogels could be injected through G21 and G18 needles in a wide temperature range (4-25 °C) and underwent sol-to-gel transition at 37 °C. The addition of an oxidizing agent to polymer solutions did not improve the gelation kinetics, while it negatively affected hydrogel stability in an aqueous environment, suggesting the occurrence of oxidation-triggered polymer degradation. In the future, the bioartificial hydrogels developed herein could find application in the biomedical and aesthetic medicine fields as injectable formulations for therapeutic agent delivery.

15.
Int J Biol Macromol ; 242(Pt 1): 124729, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37148942

RESUMO

To improve the stability of the soybean protein isolate/chitosan/sodium alginate ternary complex coacervate phase against environmental pH and ionic strength, the complex ternary phase cross-linked by Ca2+ was characterized and evaluated. The viscoelastic properties, thermal properties, microstructure, and texture profile were characterized using rheology, differentia scanning calorimetry as well as thermmogravimetric analysis, scanning electron microscopy as well as transmission electron microscopy, and texture profile analysis, respectively. Compared with the uncross-linked ternary complex coacervate, the complex in situ cross-linked with 1.0 % Ca2+ for 1 h still retains its typical solid characteristics, and has a more compact network structure and better stability. Our research results also showed that prolonging the cross-linking time (from 3 h to 5 h) and increasing the concentration of the cross-linking agent (from 1.5 % to 2.0 %) did not further improve the rheological, thermodynamic and textural properties of the complex coacervate. The ternary complex coacervate phase cross-linked in situ under 1.5 % concentration of Ca2+ for 3 h showed significantly improved stability at low pH 1.5-3.0, which indicats that the ternary complex coacervate phase cross-linked in situ by Ca2+ can be used as a potential delivery platform for the effective delivery of biomolecules under physiological conditions.


Assuntos
Quitosana , Proteínas de Soja , Proteínas de Soja/química , Quitosana/química , Alginatos/química
16.
Colloids Surf B Biointerfaces ; 218: 112756, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35988312

RESUMO

High efficiency of in-situ cross-linking and acid triggered drug delivery is realized by introducing tobramycin into the hydrogels. Injectable and biodegradable hydrogels are prepared through two steps: First generation of reactive aldehyde groups in the sodium alginate (A-Alg) and then introduction of antibiotic tobramycin as cross-linker. Due to the formation of dynamic Schiff base bonds between the amino groups in tobramycin and aldehyde groups in A-Alg, the gelation of hydrogels can be realized immediately. Thus, tobramycin acts well as the first role cross-linker and the hydrogels containing tobramycin can be injected into the wound during the treatment. In addition, the acid from the decomposition of organic compounds by the bacteria can break the cross-linking points previously formed by tobramycin in the hydrogels. Therefore, tobramycin can be released and act as the second role model drug to kill the bacteria. Because the hydrogels network is broken, the release of tobramycin is more efficient than the traditional drug delivery from hydrogels by diffusion. Based on these unique properties, the present hydrogels containing tobramycin exhibit a good injectable and biodegradable capability. In addition, due to the existence of the reversible acid-labile linkages in the hydrogels, the hydrogels containing tobramycin are also self-healing, which additionally is favorable for the application of wound dressing. More importantly, the antibacterial hydrogels also demonstrate good biocompatibility in vitro and significantly therapeutic effects on an infected mice model in vivo. Based on the above special properties, the hydrogels cross-linked by tobramycin indicate a new approach to prepare hydrogel dressings with low-cost, non-toxicity and good anti-bacterial performance in the treatment of infectious wounds.


Assuntos
Hidrogéis , Tobramicina , Aldeídos , Alginatos/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Hidrogéis/química , Camundongos , Bases de Schiff/química , Tobramicina/farmacologia
17.
Polymers (Basel) ; 14(23)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36501689

RESUMO

Waterproof breathable functional membranes have broad application prospects in the field of outdoors textiles. The fluorine-containing microporous membranes of the mainstream functional products easily cause harm to the environment, and thus, the fluorine-free environmental nanofibrous membranes are an important development direction for functional membranes. In this subject, the electrospun polyacrylonitrile nanofibrous membranes were first hydrophobically modified by amino functional modified polysiloxane (AMP), followed by in situ cross-linking modified with 4, 4'-methyl diphenylene diisocyanate (MDI). The fluorine-free modification by AMP altered the surface of the membranes from hydrophilic to hydrophobic, and greatly improved the waterproof properties with the hydrostatic pressure reaching to 87.6 kPa. In addition, the formation of bonding points and the in situ preparation of polyuria through the reaction between the isocyanate in MDI and the amino group in AMP, could improve the mechanical properties effectively. When using AMP with the concentration of 1 wt% and MDI with the concentration of 2 wt%, the relatively good comprehensive performance was obtained with good water resistance (93.8 kPa), modest vapor permeability (4.7 kg m-2 d-1) and air permeability (12.7 mm/s). Based on these testing data, the modified nanofibrous membranes had excellent waterproof and breathable properties, which has future potential in outdoor sports apparel.

18.
Colloids Surf B Biointerfaces ; 197: 111370, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33049661

RESUMO

A facile methodology was explored by using glutaraldehyde as a cross-linking reagent for in situ modification of polyvinyl alcohol (PVA) electrospun nanofibers doped with monodisperse silver nanoparticles (AgNPs) via the one-pot reactions. The hydroxyl groups along the PVA molecule chains can serve as both the reactive sites and stabilizers for AgNPs. Meanwhile, the cross-linking degree can be easily tuned by controlling the charged amounts of glutaraldehyde to obtain either partial or cured cross-linked PVA nanofibrous mats doped with AgNPs. It was revealed that such different cross-linking degrees could effectively control the release contents and rates of the embedded Ag to the surrounding aqueous solution. Furthermore, such release behavior was also found to be pH-responsive and acid-labile due to the formation of acetal groups during the cross-linking reactions. Besides both the partial and cured cross-linked PVA doped with Ag nanoparticles can still bear good antibacterial efficacy against S. aureus while have low cytotoxicity against mouse embryo fibroblasts (NIH3T3), human embryonic kidney cells (293T) and human histiocytic lymphoma cells (U937).


Assuntos
Nanopartículas Metálicas , Nanofibras , Animais , Antibacterianos/farmacologia , Preparações de Ação Retardada , Camundongos , Células NIH 3T3 , Álcool de Polivinil , Prata , Staphylococcus aureus
19.
ACS Appl Mater Interfaces ; 13(41): 49313-49321, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34617723

RESUMO

Silicon oxide (SiOx, 0 < x < 2) is considered one of the most promising anode materials for next-generation lithium-ion batteries due to its high theoretical capacity. However, its commercial application is limited by the non-negligible volume change during cycling. Herein, a three-dimensional (3D) structure of carboxymethyl cellulose (CMC) cross-linked with iminodiacetic (c-CMC-IDA150) was facilely formed through in situ thermal cross-linking of CMC and iminodiacetic acid (IDA) in the fabrication process of the electrode, which could construct a robust network to restrain the volume change of the SiOx anode and maintain the integrity of the electrode. In addition, the 3D cross-linked c-CMC-IDA150 provides sufficient contact sites to improve the adhesive strength. Thus, SiOx@c-CMC-IDA150 shows a prolonged cycle life, achieving a capacity of 1020 mAh g-1 after 100 cycles at a current density of 0.2 A g-1. With the increase in the current density to 1.0 A g-1, SiOx@c-CMC-IDA150 exhibits a reversible capacity of 899 mAh g-1 after 200 cycles with a capacity retention of 70.2%. This work provides a potential perspective to fabricate high-performance SiOx anodes and promote the stability of high-capacity Si-based anodes.

20.
ACS Appl Mater Interfaces ; 13(30): 35664-35676, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34284586

RESUMO

Commercial lithium-ion batteries are vulnerable to fire accidents, mainly due to volatile and flammable liquid electrolytes. Although solid polymer electrolytes (SPEs) are considered promising alternatives with antiflammability and processability for roll-to-roll mass production, several requirements have not yet been fulfilled for a viable lithium polymer battery. Such requirements include ionic conductivity, electrochemical stability, and interfacial resistance. In this work, the ionic conductivity of the SPEs is optimized by controlling the molecular weight and structural morphology of the plasticizers as well as introducing propylene oxide (PO) groups. Electrochemical stability is also enhanced using ethylene oxide (EO)/PO copolymer electrolytes, making the SPEs compatible with high-Ni LiNixCoyMn1-x-yO2 cathodes. The in situ cross-linking method, in which a liquid precursor first wets the electrode and is then solidified by a subsequent thermal treatment, enables the SPEs to soak into the 60 µm thick electrode with a high loading density of more than 8 mg cm-2. Thus, interfacial resistance between the SPE and the electrode is minimized. By using the in situ cross-linked EO/PO copolymer electrolytes, we successfully demonstrate a 4 V class lithium polymer battery, which performs stable cycling with a marginal capacity fading even over 100 cycles.

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