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1.
J Colloid Interface Sci ; 661: 897-907, 2024 May.
Article in English | MEDLINE | ID: mdl-38330662

ABSTRACT

Adsorbents with dual-component active phases have attracted much attention owing to their potential application in synergistic H2S removal. The influence of spatial arrangements of two components within a support matrix on their desulfurization performance was investigated through regulating the mutual arrangements of CuO and MgO on an activated carbon surface. Their spatial locations were found to remarkably affect interfacial interactions, local pH, the conductivity of adsorbents, and electronic structure of copper oxide. A close contact of CuO with the carbon surface led to strong interactions of both components, inhibiting the reduction of CuO and decreasing its reactivity with H2S. On the other hand, a proximity of MgO to the carbon surface increased local pH, promoting the oxidation of H2S into elemental S, instead of sulfates. Cu+ in the copper oxide phase increased the desulfurization performance due to its ability to activate oxygen and to accelerate a lattice diffusion. Enhanced surface conductivity due to the interfacial interactions improved the desulfurization efficiency and favored the formation of elemental S through promoting an electron transfer in redox reactions.

2.
J Colloid Interface Sci ; 641: 707-718, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36965342

ABSTRACT

Isoreticular bimetal M-Cu-BTC has considerable potential in improving the sulfides removal performance of Cu-BTC. Herein, three transition metals, namely, Zn2+, Ni2+ and Co2+, were assessed to fabricate M-Cu-BTC, a desirable isoreticular bimetal. Results demonstrated the feasibility of using Zn2+ to fabricate an isoreticular bimetallic Zn-Cu-BTC. The Zn2+ doping content of Zn-Cu-BTC was varied to investigate its influence on the hydrogen sulfide (H2S) and methyl sulfide (CH3SCH3) removal performance of Cu-BTC. The experimental results indicated that the sulfides removal performance of Zn-Cu-BTC increased and then decreased with increasing Zn doping content. The highest H2S and CH3SCH3 removal capacities of 84.3 and 93.9 mg S/g, respectively, were obtained when the Zn2+ doping content was 17%. The hybridisation of Zn and Cu in Zn-Cu-BTC induced a strong interaction between them. This interaction increased the binding energies of H2S and CH3SCH3 towards the Cu and Zn adsorption sites while weakening the bond order between Zn and Cu. The weakened bond order made the Zn-Cu bonds easier to form metal sulfides during desulfurization process, thereby synergistically enhancing sulphide removal.

3.
Acta Biomater ; 158: 686-697, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36623782

ABSTRACT

Selectively generating active free radical (AFR) in tumor microenvironment (TME) can promote irreversible oxidation of biomolecules and damage tumor cells, resulting in effective tumor inhibition. However, therapeutic efficacy of AFR-based tumor suppression approaches is often limited by insufficient amount of H2O2 or O2 within TME. To overcome this obstacle, we design a pH/photothermal dual responsive nanosystem (PFeSA@AS) for combined photothermal and nanocatalytic therapy in the near-infrared biowindow. Here the Fe single-atom dispersed N, S-doped carbon nanosheets (FeSA) nanozyme is dispersed by phospholipid-polyethylene glycol-amine (DSPE-PEG-NH2), and further loads artesunate (AS) via an amide reaction. Upon 808-nm laser irradiation in TME, the AS is released and further be catalyzed by the FeSA nanozyme to produce cytotoxic C-centered AFRs, and further be accelerated due to the photothermal conversion performance of FeSA (23.35%). The nanocatalytic process of FeSA nanozyme is realized by density functional theory (DFT). The tumor inhibition rates of a CT26 xenograft model is 92% through a photothermal-enhanced nanocatalytic synergistic therapy, and negligible systematic toxicity is observed. This work offers a potential paradigm of multifunctional single atomic catalysts (SACs) for enhancing tumor nanocatalytic therapy. STATEMENT OF SIGNIFICANCE: We designed a pH/photothermal dual responsive nanosystem (PFeSA@AS) for nanocatalytic therapy: (1) the nanosystem responsively releases AS under 808-nm laser irradiation in TME; (2) FeSA in the nanosystem can act as heme mimetic to convert AS into high cytotoxic C-centered free radicals for nanocatalytic therapy; (3) the photothermal conversion performance of FeSA further enhances the catalytic process to yield abundant AFR. Both in vitro and in vivo results demonstrate that this nanosystem can efficiently inhibit tumor growth through a photothermal-enhanced nanocatalytic synergistic therapy.


Subject(s)
Hyperthermia, Induced , Neoplasms , Humans , Phototherapy , Cell Line, Tumor , Artesunate/pharmacology , Hydrogen Peroxide/pharmacology , Catalysis , Tumor Microenvironment
4.
Anal Biochem ; 663: 115028, 2023 02 15.
Article in English | MEDLINE | ID: mdl-36572216

ABSTRACT

A target-triggered and exonuclease-Ⅲ-assisted strand displacement, dual-recycling amplification reaction-based biosensor was developed for the rapid, ultrasensitive and accurate detection of kanamycin. The robust profiling platform was constructed using high conductive MXene/VS2 for the electrode surface modification and high active CeCu2O4 bimetallic nanoparticles as nanozyme to improve the sensitivity as well as the catalytic signal amplification of the biosensor. Using the dual supplementary recycling of primer DNA and hairpin DNA, the electrochemical platform could accurately detect kanamycin to as low as 0.6 pM from the range of 5 pM to 5 µM. By profiling five other antibiotics, this platform exhibited high specificity, enhanced repeatability and reproducibility. Based on these intrinsic characteristics and by utilizing milk and water samples, the as-designed biosensor offers a remarkable strategy for antibiotic detection due to its favorable analytical accuracy and reliability, thereby demonstrating potential application prospect for various antibiotic biosensing in food quality control, water contamination detection and biological safety analysis.


Subject(s)
Biosensing Techniques , Kanamycin , Kanamycin/analysis , Reproducibility of Results , Electrochemical Techniques , Anti-Bacterial Agents/analysis , DNA , Biosensing Techniques/methods , Water , Limit of Detection
5.
ACS Nano ; 16(5): 7512-7524, 2022 05 24.
Article in English | MEDLINE | ID: mdl-35451839

ABSTRACT

The key to controlling the spread of the coronavirus disease 2019 (COVID-19) and reducing mortality is highly dependent on the safe and effective use of vaccines for the general population. Current COVID-19 vaccination practices (intramuscular injection of solution-based vaccines) are limited by heavy reliance on medical professionals, poor compliance, and laborious vaccination recording procedures, resulting in a waste of health resources and low vaccination coverage, etc. In this study, we developed a smart mushroom-inspired imprintable and lightly detachable (MILD) microneedle platform for the effective and convenient delivery of multidose COVID-19 vaccines and decentralized vaccine information storage. The mushroom-like structure allows the MILD system to be easily pressed into the skin and detached from the patch base, acting as a "tattoo" to record the vaccine counts in situ without any storage equipment, offering quick accessibility and effortless readout, saving a great deal of valuable time and energy for both patients and health professionals. After loading inactivated SARS-CoV-2 virus-based vaccines, MILD system induced a high level of antibodies against the SARS-CoV-2 receptor-binding domain (RBD) in vivo without eliciting systemic toxicity and local damage. Collectively, this smart delivery platform serves as a promising carrier to improve COVID-19 vaccination efficacy through its dual capabilities of vaccine delivery and in situ data storage, thus exhibiting great potential for helping to contain the COVID-19 pandemic or a resurgence.


Subject(s)
COVID-19 , Humans , COVID-19/prevention & control , COVID-19 Vaccines , Pandemics/prevention & control , SARS-CoV-2 , Vaccination/methods , Information Storage and Retrieval , Antibodies, Viral
6.
J Healthc Eng ; 2022: 3002993, 2022.
Article in English | MEDLINE | ID: mdl-35126915

ABSTRACT

The problem of poor children's psychological development has been widely concerned by governments all over the world. At present, the research results of poor children's psychological development show that poor children mainly have cognitive, mental health, and behavioral problems. This paper studies the personality traits and their influencing factors of children from poor families from the perspective of psychological education. By giving the definition of children from poor families and poor families, this paper analyzes the psychological development of poor children, analyzes the personality traits and influencing factors of children from poor families from the perspective of psychological education, obtains the standard scores of 16 personality traits and their dimensional personality factors and personality factors, and uses the clustering method to realize the difference analysis of personality characteristics of various samples. From the perspective of quantitative psychological education, this paper analyzes the correlation between personality traits and influencing factors of children from poor families in order to provide basis and reference for the government and society to implement targeted poverty alleviation and cut off the intergenerational transmission of poverty.


Subject(s)
Mental Health , Personality , Child , Educational Status , Humans
7.
Front Psychol ; 12: 693377, 2021.
Article in English | MEDLINE | ID: mdl-34512448

ABSTRACT

This study aims to analyze the influencing factors and training plans of cultivating new entrepreneurs in the new era based on industrial cluster theory. First, the status of the research on the correlation between psychological characteristics and entrepreneurial performance of new entrepreneurs is reviewed. Second, 200 new entrepreneurs in the Xi'an City of Shaanxi Province are randomly selected as the research objects. An empirical model of the correlation between entrepreneurial psychological characteristics and entrepreneurial performance is innovatively proposed. Finally, the questionnaire data are analyzed by correlation analysis and SPSS 26.0 (Chicago) statistical analysis. The results show that most of the entrepreneurs are between 30 and 50 years old, with a larger number of mens, and most graduate from junior colleges. The gender and education level of the new entrepreneurs have a little impact on their entrepreneurial performance (P > 0.05), whereas their age has a significant impact on their entrepreneurial performance (P < 0.05). Moreover, there is a significant correlation between the psychological characteristics of the entrepreneur and the two dimensions of entrepreneurial performance (development and profitability) (P < 0.05). This shows that the key to cultivating new entrepreneurs is to develop their age and psychological characteristics, which can enhance the entrepreneurial ability of new entrepreneurs and provide a basis for cultivating multidimensional entrepreneurial talents in new enterprises.

8.
Biosens Bioelectron ; 191: 113474, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34246894

ABSTRACT

Accelerated glucose uptake and "aerobic glycolysis" of tumor cells generates a high-level lactate in extracellular space and within tumor tissue, which is thought to be a hallmark of tumor and closely correlated with tumor development. Here, we report the development of an enzyme-free electrochemical sensing platform based on a Pt-microneedle electrode functionalized with Au nanoparticles (Au-NPs) decorated polydopamine nanospheres (PDA-NSs), and explore its practical application in in vitro and in vivo detection of lactate in different biological samples. Our results demonstrate that in virtue of the nanostructured merits and high electrocatalytic activity, the resultant nanohybrid-microelectrode exhibits good sensitivity and selectivity to the nonenzymatic electrochemical detection of lactate, with a detection limit of 50 µM, a liner range of 0.375-12 mM, and a sensitivity of 11.25 mA mM-1 cm-2, as well as a good anti-interference ability to other active small molecules. The platform quantifies lactate in complex bio-fluids, including cancerous and non-cancerous cell culture media, as well as serum samples, with detecting time 7.5-fold faster than does a clinically-used approach. Moreover, owing to miniaturized size and satisfactory electrochemical performance, the sensor achieves in vivo recording of lactate-related characteristic voltammetric signals within a living tumor, which are positively correlated with tumor burden and growth. Therefore, the platform cannot only be employed for cancer metabolic investigation, but also potentially for clinical assessment of tumor progression, and even clinical diagnosis of other lactate metabolism disorders.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Neoplasms , Electrochemical Techniques , Gold , Humans , Hydrogen Peroxide , Lactic Acid , Limit of Detection , Microelectrodes , Neoplasms/diagnosis
9.
Biomaterials ; 269: 120388, 2021 02.
Article in English | MEDLINE | ID: mdl-33172606

ABSTRACT

Immunogenic chemotherapy (IC) is a type of chemotherapy where certain chemodrugs induce immunogenic cancer cell death (ICD), which in turn arouses T cell antitumor immunity. However, IC concurrently upregulates a key immune suppressor, indoleamine-2,3-dioxygenase (IDO), in both cancer cells and immune cells. IDO-mediated immunosuppression significantly offsets IC's therapeutic benefits in cancer patients, suggesting a necessity of combination with IDO inhibitors. Here, we report an enzyme-, pH-, and redox-triple-sensitive nanosystem using mesoporous silica nanoparticles (MSNs) as a core encapsulating doxorubicin (DOX, an immunogenic chemodrug); the core is coated with a shell (ß-CD-PEI/Ge1MT) for co-delivering 1-methyl-D-tryptophan (1 MT, an IDO inhibitor). By using these responsivenesses sequentially triggering the release of 1 MT into tumor extracellular compartment and DOX into intracellular endo/lysosomal compartment, this nanosystem (DOX@GMTMSNs) precisely delivers the drugs to their target cells residing in different compartments. Released 1 MT uptake by IDO-expressing dendritic cells (DCs) and cancer cells suppresses IDO activity, reducing immunosuppressive Tregs' presence; DOX unloaded within cancer cells induces ICD, promoting effector T-cell infiltration. In two preclinical cancer models, DOX@GMTMSNs potentiate both tumor local and systemic antitumor immunity, suppressing primary tumor growth by 78% with an 83% reduction in metastatic foci, as well as extending animal survival, thus strongly demonstrating DOX@ GMTMSNs' clinical translational potential.


Subject(s)
Neoplasms , Tumor Microenvironment , Animals , Doxorubicin , Enzyme Inhibitors , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase
10.
Chem Commun (Camb) ; 55(82): 12352-12355, 2019 Oct 10.
Article in English | MEDLINE | ID: mdl-31559405

ABSTRACT

We report a new biofunctionalized nanoplatform based on hyaluronic acid-coated gold-nano-dot-decorated hollow carbon nanospheres (AuHCNs-HA) for microRNA imaging in living cells. Importantly, the HA-coated nanoplatform could be internalized into target cells via CD44 receptor-mediated endocytosis. It can be further applied for intracellular miR-21 imaging in CD44-positive colorectal cancer cells.


Subject(s)
Colorectal Neoplasms/metabolism , Gold/chemistry , Metal Nanoparticles/chemistry , MicroRNAs/analysis , Optical Imaging/methods , Hyaluronan Receptors/metabolism , Hyaluronic Acid/chemistry , Optical Imaging/instrumentation , Particle Size , Porosity , Surface Properties
11.
J Colloid Interface Sci ; 555: 548-557, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31404839

ABSTRACT

Herein, an unusual strategy is reported to enhance the H2S uptake capacity by varying the ZnO-support interaction and controlling the acid-basic environment of the pore channel; this is in place of the generally reported method of decreasing ZnO nanoparticle size and optimizing their porosity. With this regard, coal based activated carbon (AC) is selected as the support and the interaction with ZnO is tuned by introducing N species on AC surface through a soft nitriding strategy. Our strategy is confirmed to be prospective based on the fact that the N-modifying AC supported ZnO adsorbent show a maximum breakthrough sulfur capacity (BSC) of 62.5 mg S/g sorbent, two times larger than that without N-modification (30.5 mg S/g sorbent). The enhanced BSC is attributed to the introduced N species, which not only increases the basicity of the water film condensed in the pores, promoting the dissociation of H2S and H2O, but also influences the electronic structure of ZnO, accelerating the rate of lattice diffusion during in sulfidation process. It is also found that the high BSC of sorbent with N modification is related to the doped N concentrations, ZnO dispersion and the material porosity. This paper provides a new insight for designing supported ZnO based adsorbents.

12.
Langmuir ; 35(24): 7759-7768, 2019 Jun 18.
Article in English | MEDLINE | ID: mdl-31140809

ABSTRACT

Preparation of well-dispersed ZnO nanograins is necessary to improve their reactivity toward room-temperature H2S removal. However, the challenge to design such a ZnO-based adsorbent with high ZnO loading is yet to be fulfilled. Herein, a facile sol-gel strategy is reported for the preparation of ZnO/SiO2 adsorbents for efficient H2S removal, by innovating a gel-drying method and simultaneously controlling ZnO grain formation through optimizing the molar ratio of ethylene glycol (EG)/nitrates in its precursors. The fabricated adsorbent embedded well-dispersed ZnO nanograins, of approximately 10-15 nm, into a SiO2 matrix (57 wt % ZnO loading) and thus yielded a high H2S removal capacity of 108.9 mg S/g sorbent. Therein, EG was used as a modifier for inhibiting the formation of a denser SiO2 network during the gel drying process and was used as a fuel for promoting the decomposition of nitrates and increasing the surface area of the composites in the subsequent calcination. Modulating the molar ratio of EG/nitrates ≤ 2 in precursors or traditional drying of the gel in an oven should be avoided because these would lead to the oxidation of EG by metallic nitrates and form carboxylate complexes during the gel-drying process. Although the produced ZnO grains had a very small size of less than 5 nm, a layer of monodentate ZnCO3 impurity was formed on the ZnO surface, which will drastically decrease the reactivity of ZnO toward H2S. According to the encouraging results from CuO and Co3O4, this strategy has proved to be versatile for the preparation of other metal oxide/SiO2 adsorbents.

13.
PLoS One ; 11(6): e0157369, 2016.
Article in English | MEDLINE | ID: mdl-27333072

ABSTRACT

Nickel laterites cannot be effectively used in physical methods because of their poor crystallinity and fine grain size. Na2SO4 is the most efficient additive for grade enrichment and Ni recovery. However, how Na2SO4 affects the selective reduction of laterite ores has not been clearly investigated. This study investigated the decomposition of laterite with and without the addition of Na2SO4 in an argon atmosphere using thermogravimetry coupled with mass spectrometry (TG-MS). Approximately 25 mg of samples with 20 wt% Na2SO4 was pyrolyzed under a 100 ml/min Ar flow at a heating rate of 10°C/min from room temperature to 1300°C. The kinetic study was based on derivative thermogravimetric (DTG) curves. The evolution of the pyrolysis gas composition was detected by mass spectrometry, and the decomposition products were analyzed by X-ray diffraction (XRD). The decomposition behavior of laterite with the addition of Na2SO4 was similar to that of pure laterite below 800°C during the first three stages. However, in the fourth stage, the dolomite decomposed at 897°C, which is approximately 200°C lower than the decomposition of pure laterite. In the last stage, the laterite decomposed and emitted SO2 in the presence of Na2SO4 with an activation energy of 91.37 kJ/mol. The decomposition of laterite with and without the addition of Na2SO4 can be described by one first-order reaction. Moreover, the use of Na2SO4 as the modification agent can reduce the activation energy of laterite decomposition; thus, the reaction rate can be accelerated, and the reaction temperature can be markedly reduced.


Subject(s)
Mass Spectrometry/methods , Minerals/chemistry , Nickel/chemistry , Sulfates/chemistry , Thermogravimetry/methods , Kinetics , Microscopy, Electron, Scanning , Temperature , Water/chemistry , X-Ray Diffraction
14.
ACS Appl Mater Interfaces ; 6(23): 21167-77, 2014 Dec 10.
Article in English | MEDLINE | ID: mdl-25382853

ABSTRACT

A series of novel zinc oxide-silica composites with three-dimensionally ordered macropores (3DOM) structure were synthesized via colloidal crystal template method and used as sorbents for hydrogen sulfide (H2S) removal at room temperature for the first time. The performances of the prepared sorbents were evaluated by dynamic breakthrough testing. The materials were characterized before and after adsorption using scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the composite with 3DOM structure exhibited remarkable desulfurization performance at room temperature and the enhancement of reactive adsorption of hydrogen sulfide was attributed to the unique structure features of 3DOM composites; high surface areas, nanocrystalline ZnO and the well-ordered interconnected macroporous with abundant mesopores. The introduction of silica could be conducive to support the 3DOM structure and the high dispersion of zinc oxide. Moisture in the H2S stream plays a crucial role in the removal process. The effects of Zn/Si ratio and the calcination temperature of 3DOM composites on H2S removal were studied. It demonstrated that the highest content of ZnO could reach up to 73 wt % and the optimum calcination temperature was 500 °C. The multiple adsorption/regeneration cycles showed that the 3DOM ZnO-SiO2 sorbent is stable and the sulfur capacity can still reach 67.4% of that of the fresh sorbent at the fifth cycle. These results indicate that 3DOM ZnO-SiO2 composites will be a promising sorbent for H2S removal at room temperature.

15.
Environ Sci Technol ; 47(9): 4859-65, 2013 May 07.
Article in English | MEDLINE | ID: mdl-23528010

ABSTRACT

A series of iron oxide sorbents with novel structures of three-dimensionally ordered macropores (3DOM), ranging in size from 60 to 550 nm, were fabricated and creatively used as sorbents for the removal of H2S at medium temperatures of 300-350 °C. Evaluation tests using thermogravimetric analysis (TGA) and a fixed-bed reactor showed that, in comparison to the iron oxide sorbent prepared by a conventional mixing method, the fabricated iron oxide sorbent with a 3DOM structure exhibited much higher reactivity and efficiency, as well as high sorbent utilization with low regeneration temperature. The excellent performance of 3DOM iron oxide as a sulfur sorbent is attributed to its special texture, i.e., the open and interconnected macroporous, large surface area, and nanoparticles of iron oxide, which are revealed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption techniques. The investigation results of the pore effect on the performance of the sorbent show that sorbents with pores size around 150 nm in diameter revealed the best performance. The reason is that pores of this size are large enough to allow gas to pass through even if the channel is partially blocked during the reaction process while remaining a large surface area that can provide more active sites for the reaction.


Subject(s)
Ferric Compounds/chemistry , Hot Temperature , Hydrogen Sulfide/isolation & purification , Adsorption , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , X-Ray Diffraction
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