Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 89
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Adv Healthc Mater ; 13(5): e2302495, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056018

RESUMO

Emerging research suggests that mitochondrial DNA is a potential target for cancer treatment. However, achieving precise delivery of deoxyribozymes (DNAzymes) and combining photodynamic therapy (PDT) and DNAzyme-based gene silencing together for enhancing mitochondrial gene-photodynamic synergistic therapy remains challenging. Accordingly, herein, intelligent supramolecular nanomicelles are constructed by encapsulating a DNAzyme into a photodynamic O2 economizer for mitochondrial NO gas-enhanced synergistic gene-photodynamic therapy. The designed nanomicelles demonstrate sensitive acid- and red-light sequence-activated behaviors. After entering the cancer cells and targeting the mitochondria, these micelles will disintegrate and release the DNAzyme and Mn (II) porphyrin in the tumor microenvironment. Mn (II) porphyrin acts as a DNAzyme cofactor to activate the DNAzyme for the cleavage reaction. Subsequently, the NO-carrying donor is decomposed under red light irradiation to generate NO that inhibits cellular respiration, facilitating the conversion of more O2 into singlet oxygen (1 O2 ) in the tumor cells, thereby significantly enhancing the efficacy of PDT. In vitro and in vivo experiments reveal that the proposed system can efficiently target mitochondria and exhibits considerable antitumor effects with negligible systemic toxicity. Thus, this study provides a useful conditional platform for the precise delivery of DNAzymes and a novel strategy for activatable NO gas-enhanced mitochondrial gene-photodynamic therapy.


Assuntos
DNA Catalítico , Nanopartículas , Fotoquimioterapia , Porfirinas , Genes Mitocondriais , Oxigênio Singlete , Fármacos Fotossensibilizantes/farmacologia , Linhagem Celular Tumoral
2.
Angew Chem Int Ed Engl ; 63(1): e202316384, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38009454

RESUMO

Photocatalytic nitrogen fixation using solar illumination under ambient conditions is a promising strategy for production of the indispensable chemical NH3 . However, due to the catalyst's limitations in solar energy utilization, loss of hot electrons during transfer, and low nitrogen adsorption and activation capacity, the unsatisfactory solar-to-chemical conversion (SCC) efficiencies of most photocatalysts limit their practical applications. Herein, cerium oxide nanosheets with abundant strain-VO defects were anchored on Au hollow nanomushroom through atomically sharp interfaces to construct a novel semiconductor/plasmonic metal hollow nanomushroom-like heterostructure (denoted cerium oxide-AD/Au). Plasmonic Au extended the absorption of light from the visible to the second near-infrared region. The superior interface greatly enhanced the transfer efficiency of hot electrons. Abundant strain-VO defects induced by interfacial compressive strain promoted adsorption and in situ activation of nitrogen, and such synergistic promotion of strain and VO defects was further confirmed by density functional theory calculations. The judicious structural and defect engineering co-promoted the efficient nitrogen photofixation of the cerium oxide-AD/Au heterostructures with a SCC efficiency of 0.1 % under simulated AM 1.5G solar illumination, which is comparable to the average solar-to-biomass conversion efficiency of natural photosynthesis by typical plants, thus exhibiting significant potential as a new candidate for artificial photosynthesis.

3.
Adv Mater ; 35(38): e2302839, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37391877

RESUMO

Dual-interface modulation including buried interface as well as the top surface has recently been proven to be crucial for obtaining high photovoltaic performance in lead halide perovskite solar cells (PSCs). Herein, for the first time, the strategy of using functional covalent organic frameworks (COFs), namely HS-COFs for dual-interface modulation, is reported to further understand its intrinsic mechanisms in optimizing the bottom and top surfaces. Specifically, the buried HS-COFs layer can enhance the resistance against ultraviolet radiation, and more importantly, release the tensile strain, which is beneficial for enhancing device stability and improving the order of perovskite crystal growth. Furthermore, the detailed characterization results reveal that the HS-COFs on the top surface can effectively passivate the surface defects and suppress non-radiation recombination, as well as optimize the crystallization and growth of the perovskite film. Benefiting from the synergistic effects, the dual-interface modified devices deliver champion efficiencies of 24.26% and 21.30% for 0.0725 cm2 and 1 cm2 -sized devices, respectively. Moreover, they retain 88% and 84% of their initial efficiencies after aging for 2000 h under the ambient conditions (25 °C, relative humidity: 35-45%) and a nitrogen atmosphere with heating at 65 °C, respectively.

4.
Nanoscale Adv ; 5(13): 3527-3535, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37383071

RESUMO

Coordination polymers (CPs) have emerged as promising candidates for photocatalytic H2 production owing to their structural tailorability and functional diversity. However, the development of CPs with high energy transfer efficiency for highly efficient photocatalytic H2 production in a wide pH range still faces many challenges. Here we constructed a novel tube-like Pd(ii) coordination polymer with well-distributed Pd nanoparticles (denoted as Pd/Pd(ii)CPs) based on the coordination assembly of rhodamine 6G and Pd(ii) ions and further photo-reduction under visible light irradiation. Both the Br- ion and double solvent play a key role in forming the hollow superstructures. The resulting tube-like Pd/Pd(ii)CPs exhibit high stability in aqueous solution with the pH range from 3 to 14 due to the high Gibbs free energies of protonation and deprotonation, which provides the feasibility of photocatalytic hydrogen generation in a wide pH range. Electromagnetic field calculations showed that the tube-like Pd/Pd(ii)CPs have a good confinement effect on light. Therefore, the H2 evolution rate could reach 112.3 mmol h-1 g-1 at pH 13 under visible light irradiation, which is far superior to those of reported coordination polymer-based photocatalysts. Moreover, such Pd/Pd(ii)CPs could also reach a H2 production rate of 37.8 mmol h-1 g-1 in seawater under visible light with low optical density (40 mW cm-2) close to morning or cloudy sunlight. The above unique characteristics make the Pd/Pd(ii)CPs possess great potential for practical applications.

5.
J Fluoresc ; 33(6): 2241-2252, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37010649

RESUMO

Cyclodextrin (CD) is an important guest material owing to the water solubility and biocompatibility. In the paper, an organic small molecule was synthesized. According to supramolecular self-assembly, the organic molecule was bounded to the cavity of Poly ß-cyclodextrin, which was characterized by IR, SEM and TEM et al. After self-assembly interaction, the morphology has changed obviously comparing with precursors. Simultaneously, the supramolecular self-assembly complex exhibited good water solubility. Moreover, By Gaussian calculation, the high binding activity between organic molecule and cyclodextrin was confirmed. By fluorescence investigation, the supramolecular system showed high fluorescence sensing activity for Zn2+ in pure water environment, which could track the dynamic change of Zn2+ in organisms. In addition, the supramolecular system exhibited low cytotoxicity. The work provided an interesting pathway for constructing water-soluble and low cytotoxic fluorescence sensor for Zn2+.

6.
Chem Sci ; 13(47): 14141-14150, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36540813

RESUMO

Perovskite quantum dots (QDs) are promising as representative candidates to construct next-generation superior artificial light-harvesting systems (ALHSs). However, their high sensitivity to external environments, especially to water, imposes a stringent limitation for their actual implementation. Herein, by interface engineering and encapsulation with natural palygorskite (PAL), a water-resistant light-harvesting CsPbBr3@PAL antenna was prepared. Molecular dynamics simulations further confirm a significant shielding protection of the PAL matrix to CsPbBr3, facilitating exceptional stability of the CsPbBr3@PAL antenna when exposed to air for 10 months, to 150 °C thermal stress, and even to water for more than 30 days, respectively. Furthermore, as a result of in situ encapsulation of the PAL matrix and defect passivation caused by H-bonding and coordination-bonding interaction, the CsPbBr3@PAL antenna in water shows a substantially enhanced photoluminescence quantum yield (36.2%) and longer lifetime. After sequentially assembling Eosin Y and Rose Bengal in the pores of the PAL matrix, RB-ESY-CsPbBr3@PAL with a sequential two-step efficient Förster resonance energy transfer process exhibited extremely enhanced photocatalytic activity toward Friedel-Crafts alkylation reactions in aqueous solution, 2.5-fold higher than that of corresponding ESY/RB. Our work provides a feasible strategy for the exploitation of ultra-stable halide perovskite-based ALHSs in aqueous media for solar-energy conversion.

7.
Anal Chem ; 94(33): 11573-11581, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35943780

RESUMO

Energy deprivation and reduced levels of hydrogen sulfide (H2S) in the brain is closely associated with Alzheimer's disease (AD). However, there is currently no fluorescent probe for precise exploration of both H2S and adenosine triphosphate (ATP) to directly demonstrate their relationship and their dynamic pattern changes. Herein, we developed a two-photon fluorescent probe, named AD-3, to simultaneously image endogenous H2S and ATP from two emission channels of fluorescent signals in live rat brains with AD. The probe achieved excellent selectivity and good detection linearity for H2S in the 0-100 µM concentration range and ATP in the 2-5 mM concentration range, respectively, with a detection limit of 0.19 µM for H2S and 0.01 mM for ATP. Fluorescence imaging in live cells reveals that such probe could successfully apply for simultaneous imaging and accurate quantification of H2S and ATP in neuronal cells. Further using real-time quantitative polymerase chain reaction and Western blots, we confirmed that H2S regulates ATP synthesis by acting on cytochrome C, cytochrome oxidase subunit 3 of complex IV, and protein 6 of complex I in the mitochondrial respiratory chain. Subsequently, we constructed a high-throughput screening platform based on AD-3 probe to rapidly screen the potential anti-AD drugs to control glutamate-stimulated oxidative stress associated with abnormal H2S and ATP levels. Significantly, AD-3 probe was found capable of imaging of H2S and ATP in APP/PS1 mice, and the concentration of H2S and ATP in the AD mouse brain was found to be lower than that in wild-type mice.


Assuntos
Doença de Alzheimer , Sulfeto de Hidrogênio , Trifosfato de Adenosina , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Animais , Corantes Fluorescentes , Ácido Glutâmico , Células HeLa , Humanos , Sulfeto de Hidrogênio/análise , Camundongos , Fótons , Ratos
8.
RSC Adv ; 12(3): 1258-1264, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35425208

RESUMO

As a class of important carbon nanomaterial, carbonized polymer dots (CPDs), also called carbon dots (CDs), have aroused wide interest owing to their unique water solubility, fluorescence properties, and rich surface functional groups. However, the directional tuning of the fluorescence properties of CPDs remains incomplete because of the influence of many factors like diameter, solvent and surface groups. Particularly, most carbonized polymer dots are synthesized in a neutral pH environment. Herein, by modulating the pH (strongly acidic or alkaline) of dextrin water solution, bicolor fluorescence emission (blue and yellow) CPDs were prepared by a hydrothermal reaction. Through systematic characterization, it was found that the different fluorescence properties are regulated by the diameters and surface groups of the carbon cores. Simultaneously, the pH value affected the nucleation process. Based on the excellent fluorescence properties, cell fluorescence imaging and cytotoxicity were tested. The bicolor fluorescence CPDs obtained by tuning the pH provide an important theoretical basis for the design of broadband CPDs.

9.
Anal Chem ; 93(42): 14307-14316, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34641676

RESUMO

Quantitative detection of cancer cells using portable devices is promising for the development of simple, fast, and point-of-care cancer diagnostic techniques. However, how to further amplify the detection signal to improve the sensitivity and accuracy of detecting cancer cells by portable devices remains a challenge. To solve the problem, we, for the first time, synthesized folic-acid-conjugated Au nanoframes (FA-Au NFs) with amplification of pressure and temperature signals for highly sensitive and accurate detection of cancer cells by portable pressure meters and thermometers. The resulting Au NFs exhibit excellent near-infrared (NIR) photothermal performance and catalase activity, which can promote the decomposition of NH4HCO3 and H2O2 to generate corresponding gases (CO2, NH3, and O2), thereby synergistically amplifying pressure signals in a closed reaction vessel. At the same time, Au NFs with excellent peroxidase-like activity can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce TMB oxide (oxTMB) with a strong photothermal effect, thereby cooperating with Au NFs to amplify the photothermal signal. In the presence of cancer cells with overexpressing folate receptors (FRs), the molecular recognition signals between FA and FR can be converted into amplified pressure and temperature signals, which can be easily read by portable pressure meters and thermometers, respectively. The detection limits for cancer cells using pressure meters and thermometers are 6 and 5 cells/mL, respectively, which are better than other reported methods. Moreover, such Au NFs can improve tumor hypoxia by catalyzing the decomposition of H2O2 to produce O2 and perform photothermal therapy of cancer. Together, our work provides new insight into the application of Au NFs to develop a dual-signal sensing platform with amplification of pressure and temperature signals for portable and ultrasensitive detection of cancer cells as well as personalized cancer therapy.


Assuntos
Ouro , Neoplasias , Catálise , Peróxido de Hidrogênio , Neoplasias/terapia , Terapia Fototérmica , Temperatura
10.
ACS Appl Mater Interfaces ; 13(39): 46451-46463, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34570459

RESUMO

Light-driven endogenous water oxidation has been considered as an attractive and desirable way to obtain O2 and reactive oxygen species (ROS) in the hypoxic tumor microenvironment. However, the use of a second near-infrared (NIR-II) light to achieve endogenous H2O oxidation to alleviate tumor hypoxia and realize deep hypoxic tumor phototherapy is still a challenge. Herein, novel plasmonic Ag-AgCl@Au core-shell nanomushrooms (NMs) were synthesized by the selective photodeposition of plasmonic Au at the bulge sites of the Ag-AgCl nanocubes (NCs) under visible light irradiation. Upon NIR-II light irradiation, the resulting Ag-AgCl@Au NMs could oxidize endogenous H2O to produce O2 to alleviate tumor hypoxia. Almost synchronously, O2 could react with electrons on the conduction band of the AgCl core to generate superoxide radicals (O2•-)for photodynamic therapy. Moreover, Ag-AgCl@Au NMs with an excellent photothermal performance could further promote the phototherapy effect. In vitro and in vivo experimental results show that the resulting Ag-AgCl@Au NMs could significantly improve tumor hypoxia and enhance phototherapy against a hypoxic tumor. The present study provides a new strategy to design H2O-activatable, O2- and ROS-evolving NIR II light-response nanoagents for the highly efficient and synergistic treatment of deep O2-deprived tumor tissue.


Assuntos
Antineoplásicos/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Hipóxia Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Catálise , Linhagem Celular Tumoral , Ouro/química , Ouro/efeitos da radiação , Ouro/uso terapêutico , Raios Infravermelhos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Camundongos Endogâmicos BALB C , Oxigênio/metabolismo , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Terapia Fototérmica , Prata/química , Prata/efeitos da radiação , Prata/uso terapêutico , Compostos de Prata/química , Compostos de Prata/efeitos da radiação , Compostos de Prata/uso terapêutico , Água/química
11.
Chem Commun (Camb) ; 57(74): 9434-9437, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528973

RESUMO

A near-infrared (NIR) emissive artificial light-harvesting system with two-step high-efficiency sequential resonance energy transfers was fabricated based on the in situ growth of MAPbBr3 quantum dots in the supramolecular self-assembly of a Zn(II) carboxyl-functionalized pillar[5]arene coordination polymer and two different fluorescent dyes, eosin Y and Nile blue. This system could realize NIR fluorescent imaging of the sweat pores of latent fingerprints, opening a new avenue to design perovskite-based NIR emitting artificial light-harvesting systems for third-level fingerprint imaging.


Assuntos
Compostos de Cálcio/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo , Imagem Óptica , Óxidos/metabolismo , Titânio/metabolismo , Compostos de Cálcio/química , Transferência de Energia , Corantes Fluorescentes/química , Raios Infravermelhos , Complexos de Proteínas Captadores de Luz/química , Estrutura Molecular , Óxidos/química , Tamanho da Partícula , Espectroscopia de Luz Próxima ao Infravermelho , Titânio/química
12.
Anal Chem ; 93(33): 11470-11478, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34379390

RESUMO

l-3,4-Dihydroxy-phenylalanine (l-DOPA) is the most effective drug for the treatment of Parkinson's disease, which plays a very important role in clinical and neurochemistry. However, how to achieve high-sensitivity recognition of l-DOPA still faces challenges. Here, a facile strategy is presented to construct nitrogen-doped chiral CuO/CoO nanofibers (N-CuO/CoO NFs) with nanozyme activity and electrochemiluminescence property, in which CuO/CoO NFs are used as the catalytic activity center and chiral cysteine (Cys) is used as the inducer of chiral recognition, for enantioselective catalysis and sensitive recognition of DOPA enantiomers. Notably, N doping not only enhances the enzyme-mimic activity of CuO/CoO NFs but also amplifies their electrochemiluminescence (ECL) signals in the presence of luminol. More importantly, in the presence of DOPA enantiomers, the d-cysteine (d-Cys)-modified N-CuO/CoO NFs exhibit different ECL performances; thus, d-Cys@N-CuO/CoO NFs could selectively distinguish and sensitively detect l-DOPA through ECL signals, and the detection limit is 0.29 nM for l-DOPA. In addition, it also showed good sensing performance for the determination of l-DOPA in fetal bovine serum. This is the first report on the detection of DOPA enantiomers based on an enhanced ECL strategy, providing a robust pathway for chiral discrimination and detection of chiral molecules.


Assuntos
Nanofibras , Fenilalanina , Cobre , Nitrogênio , Estereoisomerismo
13.
Biosens Bioelectron ; 190: 113417, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34134071

RESUMO

The development of highly sensitive and simple detection methods for cancer cells is an important challenge to achieve early cancer diagnosis and effective treatment. In this paper, folic acid (FA)-conjugated platinum (IV) methylene blue (MB) coordination polymers nanorods (denoted as FA-PtCPs NRs) were developed by the photochemical method. The structure of the PtCPs NRs was investigated using the meta-dynamics and genetic algorithms (MTD-GC) method, and it was found that the coordination bond was formed between platinum (IV) and N atoms of MB. The field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) indicated that the morphology of PtCPs NRs was rod-like. The resulting FA-PtCPs NRs was used for the specific and ultra-sensitive temperature detection of cancer cells based on PtCPs NRs as a signal trigger unit and FA as a target recognition tool. After three-step reaction, oxidized 3,3',5,5'-tetramethylbenzidine (ox-TMB) with photothermal effect was obtained. Under 660 nm laser irradiation, such detection platform can convert the molecular recognition signal between FA and folate receptor (FR) of cancer cells into readable temperature value, which can be directly read by an ordinary thermometer, with a detection limit as low as 2 cells/mL. In addition, FA-PtCPs NRs could be used as fluorescent probes for in-situ bioimaging. Therefore, this photothermal sensing platform has a broad prospect in the field of point-of-care detection of cancer cells.


Assuntos
Técnicas Biossensoriais , Nanotubos , Neoplasias , Ácido Fólico , Neoplasias/diagnóstico , Platina , Polímeros
14.
Small ; 17(24): e2100969, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33938137

RESUMO

Solar-driven evaporation is regarded as a sustainable wastewater treatment strategy for clean water recovery and salt condensation. However, achieving both high evaporation rate and long-term stability remain challenging due to poor thermal management and rapid salt accumulation and blocking. Here, a T-shape solar-driven evaporator, composed of a surface-carbonized longitudinal wood membrane (C-L-wood) is demonstrated as the top "" for solar harvesting/vapor generation/salt collection and another piece of natural L-wood as the support "" for brine transporting and thermally insulating. The horizontally aligned micro-channels of C-L-wood have a low perpendicular thermal conductivity and can effectively localize the thermal energy for rapid evaporation. Meanwhile, the brine is guided to transport from the support L-wood ("") to the centerline of the top evaporator and then toward the double edge (""), during which clean water is evaporated and salt is crystallized at the edge. The T-shape evaporator demonstrates a high evaporation rate of 2.43 kg m-2 h-1 under 1 sun irradiation, and is stable for 7 days of the outdoor operation, which simultaneously realizes clean water evaporation and salt collection (including Cu2+ , CrO42- , Co2+ ), and achieves zero-liquid discharge. Therefore, the T-shape design provides an effective strategy for high performance wastewater treatment.


Assuntos
Energia Solar , Purificação da Água , Luz Solar , Água , Madeira
15.
Adv Healthc Mater ; 10(7): e2001728, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33305535

RESUMO

Carbon monoxide (CO) as an emerging treatment holds great promise for inducing the apoptosis of cancer cells. Here coordination assembled strategy is first reported for synthesis of Cu(II)-flavone coordination polymer (NCu-FleCP) CO nanoprodrug that is stable in normal physiological conditions, and yet readily reduces to small size prodrug complex and releases CO on demand under glutathione (GSH) and near infrared (NIR) light. Specifically, after uptaking by cancer cells, local GSH attacked coordination bond within NCu-FleCP, resulting in the release of Cu(I) and free Fle. The CC bond of Fle is cleavage under NIR light to release CO for gas therapy, and Cu(I) reacts with local H2 O2 through Fenton like reaction to generate hydroxyl radicals (• OH) for chemodynamic therapy. Detailed in vitro and in vivo experiments demonstrate that the CO prodrug system in generating a sufficient quantity of CO and • OH offers remarkable destructive effects against cancer cells without causing toxicity to surrounding normal tissues. The study provides a solid foundation to develop smart coordination polymer CO prodrugs with on-demand CO release, enhanced permeability and retention effect, and biodegradability for multimodal synergistic therapy.


Assuntos
Neoplasias , Pró-Fármacos , Humanos , Raios Infravermelhos , Neoplasias/tratamento farmacológico , Polímeros , Pró-Fármacos/farmacologia , Microambiente Tumoral
16.
Sci Adv ; 6(48)2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33246959

RESUMO

Nanozymes as artificial enzymes that mimicked natural enzyme-like activities have received great attention in cancer therapy. However, it remains a great challenge to design nanozymes that precisely exert its activity in tumor without producing off-target toxicity to surrounding normal tissues. Here, we report a synergetic enhancement strategy through the combination between nanozyme and tumor vascular normalization to destruct tumors, which was based on tumor microenvironment (TME) "unlocking." This nanozyme that we developed not only has photothermal properties but also can produce reactive oxygen species efficiently under the stimulation of TME. Moreover, this nanozyme also showed remarkable imaging performance in fluorescence imaging in the second near-infrared region and magnetic resonance imaging for visualization tracing in vivo. The process of combination therapy showed remarkable therapeutic effect for breast cancer. This study provides a therapeutic strategy by the cooperation between multifunctional nanozyme and tumor vascular normalization for intensive combination therapy of breast cancer.


Assuntos
Neoplasias da Mama , Fotoquimioterapia , Neoplasias da Mama/tratamento farmacológico , Catálise , Terapia Combinada , Feminino , Humanos , Espécies Reativas de Oxigênio , Microambiente Tumoral
17.
ACS Appl Mater Interfaces ; 12(29): 32817-32826, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32603085

RESUMO

Water pollution arising from pharmaceuticals has raised great concerns about the potential risks for biosphere and human health. However, rapid and efficient removal of pharmaceutical contaminants from water remains challenging. Wood sawdust, a byproduct of the wood-processing industry, is an abundant, cost-effective, and sustainable material with a unique hierarchically porous microstructure. These features make wood sawdust quite interesting as a filtration material. Here, we report a novel cross-flow filtration composite based on ß-cyclodextrin-polymer-functionalized wood sawdust (ß-CD/WS) in which the pharmaceutical contaminant water flows through the sawn-off vessel channels and the micropores on the surface of the cell walls, generating the turbulence. Such water flow characteristics ensure full contact between pharmaceutical pollutants and ß-CD grafted on the cellulose backbone of wood sawdust, thereby enhancing the water treatment efficiency. Consequently, the ß-CD/WS filter device shows a high removal efficiency of over 97.5% within 90 s for various pharmaceutical contaminants including propranolol, amitriptyline, chlortetracycline, diclofenac, and levofloxacin, and a high saturation uptake capacity of 170, 156, 257, 159, and 185 mg g-1, respectively. The high-performance wood-sawdust-based cross-flow filtration opens new avenues for solving the global water pollution issues, especially those caused by pharmaceutical contaminants.


Assuntos
Celulose/química , Ciclodextrinas/química , Poluentes Químicos da Água/isolamento & purificação , Madeira/química , Amitriptilina/química , Amitriptilina/isolamento & purificação , Biomassa , Celulose/síntese química , Clortetraciclina/química , Clortetraciclina/isolamento & purificação , Ciclodextrinas/síntese química , Diclofenaco/química , Diclofenaco/isolamento & purificação , Contaminação de Medicamentos , Levofloxacino/química , Levofloxacino/isolamento & purificação , Tamanho da Partícula , Propranolol/química , Propranolol/isolamento & purificação , Propriedades de Superfície , Poluentes Químicos da Água/química
18.
Nanoscale ; 12(10): 6195-6203, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32133481

RESUMO

Vertical heterojunctions of two-dimensional (2D) semiconducting materials have attracted more and more research interest recently due to their unique optical, electrical, and catalytic properties and potential applications. Although great progress has been made, vertical integration of the layered materials formed by 2D semiconductor nanosheets and 2D plasmatic metal nanosheets remains a huge challenge. Here, we demonstrate for the first time a solution-phase growth of vertical plasmatic metal-semiconductor heterostructures in which aligned NiCo2O4 nanosheet arrays vertically grow on a single Au nanosheet, forming vertically aligned NiCo2O4-Au-NiCo2O4 sandwich-type heterojunctions with hierarchical open channels. Such vertical NiCo2O4-Au-NiCo2O4 heterojunctions can effectively promote the separation and transfer of a photoinduced charge. Density functional theory (DFT) studies and time-resolved transient absorption spectroscopy show that electrons transfer from NiCo2O4 to Au, and the formation of the heterojunction weakens the H-O bond of H2O. Due to the unique structure and superiority of the component, the vertical NiCo2O4-Au-NiCo2O4 heterojunctions exhibit significant activity with an O2 production rate of up to 33 µmol h-1 and long-term stability for photocatalytic water oxidation. We calculated the apparent quantum efficiency (AQE) to be 21.9% for NiCo2O4-Au-NiCo2O4 heterojunctions at the wavelength λ = 450 ± 10 nm, which is higher than that of NiCo2O4 nanosheets (10.9%), Au nanosheets (0.96%) and other photocatalysts. The present study paves the way for the controlled synthesis of novel vertical heterojunctions based on 2D semiconductor nanosheets and 2D metal nanosheets for efficient photocatalysis.

19.
ACS Appl Mater Interfaces ; 12(13): 15002-15011, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32149496

RESUMO

Heavy metal pollution is a severe problem worldwide. Great efforts have been devoted in developing effective and eco-friendly ways to remove heavy metal ions from contaminated water. However, challenges remain in terms of the high cost, the complex preparation processes required, low efficiency, and difficulties in scaling-up. Here, we report a sulfhydryl-functionalized wood (SH-wood) membrane featuring three-dimensional mesoporous and low-tortuosity lumens, which serve as multisite metal traps to achieve highly efficient heavy metal ion removal from wastewater. Benefiting from the unique microstructure of wood, the resulting membrane exhibits a high saturation uptake capacity of 169.5, 384.1, 593.9, and 710.0 mg·g-1 for Cu2+, Pb2+, Cd2+, and Hg2+ ions, respectively. Meanwhile, the SH-wood membrane can be easily regenerated at least eight times without apparent performance loss. Furthermore, stacking multilayers of the SH-wood filter is designed. Because of its high yet universal heavy metal ion absorbance capability, the multilayer SH-wood filter can effectively remove diverse heavy metal ions from real contaminated water, meeting the WHO standards while also displaying a high flux rate of 1.3 × 103 L·m-2·h-1. Our work presents a promising strategy for the scalable and highly efficient removal of heavy metal ions from sewage for environmental remediation.


Assuntos
Metais Pesados/isolamento & purificação , Compostos de Sulfidrila/química , Poluentes Químicos da Água/química , Madeira/química , Adsorção , Celulose/química , Cobre/química , Cobre/isolamento & purificação , Recuperação e Remediação Ambiental/métodos , Íons/química , Cinética , Metais Pesados/química , Porosidade , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação
20.
Anal Chem ; 92(6): 4672-4680, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32090547

RESUMO

New methods for portable detection of arsenate are still in urgent need. Herein, we explored a simple but sensitive thermometric strategy for arsenate determination without complex instruments and skilled technicians. Cobalt oxyhydroxide (CoOOH) nanoflakes, can ingeniously decompose hydrogen peroxide into oxygen in a sealed reaction vessel, accompanied by marked pressure and significant temperature increase due to the exothermic reaction effect (ΔH = -98.2 kJ/mol). The increased pressure then compelled a certain amount of H2O overflowing from the drainage device into another vessel, leading to a significant temperature decrease due to the preloaded ammonium nitrate (NH4NO3) and its good dissolution endothermic effect (ΔH = 25.4 kJ/mol). In the presence of arsenate, the catalytic activity of CoOOH nanoflakes for H2O2 decomposition was inhibited dramatically, resulting in an obvious decrease of the pressure, weighting water and temperature response. The two temperature responses with increasing and decreasing feature were easily measured through a common thermometer, and exhibited an effective signaling amplification via coupling both "signal-on" and "signal-off" temperature readout elements. The obtained dual superimposing temperature readout exhibits a good linear with the concentration of arsenate with a lower detection limit (51 nM, 3.8 ppb). Compared to the inductively coupled plasma mass spectrometry, this enhanced thermometric strategy provides a simple, rapid, convenient, low cost, and portable platform for sensing arsenate in real environmental water.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...