- Generation of Reactive Oxygen Species via Electroprotic Interaction of H2O2 with ZrO2 Gel: Ionic Sponge Effect and pH-Switchable Peroxidase- and Catalase-Like Activity
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Formation of reactive oxygen species (ROS) is of vital importance in catalytic oxidation chemistry. In this paper we have shown that a nonredox system such as amorphous zirconium dioxide (a-ZrO2) is highly active in ROS formation via H2O2 decomposition. Interaction between a-ZrO2 and H2O2 in aqueous solution was investigated by means of EPR, HYSCORE, Raman, and UV-vis, along with auxiliary FTIR, TG-MS, and XPS techniques, in a broad range of pH values and H2O2 concentrations. Various reaction intermediates such as superoxide (O2?-) and hydroxyl (?OH) radicals as well as peroxide (O22-) species were identified. At pH 2 gel exhibited peroxidase-type activity, quantified by an o-phenylenediamine assay. At pH >5.3 formation of O22- is accompanied by a substantial release of O2 due to the pronounced catalase-like activity of a-ZrO2. The role of electroprotic processes (an interfacial proton transfer coupled with an intermolecular electron transfer) in H2O2 decomposition and ROS formation was elucidated, and a plausible mechanism of this reaction, ≡Zr+-HO2-(surf) + H2O2(aq) → ?OH(aq) + ≡Zr+-O2?-(surf) + H2O, was proposed. The surface of a-ZrO2 covered with hydroxyl groups plays a role of an ionic sponge, which controls the electroprotic equilibrium by capturing the charged reaction intermediates. Unlike the amorphous gel, crystalline zirconia exhibits only weak activity in the production of the O2?- and ?OH radicals, and a different mechanism is involved. It is worth mentioning that the activity of the zirconia gel catalyst in ROS generation, as gauged by the Michaelis-Menten constant, is comparable (ca. 40%) to that of the Fenton-type oxides (Fe3O4, Co3O4).
- Sobańska, Kamila,Pietrzyk, Piotr,Sojka, Zbigniew
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- Highly sensitive SERS sensor for mercury ions based on the catalytic reaction of mercury ion decorated Ag nanoparticles
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A surface-enhanced Raman scattering (SERS) sensor of mercury ions based on the coordinated catalytic reaction of Hg2+-Ag nanoparticles (NPs) has been designed and constructed for water quality monitoring. We combined Ag NPs (average particle size is 49 nm) with mercury ions to form Hg2+-Ag NPs in aqueous phase by electrostatic interactions. The formed Hg2+-Ag particles can catalyze a redox reaction between o-phenylendiamine (OPD) and dissolved oxygen to form 2,3-diaminephenazine (DAP), which is Raman-active and possesses a strong SERS signal due to the adherence to Ag NPs. Therefore we can trace the SERS intensity of DAP to determine mercury ions and the lowest detectable concentration of mercury is 1.0 nM using this method. This sensor displays higher sensitivity and selectivity and it possesses a certain value in terms of water quality detection.
- Qi, Guohua,Fu, Cuicui,Chen, Gang,Xu, Shuping,Xu, Weiqing
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- Facile synthesis of a Fe3O4/MIL-101(Fe) composite with enhanced catalytic performance
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A magnetic porous material, Fe3O4/MIL-101(Fe), has been successfully fabricated by using simple ultrasound-assisted electrostatic self-assembly technology, and was demonstrated to be a highly active heterogeneous catalyst for the dimerization reaction of o-phenylenediamine (OPD) in the presence of H2O2via synergistic peroxidase-like activity.
- Jiang, Zhong Wei,Dai, Fu Qiang,Huang, Cheng Zhi,Li, Yuan Fang
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- Thermal responsive microgels as recyclable carriers to immobilize active proteins with enhanced nonaqueous biocatalytic performance
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We describe the preparation of a thermoresponsive microgel, which can non-covalently immobilize active proteins with enhanced biocatalytic performance in organic solvents and easy reusability due to the porous microstructure and temperature responsive property.
- Wu, Qing,Su, Teng,Mao, Yanjie,Wang, Qigang
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- A nano-sized Cu-MOF with high peroxidase-like activity and its potential application in colorimetric detection of H2O2and glucose
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Peroxidase widely exists in nature and can be applied for the diagnosis and detection of H2O2, glucose, ascorbic acid and other aspects. However, the natural peroxidase has low stability and its catalytic efficiency is easily affected by external conditions. In this work, a copper-based metal-organic framework (Cu-MOF) was prepared by hydrothermal method, and characterized by means of XRD, SEM, FT-IR and EDS. The synthesized Cu-MOF material showed high peroxidase-like activity and could be utilized to catalyze the oxidation ofo-phenylenediamine (OPDA) and 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2. The steady-state kinetics experiments of the oxidation of OPDA and TMB catalyzed by Cu-MOF were performed, and the kinetic parameters were obtained by linear least-squares fitting to Lineweaver-Burk plot. The results indicated that the affinity of Cu-MOF towards TMB and OPDA was close to that of the natural horseradish peroxidase (HRP). The as-prepared Cu-MOF can be applied for colorimetric detection of H2O2and glucose with wide linear ranges of 5 to 300 μM and 50 to 500 μM for H2O2and glucose, respectively. Furthermore, the specificity of detection of glucose was compared with other sugar species interference such as sucrose, lactose and maltose. In addition, the detection of ascorbic acid and sodium thiosulfate was also performed upon the inhibition of TMB oxidation. Based on the high catalytic activity, affinity and wide linear range, the as-prepared Cu-MOF may be used for artificial enzyme mimics in the fields of catalysis, biosensors, medicines and food industry.
- Ren, Chunguang,Tian, Xuemei,Wang, Zhonghua,Wu, Hanliu,Yu, Hao,Zhou, Yafen
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- A Phenazine based colorimetric and fluorescent chemosensor for sequential detection of Ag+ and I? in aqueous media
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A new colorimetric and fluorescent probe MNTPZ based on 1H-imidazo[4,5-b]phenazine derivative has been designed and synthesized for successive detection of Ag+ and I?. The probe MNTPZ shows selective colorimetric response by a change in color from yellow to orange and “turn-off” fluorometric response upon binding with Ag+ in DMSO: Water (pH = 7, 1:1, v/v) over other cations. The binding mode of probe MNTPZ to Ag+ was studied by Job's plot, 1H NMR studies, FT-IR spectroscopy and DFT calculations. Moreover, the situ generated probe MNTPZ+ Ag+ complex acted as an efficient fluorometric “turn-on” probe for I? via Ag+ displacement approach. The detection limit of probe MNTPZ for Ag+ and the resultant complex probe MNTPZ+ Ag+ for I? were determined to be 1.36 μmol/L and 1.03 μmol/L respectively. Notably, the developed probe was successfully used for quantitative determination of I? in real samples with satisfactory results.
- Dongare, Pravin R.,Gore, Anil H.,Kolekar, Govind B.,Ajalkar, Balu D.
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- Phenazine-2,3-diamine
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The structure of the 2,3-diamino phenazine (DAP) in its non-protonated form was described. The crystal packing, which features π-π, hydrogen- and T-bonded interactions, was analyzed. The chemistry of the DAP was demonstrated using organic transformations. The characterization of the compound was done by nuclear magnetic resonance (NMR), absorption and emission techniques.
- Doyle, Robert P.,Kruger, Paul E.,Mackie, Philip R.,Nieuwenhuyzen, Mark
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- Au-Ag and Pt-Ag bimetallic nanoparticles@halloysite nanotubes: Morphological modulation, improvement of thermal stability and catalytic performance
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In this study, Au-Ag and Pt-Ag bimetallic nanocages were loaded on natural halloysite nanotubes (HNTs) via galvanic exchange based on Ag@HNT. By changing the ratio of Au to Ag or Pt to Ag in exchange processes, Au-Ag@HNT and Pt-Ag@HNT with different nanostructures were generated. Both Au-Ag@HNT and Pt-Ag@HNT systems showed significantly improved efficiency as peroxidase-like catalysts in the oxidation of o-phenylenediamine compared with monometallic Au@HNT and Pt@HNT, although inert Ag is dominant in the composition of both Au-Ag and Pt-Ag nanocages. On the other hand, loading on HNTs enhanced the thermal stability for every system, whether monometallic Ag nanoparticles, bimetallic Au-Ag or Pt-Ag nanocages. Ag@HNT sustained thermal treatment at 400 °C in nitrogen with improved catalytic performance, while Au-Ag@HNT and Pt-Ag@HNT maintained or even had slightly enhanced catalytic efficiency after thermal treatment at 200 °C in nitrogen. This study demonstrated that natural halloysite nanotubes are a good support for various metallic nanoparticles, improving their catalytic efficiency and thermal stability.
- Li, Siyu,Tang, Feng,Wang, Huixin,Feng, Junran,Jin, Zhaoxia
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- Fluorescent and Colorimetric Dual-Readout Assay for Inorganic Pyrophosphatase with Cu2+-Triggered Oxidation of o-Phenylenediamine
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We demonstrate a rationally designed fluorescent and colorimetric dual-readout strategy for the highly sensitive, quantitative determination of inorganic pyrophosphatase (PPase) activity, a key hydrolytic enzyme involved in a variety of metabolic processes. Inspired by the selective oxidative and chromogenic reaction of o-phenylenediamine (OPD) with Cu2+, the special inhibitory effects of pyrophosphate (PPi) on the oxidative ability of Cu2+, and the specific hydrolysis of PPi into orthophosphate by PPase, a convenient small molecule OPD-based analytical system was developed for Cu2+/PPi recognition and PPase activity assay. We have confirmed that Cu2+ acts as the oxidant in the reaction and the main chromogenic product of OPD is 2,3-diaminophenazine (usually called OPDox) in the assay by combining the ESI-MS, 1H NMR, and XPS spectra analysis. Direct electrochemical insights into the Cu2+-triggered and PPi-inhibited mechanism were performed by cyclic voltammetry characterizations of the Cu2+ in the absence and presence of PPi for the first time. Furthermore, the proposed analytical system with clear response mechanism exhibits a promising outlook for the PPase activity assay in real biological samples and inhibitor screening.
- Sun, Jian,Wang, Bin,Zhao, Xue,Li, Zong-Jun,Yang, Xiurong
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- Cu MOF-based catalytic sensing for formaldehyde
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Developing a catalyst with a uniform and well-defined crystal structure is very important to establish a catalytic sensing system with high efficiency. In this work, Cu-BTC metal-organic frameworks (MOFs) without a crystalline CuO or Cu2O phase were successfully synthesized by using a low temperature synthesis method, and the as-prepared Cu-BTC MOFs were found to have outstanding catalytic activity towards the traditional oxidase substrate, o-phenylenediamine (OPD), to generate a colored and fluorescent product. The results of the kinetics analysis revealed that the catalytic behavior of Cu-BTC MOFs towards OPD could well follow the typical Michaelis-Menten equation, indicative of a strong affinity between Cu-BTC MOFs and OPD. On the basis of these findings, taken together the condensation reaction between the -CHO group of formaldehyde and the -NH2 group of OPD to form Schiff base compounds, a novel Cu-BTC MOF-based catalytic sensing system for detecting gaseous formaldehyde could be successfully established.
- Gao, Ping,Sun, Xiang-Ying,Liu, Bin,Lian, Hui-Ting,Liu, Xin-Qiang,Shen, Jiang-Shan
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- Highly selective and sensitive recognition of histidine based on the oxidase-like activity of Cu2+ ions
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Developing simple, highly sensitive and selective sensing systems for histidine (His) is important due to its biological significance. In this report, Cu2+ ions serving as the oxidase mimics towards O-phenylenediamine (OPD) were investigated in detail. Experimental results revealed that the oxidase-like activity of Cu2+ ions is substantially higher than that of Cu/CuO nanoparticles. On the basis of these findings, a simple, highly sensitive and selective PL sensing platform for His could be developed, with a limit of detection (LOD) as low as 0.33 μM. Furthermore, experiments of His recovery in human urine samples were successfully conducted by employing the established sensing system with satisfactory results.
- Xu, Yan,Wu, Xiao-Qiong,Shen, Jiang-Shan,Zhang, Hong-Wu
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- Iron(III) complexes of bis (benzimidazol-2-yl) methyl) thiophene-2,5- dicarboxamide: Synthesis, spectral and oxidation of o-phenylenediamine
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Iron(III) complexes of a potentially pentadentate ligand N2, N5-bis ((1H-benzo [d] imidazol-2-yl) methyl) thiophene-2,5- dicarboxamide are synthesized with an exogenous anion X = Cl-, NO3-. M?ssbauer and EPR spectroscopy indicates axially distorted complexes. These complexes were utilized for the oxidation of o-phenylenediamine to 2,3-diaminophenazine in presence of H2O2. The initial rate of reaction is dependent on the concentration of o-phenylenediamine as well as the iron(III) complex. Rates of reaction were found to be at least five times higher for the Cl- bound complex. The effect of an added anion like acetate, azide and citrate is found to inhibit the rate of reaction. This suggests that one of the factors affecting the rate determining step is the binding of these anions on a vacant site at the iron(III) centre. The oxidation of o-phenylenediamine to 2,3-diaminophenazine is reminiscent of the functioning of horse radish peroxidase.
- Tyagi, Nidhi,Mathur, Pavan
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- A novel self-assembled supramolecular sensor based on thiophene-functionalized imidazophenazine for dual-channel detection of Ag+ in an aqueous solution
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Herein, a novel self-assembled supramolecular sensor (S1) based on thiophene-functionalized imidazophenazine for Ag+ was designed and synthesized. It showed dual-channel detection properties for Ag+ based on the competitive mechanism of supramolecular self-assembly with high sensitivity and selectivity even in the presence of other metal ions. Its detection limit for Ag+ is 8.18 × 10-9 M. Upon the addition of Ag+, the solution changes from yellow to light purple and the fluorescence is quenched. Furthermore, the sensing mechanism between Ag+ and S1 is investigated via IR and 1H NMR spectroscopy, mass spectrometry, and density functional theory calculations.
- Shi, Hai-Xiong,Li, Wen-Ting,Li, Qiao,Zhang, Hai-Li,Zhang, You-Ming,Wei, Tai-Bao,Lin, Qi,Yao, Hong
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- Photoinduced DNA cleavage and cellular damage in human dermal fibroblasts by 2,3-diaminophenazine
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Aromatic amines, such as o-phenylenediamine (OPD), have been used extensively in commercial hair dyes and in the synthesis of agricultural pesticides. Air oxidation of OPD resells in the formation of 2,3-diaminophenazine (DAP). Although the mutagenic toxicity of DAP has been shown in both prokaryotic and eukaryotic systems, its phototoxicity remains largely unexplored. This study focuses on the pH-dependent photophysical properties of DAP and demonstrates its ability to photoinduce DNA damage to pUC19 plasmid in vitro. The photocytotoxicity of DAP toward human skin fibroblasts was also measured. DAP exhibits weak intercalative binding to double-stranded DNA with a binding constant Kb = 3.5 × 10 3 M-1. Furthermore, upon irradiation with visible light, DAP is able to nick plasmid DNA in the presence of oxygen. The concentration of DAP that resulted in 50% cell death was 172 ± 9 μM in the dark and 13 ± 1 μM after irradiation of the DAP-treated cell cultures with visible light (400-700 nm, 30 min, 5 J/ cm2). The 13-fold increase in toxicity upon exposure to visible light shows the need for further study of the photocytotoxicity of contaminants such as DAP.
- Fu, Patty K.-L.,Abuzakhm, Sonia,Turro, Claudia
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- High stability in organic solvent of heme proteins immobilized in the interlayers of magadiite nanoparticles
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Enzymatic activities of heme proteins, myoglobin (Mb) and hemoglobin (Hb), immobilized in the interlayers of magadiite nanoparticles under mild condition, toward the oxidation of o-phenylenediamine (OPD) in an organic solvent were firstly reported. The immobilized heme proteins showed higher stability than that of free Mb and Hb in organic toluene solution.
- Peng, Shuge,Gao, Qiuming,Shi, Jianlin
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- Unique dual responsive activity of a platinum nanozyme stabilized by a green solvent: Deep eutectic solvents
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Cubical Pt nanozymes with a size distribution of 6-8 nm synthesized in and stabilized by eco-friendly choline chloride/glycerol deep eutectic solvent displayed outstanding catalytic performance in the oxidation of uric acid with an activation energy of 37.473 kJ mol-1 and decomposition of en route generated H2O2. Significantly, the exploited one pot nanozyme cascade reaction has proven the novel uricase and peroxidase dual responsive enzyme mimetic activity of the ensuing Pt nanocubes unravelling future prime applications.
- Devi, Henam Sylvia,Singh, Henam Premananda
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- Colorimetric and fluorescent dual-mode strategy for sensitive detection of sulfide: Target-induced horseradish peroxidase deactivation
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Environmental pollution caused by sulfide compounds has become a major problem for public health. Hence, accurate detection of sulfide anions (S2?) level is valuable and vital for environmental monitoring and protection. Here, we report a new colorimetric/fluorescent dual-mode sensor for the determination of S2? based on the inhibition of enzyme activity and the unique optical properties of produced 2,3-diaminophenazine (DAP), thus making the analytical results more convincing. In this strategy, horseradish peroxidase (HRP) enzyme is used for catalyzing the H2O2-mediated oxidation of o-phenylenediamine (OPD) to produce DAP, and the color changed to bright yellow and produced orange yellow fluorescence. But the presence of S2? could cause the deactivation of HRP, which decreased the amount of DAP and consequently resulted in a substantial SPR band fading and an evident fluorescence quenching simultaneously. The mechanism of S2? sensor was examined by combining the UV–vis absorption spectra, fluorescence spectra and electrospray ionization mass spectrometry analysis. Under optimal conditions, the colorimetric and fluorescent linear responses of the proposed method exhibited a wide linear range from 2.5 nM–7.5 μM with ultralow detection limits of 1.2 nM and 0.9 nM, respectively. Some potential interferents (such as F?, Cl?, Br?, I?, SO4 2?, SO3 2?, SCN?, H2PO4 ?, HPO4 2?, Ac?, NO3 ?, CO3 2?) in real samples showed no interference. Moreover, the proposed method offered advantages of simple, low-cost instruments and rapid assay without the utilization of nanomaterials and has been successfully applied to determine S2? content in lake water samples with satisfying recoveries over 97.6%. More importantly, the present S2? sensor not only afforded a new optical sensing pattern for bioanalysis and environment monitoring, but also extends the application field of HRP-catalyzed OPD–H2O2 system.
- Bao, Jie,Lu, Haifeng,Peng, Guoyu,Xu, Shuxin,Zhao, Lihua
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- Cascade Chromogenic System with Exponential Signal Amplification for Visual Colorimetric Detection of Acetone
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The signal of the traditional chromogenic systems is directly proportional to analyte concentration, leading to an unsatisfactory sensitivity. Herein, we report a cascade chromogenic system to realize exponential amplification of colorimetric signal through coupling chemical oxidation with photoinduced radical chain reaction. The chemical oxidation of o-phenylenediamine (OPD) by Fe3+ generates Fe2+ and photoactive 2,3-diaminophenazine (DAP). Under blue-light irradiation, DAP initiates the formation of holes and H2O2 that reacts with Fe2+ to hydroxyl radicals (·OH) and Fe3+ via an intersystem crossing (ISC) process. Moreover, the holes oxidize water to yield ·OH as well. The resulting ·OH and regenerated Fe3+ in turn oxidize OPD to yield more DAP, leading to a self-propagating reaction cycle that continues to proceed until all the OPD molecules are consumed, along with a distinct color change from colorless to yellow. Through the generation of the complex between DAP and acetone that limits the ISC process, and therefore quenches the colorimetric signal, the highly sensitive and selective naked-eye detection of acetone is achieved from 50 μM to 3 mM, with a limit of detection of 35 μM. Additionally, the feasibility of this colorimetric assay to detect acetone in real water samples is also demonstrated.
- He, Yi,Li, Hua,Liang, Jingkai,Wang, Junren,Yu, Haili
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- Oxidation of o-phenylenediamine to 2,3-diaminophenazine in the presence of cubic ferrites MFe2O4 (M = Mn, Co, Ni, Zn) and the application in colorimetric detection of H2O2
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Metal ferrites nanocrystallites, MFe2O4 (M?=?Mn, Co, Ni, Zn) were prepared by coprecipitation method and characterized by a combination of physico-chemical and spectroscopic techniques. MFe2O4 nanoparticles having particle size in the range 10–35?nm were tested as catalysts in the oxidation of o-phenylenediamine (OPD) to 2,3–diaminophenazine (DAP) using hydrogen peroxide as oxidant at room temperature. Kinetic data was collected for the catalytic oxidation of OPD to DAP by monitoring the UV–vis absorbance at 415?nm and fit well to the Michaelis–Menten model yielding kinetic parameters Km (Michaelis–Menten constant) and Vmax (maximum rate of reaction). MnFe2O4 nanoparticles provide the highest catalytic activity in the oxidation of OPD to DAP at room temperature. A colorimetric method was developed based on the MnFe2O4/OPD system for the detection of H2O2 in reaction solution. The method has a detection limit of 30 μM for H2O2 and wide linear range.
- Vetr, Fahime,Moradi-Shoeili, Zeinab,?zkar, Saim
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- Simple and label-free fluorescence detection of ascorbic acid in rat brain microdialysates in the presence of catecholamines
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Ascorbic acid (AA), as one of the most important neurochemicals in cerebral systems, plays a vital role in many physiological and pathological processes. Herein, a facile, label-free, and ultrasensitive fluorescence sensing system was developed for the determination of AA based on the Ag+-o-phenylenediamine (OPD) interaction. OPD could be oxidized by Ag+ to generate fluorescent 2,3-diaminophenazine (OPDox). When AA was introduced, on the one hand, AA can inhibit the oxidation process due to its strong reducing capability. On the other hand, AA can be oxidized to dehydro-AA with an absorption peak at 380 nm, which has a good spectral overlap with the emission of OPDox. Thus, the inner filter effect (IFE) between dehydro-AA and OPDox may occur. Therefore, the introduction of AA can intensively suppress the fluorescence of the Ag+-OPD system. Benefitting from the remarkable synergistic effect of the reducing capability of AA and IFE, a facile and ultrasensitive sensor was constructed successfully for AA sensing. The whole detection procedure was achieved within 10 min. The linear response range of AA was obtained from 0.05 to 40 μM with a detection limit of 10 nM. This developed method has many merits including more simplicity, good selectivity, excellent biocompatibility, and more cost-effectiveness without using any nanomaterials. Notably, the proposed method was successfully applied to detect AA in rat brain microdialysates in the presence of catecholamines, thus providing a new route for AA detection in physiological and pathological fields.
- Zhu, Shuyun,Lei, Cuihua,Gao, Yue,Sun, Jing,Peng, Hongwei,Gao, Han,Zhang, Ruixue,Wang, Rui,Zhao, Xian-En,Wang, Hua
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- o-Phenylenediamine as a reaction-based probe for the fluorescent detection of Ce(IV) ions
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o-Phenylenediamine as a new fluorescent probe is designed for detecting Ce(IV) ions. The mechanism of detection relies on the oxidative activity of Ce(IV) ions, which can promote the oxidative cyclization of o-Phenylenediamine leading to the formation of fluorescent 2,3-diaminophenazine and giving a more than 150-fold fluorescence enhancement. Furthermore, the o-Phenylenediamine fluorescent probe was effectively used for the detection of Ce(IV) ions in river water, tap water, rainwater, and lateritic soil from Ganzhou.
- Lai, Xiaojing,Ye, Qiuxiang,Wang, Ruixiang,Wang, Peng,Liu, Jin-Biao
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- A two fluorescent signal indicator-based ratio fluorometric alkaline phosphatase assay based on one signal precursor
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Two fluorescent signal indicators were simply converted from one organic precursor system by using the superior oxidation capability of manganese dioxide (MnO2) nanosheets for the first time, finally resulting in the successful fabrication of a ratio fluorometric bioassay of alkaline phosphatase (ALP).
- Wang, Rongji,Wang, Zhihua,Rao, Honghong,Xue, Xin,Luo, Mingyue,Xue, Zhonghua,Lu, Xiaoquan
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- Ratiometric fluorescent sensor based oxazolo-phenazine derivatives for detect hypochlorite via oxidation reaction and its application in environmental samples
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In this work, we designed and synthesized a ratiometric fluorescent sensor (POC) based phenazine derivative which can specifically detect hypochlorite (detection limit equals to 8.9 × 10?7 M) in DMSO/H2O (3:7, v/v) solution. With addition of hypochlorite to the solution of POC, hypochlorite broken π-π stacking of POC, and then oxidizes sulfur atoms in phenazine groups to sulfoxide, which resulted in the fluorescent color changed from blue to yellow. Job's plot showed that binding stoichiometry of POC with ClO? was 2:1. In addition, POC could be used to real-time detect hypochlorite in environment samples, and the naked eyes detection limit reached up to 7 × 10?5 M.
- Zhang, You-Ming,Fang, Hu,Zhu, Wei,He, Jun-Xia,Yao, Hong,Wei, Tai-Bao,Lin, Qi,Qu, Wen-Juan
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- Determination of myoglobin based on its enzymatic activity by stopped-flow spectrophotometry
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A new method has been developed for the determination of myoglobin (Mb) based on its enzymatic activity for the oxidation of o-phenylenediamine (OPDA) with hydrogen peroxide. Stopped-flow spectrophotometry was used to study the kinetic behavior of the oxidation reaction. The catalytic activity of Mb was compared to other three kinds of catalyst. The time dependent absorbance of the reaction product, 2,3-diamimophenazine (DAPN), at a wavelength of 426 nm was recorded. The initial reaction rate obtained at 40 °C was found to be proportional to the concentration of Mb in the range of 1.0 × 10 -6 to 4.0 × 10-9 mol L-1. The detection limit of Mb was found to be 9.93 × 10-10 mol L-1. The relative standard deviations were within 5% for the determination of different concentrations of Mb. Excess of bovine serum albumin (BSA), Ca(II), Mg(II), Cu(II), glucose, caffeine, lactose and uric acid did not interfere.
- Zheng, Qi,Liu, Zhihong,Cai, Ruxiu
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- A ratiometric fluorescence probe based on carbon dots for discriminative and highly sensitive detection of acetylcholinesterase and butyrylcholinesterase in human whole blood
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A ratiometric fluorescence probe based on carbon dots (CDs) was developed for discriminative and highly sensitive detection of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity in human whole blood. When o-phenylenediamine (OPD) was oxidized by Cu2+, the product 2,3-diaminophenazine (oxOPD) could effectively quench the fluorescence of CDs at 460 nm due to the inner filter effect and gave rise to a new emission peak at 570 nm. The AChE or BChE catalyzed hydrolysis reaction of acetylthiocholine or butyrylthiocholine to generate thiocholine, whose sulfhydryl group strongly captured Cu2+ to inhibit the oxidization of OPD, thus effectively preserving the natural fluorescence emission of CDs. The resulting fluorescence intensity ratio served as the signal output of the probe for cholinesterases (ChEs) activity sensing. The activities of AChE and BChE were determined to range from 0.2 to 14.0 U L?1 and from 0.1 to 5.0 U L?1, with detection limits of 0.1 U L?1 and 0.04 U L?1, respectively. Additionally, the IC50 of tacrine and ethopropazine for the inhibition of AChE and BChE were estimated to be 29.8 nM and 132.6 nM, respectively. Moreover, the probe was successfully applied to the discriminative determination of AChE and BChE in human whole blood without any pretreatment. These results suggested that the proposed strategy provided a discriminative, sensitive and robust analytical platform for ChEs clinical diagnostics and drug screening.
- Xu, Xiaoman,Cen, Yao,Xu, Guanhong,Wei, Fangdi,Shi, Menglan,Hu, Qin
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- Observation of intermediates by online mass spectrometry to demonstrate the multiple mechanisms of dye-sensitized photocatalysis
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Online mass spectrometry was applied to reveal multiple mechanisms of visible-light irradiated dye-sensitized photocatalysis foro-phenylenediamine oxidation. The reactants, products and short-lived intermediates were recorded and dynamically tracked. Dimer and unexpected trimer intermediates were observed to deduce the stepwise aerobic photooxidation mechanism with multiple routes, which was supported by theoretical calculations.
- Sun, Jianghui,Fan, Xuchan,Lu, Hua,Tan, Hongwei,Zhang, Ying,Wang, Yan,Zhao, Yunling,Ouyang, Jin,Na, Na
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- A green approach to the synthesis of 2,3-diaminophenazine using a photocatalytic system of CdFe2O4/TiO2 nanoparticles
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In recent years, the development of novel green chemistry routes for the synthesis of organic compounds has become very attractive to many research groups. Nanoparticles have been widely used because of their potential applications in catalysis, environmental remediation, electronic fields, biomedical, and industrial fields. In this article, a rapid, efficient, and simple approach was applied for the synthesis of 2,3-diaminophenazine using a new photocatalytic system of CdFe2O4/TiO2 nanoparticles in water as a benign solvent. The structure of the synthesized CdFe2O4/TiO2 nanoparticle was confirmed using different methods such as transmission electron microscope (TEM), X-ray diffraction (XRD), and magnetic measurements. It was found that the rate and yield of the photocatalytic synthesis of 2,3-diaminophenazine were improved using CdFe2O4/TiO2 nanoparticles compared to other methods.
- Ragab, Sherif S.,Badawy, Abdelrahman A.,El Nazer, Hossam A.
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- Dopamine (DA) detection in nanomolar concentration by 2,3-diaminophenazine (DAP) released from (DAP)@BioMOF-1 films
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There is a big interest in dopamine (DA) sensors, because dopamine is an important neurotransmitter and its absence results in neurological disorders. Herein we present an application of BioMOF-1, which has been used as a host to introduce 2,3-diaminophenazine (DAP) molecules, obtaining DAP@BioMOF-1 crystals. The crystals were used to prepare films that can serve as reusable sensors for detecting dopamine at nanomolar concentrations by fluorescence in both water and methanol.
- Neri-Hipólito, Javier,Lopez, Nazario,Reinheimer, Eric W.,Mas-Hernández, Elizabeth,Barrera-Díaz, Carlos E.,Varela-Guerrero, Víctor,Ballesteros-Rivas, María F.
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- Universal Nanoplatform for Formaldehyde Detection Based on the Oxidase-Mimicking Activity of MnO2 Nanosheets and the in Situ Catalysis-Produced Fluorescence Species
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Formaldehyde (HCHO) pollution is a scientific problem of general concern and has aroused wide attention. In this work, a fluorometric method for sensitive detection of formaldehyde was developed based on the oxidase-mimicking activity of MnO2 nanosheets in the presence of o-phenylenediamine (OPD). The MnO2 nanosheets were prepared by the bottom-up approach using manganese salt as the precursor, followed by the exfoliation with bovine serum albumin. The as-prepared MnO2 nanosheets displayed excellent oxidase-mimicking activity, and can be used as the nanoplatform for sensing in fluorometric analysis. OPD was used as a typical substrate because MnO2 nanosheets can catalyze the oxidation of OPD to generate yellow 2,3-diaminophenazine (DAP), which can emit bright yellow fluorescence at the wavelength of 560 nm. While in the presence of formaldehyde, the fluorescence was greatly quenched because formaldehyde can react with OPD to form Schiff bases that decreased the oxidation reaction of OPD to DAP. The main mechanism and the selectivity of the platform were studied. As a result, formaldehyde can be sensitively detected in a wide linear range of 0.8-100 μM with the detection limit as low as 6.2 × 10-8 M. The platform can be used for the detection of formaldehyde in air, beer, and various food samples with good performance. This work not only expands the application of MnO2 nanosheets in fluorescence sensing, but also provides a sensitive and selective method for the detection of formaldehyde in various samples via a new mechanism.
- Zhao, Qixia,Shen, Tong,Liu, Yujiao,Hu, Xiaojun,Zhao, Wenying,Ma, Zhangyan,Li, Peipei,Zhu, Xiaohua,Zhang, Youyu,Liu, Meiling,Yao, Shouzhuo
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- Detection of Tumor Invasive Biomarker using a Peptamer of Signal Conversion and Signal Amplification
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Inspired by the structural and functional features of proteins in cell signaling, a switchable peptide is designed in this work. This switchable peptide is named a "peptamer," and it can react to ligand binding with conformational change and activation/deactivation of catalytic ability. The peptamer is constructed by elaborately integrating several different peptide motifs with targeting and catalytic abilities. Thus, targeted binding of the peptamer to an integrin can be regulated by a synthetic ligand. Moreover, the conformational rearrangement of the peptamer induced by both integrin and the synthetic ligand can resolve in altered affinity of the peptamer for a catalytic cofactor, cupric ion. This leads to greatly contrasted efficiency of catalysis in the presence/absence of integrin. This distinct switching on/off of catalytic activity also enables a bioassay of tissue integrin expression in clinical samples of thyroid carcinoma. Experimental results reveal that the detected integrin level parallels the state of lymph node metastasis. Therefore, this simple peptide model may help to understand the structural reconfiguration of proteins involved in cellular signal transduction, as well as to provide a new means to assess protein activity under pathological conditions such as cancer. (Figure Presented).
- Li, Hao,Li, Weiwei,Liu, Fengzhen,Wang, Zhaoxia,Li, Genxi,Karamanos, Yannis
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- Copper(II) complexes as catalyst for the aerobic oxidation of o-phenylenediamine to 2,3-diaminophenazine
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Two new mononuclear copper(II) complexes [Cu (L) (NO3)2] (1) and [Cu (L) Br2] (2) where (L = bis(1-(pyridin-2-ylmethyl)-benzimidazol-2-ylmethyl)ether) are synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, UV-Visible, IR spectroscopy, EPR and cyclic voltammetry. The complexes exhibit different coordination structures; the E1/2 value of the complex (1) is found to be relatively more cathodic than that of complex (2). X-band EPR spectra at low temperature in DMF supports a tetragonally distorted complex (1) while complex (2) shows three different g values suggesting a rhombic geometry. These complexes were utilized as a catalyst for the aerobic oxidation of o-phenylenediamine to 2,3-diaminophenazine assisted by molecular oxygen. The initial rate of reaction is dependent on the concentration of Cu(II) complex as well as substrate, and was found to be higher for the nitrate bound complex, while presence of acetate anion acts as a mild inhibitor of the reaction, as it is likely to pick up protons generated during the course of reaction. The inhibition suggests that the generated protons are further required in another important catalytic step.
- Khattar, Raghvi,Yadav, Anjana,Mathur, Pavan
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- Cancer-Cell Imaging Using Copper-Doped Zeolite Imidazole Framework-8 Nanocrystals Exhibiting Oxidative Catalytic Activity
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Copper-doped zeolite imidazole framework-8 (Cu/ZIF-8) was prepared and its peroxidase-like oxidative catalytic activity was examined with a demonstration of its applicability for cancer-cell imaging. Through simple solution chemistry at room temperature, Cu/ZIF-8 nanocrystals were produced that catalytically oxidized an organic substrate of o-phenylenediamine in the presence of H2O2. In a similar manner to peroxidase, the Cu/ZIF-8 nanocrystals oxidized the substrate through a ping-pong mechanism with an activation energy of 59.2 kJ mol?1. The doped Cu atoms functioned as active sites in which the active Cu intermediates were expected to be generated during the catalysis, whereas the undoped ZIF-8 did not show any oxidative activity. Cu/ZIF-8 nanocrystals exhibited low cell toxicity and displayed catalytic activity through interaction with H2O2 among various reactive oxygen species in a cancer cell. This oxidative activity in vitro allowed cancer-cell imaging by exploiting the photoluminescence emitted from the oxidized product of o-phenylenediamine, which was insignificant in the absence of the Cu/ZIF-8 nanocrystals. The results of this study suggest that the Cu/ZIF-8 nanocrystal is a promising catalyst for the analysis of the microbiological systems.
- Keum, Changjoon,Park, Sangwoo,Lee, Sang-Yup
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- Method for rapidly synthesizing 2, 3-diaminophenazine through ultrasonic radiation catalysis
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The invention provides a method for rapidly synthesizing 2, 3-diaminophenazine through ultrasonic radiation catalysis. The method specifically comprises the following steps: preparing an o-phenylenediamine raw material solution, preparing a catalyst transition metal salt solution, mixing the raw material solution and the transition metal salt solution, and carrying out ultrasonic radiation assisted reaction in an ultrasonic reactor, and washing and purifying the reaction product. According to the synthesis process, the target compound 2, 3-aminophenazine is rapidly and efficiently synthesized by adopting an ultrasonic radiation assisted reaction mode and taking a common low-valence chemical reagent o-phenylenediamine as the raw material, the whole process is environment-friendly and safe, and the reaction yield is relatively high so that the synthesis production cost of the 2, 3-aminophenazine is greatly reduced, and the application range of the 2, 3-aminophenazine is expanded.
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Paragraph 0022-0029
(2021/07/17)
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- Visible-light-mediated synthesis of substituted phenazine and phenoxazinone using eosin y as a photoredox catalyst
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This paper describes an efficient, sustainable, one-step procedure for synthesizing substituted phenazines and phenoxazinones from commercially available ortho-substituted aromatic amines with very good yield (≥80%) in water. The procedure uses eosin Y (EY) as a photoredox catalyst at room temperature (RT). The highly reactive o-quinone-diimine or o-quinone-imine intermediate was characterized by the HR-MS technique.
- Dhar, Basab Bijayi,Dhara, Ashish Kumar,Maity, Sayantan
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supporting information
p. 3269 - 3273
(2021/05/31)
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- TEMPO-catalyzed electrochemical dehydrogenative cyclocondensation of: O -aminophenols: Synthesis of aminophenoxazinones as antiproliferative agents
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The aminophenoxazinone core is widely prevalent in natural products, dyes and pharmaceutical molecules. We report here a TEMPO-catalyzed electrosynthetic method allowing the dehydrogenative cyclocondensation of o-aminophenols. This mild and sustainable method proceeds in the absence of stoichiometric oxidants and uses an easily available organo-electrocatalyst to access pharmaceutically valuable 2-aminophenoxazinones. Mechanistic studies indicate that the electrochemically generated TEMPO+ enables the oxidative radical homo-dimerization of o-aminophenols. The application of electrosynthesis provides an approach for the synthesis of pseudo-aminophenoxazinone alkaloids with improved structural diversification and bioactivities. This journal is
- Cai, Yun-Rui,Ji, Su-Hui,Ma, Zhi-Yuan,Shonhe, Chantale,Zhou, Jianmin
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supporting information
p. 8566 - 8570
(2021/11/17)
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- A novel photochemical sensor based on quinoline-functionalized phenazine derivatives for multiple substrate detection
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A novel photochemical sensor (FQ-5) based on quinoline-functionalized phenazine derivatives was designed and synthesized. TheFQ-5showed a good response to certain pH values in a wide pH range (from 2.0 to 13.0). Particularly, at pH = 12 and 13, the fluorescence emission showed obvious enhancement, the fluorescence quantum yields could reach 80.9% and 77.0%, respectively, and the color of solution changed from yellow to purple. Meanwhile, the sensor not only showed a rapid response toward CO2, but also showed high selectivity and sensitivity for the detection ofl-Arg in buffer solution (pH = 7), and the limit of detection (LOD) was 8.1 × 10?8. Furthermore, theFQ-5-based fluorescent writing material and CO2gas reaction device were developed for the rapid detection ofl-Arg and CO2. Therefore, this work will provide a new approach for photochemical sensing in the detection of multiple substrates.
- Wei, Tai-Bao,Dong, Hong-Qiang,Ma, Xiao-Qiang,Yang, Qing-Yu,Wang, Zhong-Hui,Guan, Wen-Li,Zhang, Yun-Fei,Zhang, You-Ming,Yao, Hong,Lin, Qi
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p. 5040 - 5048
(2021/03/26)
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- Biomimics of phenazine oxidase activity of a cobalt (III)-dipyridylamine complex: Spectroscopic, structural, and computational studies?
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This manuscript demonstrates the synthesis, structural characterization, computational studies, and biomimics of the phenazine oxidase activity of a newly designed cobalt (III) complex, [Co (dpa)(dpa-H+)(N3)2]Cl2 (1) [dpa = 2,2′-dipyridylamine] under an aerobic condition. The crystal structure analysis reveals that the cobalt (III) center adopts an octahedral geometry, and the complex forms a beautiful supramolecular framework through noncovalent interactions. The cobalt (III) catalyst turns out to be a promising catalyst for the oxidative coupling of o-phenylenediamine (OPD) in oxygen-saturated methanol with an excellent turnover number, kcat = 7.85 × 103 h?1. Spectrophotometric, electrochemical, mass spectrometry, and computational analysis ensure that the course of catalysis undergoes through a catalyst-substrate complexation, facilitating the development of cobalt-iminobenzoquinone species in the solution. The computational calculations employing the density functional theory (DFT) throw a light to the mechanistic insights of the phenazine oxidase mimics. ETS-NOCV (extended transition state-natural orbitals for chemical valence) plots of the reactive intermediates portray the coordination-driven depletion of electron density from the nitrogens of OPD to cobalt center leading to the enhancement of electrophilic character on para-positioned C-atoms with respect to N-atoms of OPD, therby catalyzing the nucleophilic attack by second OPD to produce the oxidation product, 2,3-diaminophenazine (DAP). Interestingly, we are able to isolate the oxidation product of the OPD oxidation reaction as a hydrated chloride salt, DAPH+Cl? ·3H2O (2). The crystal engineering perspectives of 2 attribute the intriguing fate of the secondary chlorides for the stabilization of the oxidation product in crystalline phase.
- Biswas, Bhaskar,Choudhury, Angshuman Roy,Das, Soumik,Joshi, Mayank,Mahato, Rajani Kanta,Misra, Anirban
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- A silicon nanoparticle-based nanoprobe for ratiometric fluorescence and visual detection of glucose
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Diabetes mellitus is a chronic disease that affects human health worldwide. Monitoring of glucose levels in the blood is still vital for the early clinical diagnosis and management of diabetes. Since single-wavelength fluorescence probes are prone to being influenced by instrument fluctuations, the design of simple and cheap ratiometric fluorescence probes is urgently needed for glucose determination. Silicon nanoparticles (SiNPs) possess excellent properties, such as biocompatibility, low toxicity and good water solubility, which makes them suitable for nanosensors. Herein, we synthesized SiNPs by a one-step method that simplifies the preparation procedure, and for the first time established a novel SiNP-based nanoprobe (denoted as SiNPs/OPD/HRP/GOx) for ratiometric fluorescence and visual detection of glucose. Glucose oxidase (GOx) catalyzes glucose to produce gluconic acid and hydrogen peroxide (H2O2) under appropriate conditions. The H2O2 can oxidize o-phenylenediamine (OPD) to generate 2,3-diaminophenazine (oxOPD) in the presence of horseradish peroxidase (HRP). The oxOPD has strong fluorescence and can quench the fluorescence of SiNPs by means of the inner filter effect. With elevated glucose concentration, the fluorescence of SiNPs decreases gradually, while the fluorescence of oxOPD increases, thus achieving ratiometric fluorescence detection of glucose. Likewise, the color change with increasing amounts of glucose realizes the visual detection of glucose. This SiNP-based nanoprobe has good selectivity toward glucose and a simple preparation approach, which provides a new method for establishing glucose sensors.
- Gao, Na,Jing, Jing,Liu, Yazhou,Yang, Chunlei,Zhang, Xiaoling,Zhao, Hengzhi
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supporting information
p. 19515 - 19520
(2021/11/09)
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- Ratiometric fluorescence assay based on carbon dots and Cu2+-catalyzed oxidation of: O -phenylenediamine for the effective detection of deferasirox
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The monitoring of deferasirox (DEF) has important clinical roles in patients who need iron excretion. However, analytical methods with practicability and simplicity are limited. Moreover, ratiometric fluorescence strategies based on F?rster resonance energy transfer (FRET) from carbon dots (CDs) as a donor are rarely reported as a drug monitor. In this work, CDs with an appropriate emitting wavelength at 480 nm and excitation around 370 nm were prepared by hydrothermal approach and HCl post-treatment. O-Phenylenediamine (OPD) can be oxidized by Cu2+ to produce yellow fluorescent 2,3-diaminophenazine (oxOPD) in the system of Cu2+ and OPD (Cu-OPD). Correspondingly, a remarkable FRET from CDs to oxOPD in the system of CDs, Cu2+ and OPD (CDs-Cu-OPD) was fabricated with the quenching illustration of CDs, but emitting property of oxOPD. Attributed to the chelation ability of DEF on Cu2+, the inhibitory effects of DEF on the Cu2+-triggered oxidative capability reduced the FRET system by the decreased oxOPD. Thus, the recovered CDs at F480 and decreased oxOPD at F560 were found through a ratiometric mode by the addition of DEF in CDs-Cu-OPD for the DEF assay. The FRET behavior of CDs and oxOPD in CDs-Cu-OPD was proved clearly through the calculation of the association constant, binding constant, number of binding sites, and the distance between the donor and acceptor. Furthermore, this ratiometric method exhibited promising analytical performance for DEF with the application in real samples. The implementation of this work expands the application field of CDs and OPD oxidation in drug monitoring, and even other biological analyses through ratiometric strategy.
- Guo, Xian-Zhong,Han, Wen-Di,Huang, Zheng-Jun,Lin, Yin-Ning,Miao, Chen-Fang,Weng, Shao-Huang,Zhang, Xin-Tian
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p. 34525 - 34532
(2021/12/02)
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- A self-assembled supramolecular gel constructed by phenazine derivative and its application in ultrasensitive detection of cyanide
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In this work, we constructed a supramolecular gel (PN-G) by phenazine derivative, which can ultrasensitive detect cyanide (detection limit equals to 4.18 × 10?10 M). The decrease of fluorescent intensity displayed a linear relationship in the range of 0–0.4 equivalents of cyanide. And no significant fluorescence quenching was observed for all used interfering ions. The cyanide recognition mechanism of PN-G was verified by XRD, NMR, MS and SEM. With addition of cyanide to the supramolecular gel (PN-G), cyanide broken π-π stacking of PN-G, and then PN-G undergoes a nucleophilic addition reaction with CN?, resulting in fluorescence quenched.
- Fang, Hu,Qu, Wen-Juan,Yang, Hao-Hang,He, Jun-Xia,Yao, Hong,Lin, Qi,Wei, Tai-Bao,Zhang, You-Ming
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- Tailoring an HSO4-anion hybrid receptor based on a phenazine derivative
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A catechol-functionalized phenazine imidazole (PD) was tailored with 2,3-diaminophenazine and 3,4-dihydroxy benzaldehyde, and it served as a hybrid acceptor for capturing HSO4- anions. The selectivity and sensitivity of the PD receptor for anion sensing were studied. It was found that the PD receptor could not only display a preferable sensitivity to HSO4- ions with a "turn-off"fluorescence response, but also have a strong anti-interference ability toward other common anions, especially basic anions such as CH3COO-, HPO42-, and H2PO4-. The anion recognition mechanism of PD towards HSO4- is based on multiple hydrogen bond interactions. Finally, the strips for anion detection were prepared, which were verified to be a convenient and high-efficiency test kit for detecting HSO4- ions with the naked eye.
- Qi, Xiao-Ni,Dong, Hong-Qiang,Yang, Hai-Long,Qu, Wen-Juan,Zhang, You-Ming,Yao, Hong,Lin, Qi,Wei, Tai-Bao
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p. 1373 - 1381
(2020/11/03)
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- Water-soluble phenazine derivative as well as preparation method and application thereof
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The invention relates to a water-soluble phenazine derivative as well as a preparation method and an application thereof. The structural formula of the derivative is shown in the specification. The preparation method of the water-soluble phenazine derivative comprises the following steps: adding N, N-dimethylformamide, 2, 3-diaminophenazine, glacial acetic acid and 3, 4-dihydroxy benzaldehyde intoa reactor to obtain the phenazine derivative; in absolute ethyl alcohol, adding phenazine derivatives and sodium hydroxide into the absolute ethyl alcohol, and carrying out a stirring reaction at room temperature to obtain the water-soluble phenazine derivatives. The water-soluble phenazine derivative is used for anion recognition of a silicate ion sensor.
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Paragraph 0027; 0037-0038
(2020/10/29)
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- Waste minimized synthesis of pharmaceutically active compounds: Via heterogeneous manganese catalysed C-H oxidation in flow
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Herein, we present our results on the development of a continuous flow protocol enabling the waste minimised synthesis of relevant pharmaceuticals and natural compounds. Heterogeneous manganese catalytic systems have been used in combination with molecular oxygen to promote the C-H oxidative coupling of 2-aminophenols, benzenetriols and o-phenylenediamines to access a variety of 2-aminophenoxazin-3-ones (2a-i) and related diaminophenazines (2j-k) and purpurogallin (2l) with minimal metal contamination. Making use of safe and green cyclopentyl methyl ether (CPME), this methodology allowed a fast synthesis of fully decorated molecular entities, preserving the stability of the heterogeneous catalyst which showed minimal metal leaching, with minimal waste production (low E-factor).
- Ferlin, Francesco,Luque Navarro, Pilar María,Gu, Yanlong,Lanari, Daniela,Vaccaro, Luigi
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supporting information
p. 397 - 403
(2020/02/13)
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- Heterogeneous Manganese-Catalyzed Oxidase C?H/C?O Cyclization to Access Pharmaceutically Active Compounds
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Heterogeneous manganese-catalyzed C?H oxidative couplings were accomplished to gain access to pharmaceutically relevant 2-aminophenoxazin-3-ones and to diaminophenazine and purpurogallin moieties in excellent yields. The user-friendly K-OMS-2 oxidase strategy proved to be more versatile and robust than enzymatic catalysts-based procedures allowing a wider substrate scope and being effectively reusable as proven by leaching measurements and XRD analyses.
- Ferlin, Francesco,Marini, Alberto,Ascani, Nicola,Ackermann, Lutz,Lanari, Daniela,Vaccaro, Luigi
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p. 449 - 454
(2019/12/12)
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- Novel compound based on diaminophenazine and use thererof
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The present invention relates to a novel compound and a use thereof. More specifically, the present invention provides: a novel compound based on diaminophenazine which can effectively inhibit aggregation of tau, one of the causes of Alzheimerandprime;s disease; and a use thereof. According to the novel compound based on diaminophenazine and the use thereof, it is possible to realize an effect of producing a therapeutic agent for Alzheimerandprime;s dementia due to tau aggregation.COPYRIGHT KIPO 2020
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Paragraph 0083; 0084-0086
(2020/05/22)
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- A designed second-sphere hydrogen-bond interaction that critically influences the O-O bond activation for heterolytic cleavage in ferric iron-porphyrin complexes
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Heme hydroperoxidases catalyze the oxidation of substrates by H2O2. The catalytic cycle involves the formation of a highly oxidizing species known as Compound I, resulting from the two-electron oxidation of the ferric heme in the active site of the resting enzyme. This high-valent intermediate is formed upon facile heterolysis of the O-O bond in the initial FeIII-OOH complex. Heterolysis is assisted by the histidine and arginine residues present in the heme distal cavity. This chemistry has not been successfully modeled in synthetic systems up to now. In this work, we have used a series of iron(iii) porphyrin complexes (FeIIIL2(Br), FeIIIL3(Br) and FeIIIMPh(Br)) with covalently attached pendent basic groups (pyridine and primary amine) mimicking the histidine and arginine residues in the distal-pocket of natural heme enzymes. The presence of pendent basic groups, capable of 2nd sphere hydrogen bonding interactions, leads to almost 1000-fold enhancement in the rate of Compound I formation from peracids relative to analogous complexes without these residues. The short-lived Compound I intermediate formed at cryogenic temperatures could be detected using UV-vis electronic absorption spectroscopy and also trapped to be unequivocally identified by 9 GHz EPR spectroscopy at 4 K. The broad (2000 G) and axial EPR spectrum of an exchange-coupled oxoferryl-porphyrin radical species, [FeIVO Por+] with geff⊥ = 3.80 and geff‖ = 1.99, was observed upon a reaction of the FeIIIL3(Br) porphyrin complex with m-CPBA. The characterization of the reactivity of the FeIII porphyrin complexes with a substrate in the presence of an oxidant like m-CPBA by UV-vis electronic absorption spectroscopy showed that they are capable of oxidizing two equivalents of inorganic and organic substrate(s) like ferrocene, 2,4,6-tritertiary butyl phenol and o-phenylenediamine. These oxidations are catalytic with a turnover number (TON) as high as 350. Density Functional Theory (DFT) calculations show that the mechanism of O-O bond activation by 2nd sphere hydrogen bonding interaction from these pendent basic groups, which are protonated by a peracid, involves polarization of the O-O σ-bond, leading to lowering of the O-O σ?-orbital allowing enhanced back bonding from the iron center. These results demonstrate how inclusion of 2nd sphere hydrogen bonding interaction can play a critical role in O-O bond heterolysis.
- Bhunia, Sarmistha,Dey, Abhishek,Dey, Somdatta Ghosh,Ivancich, Anabella,Rana, Atanu
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p. 2681 - 2695
(2020/03/23)
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- A simple water-soluble phenazine dye for colorimetric/ fluorogenic dual-mode detection and removal of Cu2+ in natural water and plant samples
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Detection and removal of heavy metal ions in a variety of complex water systems using dyes remains a challenge. Here we have developed a rapid, low-cost, on-site water-soluble dye for the colorimetric/fluorogenic detection and removal of copper ions in natural water and plant samples. By comparing with dye molecule AHP, this water-soluble phenazine dye (AHPN) has a high fluorescence quantum yield and excellent coordinated ability with copper ions. AHPN can effectively remove copper ions in various natural water samples due to its strong binding ability with Cu2+. Moreover, the test strips also were fabricated and successfully used for real-time detection of Cu2+ in water with simple-to-use, low-cost, quick response and provide an obvious effect by naked-eye. All data in this experiment showed that this water-soluble phenazine dye AHPN has excellent effect on the detection and removal of Cu2+.
- Wei, Tai-Bao,Yong, Bi-Rong,Dang, Li-Rong,Zhang, You-Ming,Yao, Hong,Lin, Qi
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- Development of three ways molecular logic gate based on water soluble phenazine fluorescent ‘selective ion’ sensor
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New hydrophilic fluorescent selective ion sensor based on phenazine and phthalazine moieties, 1,1′-(phenazine-2,3-diyl)-bis(3-(1,4-dihydroxyphthalazin-6-yl)urea) (1), has been designed, synthesized and characterized. Interestingly, sensor 1 exhibits prominent “turn-on” and “turn-off” fluorogenic signaling at 580 nm towards Fe2+ & AcO? and Sr2+ & Cu2+, respectively. The fluorescence titration experiments shed light on the nature of the interaction between 1 and guest molecules (Fe2+, Sr2+, Cu2+ and AcO?), which divulge that 1 is flexible enough to orient itself according to the size of the guest molecule. Water mediated excited-state intramolecular proton transfer (ESIPT) and photo-induced electron transfer (PET) mechanisms are responsible for the dual behavior of 1, which binds with guest molecules in 1:1 stoichiometry. Based on the significant duplex fluorescence response of 1, a molecular logic gate keypad lock with sixteen “on” passwords for a storage system has been developed.
- Daniel Thangadurai,Nithya,Rakkiyanasamy
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supporting information
p. 132 - 140
(2018/12/13)
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- Peroxidase activity of new mixed-valence cobalt complexes with ligands derived from pyridoxal
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New mixed-valence cobalt complexes with ligands derived from pyridoxal were synthesized and characterized, and their application as mimetics of the peroxidase enzyme was investigated. Single-crystal X-ray diffraction was used to analyze all complex structures in the solid state and their electrochemical behavior was investigated. A reactivity pattern was observed in the complex synthesis regarding the cobalt compounds from which analogous zwitterionic derivatives were obtained. The importance of these compounds lies in understanding their behavior in an oxidizing environment and evaluating whether they can activate hydrogen peroxide to oxidize phenolic compounds. In nature, enzymes called peroxidases, which efficiently oxidize phenolic compounds, trigger many reactions involving the activation of hydrogen peroxide to oxidize organic substrates. However, these enzymes present several disadvantages, including denaturation and elevated costs. Therefore, these limitations can be overcome by expanding research into the study of synthetic catalysts for the oxidation of phenolic compounds using hydrogen peroxide, which is a highly relevant field of bioinorganic chemistry.
- Fontana, Liniquer André,Siqueira, Josiéli Demetrio,Ceolin, Joice,Iglesias, Bernardo Almeida,Piquini, Paulo Cesar,Neves, Ademir,Back, Davi Fernando
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- Acridone Derivate Simultaneously Featuring Multiple Functions and Its Applications
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Compared with plenty of single-functional molecules, multifunctional molecules are scarce and have high demand in further research. In this work, a multifunctional molecule called 10-methyl-2-amino-acridone (MAA) is presented. Interestingly, MAA simultaneously features electrochemistry, two-photon fluorescence, visible-light-induced oxidase mimic, and photoelectrochemistry (PEC) activity, and the related properties are studied in detailed. Multiple functions integrated into one molecule allow MAA to become a versatile signal probe. Therefore, the MAA acted as an electrochemical indicator to detect exosomal total protein with high sensitivity at first. In addition, MAA is used for one- or two-photon fluorescence imaging in vitro and in vivo, including cells, three-dimensional (3D) tumor spheroids, zebrafish, and exosomes. The results suggest that MAA not only possesses favorable photostability, but it is also suitable for imaging in deep tissue. Furthermore, the visible-light-induced oxidase mimic and photoelectrochemical activities of MAA are selectively inhibited by Cu2+, and the relevant mechanism is carefully analyzed. On the basis of this phenomenon, we develop a dual-modal detection strategy for detection of Cu2+ in river water. Compared with a single signal readout model, this strategy is able to avoid false positive and negative detection through two series of data mutually validating each other. Therefore, our study shows that the "multiple-in-one" MAA provides a blueprint for the investigation and application of a multifunctional organic molecule.
- Xia, Yaokun,He, Wenhui,Li, Juan,Zeng, Lupeng,Chen, Tingting,Liao, Yijuan,Sun, Weiming,Lan, Jianming,Zhuo, Shuangmu,Zhang, Jing,Yang, Huanghao,Chen, Jinghua
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p. 8406 - 8414
(2019/06/17)
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- Redox-Active Guanidines in Proton-Coupled Electron-Transfer Reactions: Real Alternatives to Benzoquinones?
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Guanidino-functionalized aromatics (GFAs) are readily available, stable organic redox-active compounds. In this work we apply one particular GFA compound, 1,2,4,5-tetrakis(tetramethylguanidino)benzene, in its oxidized form in a variety of oxidation/oxidative coupling reactions to demonstrate the scope of its proton-coupled electron transfer (PCET) reactivity. Addition of an excess of acid boosts its oxidation power, enabling the oxidative coupling of substrates with redox potentials of at least +0.77 V vs. Fc+/Fc. The green recyclability by catalytic re-oxidation with dioxygen is also shown. Finally, a direct comparison indicates that GFAs are real alternatives to toxic halo- or cyano-substituted benzoquinones.
- Wild, Ute,Hübner, Olaf,Himmel, Hans-J?rg
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supporting information
p. 15988 - 15992
(2019/11/13)
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- Mercury ion fluorescent sensor molecule, and synthesis and application thereof
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The invention relates to sensor molecule, 2-sulfydryl-oxazole [4, 5-b] phenazine, capable of performing fluorescence detection on mercury ion. The sensor molecule is prepared through the following steps: taking ethyl alcohol and water as a solvent, KOH as a catalyst and 2-sulfydryl-3-aminophenazine and carbon disulfide as substrates, so as to perform reflux reaction; performing hot suction filtration after reaction, filtering filter liquor after the filter liquor is acidized, performing vacuum drying, and performing DMF recrystallization, so as to obtain yellow green solid namely the mercury ion sensor molecule. The sensor molecule meets Hg2+ in a water-bearing system, hydrogen ion is removed from sulfydryl firstly, then sulfydryl is coordinated with mercury ion, fluorescence becomes lightblue from yellow, and a new emission peak appears in a 492nm position. In addition, mercury ion is added at a room temperature, the fluorescence of solution can rapidly become light blue (smaller than 3 seconds), and a good naked eye identification effect can be achieved. Hg2+ test paper manufactured through the sensor molecule can further conveniently and rapidly detect mercury ion in an environment system.
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Paragraph 0024
(2018/03/26)
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- Sensor molecule for identifying cyanide ions through colorimetric channel and fluorescent channel as well as preparation and application of sensor molecule
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The invention designs and synthesizes a sensor molecule 2-phenyl-1H-imidazole [4, 5-b] phenazine capable of detecting cyanide ions through a colorimetric channel and a fluorescent channel. According to the sensor molecule, firstly, a dimer is formed by an intermolecular hydrogen bond, and then, a supramolecular self-assembly system is formed between phenazine rings according to pi-pi stacking, sothat a host molecule solution is enabled to give out strong fluorescence; after CN- is added, a host has the proton removal action, so that the self-assembly system is crashed to cause fluorescence quenching, the CN- can be identified with high selectivity in a water-bearing medium, and the identification process is not interfered by other negative ions. Additionally, after the CN- is added at room temperature, the fluorescence intensity of the solution is quickly weakened (less than 3s), and the solution becomes jacinth, so that a good naked eye identification effect can be achieved. According to CN-test paper made by adopting the sensor molecule, the cyanide ions in an environmental system can be detected conveniently and fast.
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Paragraph 0031
(2018/03/26)
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- Highly selective and sensitive chemosensor based on 2,3-diaminophenazine hydrochloride for the detection of cyanide in pure water and its application in plant seed samples
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In this study, we prepared an efficient chemosensor based on 2,3-diaminophenazine hydrochloride, and it exhibited good dissolvability in water; more importantly, it could act as an efficient chemodosimeter for the selective detection of CN- in pure water. Upon reacting with CN-, 2,3-diaminophenazine hydrochloride (Q1) displayed a remarkable visible and fluorescence response simultaneously with significant changes in both absorption and fluorescence spectra. Furthermore, the absorption and fluorescence detection limits of CN- were 1.95 × 10-7 M and 1.13 × 10-9 M, respectively. For practical applications, test strips based on this chemosensor could serve as convenient CN- detection tools. The chemosensor was also successfully applied to the detection of CN- in plant seeds and several natural water samples.
- Yong, Bi-Rong,Wei, Tai-Bao,Qu, Wen-Juan,Lin, Qi,Zhang, You-Ming,Yao, Hong
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supporting information
p. 14766 - 14771
(2018/09/29)
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- Fluorescein as a Visible-Light-Induced Oxidase Mimic for Signal-Amplified Colorimetric Assay of Carboxylesterase by an Enzymatic Cascade Reaction
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We have found that fluorescein possesses high visible-light-induced oxidase mimetic activity and could transform colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into blue oxidized TMB (oxTMB) without unstable and destructive H2O2 under visible-light illumination. Instead, fluorescein uses oxygen as a mild and green electron acceptor, and its activity can be easily controlled by the switching “on/off” of visible light. In addition, the visible-light-induced catalytic mechanism was elucidated in detail and, as the main reactive species h+ and O2.? accounted for TMB oxidation. Based on the fact that fluorescein diacetate (FDA) possessed no activity and generated active fluorescein in situ in the presence of carboxylesterase (CaE), a signal-amplified sensing platform through a cascade reaction for CaE detection was constructed. Our proposed sensing system displayed excellent analytical performance for the detection of CaE in a wide linear range from 0.040 to 20 U L?1 with a low detection limit of 0.013 U L?1. This work not only changes the conventional concept that fluorescein is generally considered to be photocatalytically inert, but also provides a novel sensing strategy by tailoring the enzyme mimetic activity of fluorescein derivatives with analyte.
- Liu, Li,Sun, Chaoqun,Yang, Juan,Shi, Ying,Long, Yijuan,Zheng, Huzhi
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p. 6148 - 6154
(2018/04/06)
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- Versatile Three-Dimensional Porous Cu@Cu2O Aerogel Networks as Electrocatalysts and Mimicking Peroxidases
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A facile strategy is presented to form 3D porous Cu@Cu2O aerogel networks by self-assembling Cu@Cu2O nanoparticles with the diameters of ca. 40 nm for constructing catalytic interfaces. Unexpectedly, the prepared Cu@Cu2O aerogel networks display excellent electrocatalytic activity to glucose oxidation at a low onset potential of ca. 0.25 V. Moreover, the Cu@Cu2O aerogels also can act as mimicking-enzymes including horseradish peroxidase and NADH peroxidase, and show obvious enzymatic catalytic activities to the oxidation of dopamine (DA), o-phenyldiamine (OPD), 3,3,5,5-tetramethylbenzidine (TMB), and dihydronicotinamide adenine dinucleotide (NADH) in the presence of H2O2. These 3D Cu@Cu2O aerogel networks are a new class of porous catalytic materials as mimic peroxidases and electrocatalysts and offer a novel platform to construct catalytic interfaces for promising applications in electrochemical sensors and artificial enzymatic catalytic systems.
- Ling, Pinghua,Zhang, Qiang,Cao, Tingting,Gao, Feng
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supporting information
p. 6819 - 6824
(2018/05/08)
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- Novel riboflavin-inspired conjugated bio-organic semiconductors
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Flavins are known to be extremely versatile, thus enabling routes to innumerable modifications in order to obtain desired properties. Thus, in the present paper, the group of bio-inspired conjugated materials based on the alloxazine core is synthetized using two efficient novel synthetic approaches providing relatively high reaction yields. The comprehensive characterization of the materials, in order to evaluate the properties and application potential, has shown that the modification of the initial alloxazine core with aromatic substituents allows fine tuning of the optical bandgap, position of electronic orbitals, absorption and emission properties. Interestingly, the compounds possess multichromophoric behavior, which is assumed to be the results of an intramolecular proton transfer.
- Richtar, Jan,Heinrichova, Patricie,Apaydin, Dogukan Hazar,Schmiedova, Veronika,Yumusak, Cigdem,Kovalenko, Alexander,Weiter, Martin,Sariciftci, Niyazi Serdar,Krajcovic, Jozef
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- Inorganic-organic covalent hybrid of polyoxometalate-calixarene: Synthesis, characterization and enzyme mimetic activity
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The inorganic-organic hybrid based on covalently attached trilacunary phosphotungstate and calixarene conjugate (POM-Calix hybrid) has been synthesized via facile click chemistry approach. The characterization studies showed that both the moieties are present together in the hybrid upon covalent modification. The morphology of the hybrid was studied by SEM, TEM and AFM analyses suggesting spherical shaped nanoparticles of 40–60 nm size for the hybrid. The POM-Calix hybrid was successfully employed to demonstrate peroxidase-like activity for the oxidation of the model substrate, viz., o-phenylenediamine (OPD), for the enzyme. The activity of the POM-Calix hybrid was ～170% greater than that exhibited by simple POM and this is mainly attributed to the introduction of hydrophobic character by the covalently attached calixarene conjugate and the hydrophobicity is supported by the contact angle measurement. From the kinetic studies, the Michaelis constants, Km and Vmax were estimated to be 2.55 mM and 0.756 × 10?8 M s?1, respectively. It was observed that, the POM-Calix hybrid facilitates the formation of [rad]OH radicals when treated with H2O2 which eventually results in the oxidation of the substrate. The POM-Calix hybrid exhibits excellent enzyme-like activity over a wide pH range, which would enable its bio-applications at physiological conditions.
- Narkhede, Nilesh,Uttam, Bhawna,Rao, Chebrolu Pulla
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p. 337 - 342
(2018/09/11)
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- Fluorescent probe for detecting hydrogen peroxide with aggregation-induced emission characteristics as well as preparation method and application of the fluorescent probe
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The invention discloses a fluorescent probe for detecting hydrogen peroxide with aggregation-induced emission characteristics as well as a preparation method and an application of the fluorescent probe. The fluorescent probe can be used for detecting hydrogen peroxide and can also be used as a HRP chromogenic substrate in immunoassay. The fluorescent probe is composed of two o-phenylenediamine groups which specifically recognize hydrogen peroxide (H2O2) and aggregation-induced emission molecules. Due to the fact that in the presence of the horseradish peroxidase (HRP), the o-phenylenediamine can be subjected to redox reaction with hydrogen peroxide to form a phenazine structure, namely the small molecule is changed into macromolecule with stronger conjugated structure, so that the rotationin the molecules cannot be free, and the fluorescence is enhanced. The preparation method is simple, the principle is novel, the detection limit is low, the sensitivity is good, and the rapid detection can be realized. Meanwhile, the fluorescent probe can be used as a substrate for HRP in immunoassay, and is safe, stable and efficient.
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Paragraph 0036
(2019/01/04)
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- Mercaptooxazole-phenazine based blue fluorescent sensor for the ultra-sensitive detection of mercury(II) ions in aqueous solution
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Herein, a mercury(ii) ion fluorescent sensor (Z-3) with high sensitivity and immediate response is designed and synthesized. The sensor uses the phenazine group as a luminophore and sulfhydryl as a recognition moiety. The sensor is easily synthesized and it exhibits a remarkable blue shift with Hg2+. Correspondingly, its fluorescence color changes from yellow to blue. In addition, the low naked eye detection limit (10-5) of the sensor allows the identification of concentration limits. Moreover, the sensor could detect mercury(ii) ions over a wide pH range (from 2 to 8), which indicates that the detection can be carried out in aqueous systems. In addition, test strips are fabricated, which could act as a convenient pathway for the recognition of Hg2+.
- Zhang, Hai-Li,Li, Wen-Ting,Qu, Wen-Juan,Wei, Tai-Bao,Lin, Qi,Zhang, You-Ming,Yao, Hong
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p. 47547 - 47551
(2017/10/19)
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- Sensor molecule for recognizing mercury ions with colorimetric fluorometric dual channel as well as synthesis and application thereof
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The invention designs and synthesizes a sensor molecular for recognizing mercury ions with colorimetric fluorometric dual channel, namely 2-cyanomethyl-imidazole[4,5-b]phenazine. The sensor molecule is obtained by adopting normal butanol as a solvent and 2,3-diaminophenazine and ethyl cyanoacetate as a substrate to perform reflux reaction, performing the suction filter after the reaction and vacuum drying. When cation solutions are respectively added into a sensor molecular DMSO-H20 solution, the color of the solution immediately turns light only when Hg is added, the strong yellow fluorescence is completely quenched, so that the sensor molecule can specifically and selectively recognize Hg by virtue of fluorescence in an aqueous solution, the recognition process is not interfered with other cations. In addition, when the mercury ions are added under the room temperature, the fluorescence strength of the solution can be rapidly weakened (less than 3 seconds), and a good naked-eye recognition effect can be achieved. Hg test paper produced by using the sensor molecule can conveniently and rapidly detect the mercury ions in an environmental system.
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Paragraph 0026
(2018/01/11)
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- Phenazine-based colorimetric and fluorescent sensor for the selective detection of cyanides based on supramolecular self-assembly in aqueous solution
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Taking advantages of both the well-known phenazine structure and the mechanism of the supramolecular self-assembly and deprotonation process, the fluorescent and colorimetric sensor (ZL) was designed and synthesized, behaving as a circulation utilization (above 10 times) receptor for selective detection of cyanide anion (CN?) in aqueous media. Upon the addition of CN?, the sensor displayed obvious color changes from yellow to jacinth by naked eyes and the fluorescence immediately quenched (?10?s). With respect to other common anions, the sensor possessed high selectivity and sensitivity (0.05?μM) for cyanide anions. In addition, the test strips of ZL were fabricated, which could serve as practical colorimetric and fluorescent sensor for “in-the-field” measurements.
- Zhang, Hai-Li,Wei, Tai-Bao,Li, Wen-Ting,Qu, Wen-Juan,Leng, Yan-Li,Zhang, Jian-Hui,Lin, Qi,Zhang, You-Ming,Yao, Hong
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p. 117 - 124
(2016/12/26)
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- Sensitive and Selective Fluorescent and Colorimetric Sensor for Ag+ Based on the Supramolecular Self-Assembly in Semi-Water
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Specific recognition of ultratrace levels of ions in semi-water using super-quicker methods is still a challenge for environmental monitoring. Herein we report a fluorescent and colormetric sensor (ZH) based on supramolecular self-assembly, whose structure was destroyed by the addition of ultratrace of silver ions. The process promoted either naked eye visible color changes or fluorescence intensity quenched in conjunction with a wide pH range. Systematic studies revealed very high selectivity (0.07 μmol/L) for silver ions, and other common cations, e.g., Hg2+, Cu2+, Cd2+, Pb2+ had nearly no influence on the sensing behavior. This sensor also served as a multiple use of component in sensing materials by addition of I? into the mixture of ZH and Ag+ (about 5 times). What's more, ZH containing filter paper emerged distinct color and fluorescence changes upon exposure to silver (Ag+), which could be used as a portable method to undertake field testing for Ag+.
- Wei, Taibao,Zhang, Haili,Li, Wenting,Qu, Wenjuan,Su, Junxia,Lin, Qi,Zhang, Youming,Yao, Hong
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p. 1311 - 1316
(2017/09/02)
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- Mimicking horseradish peroxidase and oxidase using ruthenium nanomaterials
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Although important progress has been achieved for the study of noble metal-based enzyme-like catalysts, there are rare reports on the enzyme mimicking applications of ruthenium nanoparticles (Ru NPs). In this work, we investigated the horseradish peroxidase (HRP) and oxidase mimetic activity of Ru NPs. Mimicking HRP, Ru NPs could catalyze the oxidation of substrates 3,3,5,5-tetramethylbenzidine (TMB), o-phenylenediamine (OPD) and dopamine hydrochloride (DA) in the presence of exogenously added H2O2 to generate the products with blue, yellow and orange colors, respectively. We also report the first evidence that Ru NPs possess intrinsic oxidase-like activity, which could catalyze the oxidization of TMB and sodium l-ascorbate (NaA) by dissolved oxygen. The HRP-like and oxidase-like activities of Ru NPs were found to be related to the concentrations of Ru NPs. The catalytic mechanism was analyzed by electron spin resonance spectroscopy (ESR), which suggested that the enzyme mimicking activities of the Ru NPs might originate from their characteristic of accelerating electron transfer between substrates and H2O2 or O2. Our findings offer a better understanding of enzyme-mimicking Ru NPs and should provide important insights for future applications.
- Cao, Gao-Juan,Jiang, Xiumei,Zhang, Hui,Croley, Timothy R.,Yin, Jun-Jie
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p. 52210 - 52217
(2017/11/22)
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