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- 摘要
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- 实验方案
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In-Parallel Polar Monitoring of Chemiluminescence Emission Anisotropy at the Solida??Liquid Interface by an Optical Fiber Radial Array
摘要： Chemiluminescence (CL) detection is widely employed in biosensors and miniaturized analytical devices since it offers high detectability and flexible device design (there are no geometry requirements for the measurement cell, except the ability to collect the largest fraction of emitted photons). Although the emission anisotropy phenomenon for an emitting dipole bound to the interface between two media with different refractive index is well known for fluorescence, it is still poorly investigated for CL reactions, in which the excited-state reaction products can diffuse in solution before the photon emission event. In this paper, we propose a simple method for the real-time evaluation of the CL emission anisotropy based on a radial array of optical fibers, embedded in a poly(methyl methacrylate) semicylinder and coupled with a Charge-Coupled Device (CCD) camera through a suitable interface. The polar-time evolutions of the CL emission have been studied for catalyzing enzymes immobilized onto a solid surface (heterogeneous configuration) or free in solution (homogeneous configuration). Evidence of the anisotropy phenomenon is observed, indicating that the lifetime of the excited-state products of the enzyme-catalyzed reactions is shorter than the time required for their diffusion in solution at a distance at which the CL can be considered isotropic. These results open new perspectives in the development of CL-based miniaturized analytical devices.
关键词： CCD camera detector,chemiluminescence,emission anisotropy,multimode optical fiber
更新于2025-09-16 10:30:52
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OH planar laser-induced fluorescence measurement for H<sub>2</sub>/O<sub>2</sub> jet diffusion flames in rocket combustion condition up to 7.0 MPa
摘要： This study focuses on the application of OH planar laser-induced fluorescence (OH-PLIF) in high-pressure rocket combustion conditions, up to 7.0 MPa. The signal to noise ratio of PLIF degrades in high-pressure combustion owing to effects such as line broadening and interference from intense chemiluminescence. The OH(2,0) band excitation method was applied to obtain the OH(2,1) fluorescence emitted near 290 nm and filter out the intense OH(0,0) band chemiluminescence emitted near 308 nm. The gaseous H2/O2 (GH2/GO2) jet diffusion flame was formed using a recessed coaxial shear injector. The GH2/GO2 injection Reynolds number, Re (ReH2/ReO2 ≈ 2320/22800–4660/45600), was varied to examine the variation of the flame structure and reaction zone thickness under each pressure condition Pc, and Re injection condition. In addition, the variation of the experimentally derived full width at half maximum (FWHM) of the radial OH distribution, ?OH, with the Damk?ehler number, Da, was compared with that of the simulated FWHM of the OH mole fraction, ?OH-SIM. The OH distribution was clearly observed in the instantaneous PLIF image while eliminating the intense OH chemiluminescence even in the highest pressure condition of 7.0 MPa, which is a pressure higher than any of the previous OH-PLIF studies conducted on rocket combustion. The flame structure showed the typical characteristics of a turbulent jet diffusion flame and depended on Re rather than on the chamber pressure Pc. The variation of ?OH with Da corresponded qualitatively with ?OH-SIM and showed the characteristics of flame stretch in the vicinity of the injector.
关键词： Jet diffusion flame,High-pressure combustion,Laser-induced fluorescence,Chemiluminescence,OH(2,0) band excitation
更新于2025-09-11 14:15:04
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Fabrication of a new peroxyoxalate chemiluminescence system containing the Cy3 fluorophore and its application to carvedilol detection
摘要： Cy3 is a dye that has been widely applied in fluorescence microscopy and single molecule detection due to its low hydrophobicity and intense fluorescence emission. As a new application, this study proposes using Cy3 as the fluorophore of a peroxyoxalate chemiluminescence system. The system relies on the oxidative reaction of bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with H2O2 in the presence of imidazole, as the catalyst, to produce dioxetane via a chemically initiated electron exchange luminescence (CIEEL) process, excite Cy3 by the excess energy of the dioxetane and permit Cy3 to emit yellow light. The chemiluminescence behavior of the system is investigated using different concentrations of TCPO, imidazole, the oxidant and Cy3 and by considering non-linear least squares curve fitting of the obtained intensity–time profiles into the pooled intermediate model. The evaluated kinetic parameters include experimental and theoretical maximum intensity, the rise and fall rate constants of the chemiluminescence process, experimental and theoretical time required to reach the maximum intensity and total emission yield. Finally, the developed system is adopted to detect a drug, i.e., carvedilol, in different pharmaceuticals. Under the optimal conditions, the system can provide a linear response for determination of 3 × 10? 7 to 3 × 10? 5 M carvedilol (r > 0.9869, n = 6) and a detection limit of 1.21 × 10? 7 M. The relative standard deviation of the detection results for six repetitive determinations is below 3.47% and the obtained recoveries are 99.6% and 101.9%.
关键词： Cy3,Fluorophore,Carvedilol,Peroxyoxalate chemiluminescence
更新于2025-09-10 09:29:36
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A Chemiluminescent Probe for HNO Quantification and Real-time Monitoring in Living Cells
摘要： Azanone (HNO) is a reactive nitrogen species with pronounced biological activity and high therapeutic potential for cardiovascular dysfunction. A critical barrier to understanding the biology of HNO and furthering clinical development is quantification and real-time monitoring of delivery in living systems. Here, we describe the design and synthesis of the first chemiluminescent probe for HNO, HNOCL-1, which can detect HNO generated from as low as 138 nM Angeli's salt with high selectivity based on reaction with a phosphine group to form a self-cleavable azaylide intermediate. We have capitalized on this high sensitivity to develop a generalizable kinetics-based approach, which provides real-time quantitative estimates of HNO concentration that show good agreement with computational simulations. This method can be used to quantify picomolar HNO concentrations generated from hydrogen sulfide (H2S) and nitric oxide (NO). HNOCL-1 can monitor dynamics of HNO delivery in living cells and tissues, demonstrating the versatility of this method for tracking HNO in living systems.
关键词： phosphine,chemiluminescence,nitroxyl,bioanalytical
更新于2025-09-10 09:29:36
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Homogeneous Electron Transfer Reactions of Electrochemically Generated Species in Electrogenerated Chemiluminescence; 電気化学発光における電極反応の後続反応;
摘要： Electrogenerated Chemiluminescence (ECL) involves electrode reactions and the following homogeneous electron transfer reactions which resulted in a light emission. In this integrated research paper, we focused on the homogeneous electron transfer reactions to form excited states of some luminescent molecules. The Marcus theory was used to estimate ratios of the electron-transfer rate constants between a radical cation and anion to generate the lowest excited singlet and triplet states. In addition, the ECL behavior using tripropylamine as a coreactant was demonstrated by simulating the electrochemical and homogeneous electron transfer reactions with a finite element method. Although coreactants are useful to form excited species, because of complicated reactions in bulk, analyzing the ECL response such as relationship between the current-voltage and ECL intensity curves depending on the redox potentials of luminescent molecules and coreactants is quite difficult. It was shown that the simulations were very useful to understand the ECL response depending on the redox potentials of the coreactant and luminescent molecules.
关键词： Marcus theory,homogeneous electron transfer,Electrogenerated Chemiluminescence,tripropylamine,finite element method
更新于2025-09-09 09:28:46
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Reactive Species Detection in Biology || UV–Vis Absorption and Chemiluminescence Techniques
摘要： Spectrophotometric techniques involving ultraviolet and colorimetric detection offer a convenient way of detecting reactive species (RS) formation due to the prevalence of UV-Vis spectrophotometer in research laboratories. Conventional spectrophotometric measurement of RS exploits their unique chemical reactivity with a small organic molecule and/or enzyme that has specificity to these RS where formation (or disappearance) of absorption peak/s at a particular wavelength is observed at the UV to the visible region of the electromagnetic spectrum. Direct detection of O2 from xanthine oxidase in the past involves rapid-freeze technique using electron paramagnetic resonance (EPR) spectroscopy. At the same time, spectrophotometric detection of O2 generated from xanthine oxidase/xanthine system was also employed for the investigation of the enzymatic property of superoxide dismutase (SOD) where the O2 levels were measured through reduction of ferricytochrome c, tetranitromethane, or oxidation of epinephrine to adenochrome. Several approaches have been developed since then to improve sensitivity with the use of submicromolar probe concentration thus allowing minimal interferences of the probe on the biological process being investigated. Specificity has also been improved to increase the reaction rate of probes to certain RS through synthesis of new and innovative analogues that exploit the unique chemistry between the probe and RS. Chromophore stability was also achieved through improved molecular design, optimized experimental conditions, or addition of supramolecular reagents since chromophores impart inherent thermodynamic stability as a function of its chemical structure, solvent polarity, pH, temperature, or due to presence of oxido-reductants or other reactive substances. Improved sample preparation and high-throughput analysis were also developed in order to maximize efficiency in the measurement markers of oxidative stress and determination of antioxidant capacity (AOC) of known molecules, food, biological fluid, or tissue. Therefore, spectrophotometric techniques for RS measurement have found broad application in the fields of biomedical research, clinical chemistry, plant biology, food chemistry, environmental chemistry, radiation chemistry, pharmaceuticals, toxicology, or material science to name a few, or just simply for the investigation of RS production in simple chemical systems. However, unlike the fluorescence probes, spectrophotometric as well as most applications of chemiluminescence probes do not provide spectrospatial image of the RS localization in cells, hence, one cannot deduce the site of radical production unless multiple probes and/or inhibitors are used with varying compartmentalization property (i.e., extracellular or intracellular). For example, in the investigation of radical production in cellular NADPH oxidase, several methods had been suggested such as measurement of O2 consumption, use of SOD-ferricytochrome c and horseradish peroxidase (HRP)/inhibitable probe such as Amplex Red for extracellular O2 and H2O2, respectively, and the HPLC analysis of the 2-OH-E marker for the quantification of intracellular O2.
关键词： Clinical Chemistry,Oxidative Stress,Spectrophotometric Techniques,Environmental Chemistry,Reactive Species,Antioxidant Capacity,Biomedical Research,Chemiluminescence,Superoxide Dismutase,UV-Vis Absorption
更新于2025-09-04 15:30:14
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A brief review on mass/optical spectrometry for imaging analysis of biological samples
摘要： Imaging analysis, especially bioimaging analysis, has been a hot research topic in recent years. There are numerous imaging analysis techniques for diverse applications of a wide spectrum of samples, with their unique advantages and disadvantages, and there are several related reviews published yearly. Among them, imaging mass spectrometry (IMS) technique for studying the distribution of molecular or ionic species at the level of tissue, cell, or subcellular, with its main feature of combining mass spectra for molecular identification and image visualization for quick and convenient analysis. The IMS does not require chemical labeling or complex sample preparation. This review, mainly focuses on the popular emerging IMS technique, including related ionization techniques in connection with their IMS applications, and some unique optical imaging techniques such as chemiluminescence imaging and dual-modal bioimaging for biological sample analysis, with 105 related recent references.
关键词： laser,multimodal bioimaging,biomedical imaging,chemiluminescence,optical spectrometry,bioimaging analysis,dual-modal bioimaging,mass spectrometry,Imaging analysis,ionization source
更新于2025-09-04 15:30:14
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Mechanism of the Ru(bpy)32+ single-bubble sonochemiluminescence in neutral and alkaline aqueous solutions
摘要： The paper addresses sonochemiluminescence generated by a single bubble levitating in neutral and alkaline aqueous solutions of Ru(bpy)3Cl2. Generally, this sonochemiluminescence was found to obey the rules identified previously for multi-bubble sonochemiluminescence and to be described by reactions between the Ru(bpy)3·2+ ion and the radical products Н·, ОН·, and eaq in solution. These products arise in the bubble upon decay of low-temperature plasma and migrate to the solution as the bubble intensively moves and its spherical shape is distorted as a result of a change in the acoustic pressure above and below the stability threshold. Some radicals can also get into the solution from a stationary bubble. The difference from the multibubble sonochemiluminescence is that luminescence intensity has a higher contribution of the re-emission effect of bubble luminescence by Ru(bpy)32+ ions. In solutions with low concentrations of the complex (10–6-10–5 М) and the bubble being stationary, this effect provides up to 2/3 of the total ruthenium emission intensity. It is suggested that the hydrated electrons, which increase the yield of sonochemiluminescence, can be generated upon single-bubble sonolysis of neutral solutions rather than only upon conversion of H atoms in alkaline solutions, as is the case for the multi-bubble sonochemiluminescence.
关键词： tris-bipyridyl ruthenium(II) complex,chemiluminescence,single-bubble sonoluminescence
更新于2025-09-04 15:30:14
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HONO measurement by differential photolysis
摘要： Nitrous acid (HONO) has been quantitatively measured in situ by differential photolysis at 385 and 395 nm, and subsequent detection as nitric oxide (NO) by the chemiluminescence reaction with ozone (O3). The technique has been evaluated by Fourier transform infrared (FT-IR) spectroscopy to provide a direct HONO measurement in a simulation chamber and compared side by side with a long absorption path optical photometer (LOPAP) in the field. The NO–O3 chemiluminescence technique is robust, well characterized, and capable of sampling at low pressure, whilst solid-state converter technology allows for unattended in situ HONO measurements in combination with fast time resolution and response.
关键词： LOPAP,HONO,FT-IR,chemiluminescence,differential photolysis
更新于2025-09-04 15:30:14
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Electrogenerated Chemiluminescent Chemodosimeter Based on a Cyclometalated Iridium(III) Complex for Rapid and Sensitive Detection of Thiophenol
摘要： Thiophenol is the simplest aromatic thiol that is utilized for various applications in industry and agriculture. However, it should be used with care because thiophenol is readily absorbed into the human body by inhalation and ingestion, which leads to serious internal injuries. Thus, there is an urgent need for real-time and accurate monitoring of thiophenol. Despite remarkable advantages of electrogenerated chemiluminescence (ECL) analysis, ECL thiophenol probes have never been reported. Herein, a new strategy for the rapid detection of thiophenol using an ECL turn-on chemodosimeter based on a cyclometalated Ir(III) complex is described. This analytical system showed superior sensitivity (limit of detection (LOD) value, 3.8 nM) in comparison to the conventional fluorescence method. In addition, our system exhibited remarkable selectivity and reaction rate towards thiophenol over other analytes. Moreover, it was successfully applied to quantify thiophenol in real water samples, providing a new proof-of-concept for field-monitoring based on ECL.
关键词： Cyclometalated Ir(III) complex,Electrogenerated chemiluminescence,Chemodosimeter,Sensitive detection,Thiophenol
更新于2025-09-04 15:30:14