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1.
J Colloid Interface Sci ; 606(Pt 2): 1662-1672, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34507166

RESUMO

Efficient and durable non-precious catalyst for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is pivotal for practical water electrolysis toward clean hydrogen fuel. Herein, a molybdenum oxide-FeCoCu alloy hybrid (MoOx-FeCoCu) catalyst was designed by polyoxometallate (POM) molecular cluster mediated solvothermal alcoholysis and ammonolysis of metal salts followed by pyrolytic reduction treatment. The HER efficiency is substantially enhanced by the ternary alloy component, which is more close to the benchmark Pt/C catalyst, and the HER catalytic stability is also superior to Pt/C catalyst. Moreover, the MoOx-FeCoCu demonstrates high catalytic efficiency and rather good durability for OER. Benefitted by the bifunctional catalytic behaviors for HER and OER, the symmetric water electrolyzer based on the MoOx-FeCoCu electrode requires a low driving voltage of 1.69 V to deliver a response current density of 10 mA cm-2, which is comparable to that based on the benchmark Pt/C HER cathode and RuO2 OER anode. The current work offers a feasible way to design efficient bifunctional catalyst for water electrolysis via POM mediated co-assembly and calcination treatment.

2.
ACS Omega ; 6(45): 30526-30533, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34805681

RESUMO

It is of great importance to understand the thermal properties of MoSe2 films for electronic and optoelectronic applications. In this work, large-area polycrystalline MoSe2 films are prepared using a low-cost, controllable, large-scale, and repeatable chemical vapor deposition method, which facilitates direct device fabrication. Raman spectra and X-ray diffraction patterns indicate a hexagonal (2H) crystal structure of the MoSe2 film. Ellipsometric spectra analysis indicates that the optical band gap of the MoSe2 film is estimated to be ∼1.23 eV. From the analysis of the temperature-dependent and laser-power-dependent Raman spectra, the thermal conductivity of the suspended MoSe2 films is found to be ∼28.48 W/(m·K) at room temperature. The results can provide useful guidance for an effective thermal management of large-area polycrystalline MoSe2-based electronic and optoelectronic devices.

3.
Mater Horiz ; 8(7): 1985-1997, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34846475

RESUMO

Flexoelectricity and photoelectricity with their coupled effect (the so-called flexo-photoelectronic effect), are of increasing interest in the study of electronics and optoelectronics in van der Waals layered semiconductors. However, the related device design is severely restricted owing to the ambiguous underlying physical nature of flexo-photoelectronic effects originating from the co-manipulation of light and strain-gradients. Here, flexoelectric polarization and the flexo-photoelectronic effect of few-layered semiconductors have been multi-dimensionally investigated from high-resolution microscopic characterization on the nanoscale, physics analysis, and deriving a device design. We found that two back-to-back built-in electric fields form in bent InSe and WSe2, and greatly modulate the transport behaviors of photogenerated carriers, further facilitating the separation of photogenerated electron-hole pairs and trapping the holes/electrons in InSe or WSe2 channels, recorded in realtime by a home-made technique of lighting Kelvin probe force microscopy (KPFM). The slow release of trapped carriers contributes to the photoconductance relaxation after illumination. Utilizing the photoconductance relaxation, a light-stimulated artificial synapse based on the flexo-photoelectronic effect of bent InSe has been achieved. Significantly, all the pair-pulse facilitation (PPF) behavior, spike frequency-dependent excitatory post-synaptic current (EPSC) and the transition from short-term memory (STM) to long-term memory (LTM) have been successfully realized in this artificial synapse. This work adds to the investigation of flexo-photoelectronic effects on 2D optoelectronics, and moves towards the development of 2D neuromorphic electronics.

4.
Proc Natl Acad Sci U S A ; 118(49)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34845011

RESUMO

Due to structural incommensurability, the emergence of a quasicrystal from a crystalline phase represents a challenge to computational physics. Here, the nucleation of quasicrystals is investigated by using an efficient computational method applied to a Landau free-energy functional. Specifically, transition pathways connecting different local minima of the Lifshitz-Petrich model are obtained by using the high-index saddle dynamics. Saddle points on these paths are identified as the critical nuclei of the 6-fold crystals and 12-fold quasicrystals. The results reveal that phase transitions between the crystalline and quasicrystalline phases could follow two possible pathways, corresponding to a one-stage phase transition and a two-stage phase transition involving a metastable lamellar quasicrystalline state, respectively.

5.
PhytoKeys ; 185: 43-53, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34819780

RESUMO

Lespedezadanxiaensis (Fabaceae), a new species from Danxiashan National Nature Reserve in Guangdong Province, is described and illustrated. The new species is morphologically similar to Lespedezapilosa, but it can be easily distinguished by its thin leathery leaflets and long peduncles. Phylogenetic analysis based on ITS confirmed that the new species belongs to Lespedezasubg.Macrolespedeza. The new species is the first known species of Lespedeza endemic to Danxia landform and is currently only known from Mount Danxia, Guangdong.

6.
Waste Manag ; 137: 50-60, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34731680

RESUMO

A significant amount of coal fly ash is generated and this type of waste material causes severe environmental hazards. Metal (Al and Fe) extraction from coal fly ash is beneficial to the resource utilization of waste coal fly ash. However, the coexistence of Al and Fe in coal fly ash means that the separation of Al and Fe is required, which is a key and difficult step to prepare high value-added products from coal fly ash. This work presents a novel electrolysis method to alter the charge sequence of Al3+, Fe3+, and H2O, leading to a process different from their natural tendency for simultaneous separation of Fe3+ and Al3+, and extraction of Fe. The single iron removal efficiency was 43.48%, and the aluminum extraction efficiency was <0.30% under optimal conditions. The iron product had a purity of 98.3 wt% Fe, 0.45 wt% Al, and 0.18 wt% S. This process occurs without chemical additions and expensive membranes, avoiding impurity introduction, slag generation, and membrane limitations. Fe(s), H2(g), Al2(SO4)3(aq), and O2(g) are the main products during the electrolysis. Flake Fe is selectively produced instead of colloidal Fe(OH)3. Fe is a magnetic substance and is easier to remove from the solution by magnets than colloidal Fe(OH)3. H2 is a green fuel. Wastewater (Al2(SO4)3(aq)) can be directly used to further extract alumina. Therefore, this study provides an alternative method of zero pollution discharge for simultaneous separation of Fe3+ and Al3+, and extraction of Fe from coal fly ash leachate.

7.
Chemistry ; 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34735034

RESUMO

Six novel benzimidazole-based D-π-A compounds 4 a-4 f were concisely synthesized by attaching different donor/acceptor units to the skeleton of 1,3-bis(1H-benzimidazol-2-yl)benzene on its 5-position through an ethynyl link. Due to the twisted conformation and effective conjugation structure, these dual-state emission (DSE) molecules show intense and multifarious photoluminescence, and their fluorescence quantum yields in solution and solid state can be up to 96.16 and 69.82 %, respectively. Especially, for excellent photostability, obvious solvatofluorochromic and extraordinary wide range of solvent compatibility, DSE molecule 4 a is a multifunctional fluorescent probe for the visual detection of nitroaromatic compounds (NACs) with the limit of detection as low as 10-7 M. The quenching mechanism has been proved as the results of photoinduced electron transfer and fluorescence resonance energy transfer processes. Importantly, probe 4 a can sensitively detect NACs not only in real water samples, but also on 4 a-coated strips and 4 a@PBAT thin films.

8.
Chemosphere ; : 132832, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34762879

RESUMO

Recovery of phosphorus (P) from wastewater has led to growing public concern considering its scarcity and future availability as well as its detrimental environmental impacts. However, the recovered P is inevitably contaminated with co-existing antibiotics like tetracycline (TC) and sulfamethazine (SMT) which will pose serious risks to the health of human and animals after being spread to the environment. In this study, we propose a novel scheme that can recover P from synthetic wastewater and at the same time degrade the co-existing antibiotics. To achieve such a goal, a series of biochar (BC) were prepared from calcination of waste sludge and were used both as the adsorbent for P recovery and as the catalyst for peroxymonosulfate (PMS) activation and antibiotic degradation. Results showed that the sludge source (i.e. Sm: municipal sludge, Sp: paper mill sludge), calcination atmosphere (i.e. air-deficient, N2, vacuum) and temperature (i.e. 600 and 800 °C) exhibited significant influence on P adsorption capacity. Generally, the BC calcined in N2 showed better P uptake, and increase of calcination temperature from 600 °C to 800 °C could further improve P uptake. Though BCp-N-600 (prepared from Sp in N2 at 600 °C) showed faster and higher P uptake (56.3 mg/g) than its counterpart BCm-N-600 (33.2 mg/g), BCm-N-600 showed stronger catalytic activity and more stable performance in the complex pollutant system (P + SMT). It was proposed that P was recovered primarily through the chemisorption and precipitation mechanism, while SMT was nearly completely degraded primarily by the ROS generated from PMS activation.

9.
Mol Phylogenet Evol ; 167: 107362, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775057

RESUMO

Delimitation of the tribe Arethuseae has varied considerably since it was first defined. The relationships within Arethuseae, particularly within the subtribe Arethusinae, remain poorly elucidated. In this study, we reconstructed the phylogeny of Arethuseae, using six plastid markers (matK, ycf1, rbcL rpoc1, rpl32-trnL and trnL-F) from 83 taxa. The ancestral state reconstruction of 11 selected morphological characters was also conducted to identify synapomorphies and assess potential evolutionary transitions. Morphological character comparision between the distinct species Bletilla foliosa and other species are conducted. Our results unequivocally supported the monophyly of Arethuseae, which included highly supported clades and a clear synapomorphy of non-trichome-like lamellae. Furthermore, B. foliosa formed a separate clade in the subtribe Arethusinae, instead of clustering with the other Bletilla species in the subtribe Coelogyninae. The morphological characters comparision further showed that the B. foliosa clade could be distinguished from other genera in Arethuseae by multiple characters, including presence of lateral inflorescence, three lamellae with trichome-like apex and four pollinia. In light of these molecular and morphological evidences, we propose Mengzia as a new genus to accommodate B. foliosa and accordingly provide descriptions of this new genus and combination.

10.
Zhongguo Zhong Yao Za Zhi ; 46(19): 5080-5087, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34738404

RESUMO

The present study explored the mechanism of action of Gynostemma pentaphyllum in the treatment of metabolism associa-ted fatty liver disease(MAFLD) by network pharmacology and molecular docking. The main active components and action targets of G. pentaphyllum were collected from TCMSP. Disease-related targets were obtained from GeneCards, OMIM and TTD, and the common targets of the three databases were screened out, which were converted to the genes with standard names by UniProt. The drug-disease common target genes were obtained through Venn tool and uploaded to STRING for the construction of the protein-protein interaction(PPI) network. Cytoscape was used to construct and analyze the drug-active component-common target-disease network. The gene ontology(GO) analysis and Kyoto encyclopedia of genes and genomes(KEGG) pathway enrichment analysis were performed on the common targets by DAVID. Pymol was adopted to perform molecular docking of active components and the common targets and predict their binding ability. Twenty-four active components(such as gypenosides, quercetin and sitosterol) of G. pentaphyllum were screened out. Ninety-two targets were obtained and 54 common targets were identified. Key targets included TNF, IL6, PTGS2, TP53, CCL2 and VEGFA. GO analysis on biological processes, molecular functions and cellular components and KEGG pathway analysis were performed, and the results indicated that NF-κB, PI3 K-Akt, TNF and HIF-1 signaling pathways were mainly involved. Molecular docking results showed that gypenosides and quercetin had a strong binding ability to TNF, IL6 and PTGS2. The findings of this study revealed that the therapeutic efficacy of G. pentaphyllum on MAFLD might be achieved by resisting inflammation and oxidative stress and improving insulin resistance, providing ideas and a theoretical basis for the development and application of G. pentaphyllum in the treatment of MAFLD.


Assuntos
Medicamentos de Ervas Chinesas , Hepatopatias , Gynostemma , Simulação de Acoplamento Molecular , Transdução de Sinais
11.
ACS Nano ; 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34739207

RESUMO

Dental diseases resulting from movement disorders and volatile gases are very common. The classic method for detecting occlusal force is effective; however, its function is one-time rather than real-time monitoring, and the technology is very time-consuming. Herein, we report a multifunctional, flexible, and degradable bacterial cellulose/Ti3C2Tx MXene bioaerogel for the accurate detection of occlusal force and early diagnosis of periodontal diseases. Combining the mechanical properties of MXene and the abundant functional groups of bacterial cellulose, 3D porous bioaerogels exhibit both pressure-sensitive and ammonia (NH3)-sensitive responses. By integrating these substances into a flexible array, the resulting device can distinguish the intensity, location, and even the time sequence of the occlusion force; moreover, it can provide NH3 gas and occlusion force response signals. Therefore, this technology is promising for both disease diagnosis and oral health. In addition, the introduction of a renewable biomaterial allows the bioaerogel to degrade completely using a low-concentration hydrogen peroxide solution, making the device environmentally friendly and satisfying the demands for sustainable development.

12.
J Clin Invest ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34752417

RESUMO

Acute myocardial infarction (AMI) induces blood leukocytosis, which correlates inversely with patient survival. The molecular mechanisms leading to leukocytosis in the infarcted heart, remain poorly understood. Using an AMI mouse model, we identified gasdermin D (GSDMD) in activated leukocytes early in AMI. We demonstrated that GSDMD is required for enhanced early mobilization of neutrophils to the infarcted heart. Loss of GSDMD resulted in attenuated IL-1ß release from neutrophils and subsequent decreased neutrophils and monocytes in the infarcted heart. Knockout of GSDMD in mice significantly reduced infarct size, improved cardiac function, and increased survival post AMI. Through a series of bone marrow transplantation studies and leukocytes depletion experiments, we further clarified that excessive bone marrow derived and GSDMD-dependent early neutrophil production and mobilization (24 hours post AMI), contributed to the detrimental immunopathology after AMI. Pharmacological inhibition of GSDMD also conferred cardioprotection post AMI, through reduction of scar size and enhancement of heart function. Our study provides new mechanistic insights into molecular regulation of neutrophil generation and mobilization after AMI, and supports GSDMD as a new target for improved ventricular remodeling and reduced heart failure after AMI.

13.
Front Pharmacol ; 12: 752148, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603062

RESUMO

Background: Alcoholic liver disease (ALD) caused by chronic ethanol overconsumption is a common type of liver disease with a severe mortality burden throughout the world. The pathogenesis of ALD is complex, and no effective clinical treatment for the disease has advanced so far. Prolonged alcohol abstinence is the most effective therapy to attenuate the clinical course of ALD and even reverse liver damage. However, the molecular mechanisms involved in alcohol abstinence-improved recovery from alcoholic fatty liver remain unclear. This study aims to systematically evaluate the beneficial effect of alcohol abstinence on pathological changes in ALD. Methods: Using the Lieber-DeCarli mouse model of ALD, we analysed whether 1-week alcohol withdrawal reversed alcohol-induced detrimental alterations, including oxidative stress, liver injury, lipids metabolism, and hepatic inflammation, by detecting biomarkers and potential targets. Results: Alcohol withdrawal ameliorated alcohol-induced hepatic steatosis by improving liver lipid metabolism reprogramming via upregulating phosphorylated 5'-AMP -activated protein kinase (p-AMPK), peroxisome proliferator-activated receptor-α (PPAR-α), and carnitine palmitoyltransferase-1 (CPT-1), and downregulating fatty acid synthase (FAS) and diacylglycerol acyltransferase-2 (DGAT-2). The activities of antioxidant enzymes, including superoxide dismutase (SOD) and glutathione peroxidase (GSH-px), were significantly enhanced by alcohol withdrawal. Importantly, the abstinence recovered alcohol-fed induced liver injury, as evidenced by the improvements in haematoxylin and eosin (H&E) staining, plasma alanine aminotransferase (ALT) levels, and liver weight/body weight ratio. Alcohol-stimulated toll-like receptor 4/mitogen-activated protein kinases (TLR4/MAPKs) were significantly reversed by alcohol withdrawal, which might mechanistically contribute to the amelioration of liver injury. Accordingly, the hepatic inflammatory factor represented by tumour necrosis factor-alpha (TNF-α) was improved by alcohol abstinence. Conclusion: In summary, we reported that alcohol withdrawal effectively restored hepatic lipid metabolism and reversed liver injury and inflammation by improving metabolism reprogramming. These findings enhanced our understanding of the biological mechanisms involved in the beneficial role of alcohol abstinence as an effective treatment for ALD.

14.
Water Res ; 206: 117762, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34678700

RESUMO

Rare information is available on fouling behavior of customized nanofiltration (NF) membrane evoked by pharmaceutically active compounds (PhACs) under real multiple influent matrices pretreated by ultrafiltration module beforehand. To this end, a novel tight NF membrane with excellent perm-selectivity and antiadhesion was fabricated and used to assess its separation performance/mechanism and fouling behavior to a broad range of small molecular PhACs in the context. The adsorption ratio results revealed that the affinities between five selected PhACs and the customized nanocomposite membrane surface were all much weaker (below 5.5%) than the solute-solute interacting forces (between 23.6 and 83.2%), whether for natural or synthetic complex micropollutants. The predominant membrane fouling could be interpreted by the incomplete blocking model in the permeation of both influent conditions. For neat nanocomposite membrane, the order of critical factors important on separation mechanism was electrostatic effect, adsorption and steric hindrance. The fouling layer seemed to act as a secondary separating layer for those negatively charged or hydrophilic PhACs, but showed the cake enhanced concentration polarization effect for the neutral and hydrophobic ones. This study provides valuable insights for defining PhACs fate and NF membrane fouling behavior to fit increasingly stringent criteria for wastewater treatment.


Assuntos
Nanocompostos , Purificação da Água , Adsorção , Membranas Artificiais , Ultrafiltração
15.
Adv Sci (Weinh) ; : e2103257, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34713981

RESUMO

Wearable sweat sensors have received significant research interest and have become popular as sweat contains considerable health information about physiological and psychological states. However, measured biomarker concentrations vary with sweat rates, which has a significant effect on the accuracy and reliability of sweat biosensors. Wearable sweat loss measuring devices (SLMDs) have recently been proposed to overcome the limitations of biomarker tracking and reduce inter- and intraindividual variability. In addition, they offer substantial potential for monitoring human body homeostasis, because sweat loss plays an indispensable role in thermoregulation and skin hydration. Previous studies have not carried out a comprehensive and systematic review of the principles, importance, and development of wearable SLMDs. This paper reviews wearable SLMDs with a new health perspective from the role of sweat loss to advanced mechanisms and designs. Two types of sweat and their measurement significance for practical applications are highlighted. Then, a comprehensive review of advances in different wearable SLMDs based on hygrometers, absorbent materials, and microfluidics is presented by describing their respective device architectures, present situations, and future directions. Finally, concluding remarks on opportunities for future application fields and challenges for future sweat sensing are presented.

16.
ACS Appl Mater Interfaces ; 13(42): 50132-50140, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34662123

RESUMO

The simulation of human brain neurons by synaptic devices could be an effective strategy to break through the notorious "von Neumann Bottleneck" and "Memory Wall". Herein, opto-electronic synapses based on layered hafnium disulfide (HfS2) transistors have been investigated. The basic functions of biological synapses are realized and optimized by modifying pulsed light conditions. Furthermore, 2 × 2 pixel imaging chips have also been developed. Two-pixel visual information is illuminated on diagonal pixels of the imaging array by applying light pulses (λ = 405 nm) with different pulse frequencies, mimicking short-term memory and long-term memory characteristics of the human vision system. In addition, an optically/electrically driven neuromorphic computation is demonstrated by machine learning to classify hand-written numbers with an accuracy of about 88.5%. This work will be an important step toward an artificial neural network comprising neuromorphic vision sensing and training functions.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34706192

RESUMO

Graphene-based catalysts have been widely applied for catalytic ozonation. However, as it is difficult to obtain graphene with high structural precision, it is currently unfeasible to comprehend the relationships between the intrinsic structure of the layered carbon catalysts with its catalytic activities. Here, an advanced plasma-assisted etch strategy was used to fine tune the ozonation activity of monolayered graphene films by tailoring the defect types. Raman mapping indicated that the defects of the as-prepared monolayered graphene films were predominantly sp3, vacancy, and boundary-type defects, respectively. The roles and contributions of these active defects in manipulating the oxidative potential of monolayered graphene films were revealed by quenching experiments, electron paramagnetic resonance results, and density functional theory calculations. The catalytic results showed that the monolayered graphene films with boundary-like defects exhibited the best catalytic performance toward the degradation of sulfamethoxazole. This work contributes new insights into the design of high-efficiency carbonaceous catalysts by structuring additional defective sites.

18.
Biomed Mater ; 16(6)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34670204

RESUMO

Collagen and chitosan are two different kinds of natural biodegradable polymers commonly used in the regeneration of bone defects. Mesoporous bioactive glass (MBG) is a type of favorable bone filler which can effectively constitute an enlarged microenvironment to facilitate an exchange of important factors between the cells and scaffolds. Here we prepared a collagen-chitosan-MBG (C-C-MBG) scaffold which displayed significantly increased proliferation, differentiation and mineralization in bone mesenchymal stem cells (BMSCs). Additionally, we found that the scaffold can stimulate extra-cellular signal regulated kinase 1/2 (Erk1/2) activated Runx2 pathway, which is the predominant signaling pathway involved in osteoblast differentiation. Consistently, we observed that the scaffold can markedly enhance the expression ofType I collagen, Osteopontin(Opn), andRunx2, which are important osteoblastic marker genes implicated in the process of osteoblast differentiation. Therefore, we conclude that the composite scaffold can significantly promote the differentiation of BMSCs into osteoblasts by activating Erk1/2-Runx2 pathway. Our finding thereby implies that the C-C-MBG scaffold can possibly act as a potential biomaterial in the bone regeneration.

19.
Front Oncol ; 11: 754221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692540

RESUMO

Objective: The present study was designed to investigate the role of the chemokine CXCL7 in angiogenesis and explore its prognostic value in colorectal cancer (CRC). Methods: A total of 160 CRC patients who had undergone surgery were included in this study, and staged according to the guidelines of the AJCC, 7th Edition. Expression of CXCL7 and VEGF was detected by immunohistochemical (IHC) staining and divided into high and low expression subgroups. The correlation between CXCL7 and VEGF expression was evaluated by Spearman's rank-correlation coefficient. Prognosis based on CXCL7 and VEGF was evaluated using the Cox proportional hazards regression model and a nomogram of 5-year overall survival (OS) time. Results: CXCL7 was highly expressed in tumor tissues (65.63% vs 25.00% in paracancerous tissue, P < 0.001), as was VEGF. CXCL7 and VEGF expression correlated well with N and TNM stage cancers (all P < 0.001). Importantly, CXCL7 was positively correlated with VEGF expression in CRC tissues. CXCL7 was an independent predictor of poor OS of CRC patients (HR = 2.216, 95% CI: 1.069-4.593, P = 0.032), and co-expression of CXCL7 and VEGF of predicted poor OS of 56.96 months. Conclusion: Expression of CXCL7 correlated with VEGF and was associated with poor clinical outcomes in CRC patients.

20.
Anal Chem ; 93(43): 14471-14480, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34693710

RESUMO

α-Naphthyl acetate esterase (α-NAE) and acid α-naphthyl acetate esterase (ANAE), a class of special esterases, are important for lymphocyte typing and immunocompetence-monitoring. As such, the simultaneous detection of α-NAE and ANAE has become a target to effectively improve the accuracy in lymphocyte typing. Therefore, we developed a dual-factor synergistically activated ESIPT-based probe (HBT-NA) to detect α-NAE and ANAE sensitively, rapidly, and simultaneously in a differential manner. HBT-NA exhibits differential fluorescence signal outputs toward small changes of α-NAE and ANAE activities. HBT-NA displays a weak fluorescence signal at 392 nm over a pH range from 6.0 to 7.4. However, when it interacts with α-NAE (0-25 U) at pH = 7.4, the fluorescence intensity at 392 nm enhanced linearly within 60 s (F392 nm/F0392 nm = 0.042 Cα-NAE + 1.1, R2 = 0.99). Furthermore, HBT-NA emits ratiometric fluorescence signals (F505 nm/F392 nm) for ANAE (0-25 U) at pH = 6.0 within 2.0 min, exhibiting a good linear relationship (F505 nm/F392 nm = 0.83CANAE - 1.75, R2 = 0.99). The differential fluorescence signals can be used to simultaneously detect the activities of α-NAE and ANAE in solutions and complex living organisms. More importantly, based on the differential fluorescence signals toward α-NAE and ANAE, T lymphocytes and B lymphocytes could be successfully typed and differentiated among nontyped lymphocytes, facilitating the real-time evaluation of their immune functions using flow cytometry. Hence, HBT-NA could be used for the ultrasensitive detection of the enzyme activities of α-NAE and ANAE, the real-time precise typing of lymphocytes, and the monitoring of immunocompetence.


Assuntos
Naftol AS D Esterase , Linfócitos T , Linfócitos B , Naftóis
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