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1.
Bioorg Chem ; : 105484, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34836642

RESUMO

The irregular viscosity in the mitochondrial can induce mitochondrial dysfunction. The content of peroxynitrite (ONOO-) is related to various physiological and pathological processes. However, many mitochondrial probes only realized the detection of viscosity or ONOO- in single channel, thus it is necessary to explore single fluorescence probe for dual-detecting mitochondrial viscosity and ONOO-. In this work, we designed and synthesized a novel fluorescence probe (PV) for dual-detecting viscosity and ONOO-, which was composed by intergrating a ONOO-- responsive arlyboronate with a twisting intramolecular charge transfer (TICT) mechanism and possessed the mitochondria-targeting ability due to its pyridinium cation. PV exhibited a significant increase in viscosity with red emission at 582 nm and high sensitivity to ONOO- levels with yellow emission at 507 nm. PV was also applied to living systems (including living cells and zebrafish) for viscosity and ONOO- detection using two different channels. Moreover, the ability of PV to track mitophagy may make ONOO- a powerful tool for its role in mitophagy.

2.
Sci Total Environ ; 800: 149371, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426360

RESUMO

Understanding the role of reactive oxygen species (ROS) is essential to elucidate the mechanism of contaminants degradation in in-situ chemical oxidation (ISCO). In this study, compound specific isotope analysis (CSIA) and radicals quenching methods were integrated to investigate the roles of hydroxyl radical (HO), sulfate radical (SO4-), and superoxide radical (O2-) on trichloroethene (TCE) degradation during persulfate (PS) activated with base. The carbon isotope fractionation of TCE was found to be dependent of the base:PS ratios, yielding carbon enrichment factors (ε values) from -9.8 ± 0.5‰ to -16.7 ± 1.0‰ at base:PS molar ratios between 0.5:1 and 10:1, which was attributed to multi-pathways degradation of TCE by multiple ROS. The expected ε value (-31.6 ± 1.6‰) for TCE degradation via O2- attacking pathway, was more negative than those values via SO4- or HO pathways. The relative contributions of HO, SO4- and O2- for TCE degradation during base activated PS were estimated with observed ε values. HO and O2- were the predominant ROS for TCE degradation (with the relative contribution of 55-69% and 22-45%, respectively) in base activated PS. This work highlights the prospect of CSIA application for identifying degradation pathways of contaminants with ROS in environment.


Assuntos
Tricloroetileno , Poluentes Químicos da Água , Isótopos de Carbono , Fracionamento Químico , Oxirredução , Espécies Reativas de Oxigênio , Poluentes Químicos da Água/análise
3.
Talanta ; 233: 122593, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215082

RESUMO

The latent fingerprints (LFPs) at the crime scene are unique and stable, which are considered as an important clue in criminal justice and forensic identification. Herein, a butterfly-shaped molecule DPTS with solid fluorescence plus excited-state intramolecular proton transfer (ESIPT) properties was used to develop for enhancing the visualization of the LFPs. Considering the solid fluorescence of DPTS, the color and efficiency of DPTS with a large Stokes shift (216 nm) can be tuned by changing the morphology of its aggregates, and gradually red-shifted (green-yellow-red) with increasing water content. Furthermore, its effectiveness for the detection of LFPs was demonstrated on various different substrates including paper box, tinfoil and weighting paper. The emissive fingerprint of DPTS obtained gave good fluorescence images with high contrast and resolution such as the core, delta, bifurcation, ridge termination, independent ridge and pores. Caging of the phenol donor of DPTS with a sensitive biomarker group provided DPTS-ONOO-, which had high sensitive with detection limit of 5 nM and the quantification limit of 21 nM toward ONOO-. Modularly derived DPTS-ONOO- was synthesized and demonstrated specific fluorescence imaging of exogenous and endogenous peroxynitrite (ONOO-) in living macrophage cells.


Assuntos
Corantes Fluorescentes , Prótons , Ácido Peroxinitroso , Fenol , Fenóis
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120044, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118522

RESUMO

Fluorescent probes have contributed greatly to our understanding of the biological role of peroxynitrite (ONOO-). The ONOO- fluorescence probe characterized by the arlyboronate received a moderate opening fluorescence response, and the borate-masked probe significantly increased the sensitivity of ONOO-. Thus, two simple fluorescent probes (ADB and ANB) with the recognition receptor of phenyl boronate moiety were constructed for the detection of ONOO-. The change of emission spectrum was affected differently by the electron donating (or withdrawing) of the substituents. ANB was shown to have a low sensitivity and quantum yield towards ONOO- in aqueous solution, whereas ADB with aggregation-induced emission (AIE) process exhibited not only good sensitivity for ONOO- with a detection limit of 75 nM, but also ADB could be used to quantitative detecting ONOO- in response to concentrations of ONOO- within 20 s. Importantly, ADB had good performance for the detection of exogenous ONOO- in the RAW 264.7 cells.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Animais , Boratos , Camundongos , Imagem Óptica , Células RAW 264.7
5.
J Colloid Interface Sci ; 601: 114-123, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34058547

RESUMO

The rational design of the surface structure and morphology characteristics of the catalyst at atomic level are the key to improve the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in lithium-oxygen (Li-O2) battery. Here a series of cobalt phosphide (CoP) electrocatalysts with a variety of index facets are successfully prepared including concave polyhedrons CoP exposing with (211) crystal planes (CoP CPHs) spherical nanoparticles CoP exposed with (011) crystal planes and polyhedron particles CoP exposing with (011) and (111) crystal planes. The results show that CoP CPHs based Li-O2 battery presents a large discharge capacity of 33743 mA h g-1 at current density of 50 mA g-1 and a remarkable long cycle life of up to 950 h. The experimental results demonstrates that the CoP CPHs electrode exposing with high-index (211) facets based Li-O2 battery exhibits an extremely low overpotential (0.67 V) ultrahigh specific capacity (33743 mAh g-1) and remarkable long-term stability of up to 950 h. Most importantly density functional theory (DFT) calculations demonstrate the excellent electrocatalytic activity of high-index (211) facets as compared to the low-index (011) and (111) planes are because of the existence of large density of atomic steps edge ledge sites and kinks which supply a wide space for breaking chemical bonds and increasing the reaction activity for oxygen electrode.

6.
J Agric Food Chem ; 69(9): 2836-2844, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33621092

RESUMO

In this work, we synthesized carbon nanodots (CNDs) by a one-pot hydrothermal method to carbonize precursors of dry carnation petals and polyethylenimine. The obtained CNDs possess favorable photostability, good biocompatibility, and excellent water solubility, which can serve as a dual-responsive nanosensor for the determination of vitamin B2 (VB2) and pH. A unique ratiometric fluorescence resonance energy transfer probe was developed through a strong interaction between VB2 and surface moieties of CNDs. CNDs emitted at 470 nm; however, in the presence of VB2, an enhanced emission peak was clearly observed at 532 nm. The value of I532/I470 exhibits a stable response to the VB2 concentration from 0.35 to 35.9 µM with a detection limit of 37.2 nM, which has been used for VB2 detection in food and medicine samples and ratiometric imaging of VB2 in living cells with satisfying performance. In addition, the proposed CNDs also displayed pH-sensitive behavior and can be a turn-off fluorescent sensor to monitor pH. The fluorescent intensity at 470 nm is a good linear response against pH values from 3.6 to 8, affording the capability as a single-emissive nanoprobe for intracellular pH sensing.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Riboflavina , Vitaminas
7.
Biomater Sci ; 9(6): 2255-2261, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33533378

RESUMO

Intracellular pH and hypochlorite (ClO-) concentration play an important role in life activities, so there is an urgent need to develop a valid strategy to monitor pH and ClO- in biological systems with high sensitivity and specificity. In this study, we report long-wavelength emission nitrogen-doped carbon dots (N-CDs) and their potential applications in intracellular pH variation, ClO- sensing and cell imaging. The N-CDs were prepared via a facile one-pot hydrothermal method of neutral red (NR) and glutamine (Gln). N-CDs exhibited a pH-sensitive response in the range of 4.0-9.0 and a good linear relationship in the range of 5.6-7.4, which indicated that N-CDs are an ideal agent for monitoring pH fluctuations in living cells. In addition, ClO- was capable of reducing the photoluminescence of N-CDs based on static quenching. The linear range is 1.5-112.5 µM and 112.5-187.5 µM, and the LOD is 0.27 µM. Besides, the as-fabricated N-CDs have been smoothly achieved to monitor pH and ClO- in PC-12 living cells due to their great biocompatibility and lower cytotoxicity, demonstrating their promising applications in the biomedical field. Compared with other CD-based methods, the as-proposed N-CDs have a longer fluorescence emission, which makes them potentially valuable in biological systems. The results pave a way towards the construction of long-wavelength carbon-based nanomaterials for fluorescence sensing and cell imaging.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Ácido Hipocloroso , Nitrogênio
8.
Analyst ; 146(2): 509-514, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33210693

RESUMO

Phenol fluorophores are a large family of fluorophores, which have attracted more and more attention in the design of probes. Using the self-assembly of aromatic boronic acid with Alizarin Red S (ARS) and Gallein (GAL), the novel chemosensors ARS-CBA and GAL-CBA were provided for hydrogen peroxide (H2O2), which demonstrated their ability to detect H2O2 with indicator displacement assay (IDA) by colorimetric and electrochemical measurements. After ARS-CBA and GAL-CBA reacted with H2O2, the systems displayed a red-shifted visible color change in aqueous media and off-on electrochemical signals showing generation of phenol. The chemosensor ARS-CBA also had good performance in fluorometric measurements and turn-off fluorescent response indicated removal of aromatic boronic acid. In addition, a designed near-infrared (NIR) dual-modal fluorescent probe alizarin blue S (ABS) was used for peroxynitrite (ONOO-) with a visible colorimetric change in dimethyl sulfoxide (DMSO) and "on-off" fluorescent response indicating the oxidation of hydroxyl. The flexible Phenol fluorophores are allowed to prepare multiple fluorescent probes towards H2O2 or ONOO- for environmental and physiological applications.

9.
Mater Sci Eng C Mater Biol Appl ; 118: 111478, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255057

RESUMO

The fluorescent boron, nitrogen and sulfur co-doped carbon dots (BNSCDs) were prepared by simple hydrothermal reaction of 4-carboxyphenylboronic acid and 2,5-diaminobenzenesulfonic acid at 200 °C for 8 h. The fluorescence of the BNSCDs could be quenched by Fe3+ based on the electron transfer between Fe3+ and BNSCDs, so a label-free, good selectivity and high sensitivity method for Fe3+determination was established with linear range and LOD of 1.5-692 µmol/L and 87 nmol/L, respectively. And then the fluorescent probe was employed for detection of Fe3+ in tap water, coal gangue, fly ash and food samples successfully. Moreover, the as-prepared BNSCDs could serve as a novel pH fluorescent probe in the range of pH 1.60-7.00, which could be attributed to the proton transfer of carboxyl groups on the surface of BNSCDs. More importantly, the pH fluorescent probe possesses fast, real-time and low toxicity, applying for intracellular pH fluorescence imaging in HIC, HIEC, LO2 and SMMC7721 cells. In view of its simplicity, timely response and outstanding compatibility, the as-fabricated BNSCDs show the potential applications in water quality and solid waste monitoring, food detection, real-time measuring of intracellular pH change in vitro.


Assuntos
Citrus sinensis , Pontos Quânticos , Boro , Carbono , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Nitrogênio , Espectrometria de Fluorescência , Enxofre
10.
Regen Biomater ; 7(6): 597-608, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33365145

RESUMO

A nasal stent capable of preventing adhesions and inflammation is of great value in treating nasal diseases. In order to solve the problems of tissue adhesion and inflammation response, we prepared plasticized bacterial cellulose (BCG) and waterborne polyurethane (WPU) composite with antibacterial function used as a novel nasal stent. The gelation behavior of BCG could contribute to protecting the paranasal sinus mucosa; meanwhile, the WPU with improved mechanical property was aimed at supporting the narrow nasal cavity. The thickness, size and the supporting force of the nasal stent could be adjusted according to the specific conditions of the nasal. Thermogravimetric analysis, contact angle and water absorption test were applied to investigate the thermal, hydrophilic and water absorption properties of the composite materials. The composite materials loaded with poly(hexamethylene biguanide) hydrochloride maintained well antibacterial activity over 12 days. Animal experiments further revealed that the mucosal epithelium mucosae damage of BCG-WPU composite was minor compared with that of WPU. This new type of drug-loaded nasal stent can effectively address the postoperative adhesions and infections while ensuring the health of nasal mucosal, and thus has an immense clinical application prospects in treating nasal diseases.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 243: 118683, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32799185

RESUMO

In this work, a novel boronate-based fluorescent probe (FAM) for the endogenous detection of peroxynitrite (ONOO-) has been developed by using anthracycline as the fluorophore, arlyboronate as the recognition moiety, lipophilic cation as the mitochondrial targeting moiety. Upon reaction of the probe with ONOO-, the oxidation and subsequent hydrolysis of ONOO- to arlyboronate triggers quite rapid fluorescence off-on response, providing a sensitive and highly selective method for the detection of ONOO-. In addition, probe holds high sensitivity with the detection limit of 3.2 nM and excellent specificity including a series of biologically relevant reactive oxygen species. Importantly, FAM with good water solubility displays excellent performances for imaging endogenous peroxynitrite produced by RAW264.7 cells.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Animais , Células HeLa , Humanos , Camundongos , Microscopia de Fluorescência , Mitocôndrias
12.
Anal Chim Acta ; 1106: 96-102, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145860

RESUMO

Peroxynitrite (ONOO-) plays a crucial role in the regulation of diverse pathophysiological processes, and high level of ONOO- is profound association with numerous diseases. Herein, we developed an anthraquinone-based fluorescent probe L for ONOO- determination by a new recognition mechanism: amido oxidized nitroso-group by ONOO-. Probe L with amine-based recognition receptor is more selective to ONOO- than other reactive oxygen species, including H2O2 and ClO-. Furthermore, ONOO- could be rapidly detected by probe L with a Limit of Detection of 13 nM. More importantly, L could be used to monitor intracellular ONOO- in SMMC-7721 cells.


Assuntos
Antraquinonas/química , Corantes Fluorescentes/química , Ácido Peroxinitroso/análise , Linhagem Celular Tumoral , Teoria da Densidade Funcional , Humanos , Estrutura Molecular , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície
13.
Nanoscale ; 12(3): 1864-1874, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31903471

RESUMO

The degradation of oxygen electrodes caused by oxygen species in lithium-oxygen (Li-O2) batteries deteriorates their energy efficiency and cyclability and seriously hinders their commercial application. To achieve high energy efficiency and long-term cycle life, gradient-porous ultrathin FeCo2S4 nanosheets on Ni foam (FeCo2S4@Ni) were deliberately designed as a noncarbonaceous freestanding oxygen electrode for Li-O2 batteries. Notably, the gradient-porous structure in FeCo2S4@Ni can offer sufficient active sites as well as mitigate polarization caused by the mass transfer during discharge and charge. The synergistic effect of the two transition metals, Fe2+ and Co3+, optimizes their d-band electronic structure and enhances the intrinsic activity of the oxygen electrode. Benefiting from the above merits, the FeCo2S4@Ni based Li-O2 battery demonstrates greatly increased discharge capacity (8001 mA h g-1), improved rate capability (with a high capacity of 4401 mA h g-1 at 500 mA g-1), and enhanced cycling stability (with a low overpotential of below 1 V after 109 cycles). Our work demonstrates that the battery performance can be improved by regulating the structure and composition of the oxygen electrode and provides a promising strategy for developing high performance Li-O2 batteries.

14.
ACS Appl Mater Interfaces ; 11(33): 29868-29878, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31356043

RESUMO

NiFe-based transition metal oxide (NiFe-TMO) has been identified as an effective electrocatalyst for lithium-oxygen (Li-O2) batteries due to its superior catalytic activity for oxygen evolution reaction. Improving the bifunctional catalytic ability of NiFe-TMO is essential for the further performance improvement of Li-O2 batteries. Herein, we regulated the electronic structure of free-standing NiFe LDO nanosheets array via introducing foreign Co ion to improve its bifunctional catalytic activity in Li-O2 batteries. Combined with well-designed electrode architecture and the deliberately modified surface electronic structure, this strategy markedly alleviates polarization problem in terms of low overpotential (0.98 V), and the discharge voltage within 110 cycles remains stable at 2.89 V without significant attenuation. This study illustrates an intimate connection between electronic structure engineering and catalytic activity optimization that is critical for the rational design of Li-O2 batteries.

15.
Artigo em Inglês | MEDLINE | ID: mdl-30822735

RESUMO

A fluorescent sulfur and nitrogen dual-doped carbon dots (S,N-CDs) was prepared by a simple and one-step acid-base neutralization and exothermic carbonization method. Hexavalent chromium (Cr(VI)) could effectively quench the fluorescence of S,N-CDs based on inner filter effect (IFE) and dynamic quenching, whereas ascorbic acid (AA) could recover the fluorescence of S,N-CDs/Cr(VI) because of IFE weakening. So an "on-off-on" and label-free nano-probe consecutive determination of Cr(VI) and AA was constructed. This nano-probe system demonstrated excellent selectivity and sensitivity to Cr(VI) and AA with linear range of 0.065-198 µmol/L (3.38-10,296 µg/L) and 6.6-892 µmol/L (1.16-157 mg/L), respectively. Meanwhile, the as-prepared S,N-CDs possess low toxicity and could be used for multi-color cell imaging in SMMC 7721 cells. More importantly, this nano-probe was successfully employed for detection of Cr(VI) in tap water and AA in food samples. In view of its simple detection condition, rapid response, wide linear range, low detection limit and inexpensive instrument, the as-constructed nano-probe system could have a wide range of potential application, including water quality monitoring and evaluation, food inspection and testing and biomedical analysis.


Assuntos
Ácido Ascórbico/análise , Cromo/análise , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Humanos , Limite de Detecção , Modelos Lineares , Pontos Quânticos/toxicidade , Reprodutibilidade dos Testes
16.
Mater Sci Eng C Mater Biol Appl ; 80: 566-577, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28866202

RESUMO

In this study, a multilayer antibacterial film was assembled onto 316L stainless steel via mussel-inspired depositions of polydopamine (PDA) and silver (Ag) nanoparticles followed by post-modification with 1H, 1H, 2H, 2H-perfluorodecanethiol. The resulting surface exhibited excellent superhydrophobicity with hierarchical micro/nanostructures that were constructed by both PDA and Ag nanoparticles. The crystal structure and chemical composition of these surfaces were investigated using X-ray photoelectron spectroscopy (XPS) analysis. Potentiodynamic polarization measurements revealed that the corrosion resistance of the as-prepared surfaces were sequentially increased after each step of the fabrication process. Compared with the surface covered with only Ag nanoparticles, the superhydrophobic surfaces exhibited substantially enhanced antibacterial activity against the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, resulting from the synergistic antibacterial actions of the superhydrophobic surface and Ag nanoparticles. The superhydrophobic surface exhibited lower cytotoxicity, compared to the surface covered with Ag nanoparticles.


Assuntos
Antibacterianos/química , Animais , Bivalves , Corrosão , Prata , Staphylococcus aureus , Propriedades de Superfície
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