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1.
ACS Appl Mater Interfaces ; 16(24): 31137-31144, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38856774

RESUMEN

In the context of the increasing number of spent lithium-ion batteries, it is urgent to explore cathode regeneration and upcycling solutions to reduce environmental pollution, promote resource reuse, and meet the demand for high-energy cathode materials. Here, a closed-loop recycling method is introduced, which not only reclaims cobalt and lithium elements from spent lithium-ion batteries but also converts them into high-voltage LiCoO2 (LCO) materials. This approach involved pretreatment, chlorination roasting, water leaching, and ion doping to regenerate nickel-doped LCO (Ni-RLCO) materials. The doping of nickel effectively enhances the electrochemical stability of the LCO cathode at 4.5 V. The Ni-RLCO cathode exhibited a high discharge specific capacity of 185.28 mAh/g at a rate of 0.5 C with a capacity retention of 86.3% after 50 cycles and excellent rate capacity of 156.21 mAh/g at 2 C. This work offers a approach in significance for upcycling spent LCO into high-energy-density batteries with long-term cycling stability under high voltage.

2.
Anal Chem ; 96(21): 8837-8843, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38757510

RESUMEN

Breast cancer poses the significance of early diagnosis and treatment. Here, we developed an innovative photoelectrochemical (PEC) immunosensor characterized by high-level dual photocurrent signals and exceptional sensitivity. The PEC sensor, denoted as MIL&Ag2S, was constructed by incorporating Ag2S into a metal-organic framework of MIL-101(Cr). This composite not only enhanced electron-hole separation and conductivity but also yielded robust and stable dual photocurrent signals. Through the implementation of signal switching, we achieved the combined detection of cancer antigen 15-3 (CA15-3) and carcinoembryonic antigen (CEA) with outstanding stability, reproducibility, and specificity. The results revealed a linear range for CEA detection spanning 0.01-32 ng/mL, with a remarkably low detection limit of 0.0023 ng/mL. Similarly, for CA15-3 detection, the linear range extended from 0.1 to 320 U/mL, with a low detection limit of 0.014 U/mL. The proposed strategy introduces new avenues for the development of highly efficient, cost-effective, and user-friendly PEC sensors. Furthermore, it holds promising prospects for early clinical diagnosis, contributing to potential breakthroughs in medical detection and ultimately improving patient outcomes.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Antígeno Carcinoembrionario , Técnicas Electroquímicas , Estructuras Metalorgánicas , Mucina-1 , Compuestos de Plata , Estructuras Metalorgánicas/química , Humanos , Neoplasias de la Mama/diagnóstico , Antígeno Carcinoembrionario/sangre , Antígeno Carcinoembrionario/análisis , Mucina-1/análisis , Mucina-1/sangre , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/análisis , Compuestos de Plata/química , Inmunoensayo/métodos , Técnicas Biosensibles , Femenino , Límite de Detección , Procesos Fotoquímicos , Anticuerpos Inmovilizados/inmunología , Anticuerpos Inmovilizados/química
3.
Anal Chim Acta ; 1303: 342512, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38609275

RESUMEN

BACKGROUND: Various surface-enhanced Raman spectroscopy (SERS) substrate preparation methods have been reported, however, how to tune the "gap" between nanostructures to make more "hot spots" is still a barrier that restricts their application. The gap between nanostructures is usually fixed when the substrates are prepared. In other words, it is hard to tune interparticle distances for maximum electromagnetic coupling during substrate preparation process. Therefore, an in-situ substrate optimization method that could monitor the SERS signal intensity changes, i.e., to find the optimum gap width and particle size, during substrate preparation process is needed. RESULTS: A method based on the galvanic replacement reaction (GRR) is proposed for the in-situ gap width tuning between nanostructures as well as for the optimization of SERS substrates. Noble metal nanoparticles (NPs) form and grow on the sacrificial templates' surface while noble metal ions are reduced by sacrificial metal (oxides) in GRR. Along with the fresh and clean NPs' surface generated, the gap between two noble metal NPs decreases with the growth of the NPs. To demonstrate this strategy, cuprous oxide/Ti (Cu2O/Ti) sacrificial templates were prepared, and then a GRR was carried out with HAuCl4. The real-time SERS detection during GRR show that the optimum reaction time (ORT) is 300 ± 30 s. Furthermore, SERS performance testing was conducted on the optimized substrate, revealing that the detection limit for crystal violet can reach 1.96 × 10-11 M, confirming the feasibility of this method. SIGNIFICANCE AND NOVELTY: By monitoring the in-situ SERS signal of probes during GRR will obtain an "optimal state" of the SERS substrate with optimal gap width and particle size. The SERS substrate preparation and optimization strategy proposed in this article not only provides a simple, efficient, and low-cost method to fabricate surface-clean noble NPs but also paves the way for the in-situ optimization of NPs size and gap width between NPs which could achieve wider applications of SERS.

4.
Mikrochim Acta ; 191(5): 277, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647714

RESUMEN

Widely used organophosphorus pesticide triazophos (TAP) can easily cumulate in aquatic system due to its high stability chemically and photochemically and thus posing significant threat to aquatic creatures and humans' health. Urging demand for rapid determining TAP in water has risen. Photoelectrochemical (PEC) sensing turns out to be a good candidate for its simplicity in fabrication and swiftness in detection. Nevertheless, traditional PEC sensors often lack selectivity as their signal generation primarily relies on the oxidation of organic compounds in the electrolyte by photo-induced holes. To address this limitation, molecularly imprinted polymers (MIPs) can be in combined with PEC sensors to significantly enhance the selectivity. Here, we present a novel approach utilizing a PEC sensor enhanced by carbon-modified titanium dioxide molecularly imprinted polymers (MIP/C/TiO2 NTs). Carbon quantum dot (CQD) modification of titanium dioxide nanotube arrays (C/TiO2 NTs) was achieved through a one-step anodization process, effectively enhancing visible light absorption by narrowing the band gap of TiO2, and CQDs also function as sensitizer accelerating charge transfer for improved and stable photocurrent signals during detection. Our method further incorporates MIPs to heighten the selectivity of the PEC sensor. Electro-polymerization using cyclic voltammetry was employed to polymerize MIPs with pyrrole as the functional monomer and triazophos as the target molecule. The resultant MIP/C/TiO2 NT sensor exhibited remarkable sensitivity, with a detection limit of 0.03 nM (S/N = 3), alongside exceptional selectivity and stability for triazophos detection in water. This offers a promising avenue for efficient, cost-effective, and rapid monitoring of pesticide contaminants in aquatic environments, contributing to the broader goals of environmental preservation and public health.

5.
Adv Mater ; 36(2): e2308844, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37972577

RESUMEN

Optical multiplexing for nanoscale object recognition is of great significance within the intricate domains of biology, medicine, anti-counterfeiting, and microscopic imaging. Traditionally, the multiplexing dimensions of nanoscopy are limited to emission intensity, color, lifetime, and polarization. Here, a novel dimension, optical nonlinearity, is proposed for super-resolved multiplexing microscopy. This optical nonlinearity is attributable to the energy transitions between multiple energy levels of the doped lanthanide ions in upconversion nanoparticles (UCNPs), resulting in unique optical fingerprints for UCNPs with different compositions. A vortex beam is applied to transport the optical nonlinearity onto the imaging point-spread function (PSF), creating a robust super-resolved multiplexing imaging strategy for differentiating UCNPs with distinctive optical nonlinearities. The composition information of the nanoparticles can be retrieved with variations of the corresponding PSF in the obtained image. Four channels multiplexing super-resolved imaging with a single scanning, applying emission color and nonlinearity of two orthogonal imaging dimensions with a spatial resolution higher than 150 nm (1/6.5λ), are demonstrated. This work provides a new and orthogonal dimension - optical nonlinearity - to existing multiplexing dimensions, which shows great potential in bioimaging, anti-counterfeiting, microarray assays, deep tissue multiplexing detection, and high-density data storage.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37913551

RESUMEN

The recycling of spent graphite from waste lithium-ion batteries (LIBs) holds great importance in terms of environmental protection and conservation of natural resources. In this study, a simple two-step method involving heat treatment and solution washing was employed to recycle spent graphite. Subsequently, the recycled graphite was milled with red phosphorus to create a carbon/red phosphorus composite that served as an anode material for the new LIBs, aiming to address the low capacity issue. In a half-cell configuration, the carbon/red phosphorus composite exhibited remarkable cycling stability, maintaining a capacity of 721.7 mAh g-1 after 500 cycles at 0.2 A g-1, and demonstrated an excellent rate performance with a capacity of 276.2 mAh g-1 at 3 A g-1. The improved performance can be attributed to the structure of the composite, where the red phosphorus particles are covered by the carbon layer. This composite outperformed pure recycled graphite, highlighting its potential in enhancing the electrochemical properties of LIBs. Furthermore, when the carbon/red phosphorus composite was assembled into a full-cell configuration with LiCoO2 as the cathode material, it displayed a stable electrochemical performance, further validating its practical applicability. This work presents a promising and green strategy for recycling spent graphite and using it in the production of new batteries. The findings offer a high potential for commercialization, contributing to the advancement of sustainable and ecofriendly energy storage technologies.

7.
Mikrochim Acta ; 190(6): 244, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37247003

RESUMEN

A photoelectrochemical molecular imprinting sensor based on Au/TiO2 nanocomposite was constructed for the detection of dibutyl phthalate. Firstly, TiO2 nanorods were grown on fluorine-doped tin oxide substrate by hydrothermal method. Then, gold nanoparticles were electrodeposited on TiO2 to fabricate Au/TiO2. Finally, molecular imprinted polymer was electropolymerized on the Au/TiO2 surface to construct MIP/Au/TiO2 PEC sensor for DBP. The conjugation effect of MIP accelerates the electron transfer between TiO2 and MIP, which can greatly improve the photoelectric conversion efficiency and sensitivity of the sensor. In addition, MIP can also provide sites for highly selective recognition of dibutyl phthalate molecules. Under optimal experimental conditions, the prepared photoelectrochemical sensor was used for the quantitative determination of DBP and the results showed a wide linear range (50 to 500 nM), a low limit of detection (0.698 nM), and good selectivity. The sensor was used in a study of real water samples to show that it has promising applications in environmental analysis.

8.
Nanoscale ; 15(9): 4353-4360, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36752732

RESUMEN

The supramolecular self-assembly behavior of a pair of low-symmetry tetracarboxylic acid molecules (H4OBDB and H4ADDI) and their co-assembly behavior with TMA as a bridging molecule were studied at the liquid-solid interface. Scanning tunneling microscope (STM) observations revealed that H4OBDB and H4ADDI molecules both tend to form O-shaped dimers but end up forming different types of self-assembly structures. We also investigated the construction of two-component co-assembly structures by mixing H4OBDB or H4ADDI molecules with bridging molecules such as TMA. The two formed co-assembly structures are similar. Based on the analysis of the STM results and the density functional theory (DFT) calculations, the formation mechanism of the assembled structures was revealed.

9.
Biosens Bioelectron ; 219: 114811, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36308836

RESUMEN

Cancer is a leading cause of death globally and early diagnosis is of paramount importance for identifying appropriate treatment pathways to improve cancer patient survival. However, conventional methods for cancer detection such as biopsy, CT scan, magnetic resonance imaging, endoscopy, X-ray and ultrasound are limited and not efficient for early cancer detection. Advancements in molecular technology have enabled the identification of various cancer biomarkers for diagnosis and prognosis of the deadly disease. The detection of these biomarkers can be done by biosensors. Biosensors are less time consuming compared to conventional methods and has the potential to detect cancer at an earlier stage. Compared to conventional biosensors, photoelectrochemical (PEC) biosensors have improved selectivity and sensitivity and is a suitable tool for detecting cancer agents. Recently, 2D carbon materials have gained interest as a PEC sensing platform due to their high surface area and ease of surface modifications for improved electrical transfer and attachment of biorecognition elements. This review will focus on the development of 2D carbon nanomaterials as electrode platform in PEC biosensors for the detection of cancer biomarkers. The working principles, biorecognition strategies and key parameters that influence the performance of the biosensors will be critically discussed. In addition, the potential application of PEC biosensor in clinical settings will also be explored, providing insights into the future perspective and challenges of exploiting PEC biosensors for cancer diagnosis.

10.
Chemistry ; 29(19): e202203787, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36585826

RESUMEN

Zinc-air batteries (ZABs) have been considered as one of the most promising energy storage devices to solve the problem of energy crisis and environmental pollution. In this work, we reported the synthesis of nitrogen-doped MnO2 (N-MnO2 ) to replace the noble metal electrocatalysts for air cathode in ZABs. The doped N atoms here introduced more Mn3+ and oxygen vacancies for MnO2 , enhancing charge transfer property and accelerating surface intermediate product during the oxygen reduction reaction (ORR). Hence, the best N-MnO2 achieved remarkable electrocatalytic activities towards ORR (half-wave potential of 0.797 V vs. RHE), and reversible oxygen overpotential of around 0.842 V, which is better than or comparable to the Pt/C and Mn-based catalysts reported recently. Moreover, the homemade ZABs based on N-MnO2 showed the maximum power density of 132.8 mW cm-2 and excellent cyclic stability.

11.
Mikrochim Acta ; 189(12): 453, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36411347

RESUMEN

A photoelectrochemical (PEC) aptasensor based on CdSe@SnS2 nanocomposite has been developed to detect sulfamethazine (SMZ). The introduction of CdSe into SnS2 displayed an amplified PEC signal, which was higher than that of pure CdSe and SnS2, attributable to its enhanced light harvesting capacity and promoted PEC energy conversion efficiency. Due to the formation of specific non-covalent bonds, the SMZ-binding aptamer (SBA) has significant specificity and sensitivity. When SMZ was incubated on a CdSe@SnS2 modified electrode fixed with aminated SBA, the formation of the SMZ/SBA complex increased the space resistance of electron transfer and hindered the electronic migration between the electrodes, resulting in a decrease in photocurrent. The greater the adsorbed amount on the SBA, the lower the photocurrent produced.  Under optimized conditions the photocurrent response of MCH/SBA/CdSe@SnS2/FTO was inversely proportional to the SMZ concentration in the range 0.1 to 100 pM, with a detection limit (3 S/N) of 0.025 pM (at 0 V vs. Hg/HgCl). The recoveries ranged from 95.8 to 104% with relative standard deviations (RSDs) < 6.3% (n = 3) in actual water sample. This PEC aptasensor which shows considerable potential in SMZ detection applications has high selectivity, reproducibility, and good stability.


Asunto(s)
Técnicas Biosensibles , Compuestos de Cadmio , Nanocompuestos , Compuestos de Selenio , Sulfametazina , Compuestos de Cadmio/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados , Titanio/química , Compuestos de Selenio/química , Nanocompuestos/química
12.
Nano Lett ; 22(17): 7136-7143, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36018249

RESUMEN

Single-beam super-resolution microscopy, also known as superlinear microscopy, exploits the nonlinear response of fluorescent probes in confocal microscopy. The technique requires no complex purpose-built system, light field modulation, or beam shaping. Here, we present a strategy to enhance this technique's spatial resolution by modulating excitation intensity during image acquisition. This modulation induces dynamic optical nonlinearity in upconversion nanoparticles (UCNPs), resulting in variations of nonlinear fluorescence response in the obtained images. The higher orders of fluorescence response can be extracted with a proposed weighted finite difference imaging algorithm from raw fluorescence images to generate an image with higher resolution than superlinear microscopy images. We apply this approach to resolve single nanoparticles in a large area, improving the resolution to 132 nm. This work suggests a new scope for the development of dynamic nonlinear fluorescent probes in super-resolution nanoscopy.


Asunto(s)
Colorantes Fluorescentes , Nanopartículas , Algoritmos , Microscopía Confocal/métodos
13.
Nanoscale ; 14(6): 2419-2426, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35098290

RESUMEN

The supramolecular self-assembly behavior of a low-symmetric aromatic carboxylic acid molecule (H5BHB) and its co-assembly behavior with a series of pyridine molecules (BPD, BPDYB and TPDYB) were studied at the heptanoic acid/HOPG liquid-solid interface. Scanning tunneling microscopy (STM) observations revealed that H5BHB molecules tend to form dimeric building blocks which then assemble into a close-packed structure. BPD, BPDYB and TPDYB pyridine molecules were all able to form a stable two-component co-assembled structure with the H5BHB molecule, and in these co-assembled structures, the H5BHB molecule still takes the form of a dimer. It was found that the pyridine molecules were able to regulate the self-assembly structure of the H5BHB molecule, and the molecular arrangement of the co-assembly structures varies with the shape of the pyridine molecules. Based on the analysis of the STM results and density functional theory (DFT) calculations, the formation mechanism of the assembled structures was revealed.

14.
Biosens Bioelectron ; 189: 113389, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34091283

RESUMEN

Designing a photoelectrochemical (PEC) immunosensor that can produce dual photocurrent signals which can refer to each other is a great importance but a big challenge. In this manuscript, a novel dual photocurrent signals immunosensor was constructed for the detection of α-fetoprotein (AFP). Unlike the usual method of using two composite materials to provide cathode and anode photocurrent respectively, this work applies only one compound of MIL-101 (Cr) and CdSe quantum dots (QDs). Thereinto, we found that the photocurrent polarity of MIL-101(Cr) would switch by adjusting applied voltage. And then CdSe QDs was introduced by simple ultrasound mixing to boost the dual photocurrent signals. Furthermore, in the composite of M&C, the electron transfer path between MIL-101(Cr) and CdSe QDs may switch between "Z-type" and "Ⅱ-type" by adjusting voltage. Benefiting by the dual signals, the proposed sensor can not only perform sensitively quantitative detection of α-fetoprotein (AFP), but also can intuitively estimate the accuracy and reliability of the test result by determining whether the corresponding relationship of "cathode photocurrent-analyte concentration-anode photocurrent" is established. The linear ranges of the sensing electrodes as cathode and anode are the same, both from 0.1 to 300 ng mL-1. The limit of detection (LOD) is 0.082 ng mL-1 (S/N = 3) when it used as an anode, and the LOD is 0.054 ng mL-1 (S/N = 3) when it served as cathode. Furthermore, this sensor showed acceptable stability, reproducibility, specificity, and feasibility of detecting AFP in human serum, which has broad development prospects in the early clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , Compuestos de Cadmio , Puntos Cuánticos , Compuestos de Selenio , Técnicas Electroquímicas , Humanos , Inmunoensayo , Límite de Detección , Estructuras Metalorgánicas , Reproducibilidad de los Resultados , alfa-Fetoproteínas
15.
ACS Nano ; 15(3): 4789-4801, 2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33645990

RESUMEN

Here, a current-accelerated phase cycling by an in situ current-induced oxidation process was demonstrated to reversibly switch the local metallic Cu and semiconducting Cu2O phases of patterned polycrystalline copper nanobelts. Once the Cu nanobelts were applied by a direct-current bias of ∼0.5 to 1 V in air with opposite polarities, the resistance between several hundred ohms and more than MΩ can be manipulated. In practice, the thickness of 60 nm with a moderate grain size inhibiting both electromigration and permanent oxidation is the optimized condition for reversible switching when the oxygen supply is sufficient. More than 40% of the copper localized beneath the positively biased electrode was oxidized assisted by the Joule heating, blocking the current flow. On the contrary, the reduction reaction of Cu2O was activated by the thermally assisted electromigration of Cu atoms penetrating the interlayer at the reverse bias. Finally, based on a high on/off ratio, the fast switching and the scalable production, reusable feasibility based on copper nanobelts such as the memristor array was demonstrated.

16.
Langmuir ; 37(6): 2153-2160, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33527825

RESUMEN

A three-component supramolecular co-assembly structure formed at the liquid-solid interface by employing a shape-persistent π-conjugated macrocycle (16mer) and two guest molecules (COR and C60) is demonstrated. Scanning tunneling microscopy (STM) observations revealed that 16mer can serve as a versatile host molecule that can co-assemble with both COR and C60 guest molecules to form stable two-component structures, where the COR guest molecule filled in the gap between the side chains of adjacent 16mer molecules, and the C60 guest molecule entered the inner cavity of 16mer. It was found that the adding sequence of COR and C60 guest molecules is crucial to the resulting co-adsorption structure in the three-component system. To obtain the intriguing 16mer-COR-C60 three-component co-assembly structure, the 16mer and COR two-component co-assembly structure should first be constructed on a HOPG surface, followed by addition of C60. Based on the analysis of the STM results and the density functional theory (DFT) calculations, the formation mechanism of the assembled structures was revealed.

17.
Chemistry ; 27(13): 4291-4296, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33411374

RESUMEN

A simple, cost-effective strategy was developed to effectively improve the electron transfer efficiency as well as the power output of microbial fuel cells (MFCs) by decorating the commercial carbon paper (CP) anode with an advanced Mo2 C/reduced graphene oxide (Mo2 C/RGO) composite. Benefiting from the synergistic effects of the superior electrocatalytic activity of Mo2 C, the high surface area, and prominent conductivity of RGO, the MFC equipped with this Mo2 C/RGO composite yielded a remarkable output power density of 1747±37.6 mW m-2 , which was considerably higher than that of CP-MFC (926.8±6.3 mW m-2 ). Importantly, the composite also facilitated the formation of 3D hybrid biofilm and could effectively improve the bacteria-electrode interaction. These features resulted in an enhanced coulombic efficiency up 13.2 %, nearly one order of magnitude higher than that of the CP (1.2 %).

18.
J Colloid Interface Sci ; 567: 410-418, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32086025

RESUMEN

Designing a low-cost, high-efficiency and robust doped-carbon-based oxygen reduction reaction electrocatalyst for large-scale implementations of fuel cells is highly desirable but challenging. In this work, we report a new type of hollow Fe3O4 with oxygen vacancy incorporating on mesoporous carbon prepared by pyrolyzing mesoporous carbon enriched with oxygen-containing functional groups, in combination with ferric acetylacetonate. The catalysts possess high specific surface area with predominantly mesoporous architecture and ultrahigh nitrogen content (up to 7.47 wt%). Benefiting from the integration of abundant active nitrogen and Fe-Nx species, and synergistic effect between Fe3O4 nanoparticles cooperated with oxygen vacancy and N-doped carbon, the half-wave potential of the preparing hybrid catalyst is 30 mV more positive than that of the commercial Pt/C catalyst in alkaline medium, and exhibits a high selectivity (4 e- process), and outstanding long-term stability. More importantly, the C-FePPDA-900 catalyst displays a high power density (106 mW cm-2) and specific capacity of 724 mAh gzn-1 when it is used as an air cathode catalyst in a specifically assembling Zn-air cell, superior to those of most reported catalysts.

19.
Nanoscale Res Lett ; 15(1): 7, 2020 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-31933114

RESUMEN

Particulate matter is one of the main pollutants, causing hazy days, and it has been serious concern for public health worldwide, particularly in China recently. Quality of outdoor atmosphere with a pollutant emission of PM2.5 is hard to be controlled; but the quality of indoor air could be achieved by using fibrous membrane-based air-filtering devices. Herein, we introduce nanofiber membranes for both indoor and outdoor air protection by electrospun synthesized polyacrylonitrile:TiO2 and developed polyacrylonitrile-co-polyacrylate:TiO2 composite nanofiber membranes. In this study, we design both polyacrylonitrile:TiO2 and polyacrylonitrile-co-polyacrylate:TiO2 nanofiber membranes with controlling the nanofiber diameter and membrane thickness and enable strong particulate matter adhesion to increase the absorptive performance and by synthesizing the specific microstructure of different layers of nanofiber membranes. Our study shows that the developed polyacrylonitrile-co-polyacrylate:TiO2 nanofiber membrane achieves highly effective (99.95% removal of PM2.5) under extreme hazy air-quality conditions (PM2.5 mass concentration 1 mg/m3). Moreover, the experimental simulation of the test in 1 cm3 air storehouse shows that the polyacrylonitrile-co-polyacrylate:TiO2 nanofiber membrane (1 g/m2) has the excellent PM 2.5 removal efficiency of 99.99% in 30 min.

20.
Biosens Bioelectron ; 150: 111949, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31929086

RESUMEN

The fast and accurate detection of Carcinoembryonic Antigen (CEA) plays an important role in clinical cancer treatment and therapy. An ultrasensitive photoelectrochemical (PEC) immunosensor for the detection of CEA was constructed using CdSe@BiVO4 co-sensitized TiO2 nanorods as photoactive materials. TiO2 nanorods were assembled on the FTO modified electrode to immobilize capture antibodies. With a sandwich immunoassay format, CEA and signal antibodies labelled CdSe@BiVO4 were introduced in sequence via specific immunoreaction, and the ultrahigh sensitivity of this immunoassay results from the following three aspects. Firstly, the co-sensitization of BiVO4 and CdSe extends the absorption range of TiO2 from ultraviolet region to visible light region, which can adequately utilize the light energy; Secondly, the effective matching of energy levels among TiO2, CdSe and BiVO4 accelerates the separation and transfer of photogenerated electron-hole pairs and significantly improves the PEC performance; Finally, the introduced Au evidently expedites the interfacial electron transfer from TiO2 to FTO electrode, further resulting in noticeably increased photocurrent. Based on multiple signal amplification strategy, a largely linear detection range from 0.01 ng mL-1 to 50 ng mL-1 with a low detection limit (0.5 pg mL-1) were obtained. In addition, the prepared immunosensor with attractive properties provides a promising platform for PEC detection.


Asunto(s)
Anticuerpos Inmovilizados/química , Técnicas Biosensibles/métodos , Bismuto/química , Compuestos de Cadmio/química , Antígeno Carcinoembrionario/sangre , Compuestos de Selenio/química , Titanio/química , Vanadatos/química , Técnicas Electroquímicas/métodos , Humanos , Inmunoensayo/métodos , Límite de Detección , Nanotubos/química , Nanotubos/ultraestructura
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