Flexible Luminescent MOF: Trapping of Less Stable Conformation of Rotational Isomers, In Situ Guest-Responsive Turn-Off and Turn-On Luminescence and Mechanistic Study

An efficient, sensitive, and low-cost method has been developed for turn-on fluorescence sensing of dopamine (DA). The method relies on the rapid reaction of DA and 3-Hydroxyphenylboronic acid (3-HPBA) via specific recognition between boronic acids and cis-diol of DA in alkaline solution. The reaction product shows an excitation wavelength of 417 nm and the maximum emission peak at 470 nm. The proposed method allows the determination of DA in the range of 50 nM–25 μM, and the whole detection can be completed within 5 minutes. Furthermore, the presented approach has good selectivity and has been successfully applied to DA sensing in human serum samples, showing great potential in clinical diagnosis.

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Highly selective fluorescence turn-on determination of Pb(II) in Water by in-situ enrichment of Pb(II) and MAPbBr3 perovskite growth in sulfydryl functionalized mesoporous alumina film

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2020.128975 ◽

2021 ◽

Vol 326 ◽

pp. 128975

Author(s):

Shuya Wang ◽

Yipeng Huang ◽

Linchun Zhang ◽

Feiming Li ◽

Fangyuan Lin ◽

...

Keyword(s):

Mesoporous Alumina ◽

Alumina Film ◽

Turn On ◽

Fluorescence Turn On

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Mechanistic study on reduction reaction of nitro compounds catalyzed by gold nanoparticles using in situ SERS monitoring

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2015.01.075 ◽

2015 ◽

Vol 470 ◽

pp. 108-113 ◽

Cited By ~ 18

Author(s):

Qianling Cui ◽

Alexey Yashchenok ◽

Lidong Li ◽

Helmuth Möhwald ◽

Matias Bargheer

Keyword(s):

Gold Nanoparticles ◽

Nitro Compounds ◽

Reduction Reaction ◽

Mechanistic Study

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In-Situ Synthesis and Characterization of Nanocomposites in the Si-Ti-N and Si-Ti-C Systems

Molecules ◽

10.3390/molecules25225236 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5236

Author(s):

Maxime Balestrat ◽

Abhijeet Lale ◽

André Vinícius Andrade Bezerra ◽

Vanessa Proust ◽

Eranezhuth Wasan Awin ◽

...

Keyword(s):

Amorphous Materials ◽

Structural Evolution ◽

Ammonia Nitrogen ◽

Ex Situ ◽

Mechanistic Study ◽

X Ray ◽

Modified Polymer ◽

Amorphous Network ◽

The Matrix

The pyrolysis (1000 °C) of a liquid poly(vinylmethyl-co-methyl)silazane modified by tetrakis(dimethylamido)titanium in flowing ammonia, nitrogen and argon followed by the annealing (1000–1800 °C) of as-pyrolyzed ceramic powders have been investigated in detail. We first provide a comprehensive mechanistic study of the polymer-to-ceramic conversion based on TG experiments coupled with in-situ mass spectrometry and ex-situ solid-state NMR and FTIR spectroscopies of both the chemically modified polymer and the pyrolysis intermediates. The pyrolysis leads to X-ray amorphous materials with chemical bonding and ceramic yields controlled by the nature of the atmosphere. Then, the structural evolution of the amorphous network of ammonia-, nitrogen- and argon-treated ceramics has been studied above 1000 °C under nitrogen and argon by X-ray diffraction and electron microscopy. HRTEM images coupled with XRD confirm the formation of nanocomposites after annealing at 1400 °C. Their unique nanostructural feature appears to be the result of both the molecular origin of the materials and the nature of the atmosphere used during pyrolysis. Samples are composed of an amorphous Si-based ceramic matrix in which TiNxCy nanocrystals (x + y = 1) are homogeneously formed “in situ” in the matrix during the process and evolve toward fully crystallized compounds as TiN/Si3N4, TiNxCy (x + y = 1)/SiC and TiC/SiC nanocomposites after annealing to 1800 °C as a function of the atmosphere.

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