ACS Applied Materials & Interfaces
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2017
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IF 7.504
Lei Zheng,Haili Yu,Yaling Yue,Fengjuan Wu,Yi He
We report a visual chronometric assay for Cr3+ based on the Cu2O nanocube-mediated clock reaction of methylene blue (MB) and N2H4. MB with a blue color can be easily reduced by excess N2H4 to form colorless leuco-MB in the presence of Cu2O nanocubes as a catalyst in a short time. However, the addition of Cr3+ decreases the catalytic activity of Cu2O nanocubes owing to the coordination interactions between them, leading to an increase in the reaction time. The reaction time change was employed for selective detection of Cr3+. This assay has a wide dynamic range from 0.03 to 600 μM with a limit of detection of 2.7 nM. Remarkably, different concentrations of Cr3+ can be directly detected with the naked eye by observing the color-fading speed. Additionally, this assay was successfully used to determine Cr3+ in real water samples.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2023
·Vol. 29
·期 57
·e202301968
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IF 4.3
Zhuo Zhang,Ting Liu,Yawen Li,Yang Yu,Lin Ning,Xuefan Qiu,Chencan Li,Ling Wang,Wenlong Xu
Graphical We demonstrate the temporal programming of the assembly and disassembly of EuW 10 nanospheres using a pH clock reaction of acid/urease hydrolysis. The pH-responsive C 12 DMAO endow EuW 10 nanospheres with dynamical properties, in which fluorescence changes are coded in this system. These fluorescent nanospheres provide new application in time-programmed information encryption. Self-assembly exploits noncovalent interaction to offer an effective method for the fabrication of materials. For Na 9 [EuW 10 O 36 ] ⋅ 32H 2 O (EuW 10 ), the negative charges and abundant oxygen atoms on its surface provide a handle for static self-assembly. New properties are envisioned for EuW 10 aggregates which are able to display such kinetics and time-programming characteristics, in order to satisfy more complex and intelligent application scenarios, such as DNA binding and information encryption. In this work, EuW 10 coupling with stimuli-responsive dodecyl dimethylamine oxide (C 12 DMAO) can generate versatile aggregates with pH-responsive properties. We demonstrated the temporal programming of the assembly and disassembly of EuW 10 nanospheres using a pH clock reaction of acid/urease hydrolysis. The pH clock reaction endows EuW 10 assemblies with dynamical properties, in which the charges and fluorescence changes are coded in this system. These fluorescent assemblies provide new application in time-programmed DNA capture and information encryption.
研究领域:
材料科学
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纳米技术
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生物技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL EDUCATION
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2024
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IF 2.5
Yi Wang,Cuiyan Wu,Jie Chen,Zhiyou Miao,Qiang Wang,Lijuan Luo,Zhongyong Zhang,Minjie Hu,Zhijian Jia
Although chemical kinetics is an essential branch of physical chemistry, observing kinetic processes typically demands sophisticated and costly equipment. Digital green chemistry experiments are an important experimental-teaching direction for undergraduates. This study introduces a portable, interactive, and educational microarray chip platform that visualizes chemical kinetics through clock reactions via dynamic mixing. The microfluidic chip consists of a 3D-printed substrate, modeled in Cinema 4D, and an acrylic glass cover. By precisely controlling variables such as the reactant concentration and temperature with digital coding, we successfully demonstrate two iodine clock reactions, KIO3-KI-H+ and Na2S2O3-I2-(NH4)2S2O8, as well as anthocyanin discoloration. This platform enables the clear visualization of phenomena including radial diffusion and microscale interfacial reactions, presenting the reaction progress in a color-card format referred to as “chemical amber,” which enhances the understanding of abstract chemical concepts. Notably, the chip allows users to calculate key kinetic parameters, including reaction rates, activation energy, and analyte concentration, by measuring diffusion rates, color-change times, and grayscale values from digitally scanned images obtained using a low-cost mini USB-electronic microscope and smartphone. This provides an enriched understanding of reaction dynamics. Furthermore, the platform was successfully implemented in comprehensive experimental teaching applications, demonstrating notable effectiveness in classroom settings.
研究领域:
物理化学
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数字绿色化学
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实验教学
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产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2025
·
IF 4.1
Xiaofeng Wang,Xiao Liu,Lixue Wu,Gang Hu,Zhaohui Fang
Chiral enantiomers of drugs often exhibit distinct pharmacological activities despite their similar physical and chemical properties. Developing efficient methods for their distinguishment is crucial for pharmaceutical quality control. Here, we presented a novel approach using a CTT (Chlorite-Tetramethylammonium Hydroxide-Tetrathionate) clock reaction system for kinetic chiral enantiomer recognition. DOPA enantiomers were selected for this purpose, in which L-DOPA is therapeutic efficacy in treating Parkinson's disease by precursoring dopamine while D-DOPA lacks such a function. By introducing equal amounts of L-DOPA and D-DOPA into the CTT clock system, we observed a more prolonged induction period for L-DOPA compared to D-DOPA, enabling their quick differentiation. Moreover, a linear relationship between the induction period and the concentration (1.190 × 10 −6 mol/L to 4.5238 × 10 −6 mol/L) of L-DOPA or D-DOPA allowed quantitative detection of L-DOPA or D-DOPA samples. This method could also be applied to analyze varying concentration ratios of L-DOPA and D-DOPA mixtures at a fixed total concentration. Study on mechanism indicates that both L-DOPA and D-DOPA react with ClO 2 · radical to finally generate DHICA through oxidation, with their kinetic disparities evident during this process. These kinetic disparities between L-DOPA and D-DOPA oxidation arises from stereospecific hydrogen-bonding interactions in the cyclodopa intermediate. The weaker hydrogen bond in L-DOPA-derived cyclodopa likely facilitates its cleavage during oxidation, thereby accounting for the faster reaction kinetics observed in the clock system compared to D-DOPA. This makes L-DOPA exhibit more fast consumption of chlorine dioxide than D-DOPA, and resulting larger the extension in the induction period with L-DOPA than that with D-DOPA. Such a method coupling CCT clock demonstrates its versatility and potential for broader applications in chiral drug analysis.
研究领域:
分析化学
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手性药物分析
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药学
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化学动力学
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY A
·
2019
·
IF 2.641
György Csekö,Qingyu Gao,Changwei Pan,Li Xu,Attila K. Horváth
The thiourea dioxide–periodate reaction has been investigated under acidic conditions using phosphate buffer within the pH range of 1.1–2.0 at 1.0 M ionic strength adjusted by sodium perchlorate. Absorbance–time series are monitored as a function of time at 468 nm, the isosbestic point of the I2–I3– system. The profile of these kinetic runs follows either sigmoidal-shaped or rise-and-fall traces depending on the initial concentration ratio of the reactants. The clock species iodine appears after a well-defined but reproducible time lag even in substrate excess, meaning that the system may be classified as an autocatalysis-driven clock reaction. It is also demonstrated that the age of the thiourea dioxide solution markedly shortens the Landolt time, suggesting that the original form of thiourea dioxide (TDO) rearranges into a more reactive form and reacts faster than the original one. The behavior found is consistent with that recently observed in other oxidation reactions of TDO. To characterize the system quantitatively, a 22-step kinetic model is constructed from adapting the kinetic model of the TDO–iodate reaction published recently by supplementing it with six different reactions of periodate. By the help of seven fitted rate coefficients a sound agreement between the measured and calculated absorbance–time traces is obtained.
研究领域:
物理化学
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反应动力学
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无机化学
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分析化学
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化学动力学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）