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1.
Angew Chem Int Ed Engl ; : e202406597, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757727

RESUMO

Artificial interfaces provide a comprehensive approach to controlling zinc dendrite and surface corrosion in zinc-based aqueous batteries (ZABs). However, due to consistent volume changes during zinc plating/stripping, traditional interfacial layers cannot consistently adapt to the dendrite surface, resulting in uncontrolled dendrite growth and hydrogen evolution. Herein, dynamic covalent bonds exhibit the Janus effect towards zinc deposition at different current densities, presenting a holistic strategy for stabilizing zinc anode. The PBSC intelligent artificial interface consisting of dynamic B-O covalent bonds is developed on zinc anode to mitigate hydrogen evolution and restrict dendrite expansion. Owing to the reversible dynamic bonds, PBSC exhibits shape self-adaptive characteristics at low current rates, which rearranges the network to accommodate volume changes during zinc plating/stripping, resisting hydrogen evolution. Moreover, the rapid association of B-O dynamic bonds enhances mechanical strength at dendrite tips, presenting a shear-thickening effect and suppressing further dendrite growth at high current rates. Therefore, the assembled symmetrical battery with PBSC maintains a stable cycle of 4500 hours without significant performance degradation and the PBSC@Zn||V2O5 pouch cell demonstrates a specific capacity exceeding 170 mAh g-1. Overall, the intelligent interface with dynamic covalent bonds provides innovative approaches for zinc anode interfacial engineering and enhances cycling performance.

2.
Adv Mater ; : e2403078, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38583072

RESUMO

Composite polymer solid electrolytes (CPEs), possessing good rigid flexible, are expected to be used in solid-state lithium-metal batteries. The integration of fillers into polymer matrices emerges as a dominant strategy to improve Li+ transport and form a Li+-conducting electrode-electrolyte interface. However, challenges arise as traditional fillers: 1) inorganic fillers, characterized by high interfacial energy, induce agglomeration; 2) organic fillers, with elevated crystallinity, impede intrinsic ionic conductivity, both severely hindering Li+ migration. Here, a concept of super-ionic conductor soft filler, utilizing a Li+ conductivity nanocellulose (Li-NC) as a model, is introduced which exhibits super-ionic conductivity. Li-NC anchors anions, and enhances Li+ transport speed, and assists in the integration of cathode-electrolyte electrodes for room temperature solid-state batteries. The tough dual-channel Li+ transport electrolyte (TDCT) with Li-NC and polyvinylidene fluoride (PVDF) demonstrates a high Li+ transfer number (0.79) due to the synergistic coordination mechanism in Li+ transport. Integrated electrodes' design enables stable performance in LiNi0.5Co0.2Mn0.3O2|Li cells, with 720 cycles at 0.5 C, and 88.8% capacity retention. Furthermore, the lifespan of Li|TDCT|Li cells over 4000 h and Li-rich Li1.2Ni0.13Co0.13Mn0.54O2|Li cells exhibits excellent performance, proving the practical application potential of soft filler for high energy density solid-state lithium-metal batteries at room temperature.

3.
Adv Mater ; : e2400508, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38452342

RESUMO

The confinement effect, restricting materials within nano/sub-nano spaces, has emerged as an innovative approach for fundamental research in diverse application fields, including chemical engineering, membrane separation, and catalysis. This confinement principle recently presents fresh perspectives on addressing critical challenges in rechargeable batteries. Within spatial confinement, novel microstructures and physiochemical properties have been raised to promote the battery performance. Nevertheless, few clear definitions and specific reviews are available to offer a comprehensive understanding and guide for utilizing the confinement effect in batteries. This review aims to fill this gap by primarily summarizing the categorization of confinement effects across various scales and dimensions within battery systems. Subsequently, the strategic design of confinement environments is proposed to address existing challenges in rechargeable batteries. These solutions involve the manipulation of the physicochemical properties of electrolytes, the regulation of electrochemical activity, and stability of electrodes, and insights into ion transfer mechanisms. Furthermore, specific perspectives are provided to deepen the foundational understanding of the confinement effect for achieving high-performance rechargeable batteries. Overall, this review emphasizes the transformative potential of confinement effects in tailoring the microstructure and physiochemical properties of electrode materials, highlighting their crucial role in designing novel energy storage devices.

4.
Talanta ; 226: 122101, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676657

RESUMO

Temperature changes in cells are generally accompanied by physiological processes. Cellular temperature measurements can provide important information to fully understand cellular mechanisms. However, temperature measurements with conventional methods, such as fluorescent polymeric thermometers and thermocouples, have limitations of low sensitivity or cell state disturbance. We developed a microfluidic chip integrating a high-precision platinum (Pt) thermo-sensor that can culture cells and monitor the cellular temperature in situ. During detection, a constant temperature system with a stability of 0.015 °C was applied. The temperature coefficient of resistance of the Pt thermo-sensor was 2090 ppm/°C, giving a temperature resolution of the sensor of less than 0.008 °C. This microchip showed a good linear correlation between the temperature and resistance of the Pt sensor at 20-40 °C (R2 = 0.999). Lung and liver cancer cells on the microchip grew normally and continuously. The maximum temperature fluctuation of H1975 (0.924 °C) was larger than that of HepG2 (0.250 °C). However, the temperature of adherent HepG2 cells changed over time, showing susceptibility to the environment most of the time compared to H1975. Moreover, the temperature increment of non-cancerous cells, such as hepatic stellate cells, was monitored in response to the stimulus of paraformaldehyde, showing the process of cell death. Therefore, this thermometric microchip integrated with cell culture could be a non-disposable and label-free tool for monitoring cellular temperature applied to the study of physiology and pathology.


Assuntos
Neoplasias , Fenômenos Fisiológicos , Termometria , Humanos , Microfluídica , Termômetros
5.
ACS Biomater Sci Eng ; 7(3): 1216-1229, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33560819

RESUMO

Although gene therapy targeting the α-synuclein gene (SNCA) has achieved outstanding results in the treatment of Parkinson's disease (PD), the lack of a suitable gene delivery system and inadequate therapeutic effects remains a tremendous obstacle for RNAi therapy. Here, a degradable nano-MgO micelle composite (MgO(pDNA)-INS-Plu-mRNA-NGF) with double interference (mediated by RNAi and α-synuclein (α-syn)-targeted mRNA) was constructed. Binding mRNA treatment significantly increased the inhibitory effect compared to the reduction of α-syn expression by RNAi alone. Moreover, the cell experiments demonstrated that the viability of the PD cell model can be significantly improved by nano-MgO micelle composite treatment. More importantly, the composite has the ability to penetrate the blood brain barrier and deliver genes and mRNA to neurons through endocytosis mediated by the nerve growth factor and its receptors, thus significantly downregulating the expression of α-syn in the PD mice model without causing damage to other major organs. Overall, this work provides a novel insight into the design of biomaterials for gene therapy for PD.


Assuntos
Doença de Parkinson , Animais , Camundongos , Micelas , Neurônios/metabolismo , Doença de Parkinson/terapia , Interferência de RNA , alfa-Sinucleína/genética
6.
Polymers (Basel) ; 11(12)2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31847369

RESUMO

Although asphalt-aggregate bonding provides contacting strength for hot mix asphalt (HMA), it is still ignorant in dynamic shear test, due to the only use of metal parallel plate. Modified parallel plates cored from different types of aggregate were provided to simulate aggregate-asphalt-aggregate (AAA) sandwich in HMA, aiming at the comprehensive interpretation on bonding's influence. This study began with an experimental design, aggregate plates, and joint clamps were processed to be installed into the rheometer. Aggregate type and loading conditions were set as essential variables. Subsequently, microscopic tests were utilized to obtain chemical components of aggregate, micro morphology of interface, and roughness of plates. The shearing tests for poly (styrene-butadiene-styrene)-modified asphalt were conducted in bonding with aggregate plates. Meanwhile, contrasting groups adopting metal plates followed the same experimental procedures. The results indicate that the influence of aggregate type on binder's rheological characteristics is dependent on the experimental variables, and microscopic characteristics and component differences should be taken into consideration when selecting aggregates in designing asphalt mixtures.

7.
Polymers (Basel) ; 11(8)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370317

RESUMO

Asphalt fine aggregate matrix (FAM) is a predominant component directly related to field performances of hot asphalt mix (HMA), it is necessary to investigate material properties of FAM. Prior to preparing FAM specimens, the asphalt content was calculated by keeping the filler-bitumen (FB) ratio the same as in the corresponding HMA. A non-destructive fabrication method instead of coring and cutting methods was developed to compact FAM cylinders, and the joint base was designed to be concentric with the loading axis of testing system. Rheological responses of FAM were studied using the dynamic shear rheometer (DSR). Two repeated tests prove that the FAM compactor and the jointed base meet the requirement of data validation. Results show that rheological performances of FAM are significantly affected by asphalt content, gradation, air void content, and testing frequency. Air void is concluded to be the decisive factor which influences the stability of FAM, and the fiber is demonstrated to play a role on enhancing the flow resistance of FAM-F even though with the richest asphalt content.

8.
Materials (Basel) ; 12(10)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137786

RESUMO

Compaction is the most critical stage during pavement construction, but the real-time rheological behavior in the compaction process of hot mix asphalt has not received enough attention. Rheological properties directly reflect the of mixture performance, the intrinsic directly reflects the influencing factors of compaction, and the pavement compactness and service life. Therefore, it is important to interpret the rheological properties of the asphalt mixture during the compaction process. In this paper, the improved Nishihara model was used to study the viscoelastic-plastic properties of the hot mix asphalt in the compaction process. Firstly, the improved Nishihara model was briefly introduced. Subsequently, the stress and strain correlation curves are obtained by the MTS (Material Testing System) compaction test, and the strain-time curve is fitted to determine the model parameter values. Finally, the parameters are substituted into the constitutive equation to obtain the strain-time curve and compared it with the test curve. The results show that the improved Nishihara model effectively depicts the real time behavior of the asphalt mixture in the compaction progress. The viscos and plastic parameters present certain differences, which reflects that the gradation and temperature have certain influence on the compaction characteristics of the mixture.

9.
Nanomedicine ; 14(4): 1123-1136, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29474924

RESUMO

Parkinson's disease (PD) is second most common neurodegenerative disorder worldwide. Although drugs and surgery can relieve the symptoms of PD, these therapies are incapable of fundamentally treating the disease. For PD patients, over-expression of α-synuclein (SNCA) leads to the death of dopaminergic neurons. This process can be prevented by suppressing SNCA over-expression through RNA interference. Here, we successfully synthesized gold nanoparticles (GNP) composites (CTS@GNP-pDNA-NGF) via the combination of electrostatic adsorption and photochemical immobilization, which could load plasmid DNA (pDNA) and target specific cell types. GNP was transfected into cells via endocytosis to inhibiting the apoptosis of PC12 cells and dopaminergic neurons. Simultaneously, GNP composites are also used in PD models in vivo, and it can successfully cross the blood-brain barrier by contents of GNP in the mice brain. In general, all the works demonstrated that GNP composites have good therapeutic effects for PD models in vitro and in vivo.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Animais , Humanos , Camundongos , Fator de Crescimento Neural/química , Doença de Parkinson/metabolismo , Plasmídeos/genética
10.
J Control Release ; 271: 31-44, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29274436

RESUMO

Oral drug delivery has attracted substantial attention due to its advantages over other administration routes. Bacillus spores, as oral probiotic agents, are applied widely. In this paper, a novel Bacillus spore-based oral colon targeted carrier loading curcumin was developed for colon cancer treatment. Curcumin was linked covalently with the outer coat of Bacillus spore and folate, respectively (SPORE-CUR-FA). Bacillus spores are capable of delivering drugs to the colon area through gastric barrier, taking the advantage of its tolerance to the harsh conditions and disintegration of the outer coat of spores after germination in the colon. The drug release in vitro and in vivo of SPORE-CUR-FA was investigated. Results showed that SPORE-CUR-FA had the characteristics of colon-targeted drug release. Pharmacokinetic studies confirmed that Bacillus spore-based carriers could efficiently improve the oral bioavailability of curcumin. In vitro and in vivo anti-tumor studies showed that SPORE-CUR-FA had substantial ability for inhibiting colon cancer cells. These findings suggest that this Bacillus spore-based oral drug delivery system has a great potential for the treatment of colon cancer.


Assuntos
Antineoplásicos/administração & dosagem , Bacillus coagulans , Neoplasias do Colo/tratamento farmacológico , Curcumina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Ácido Fólico/administração & dosagem , Esporos Bacterianos , Administração Oral , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Curcumina/química , Curcumina/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Ácido Fólico/química , Ácido Fólico/farmacocinética , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Ratos Sprague-Dawley
11.
Biomacromolecules ; 19(1): 31-41, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29172501

RESUMO

Photodynamic therapy (PDT), combining the laser and photosensitizers to kill tumor cells, has the potential to address many current medical requirements. In this study, magnetic Fe3O4 nanoparticles were first employed as cores and modified with oleic acid (OA) and 3-triethoxysilyl-1-propanamine. Then, the photosensitizers phycocyanin (PC) and hematoporphyrin monomethyl ether (HMME), which might be able to stimulate the cell release of reactive oxygen species after the irradiation of a near-infrared (NIR) laser, were grafted on the surface of such nanoparticles. Our results revealed the high-efficiency inhibition of breast cancer MCF-7 cells growing upon near-infrared irradiation both in vitro and in vivo. Furthermore, it was the synergy between the natural photosensitizers PC and the synthetic photosensitizers HMME that deeply influenced such inhibition compared to the groups that used either of these medicines alone. To utilize the combination of different photosensitive agents, our study thus provides a new strategy for breast cancer treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Hematoporfirinas/uso terapêutico , Nanopartículas de Magnetita/química , Fármacos Fotossensibilizantes/química , Ficocianina/uso terapêutico , Animais , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Feminino , Hematoporfirinas/administração & dosagem , Hematoporfirinas/farmacologia , Hematoporfirinas/toxicidade , Humanos , Raios Infravermelhos , Células MCF-7 , Nanopartículas de Magnetita/toxicidade , Camundongos Endogâmicos BALB C , Fotoquimioterapia , Ficocianina/administração & dosagem , Ficocianina/farmacologia , Ficocianina/toxicidade
12.
J Mater Chem B ; 5(30): 6016-6026, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32264358

RESUMO

Cordycepin has been successfully used as a natural anti-cancer drug, but it is rapidly metabolized in vivo. Nanoencapsulation is thus a promising method to improve its bioavailability. In this study, we adopted a green synthesis process to develop novel self-assembling phycocyanin-dextran-cordycepin (Phy-Dex-Cord) micelles for efficient cordycepin encapsulation and delivery. We first used the Maillard reaction method to graft dextran onto phycocyanin, forming a phycocyanin-dextran complex. Through the self-assembly of the cordycepin parcel to the phycocyanin-dextran complex, the micelles were formed. Their physical and chemical properties and characterization results showed that Phy-Dex-Cord micelles have a spherical shape and consistent size distribution of about 60 nm. In addition, anti-cancer activities in vitro and in vivo revealed that the Phy-Dex-Cord micelles have a comparable or even stronger inhibitory effect against C6 cells than do free cordycepin and free phycocyanin and no side effects.

13.
Adv Healthc Mater ; 5(18): 2413-26, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27385628

RESUMO

Synthesis of artificial and functional structures for bone tissue engineering has been well recognized but the associated cell senescence issue remains much less concerned so far. In this work, surface-modified polycaprolactone-polylactic acid scaffolds using self-assembled heterojunction carbon nanotubes (sh-CNTs) combined with insulin-like growth factor-1 are synthesized and a series of structural and biological characterizations are carried out, with particular attention to cell senescence mechanism. It is revealed that the modified scaffolds can up-regulate the expressions of alkaline phosphates and bone morphogenetic proteins while down-regulate the expressions of senescence-related proteins in mesenchymal stem cells, demonstrating the highly preferred anti-senescence functionality of the sh-CNTs modified scaffolds in bone tissue engineering. Furthermore, it is also found that with sh-CNTs, scaffolds can accelerate bone healing with extremely low toxicity in vivo.


Assuntos
Senescência Celular , Fator de Crescimento Insulin-Like I/química , Células-Tronco Mesenquimais/metabolismo , Nanotubos de Carbono/química , Poliésteres/química , Animais , Linhagem Celular , Proteínas Imobilizadas/química , Células-Tronco Mesenquimais/citologia , Ratos
14.
Colloids Surf B Biointerfaces ; 145: 104-113, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27137809

RESUMO

We developed a biomaterial by photo-immobilizing interferon-α (IFN-α) on the surface of latex condom films for the prevention and treatment of cervicitis, cervical cancers and diseases caused by cervical virus. The IFN-α modification by photoactive N-(4-azidobenzoyloxy) succinimide was characterized on a nano-scale by spectroscopy analysis and micro morphology. The anti-bacterial, anti-cancer, and anti-viral effects of the modified bioactive latex films were evaluated by antibacterial susceptibility testing, Gram staining, flow cytometry, immunofluorescence, and Western blotting. Our results showed that the photo-immobilized IFN-α latex films effectively inhibited the growth of both Neisseria gonorrhoeae and human cervical cancer HeLa cells. Moreover, the expression of anti-viral proteins, including P56, MxA, and 2', 5'-OAS, in the human cervical epithelial cell line NC104 was significantly increased by photo-immobilized IFN-α latex films. Taken together, these results suggest that photo-immobilized IFN-α latex films may have therapeutic effects against cervicitis, cervical cancers, and cervical virus.


Assuntos
Interferon-alfa/química , Membranas Artificiais , Proliferação de Células/efeitos dos fármacos , Células HeLa , Humanos , Interferon-alfa/farmacologia , Látex/química , Neisseria gonorrhoeae/efeitos dos fármacos
15.
Carbohydr Polym ; 139: 50-60, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-26794946

RESUMO

The destruction of PVC cables by termites is a continuing and long-standing problem, which can lead to power leakage and power cut. Given the environmental demerits of insecticide overuse, alternative methods of addressing this problem are a highly desirable goal. In this study, we used photo-immobilization to develop a chitosan carrier system to help bifenthrin immobilize on the surface of the PVC substrate. The immobilization was analyzed using nuclear magnetic resonance (NMR), UV absorption, reverse-phase high-performance liquid chromatography (RP-HPLC), Raman absorption spectroscopy, and thermal gravimetric analysis (TGA). The surface structure and biological activity of the embedded and immobilized bifenthrin were examined using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photon-electron spectroscopy (XPS). Its efficacy was assessed in pest experiments. The results indicate a successful embedding and immobilization of bifenthrin. Furthermore, the chemical bonding network between AzPhchitosan, bifenthrin, and PVC is stable, guaranteeing no environmental release of bifenthrin, and also providing more efficacious protection against termites. The evidence suggests that this photo-immobilization of bifenthrin-embedded chitosan on the surface of PVC substrates is a novel and environmentally friendly technique for termite control. This paper also reports a modification of chitosan with respect to its novel application in environmental protection.


Assuntos
Azidas/química , Quitosana/química , Reagentes de Ligações Cruzadas/química , Inseticidas/química , Cloreto de Polivinila/química , Piretrinas/química , Animais , Equipamentos e Provisões Elétricas , Controle de Insetos/métodos , Isópteros , Processos Fotoquímicos , Raios Ultravioleta
16.
Beilstein J Org Chem ; 10: 287-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24605149

RESUMO

The three-component reactions of aldehydes, electron deficient alkynes and ureas/thioureas have been smoothly performed to yield a class of unprecedented 3,4-dihydropyrimidinones and thiones (DHPMs). The reactions are initiated by the key transformation of an enamine-type activation involving the addition of a secondary amine to an alkyne, which enables the subsequent incorporation of aldehydes and ureas/thioureas. This protocol tolerates a broad range of aryl- or alkylaldehydes, N-substituted and unsubstituted ureas/thioureas and alkynes to yield the corresponding DHPMs with specific regioselectivity.

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