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1.
Chem Commun (Camb) ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39005066

RESUMO

Au@Ag core-shell composites were successfully fabricated on urchin-like covalent organic frameworks (COFs), providing a platform with numerous hot spots for the detection of two categories of emerging contaminants: sulfonamide antibiotics and nanoplastics, using surface-enhanced Raman spectroscopy (SERS). Au seeds (∼10 nm) were generated on the COFs, leveraging the reducing properties of the vinyl and imino groups within the framework. This ensured the growth of dense and uniformly distributed Ag nanoparticles. The COFs exceptionally large surface area (2324 m2 g-1) and high adsorption capacity, significantly contributed to the enrichment and detection of trace pollutants. As a result, using a portable Raman spectrometer, limits of detection of 0.008 µmol L-1 for sulfamethoxazole and 0.029 mg L-1 for polystyrene nanoplastics were achieved.

2.
Adv Mater ; : e2405399, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896104

RESUMO

The recovery of precious metals (PMs) from secondary resources has garnered significant attention due to environmental and economic considerations. Covalent organic frameworks (COFs) have emerged as promising adsorbents for this purpose, owing to their tunable pore size, facile functionalization, exceptional chemical stability, and large specific surface area. This review provides an overview of the latest research progress in utilizing COFs to recover PMs. Firstly, the design and synthesis strategies of chemically stable COF-based materials, including pristine COFs, functionalized COFs, and COF-based composites, are delineated. Furthermore, the application of COFs in the recovery of gold, silver, and platinum group elements is delved into, emphasizing their high adsorption capacity and selectivity as well as recycling ability. Additionally, various interaction mechanisms between COFs and PM ions are analyzed. Finally, the current challenges faced by COFs in the field of PM recovery are discussed, and potential directions for future development are proposed, including enhancing the recyclability and reusability of COF materials and realizing the high recovery of PMs from actual acidic wastewater. With the targeted development of COF-based materials, the recovery of PMs can be realized more economically and efficiently in the future.

3.
J Hazard Mater ; 467: 133764, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38354438

RESUMO

The extraction performance of materials is highly related to their physical structure. However, the precise impact of ordered pore structure in covalent organic frameworks (COFs) on extraction performance are still puzzling. To look insight into this, a series of COFs with varying degrees of ordered pore structures were prepared at room temperature by adjusting reaction time and their extraction efficiencies toward phenolic compounds were investigated. The experimental results revealed that the COF with a short range ordered pore structure exhibited a higher affinity for phenolic compounds along with a larger enrichment factor, while the COF with a long range ordered pore structure demonstrated faster extraction kinetics. The investigation into interaction mechanism revealed that the density of available sites is responsible for these differences. Taking COF-OMe-0.5 h as solid-phase microextraction fiber coating, a highly efficient and sensitive quantitative analysis method for phenolic compounds was established by combining it with gas chromatograph-mass spectrometer. The established method boasts high enrichment factors (7192-29440), wide linear ranges (2.0-10000 ng L-1), and low detection limits (0.24-0.54 ng L-1). This study provides a conceptual guide for constructing desirable COFs with controlled pore structures for specific applications.

4.
Anal Chim Acta ; 1287: 341953, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38182358

RESUMO

Solid-phase microextraction (SPME) is a green, environmentally friendly, and efficient technique for sample pre-treatment. Covalent organic frameworks (COFs), a class of porous materials formed by covalent bonds, have gained prominence owing to their remarkable attributes, including large specific surface area, tunable pore size, and robust thermal/chemical stability. These characteristics have made COFs highly appealing as potential coatings for SPME fiber over the past decades. In this review, various methods used to prepare SPME coatings based on COFs are presented. These methods encompass physical adhesion, sol-gel processes, in situ growth, and chemical cross-linking strategies. In addition, the applications of COF-based SPME coating fibers for the preconcentration of various targets in environmental, food, and biological samples are summarized. Moreover, not only their advantages but also the challenges they pose in practical applications are highlighted. By shedding light on these aspects, this review aims to contribute to the continued development and utilization of COF materials in the field of sample pretreatment.

5.
Parasit Vectors ; 16(1): 280, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580819

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is increasing worldwide. Although there is currently no completely curative treatment, helminthic therapy shows certain therapeutic potential for UC. Many studies have found that Trichinella spiralis (T.s) has a protective effect on UC, but the specific mechanism is still unclear. METHODS: Balb/c mice drank dextran sulfate sodium (DSS) to induce acute colitis and then were treated with T.s. In vitro experiments, the LPS combination with ATP was used to induce the pyroptosis model, followed by intervention with crude protein from T.s (T.s cp). Additionally, the pyroptosis agonist of NSC or the pyroptosis inhibitor vx-765 was added to intervene to explore the role of pyroptosis in DSS-induced acute colitis. The degree of pyroptosis was evaluated by western blot, qPCR and IHC, etc., in vivo and in vitro. RESULTS: T.s intervention significantly inhibited NLRP3 inflammasome activation and GSDMD-mediated pyroptosis by downregulating the expression of pyroptosis-related signatures in vitro (cellular inflammatory model) and in vivo (DSS-induced UC mice model). Furthermore, blockade of GSDMD-mediated pyroptosis by the caspase-1 inhibitor vx-765 has a similar therapeutic effect on DSS-induced UC mice with T.s intervention, thus indicating that T.s intervention alleviated DSS-induced UC in mice by inhibiting GSDMD-mediated pyroptosis. CONCLUSION: This study showed that T.s could alleviate the pathological severity UC via GSDMD-mediated pyroptosis, and it provides new insight into the mechanistic study and application of helminths in treating colitis.


Assuntos
Colite Ulcerativa , Colite , Gasderminas , Doenças Inflamatórias Intestinais , Trichinella spiralis , Animais , Camundongos , Colite/induzido quimicamente , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Piroptose
6.
ACS Nano ; 17(10): 8918-8934, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37131272

RESUMO

Hollow covalent organic frameworks (COFs) have gained significant attention because of their specific properties, including enhanced surface-to-volume ratio, large surface area, hierarchical structure, highly ordered nanostructures, and excellent chemical stability. These intrinsic characteristics endow hollow COFs with fascinating physicochemical properties and make them highly attractive for widespread applications, such as catalysis, energy storage, drug delivery, therapy, sensing, and environmental remediation. This review focuses on the recent developments in the synthesis of hollow COFs and their derivatives. In addition, their practical applications in various fields are summarized. Finally, challenges and future opportunities in terms of their synthetic methodologies and practical applications are discussed. Hollow COFs are expected to play an important role in the future of materials science.

7.
Chem Commun (Camb) ; 59(42): 6410-6413, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37158199

RESUMO

A new method was developed for the coagulation of arsenic with serpentine and Fe(II). Excellent removal efficiency (>99%) and satisfactory stability of the sediments were accomplished for As(V) and As(III). A mechanism study showed that hydroxyls generated by the surface hydrolysis of serpentine mediated active iron hydroxides for arsenic adsorption, while the Fe-As and Mg-As chemical interaction contributed to the arsenic stabilization.

8.
J Chromatogr A ; 1689: 463770, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36638587

RESUMO

The ubiquitous occurrence of nonsteroidal anti-inflammatory drugs (NSAIDs) in the environmental water system has drawn significant concerns due to their adverse effects. The accurate monitoring the content of them is of great significance but challenging in terms of the complex matrix and trace concentration. In this work, a porphyrin-based magnetic porous organic polymer composite (PM-POP) was prepared through a solvent-free synthetic method. Owing to the highly porous structure and strong affinities, the as-prepared PM-POP could be utilized as a highly efficient adsorbent for the magnetic solid phase extraction (MSPE) of NSAIDs. Combining with the high-performance liquid chromatography separation with ultraviolet detector (HPLC-UV), a sensitive analytical method was established, which exhibited wide linear ranges (0.1-400 µg/L) and large enrichment factors (EFs) (39.5-82.9 folds) along with good precision (intra-day RSD ≤ 4.9%) and repeatability (inter-day RSD ≤ 8.4%). Ultimately, it was applied to determinate trace NSAIDs in practical water samples successfully, demonstrating its good application prospect in environmental analysis.


Assuntos
Polímeros , Porfirinas , Polímeros/química , Água , Porosidade , Adsorção , Anti-Inflamatórios não Esteroides/análise , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Fenômenos Magnéticos
9.
Nanomaterials (Basel) ; 12(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36558229

RESUMO

In this study, polyacrylic acid functionalized N-doped porous carbon derived from shaddock peels (PAA/N-SPCs) was fabricated and used as a solid-phase microextraction (SPME) coating for capturing and determining volatile halogenated hydrocarbons (VHCs) from water. Characterizations results demonstrated that the PAA/N-SPCs presented a highly meso/macro-porous hierarchical structure consisting of a carbon skeleton. The introduction of PAA promoted the formation of polar chemical groups on the carbon skeleton. Consequently, large specific surface area, highly hierarchical structures, and abundant chemical groups endowed the PAA/N-SPCs, which exhibited superior SPME capacities for VHCs in comparison to pristine N-SPCs and commercial SPME coatings. Under the optimum extraction conditions, the proposed analytical method presented wide linearity in the concentration range of 0.5-50 ng mL-1, excellent reproducibility with relative standard deviations of 5.8%-7.2%, and low limits of detection varying from 0.0005 to 0.0086 ng mL-1. Finally, the proposed method was applied to analyze VHCs from real water samples and observed satisfactory recoveries ranging from 75% to 116%. This study proposed a novel functionalized porous carbon skeleton as SPME coating for analyzing pollutants from environmental samples.

10.
Light Sci Appl ; 11(1): 337, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36443284

RESUMO

Brain-inspired neuromorphic computing, featured by parallel computing, is considered as one of the most energy-efficient and time-saving architectures for massive data computing. However, photonic synapse, one of the key components, is still suffering high power consumption, potentially limiting its applications in artificial neural system. In this study, we present a BP/CdS heterostructure-based artificial photonic synapse with ultra-low power consumption. The device shows remarkable negative light response with maximum responsivity up to 4.1 × 108 A W-1 at VD = 0.5 V and light power intensity of 0.16 µW cm-2 (1.78 × 108 A W-1 on average), which further enables artificial synaptic applications with average power consumption as low as 4.78 fJ for each training process, representing the lowest among the reported results. Finally, a fully-connected optoelectronic neural network (FONN) is simulated with maximum image recognition accuracy up to 94.1%. This study provides new concept towards the designing of energy-efficient artificial photonic synapse and shows great potential in high-performance neuromorphic vision systems.

11.
Food Chem ; 396: 133646, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35839718

RESUMO

In this work, a magnetic covalent organic framework/graphene oxide composite (MCOF/GO) was rapidly synthesized and developed as a promising candidate for the magnetic solid-phase extraction (MSPE). Combined with HPLC-MS, an efficient and rapid analytical method was established for the determination of oseltamivir (OS) in aquatic products. The resultant composite not only exhibited superior extraction efficiency, but also possessed fast mass transfer kinetic, reducing the pretreatment time greatly. Under optimal conditions, the linear range of the proposed method for OS determination was found to be 0.1-10 µg/kg along with a satisfactory correlation coefficient (R2 = 0.997) and a low limit of detection (LOD, 0.035 µg/kg). Furthermore, the established method was utilized to determine OS in Carp, Yellow croaker, and Shrimp, where the recoveries ranged from 87% to 116%. These results demonstrate the splendid application potential of this method to detect antiviral drugs in actual aquatic products.


Assuntos
Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão/métodos , Grafite , Limite de Detecção , Fenômenos Magnéticos , Estruturas Metalorgânicas/química , Oseltamivir , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem
12.
PeerJ ; 10: e13388, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35539015

RESUMO

Background: This study was performed to construct and validate an early risk warning model of urinary tract infection in patients with neurogenic lower urinary tract dysfunction (NLUTD). Methods: Eligible patients with NLUTD admitted to Shenzhen Longcheng hospital from January 2017 to June 2021 were recruited for model construction, internal validation and external validation. The first time point of data collection was within half a month of patients first diagnosed with NLUTD. The second time point was at the 6-month follow-up. The early warning model was constructed by logistic regression. The model prediction effects were validated using the area under the Receiver Operating Characteristic curve, the Boostrap experiment and the calibration plot of the combined data. The model was externally validated using sensitivity, specificity and accuracy. Results: Six predictors were identified in the model, namely patients ≥65 years old (OR = 2.478, 95%CI [1.215- 5.050]), female (OR = 2.552, 95%CI [1.286-5.065]), diabetes (OR = 2.364, 95%CI) [1.182-4.731]), combined with urinary calculi (OR = 2.948, 95%CI [1.387-6.265]), indwelling catheterization (OR = 1.988, 95%CI [1.003 -3.940]) and bladder behavior training intervention time ≥2 weeks (OR = 2.489, 95%CI [1.233-5.022]); and the early warning model formula was Y = 0.907 ×  age+ 0.937 × sex + 0.860 × diabetes +1.081 × combined with urinary calculi+ 0.687 × indwelling catheterization+ 0.912 × bladder behavior training intervention time-2.570. The results show that the area under the ROC curve is 0.832, which is close to that of 1,000 Bootstrap internal validation (0.828). The calibration plot shows that the early warning model has good discrimination ability and consistency. The external validation shows the sensitivity is 62.5%, the specificity is 100%, and the accuracy is 90%. Conclusion: The early warning model for urinary tract infection in patients with NLUTD is suitable for clinical practice, which can provide targeted guidance for the evaluation of urinary tract infection in patients with NLUTD.


Assuntos
Bexiga Urinaria Neurogênica , Cálculos Urinários , Infecções Urinárias , Humanos , Feminino , Lactente , Idoso , Bexiga Urinária , Estudos Retrospectivos , Bexiga Urinaria Neurogênica/diagnóstico , Infecções Urinárias/diagnóstico
13.
J Hazard Mater ; 421: 126702, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34325291

RESUMO

The preparation of hierarchical porous covalent organic frameworks (HP-COFs) is of great significance due to their inherent porosity and low density. However, it is still very challenging owing to the poor machinability of COFs. Herein, a simple and cost-efficient strategy for the synthesis of HP-COFs was proposed. In particular, p-toluenesulfonic acid and NaCl, both of which can be recycled, are utilized as catalyst and template, respectively. The resulting HP-TpBD-900 featuring abundant macropore and mesopore as well as large specific surface area (~700 m2 g-1) possessed self-floating ability and was turned out to be a promising adsorbent for the efficient removal of sulfamerazine (SMR) in aqueous solution. The maximum adsorption capacity is 168 mg g-1, which is more than twice in comparison to that of material prepared without NaCl template. In addition, no significant decrease in adsorption capacity was observed after 5 cycles. Furthermore, the density functional theory (DFT) method was utilized to elucidate the adsorption mechanism, which could be dominated by hydrogen bonding and C-H···π interaction. This work not only provides a new strategy for the synthesis of HP-COFs, but also contributes to boosting the application of COFs in the field of wastewater treatment.

14.
Mikrochim Acta ; 188(11): 400, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34718874

RESUMO

MOF-derived zink and nitrogen co-doped porous carbon (ZNPC) was synthesized through the pyrolysis of MOF-5-NH2 and used as a solid-phase microextraction (SPME) coating material. Coupled with gas chromatography-mass spectrometry (GC-MS), headspace SPME (HS-SPME) based on ZNPC was adopted for the determination of phenols in food samples. The co-existence of N and Zn in ZNPC endows the derived carbon superior hydrophilicity, which is highly beneficial for phenols capture. After optimizing the conditions of extraction and desorption, a sensitive analytical method was established with low limits of detections (LODs, 0.73-2.3 ng g-1) and wide linear ranges (5-5000 ng g-1). Both the intra-fiber repeatability (RSDs from 2.8-7.3%) and inter-fiber reproducibility (RSDs from 9.7-11.7%) were satisfactory. The established method was applied to phenol determination in beef jerky and duck neck with satisfactory recoveries of 81.2-120.4% and RSDs of 2.8-9.9%, which met well with the requirement of practical application.

15.
J Chromatogr A ; 1655: 462518, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34509690

RESUMO

In this work, hierarchical porous covalent organic frameworks (HP-COFs) foam, named as HP-TpBD, was prepared by using 1,3,5-trimethylphloroglucinol (Tp) and benzidine (BD) as building blocks under the assistant of NaCl template. Its potential application as the sorbent for solid phase extraction (SPE) of sulfonamides (SAs) in meat products were explored by coupling with high performance liquid chromatography-mass spectrum (HPLC-MS) analysis. The key factors affecting extraction efficiency were well studied. Under the optimum conditions, the proposed method exhibited high preconcentration factors of 100, low limit of detection (0.10-0.23 µg/kg), and wide linear ranges (0.5-200 µg/kg). In addition, the determination of SAs in real samples were realized with satisfactory recoveries (82.8-119.9%), demonstrating the applicability of the proposed method. The easy operation, superior extraction affinity and good recycle performance demonstrated the resulting HP-COF foam is a promising adsorbent for the preconcentration of trace organic compounds from complex matrix.


Assuntos
Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Limite de Detecção , Carne/análise , Extração em Fase Sólida , Sulfonamidas/análise
16.
J Colloid Interface Sci ; 604: 823-831, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34303175

RESUMO

Developing high-performance materials for the efficient removal of pharmaceutical contaminants from polluted water has gained tremendous attention but is still a huge challenge. Herein, various N-doped porous carbons (NPCs) were fabricated via a facile and solvent-free pyrolysis strategy by using a mixture of melamine, hexamethylenetetramine, Pluronic F 127, and ZnCl2 as precursor. The resulting NPCs featuring large specific surface areas (803-1002 m2/g) and high nitrogen content (3.79-5.24%) were used as efficient adsorbent for the capture of ibuprofen (IBP) from water. Due to the combination of abundant mesoporous and microporous structure as well as high nitrogen content, the adsorption equilibrium was achieved within 60 min and the adsorption capacity was calculated to be 113 mg/g. Furthermore, it was found that the adsorption capacity exhibited a good correlation with the nitrogen content. In addition, the adsorption capacity of the resulting NPC was well-maintained even after 4 cycles due to its superior stability. The study is expected to encourage the rational design and synthesis of versatile heteroatom-doped porous carbons for practical application in the field of environmental remediation.


Assuntos
Carbono , Ibuprofeno , Adsorção , Nitrogênio , Porosidade
17.
Adv Mater ; 33(27): e2101036, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34057257

RESUMO

Multifunctional reconfigurable devices, with higher information capacity, smaller size, and more functions, are urgently needed and draw most attention in frontiers in information technology. 2D semiconductors, ascribing to ultrathin body and easy electrostatic control, show great potential in developing reconfigurable functional units. This work proposes a novel double-gate field-effect transistor architecture with equal top and bottom gate (TG and BG) and realizes flexible optimization of the subthreshold swing (SS) and threshold voltage (VTH ). While the TG and BG are used simultaneously, as a single gate to drive the transistor, ultralow average SS value of 65.5 mV dec-1 can be obtained in a large current range over 104 , enabling the application in high gain inverter. While one gate is used to initialize the channel doping, full logic swing inverter circuit with high noise margin (over 90%) is demonstrated. Such device prototype is further extended for designing reconfigurable logic applications and can be dynamically switched and well maintained between binary and ternary logics. This study provides important concept and device prototype for future multifunctional logic applications.

18.
Food Chem ; 347: 129002, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482486

RESUMO

A robust magnetic solid-phase extraction (MSPE) method based on magnetic covalent organic framework (MCOF) coupled with high-performance liquid chromatography (HPLC)-ultraviolet (UV)/mass spectrometry (MS) was proposed for the determination of trace diclofenac sodium (DS) in milk. The prepared MCOF exhibited high extraction efficiency, which can be attributed to its high specific surface area as well as strong π-π and hydrophobic interactions between MCOF and DS. In addition, the potential influencing factors, including sample volume, adsorbent dosage, extraction time, and elution parameters, were fully estimated. The experimental results demonstrated that the established method was sensitive for the quantification of DS with high accuracy. Remarkably, the detection limit of DS was found to be 10 ng/kg under the optimal conditions. More impressively, the developed method was successfully applied to monitor trace DS in milk, demonstrating its outstanding durability and practical potential as an appealing method to regular monitor trace pharmaceutical contaminants in real food samples.


Assuntos
Diclofenaco/análise , Magnetismo , Estruturas Metalorgânicas/química , Leite/química , Animais , Cromatografia Líquida de Alta Pressão , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Espectrometria de Massas , Extração em Fase Sólida/métodos
19.
J Environ Manage ; 277: 111389, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069144

RESUMO

Pharmaceutical pollution has emerged as a highly concerned issue due to its adverse effects. Elevated concentrations of pharmaceuticals in water should be regulated to satisfy the requirement for the provision of clean water. Metal-organic frameworks (MOFs) with high specific surface area, controllable porous structure, and facile modification can serve as promising adsorbents for the removal of pharmaceutical contaminants from water. In this review, a selected collection illustrating the reliable strategies and concepts to prepare the MOFs-based materials with superior water stability is described. In addition, recent progress on the adsorptive removal of pharmaceutical pollutant using burgeoning and functional MOFs is also summarized in terms of maximum capacity, equilibrium time, and regenerate ability. Meanwhile, to understand the adsorption mechanism, related interactions including coordination with unsaturated site, pore-filling effect, hydrogen bonding, electrostatic, and π-π stacking are further discussed. Finally, critical perspectives/assessment of future research emphasising on fabricating desirable MOFs and establishing structure-property relationships to facilitate capture performance are identified.


Assuntos
Estruturas Metalorgânicas , Preparações Farmacêuticas , Adsorção , Metais , Água
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