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1.
J Fluoresc ; 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37861967

RESUMO

Owing to the ultralong afterglow, room temperature decay phosphorescence nanomaterials have aroused enough attention. In the work, by simple one-pot solid-state thermal decomposition reaction, aggregate carbon dots (CDs) was prepared from trimesic and boric acid. Based on the intermolecular hydrogen bonds and intramolecular π-π stacking weak interaction from precursors, CDs was encapsulated in boron oxide matrix and formed aggregation. The aggregate state of CDs facilitated the triplet excited states (Tn), which could induce the room temperature decay phosphorescence properties. By careful investigation, under different excitation wavelengths at 254 and 365 nm, the aggregate CDs showed > 15 s and > 3 s room temperature phosphorescence emission in the naked eye, which was associated with 1516.12 ms and 718.62 ms lifetime respectively. And the aggregate CDs exhibited widespread application in encoding encryption, optical anti-counterfeiting and fingerprint identification etc. The interesting aggregate CDs revealed unexpected ultralong-afterglow room temperature decay phosphorescence properties and the work opened a window for constructing ultralong-afterglow room temperature decay phosphorescence aggregate CDs nanomaterials.

2.
J Fluoresc ; 33(6): 2241-2252, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37010649

RESUMO

Cyclodextrin (CD) is an important guest material owing to the water solubility and biocompatibility. In the paper, an organic small molecule was synthesized. According to supramolecular self-assembly, the organic molecule was bounded to the cavity of Poly ß-cyclodextrin, which was characterized by IR, SEM and TEM et al. After self-assembly interaction, the morphology has changed obviously comparing with precursors. Simultaneously, the supramolecular self-assembly complex exhibited good water solubility. Moreover, By Gaussian calculation, the high binding activity between organic molecule and cyclodextrin was confirmed. By fluorescence investigation, the supramolecular system showed high fluorescence sensing activity for Zn2+ in pure water environment, which could track the dynamic change of Zn2+ in organisms. In addition, the supramolecular system exhibited low cytotoxicity. The work provided an interesting pathway for constructing water-soluble and low cytotoxic fluorescence sensor for Zn2+.

3.
Pain Pract ; 23(1): 70-82, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35726437

RESUMO

BACKGROUND: Ultrasound-guided quadratus lumborum block (QLB) is considered a novel nerve block for postoperative pain control. However, its efficacy after urological surgery remains unclear. OBJECTIVES: The purpose of the current meta-analysis was to evaluate the effects of the QLB block versus control (placebo or no injection) on postoperative pain and other adverse outcomes after urological surgery, providing extensive evidence of whether quadratus lumborum block is suitable for pain management after urological surgery. STUDY DESIGN: Systematic review with meta-analysis of randomized clinical trials. METHODS: We searched PubMed, Cochrane Library, Embase, Web of Science, and ClinicalTrials.gov to collect studies investigating the effects of QLB on analgesia after urological surgery. The primary outcomes included visual analog scale (VAS) at rest and during movement, 24-h postoperative morphine consumption, and the incidence of postoperative nausea and vomiting (PONV). RESULTS: Overall, 13 randomized controlled trials (RCTs) were reviewed, including 751 patients who underwent urological surgery. The QLB group exhibited a lower VAS score postoperatively at rest or on movement at 0, 6, 12, and 24 h, with less 24-h postoperative morphine consumption and lower incidence of PONV. LIMITATIONS: Although the result is stable, heterogeneity exists in the current research. CONCLUSIONS: QLB exhibited a favorable effect of postoperative analgesia with reduced postoperative complications at rest or during movement after urological surgery. However, it is still a novel technology at a primary stage, which needs further research to develop.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Bloqueio Nervoso , Humanos , Anestésicos Locais , Náusea e Vômito Pós-Operatórios , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Bloqueio Nervoso/efeitos adversos , Morfina , Ultrassonografia de Intervenção
4.
J Fluoresc ; 25(3): 603-11, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25783983

RESUMO

Two simply and highly selective aluminium ion fluorescent probes based on 4-aminoantipyrine derivate have been successfully synthesized and systemically characterized, The investigation of absorption and emission spectra revealed that the compounds exhibited highly selective fluorescence behaviours toward Al(3+) in aqueous media and showed differential fluorescent emission peaks corresponding to blue and green. which resulted from different fluorophores, and the fluorescence process is attributed to the Photoinduced Electron Transfer (PET) mechanism, In addition, the association constants between sensors L1 and L2 with aluminum ion are 1.58 × 10(6) M(-1) and 8.72 × 10(6) M(-1), respectively, which were obtained by fluorescent titration experiments. Moreover, the binding site of sensors with Al(3+) were determined by (1)HNMR titration experiments.

5.
Talanta ; 273: 125908, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503119

RESUMO

A highly sensitive and selective upconversion near-infrared (NIR) fluorescence and colorimetric dual readout hydrogen sulfide (H2S) nanoprobe was constructed based on the excellent NIR fluorescence emission performance of upconversion nanomaterials (UCNPs), the specific recognition effect of synergistically synthesized gold nanoflowers (trypsin-stabled AuNFs (Try-AuNFs)) and the effective NIR fluorescence quenching capability. In this assay, the sensing strategy included three processes. First of all, the synthesized UCNPs can emit 803 nm NIR fluorescence when they were excited by 980 nm excitation light. Secondly, as a result of the principle of fluorescence resonance energy transfer (FRET), Try-AuNFs can effectively quench the NIR fluorescence of UCNPs at 803 nm, which can effectively improve the signal-to-background ratio of nanoprobes, thereby improving the sensitivity of the probes. Thirdly, in the presence of H2S, the Try protective layer on the surface of Try-AuNFs was specifically penetrated, which will subsequently cleave Try-AuNFs via the strong S-Au bond. As such, the NIR fluorescence of UCNPs will be restored, achieving high selectivity and sensitivity detection of H2S. Under optimized conditions, the linear response range of H2S was 0.1-300 µM, and the detection limit was 53 nM. It is worth noting that the Try on the surface of Try-AuNFs via the synergistic effect can increase the steric hindrance of the probe, and this can effectively prevent the interaction between the probe with biothiols (cysteine (Cys), homocysteine (Hcy)) and other natural amino acids (non-thiol-containing) with resultant in the high selectivity regarding the detection of H2S in human serum, which is unlikely to be achieved by AuNFs synthesized by the gold seed method (Se-AuNFs). This work not only provided a new type of UCNPs fluorescence quencher and recognition unit, but also exemplified that the use of the physical properties (steric hindrance) of protein ligands on the surface of nanoflowers can improve the specificity of the probe. This will provide new ideas for the design of other nanoprobes.


Assuntos
Sulfeto de Hidrogênio , Nanoestruturas , Humanos , Ouro/química , Transferência Ressonante de Energia de Fluorescência/métodos , Cisteína
6.
J Fluoresc ; 23(6): 1239-45, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23828513

RESUMO

In the paper, a novel rhodamine6G based fluorescent chemosensor bearing 3-carbaldehyde chromone was designed and synthesized. According to the fluorescence behavior toward several metal ions, it showed highly selectivity and sensitivity to Zn(II) over other commonly coexistent metal ions (Cu(II), Cd(II), Hg(II), Mg(II), K(I), Pb(II), Fe(III) and Cr(III)) in aqueous environment (pH = 7.4). Meanwhile the binding constant between Zn(II) and chemosensor achieved 6.21 × 10(11) M(-1) in aqueous media. Moreover, according to the Job plot, 1:1 stoichiometry between Zn(II) and sensor was deduced in aqueous media (pH = 7.4). The good selectivity and sensitivity in aqueous media effectively enhanced the application value of the fluorescent chemosensor for Zn(II).


Assuntos
Corantes Fluorescentes/química , Rodaminas/química , Zinco/análise , Corantes Fluorescentes/síntese química , Íons/análise , Modelos Moleculares , Estrutura Molecular , Rodaminas/síntese química , Espectrometria de Fluorescência , Água/química
7.
Chem Commun (Camb) ; 58(62): 8706-8709, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35833515

RESUMO

Stable Fe-based superhydrophobic surfaces are constructed via a hydrothermal method and an autocatalytic CO hydrogenation reaction. The platform molecule of syngas is proposed as an alternative to traditional low-free-energy materials. Syngas may be a powerful tool for fabricating superhydrophobic surfaces that can catalyze the CO hydrogenation reaction.

8.
RSC Adv ; 12(3): 1258-1264, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35425208

RESUMO

As a class of important carbon nanomaterial, carbonized polymer dots (CPDs), also called carbon dots (CDs), have aroused wide interest owing to their unique water solubility, fluorescence properties, and rich surface functional groups. However, the directional tuning of the fluorescence properties of CPDs remains incomplete because of the influence of many factors like diameter, solvent and surface groups. Particularly, most carbonized polymer dots are synthesized in a neutral pH environment. Herein, by modulating the pH (strongly acidic or alkaline) of dextrin water solution, bicolor fluorescence emission (blue and yellow) CPDs were prepared by a hydrothermal reaction. Through systematic characterization, it was found that the different fluorescence properties are regulated by the diameters and surface groups of the carbon cores. Simultaneously, the pH value affected the nucleation process. Based on the excellent fluorescence properties, cell fluorescence imaging and cytotoxicity were tested. The bicolor fluorescence CPDs obtained by tuning the pH provide an important theoretical basis for the design of broadband CPDs.

9.
J Fluoresc ; 21(3): 1091-102, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21161345

RESUMO

A novel Schiff base ligand, chromone-3-carbaldehyde-aminophenazone (L) and its Ln(III) (Ln = La, Yb) complexes were synthesized and characterized by physicochemical methods. The interaction between the ligand, Ln(III) complexes and calf thymus DNA in physiological buffer (pH=7.10) was investigated by using UV-vis spectroscopy, fluorescence spectra, ethidium bromide experiments and viscosity measurements, indicating that the studied compounds can all bind to DNA via an intercalation binding mode and the complexes have stronger binding affinity than the free ligand alone. Furthermore, antioxidant activity of the ligand and its complexes was determined by superoxide and hydroxyl radical scavenging methods in vitro, suggesting that Ln(III) complexes inhibit stronger antioxidant activity than the ligand alone and some standard antioxidants, such as mannitol and vitamin C.


Assuntos
Antioxidantes/química , DNA/química , Elementos da Série dos Lantanídeos/química , Bases de Schiff/química , Aminopirina , Cromonas/química , DNA/metabolismo , Ligantes
10.
Anal Methods ; 13(14): 1681-1686, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33861234

RESUMO

In this paper, a fluorescent compound derived from coumarin and hemicyanine was synthesized and characterized. Herein, we present the fluorescence properties of the probe. Fluorescence selectivity experiments revealed that it exhibited higher ratiometric fluorescence response activity toward NAD(P)H than other commonly coexisting compounds in the cell microenvironment, in accord with the fluorescence shift from red to blue. In addition, the fluorescence identification mechanism was deduced to be a redox reaction between the sensor and NAD(P)H according to the fluorescence behavior. The ratiometric fluorescent probe provided an important theoretical basis for sensing NAD(P)H in vitro and in vivo. We also used this phenomenon to build a sensitive detection platform of NAD(P)H-dependent enzyme activity based on the fluorescence method.


Assuntos
Corantes Fluorescentes , NAD , Carbocianinas , Microambiente Celular , Espectrometria de Fluorescência
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 118964, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32992240

RESUMO

Colorimetric and fluorescent detection of F- have attracted enormous interest owing to their simplicity, low-cost and high selectivity. However, traditional colorimetric and fluorescent sensors mainly based on the insoluble and toxic organic molecules, which is not favorable for sensing F- in water media and living cells. In this work, we designed fluorescent carbon dots (CDs) with excellent water solubility and good biocompatibility as a colorimetric and fluorescent dual-model probe for the detection of F-. The CDs were prepared by a green, one-step hydrothermal strategy from wheat straw without any additives and surface passivation. The obtained CDs exhibited a bright blue fluorescence, special response to F- and low cytotoxicity. More interestingly, a significant color change from light yellow to red can be observed by the naked eye upon addition of F- ions to the CDs solution probably due to the formation of hydrogen bonding between CDs and F-. Besides, the fluorescence of CDs also can be selectively quenched by F- with the detection limit of about 49 µM. Additionally, the CDs are also applied to intracellular imaging and sensing of F- in living cells. This strategy may provide a new method for the detection of F- in water media and biological systems.


Assuntos
Carbono , Pontos Quânticos , Colorimetria , Corantes Fluorescentes , Fluoretos , Pontos Quânticos/toxicidade , Triticum
12.
Bioresour Technol ; 294: 122097, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31539853

RESUMO

The catalytic (SBA-15, Ni/SBA-15, Al/SBA-15 and Ni-Al/SBA-15) hydrothermal liquefaction (HTL) of rice straw biomass was examined at different temperature with different amount of catalyst in the presence of different solvents. In comparison with water solvent liquefaction, the bio-oil yield significantly increased under alcoholic solvent (ethanol and methanol). The highest bio-oil yield was observed for water (44.3 wt%) with Ni-Al/SBA-15, while for ethanol (56.2 wt%), and for methanol (48.1 wt%) with, Ni/SBA-15 catalyst. The loading of Ni and Al on SBA-15, the acid strength of the catalyst enhanced. Bio-oils yield were analyzed with the help of GC-MS, FT-IR, NMR, GPC and CHNS. From the GC-MS analysis, the main monomeric phenolic compounds were produced, phenol, 4-ethyl-phenol, 2-methoxy-phenol, 2-methoxy-4-ethyl-phenol and Vanillin. It was observed by CHNS and GPC analysis of the bio-oil, compared to the non-catalytic liquefaction reaction, the catalytic liquefaction reaction promotes the hydrogenation/hydrodeoxygenation and produced lower molecular weight bio-oils.


Assuntos
Oryza , Fenol , Biocombustíveis , Biomassa , Metais , Fenóis , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Água
13.
RSC Adv ; 9(10): 5377-5383, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35515938

RESUMO

In the study, a highly selective and sensitive fluorescence sensor derived from nitrogen heterocycle was synthesized and characterized. By the fluorescence experiments, it was found to show a higher response toward Al3+ than other commonly coexistent metal ions in C2H5OH/H2O media (pH = 7.2). Moreover, the large binding constant (3.44 × 1014 M-1) between Al3+ and the sensor was calculated by fluorescence titration experiment. In addition, the synergistic effect mechanism due to photoinduced electron transfer (PET) and C[double bond, length as m-dash]N isomerization was deduced according to the fluorescence behavior. In addition, the fluorescence imaging in living cells was studied systemically, which exhibited high fluorescence sensing activity toward Al3+.

14.
Anal Sci ; 33(2): 203-207, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28190841

RESUMO

DNA-templated copper nanoparticles (CuNPs) have recently received considerable interest as functional fluorescent probes for biochemical analysis. In this work, a novel ATP-dependent ligation reactions (ATP-DLR) based ATP assay strategy was proposed by using hairpin-shaped (HS) DNA templated CuNPs as a fluorescent probe. Nick sealing by T4 DNA ligase leads to the formation of intact HS DNA, which can resist the exonuclease cleavage and be taken as the template for CuNPs formation, resulting in strong fluorescence. The proposed ATP detection is label free, sensitive and highly selective, and it has good linearity from 0.02 to 4 µM and a detection limit of 7 nM. This strategy is expected to promote the exploitation and application of DNA-templated CuNPs in biochemical and biomedical studies, and holds great promise in fluorescence detection for other ligation-related biomolecules.


Assuntos
Trifosfato de Adenosina/análise , Técnicas Biossensoriais/métodos , Cobre/química , Sondas de DNA/química , Exonucleases/metabolismo , Sequências Repetidas Invertidas , Nanopartículas Metálicas/química , Trifosfato de Adenosina/química , Sequência de Bases , Sondas de DNA/genética , Sondas de DNA/metabolismo , Espectrometria de Fluorescência
16.
Artigo em Inglês | MEDLINE | ID: mdl-24463240

RESUMO

A new Schiff-base ligand (1) with good fluorescence response to Al(3+), derived from 2-oxo-quinoline-3-carbaldehyde and nicotinic hydrazide, had been synthesized and investigated in this paper. Spectroscopic investigation revealed that the compound 1 exhibited a high selectivity and sensitivity toward Al(III) ions over other commonly coexisting metal ions in ethanol, and the detection limit of Al(3+) ions is at the parts per billion level. The mass spectra and Job's plot confirmed the 1:1 stoichiometry between 1 and Al(3+). Potential utilization of 1 as intracellular sensors of Al(3+) ions in human cancer (HeLa) cells was also examined by confocal fluorescence microscopy.


Assuntos
Alumínio/análise , Hidrazonas/química , Quinolinas/química , Quinolonas/química , Bases de Schiff/química , Ligação Competitiva , Morte Celular , Sobrevivência Celular , Dimetil Sulfóxido/química , Etanol/química , Células HeLa , Humanos , Espaço Intracelular/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Soluções , Espectrometria de Fluorescência
17.
Dalton Trans ; 41(28): 8723-8, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22699422

RESUMO

In the present study, we report new water-soluble cell fluorescence imaging and contrast agents that are based on DTPA-AMC(7-amino-4-methyl coumarin)-Eu(3+) and DTPA-AMC(7-amino-4-methyl coumarin)-Gd(3+) compounds conjugated to Fe(3)O(4) NPs via a PEG-NH(2) linker. The novel Fe(3)O(4) NP-conjugates present two main advantages for cell fluorescence labelling: water solubility and targeting ability. The in vitro experiments demonstrate that water-soluble Fe(3)O(4) NPs-DBI-PEG-NH-DTPA-AMC(7-amino-4-methyl coumarin)-Eu(3+) has excellent cell permeating activity. Moreover, the relaxation rate test of Fe(3)O(4) NPs-DBI-PEG-NH-DTPA-AMC(7-amino-4-methyl coumarin)-Gd(3+) shows a higher T1 relaxation effect than traditional DTPA-Gd(3+) MRI agents. According to in vivo liver MRI experiments, better contrast of the liver was achieved after addition of Fe(3)O(4) NPs-DBI-PEG-NH-DTPA-AMC(7-amino-4-methyl coumarin)-Gd(3+). The results will provide a significant guide for researchers exploring the biomedical applications of superparamagnetic Fe(3)O(4) NPs.


Assuntos
Meios de Contraste/química , Cumarínicos/química , Európio/química , Gadolínio/química , Nanopartículas de Magnetita/química , Ácido Pentético/química , Animais , Meios de Contraste/farmacologia , Cumarínicos/farmacologia , Európio/farmacologia , Gadolínio/farmacologia , Células HeLa , Humanos , Fígado/metabolismo , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/administração & dosagem , Masculino , Camundongos , Microscopia de Fluorescência , Ácido Pentético/farmacologia , Espectrometria de Fluorescência
18.
Dalton Trans ; 40(37): 9370-3, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21847485

RESUMO

In the article, a novel fluorescent probe for the copper cation based on fluorescence quenching mechanism was designed. It exhibited high selectivity for Cu(II) over other common metal ions in aqueous media. Furthermore the coordination between Cu(II) and the organic molecule sensor fabricated an interesting 1D chain coordination polymer framework.

19.
Eur J Med Chem ; 45(11): 5353-61, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20833453

RESUMO

Three novel 2-oxo-quinoline-3-carbaldehyde Schiff-bases and their Cu(II) complexes were synthesized. The molecular structures of Cu(II) complexes were determined by X-ray crystal diffraction. The DNA-binding modes of the complexes were also investigated by UV-vis absorption spectrum, fluorescence spectrum, viscosity measurement and EB-DNA displacement experiment. The experimental evidences indicated that the ligands and Cu(II) complexes could interact with CT-DNA (calf-thymus DNA) through intercalation, respectively. Comparative cytotoxic activities of ligands and Cu(II) complexes were also determined by MTT [3-(4,5-dimethyl-2-thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide] and SRB (sulforhodamine B) methods. The results showed that the three Cu(II) complexes exhibited more effective cytotoxic activity against HL60 cells and HeLa cells than corresponding ligands. Also, CuL(3) showed higher cytotoxic activity than CuL(1) and CuL(2).


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Cobre/química , DNA/química , Quinolinas/química , Quinolinas/farmacologia , Bases de Schiff/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Espectrometria de Fluorescência , Viscosidade
20.
Eur J Med Chem ; 44(11): 4477-84, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19577824

RESUMO

Two novel 2-oxo-quinoline-3-carbaldehyde (4'-hydroxybenzoyl) hydrazone, thiosemicarbazone ligands and its corresponding Cu(2+) complexes were synthesized, and the two complexes' structures were determined by X-ray single crystal diffraction. The interaction of the two Cu(2+) complexes with calf thymus DNA (CT-DNA) was investigated by electronic absorption spectroscopy, fluorescence spectroscopy and viscosity measurement. The experimental evidences indicated that the two water-soluble Cu(2+) complexes could strongly bind to CT-DNA via an intercalation mechanism. The intrinsic binding constants of complexes 1 and 2 with CT-DNA were 7.31 x 10(6) and 2.33 x 10(6)M(-1), respectively. Furthermore, the antioxidant activities (hydroxyl radical and superoxide) of the two water-soluble metal complexes were determined by hydroxyl radical and superoxide scavenging method in vitro.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Cobre/química , DNA/metabolismo , Quinolonas/química , Quinolonas/farmacologia , Animais , Bovinos , Cobre/farmacologia , Cristalografia por Raios X , Fluorescência , Modelos Moleculares , Estrutura Molecular , Bases de Schiff/química , Bases de Schiff/farmacologia , Viscosidade
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