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基于G-四联体/血红素形成的DNA酶催化增敏鲁米诺-H2O2发光反应原理,建立了微流控顺序注射化学发光检测K+的新方法。在K+的促进作用下,富含鸟嘌呤的寡核苷酸PS5.M折叠成G-四联体,并对血红素表现出较高的亲合力,形成DNA酶,显著地增强血红素的类辣根过氧化物酶活性,催化鲁米诺-H2O2化学发光反应。在优化的实验条件下,化学发光检测K+的线性范围为1.0~700μmol·L-1,检出限为0.54μmol·L-1,用100μmol·L-1的K+形成的DNA酶连续测定10次,相对标准偏差(RSD)为1.61%。常见的碱金属和碱土金属离子均无显著干扰。该方法可用于真实水样中K+的分析,测定结果与原子吸收法一致。 相似文献
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The signal amplification for analytical purposes has considerable potential in detecting trace levels of analytes for clinical, security or environmental applications. In the present report a strategy based on a sandwich type immunoassay system was designed for the detection of hepatitis B surface antigen which exploits the specific affinity interaction between streptavidin and biotin recognition systems. The method involves the specific coupling of multi-functionalized gold nanoparticles (bearing biotin and luminol molecules) to the streptavidin modified by secondary antibody. The chemiluminescent signal is produced by the gold nanoparticles in the presence of HAuCl4 as catalyst and hydrogen peroxide as oxidant. The immunosensor was able to detect hepatitis B surface antigen in the linear concentration range from 1.7 to 1920 pg mL−1 and the detection limit of 0.358 pg mL−1, at signal/noise = 3. 相似文献
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Chemiluminescence (CL) is a luminescence phenomenon originated by a “chemical reaction.” CL provides a basis for real-time imaging technology in materials science. In fact, a CL reaction is easily triggered in general and makes it possible to track its progress in a target material by highly sensitive photon detection. Recently, real-time CL imagings became breakthrough techniques for analyzing the molecular mechanisms of failures of polymeric materials and of reactions and phase transitions in soft crystals. In the CL imaging techniques, adamantylideneadamantane 1,2-dioxetane (Adox) has been adopted as a stable core structure of chemiluminophores. That is, Adox is an essential seed compound to design a chemiluminophore with a desired molecular function. To support developments of real-time CL imaging techniques, we review the chemistry of Adox as a representative stable chemiluminophore including scientific history and utilities of Adox and its derivatives. 相似文献
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Chaimae Bariki Fabien Halter Fabien Thiesset Christian Chauveau Iskender Gökalp Ketana Teav Sina Kheirkhah Adam M. Steinberg 《Proceedings of the Combustion Institute》2019,37(2):1911-1918
Simultaneous measurements of temperature, CH* and OH* chemiluminescent species are carried out to explore the impact of stretch rate and curvature on the structure of premixed flames. The configuration of an initially flat premixed flame interacting with a toroidal vortex is selected for the present study and reasons for this choice are discussed. Lewis number effects are assessed by comparing methane and propane flames. It is emphasized that the flame structure experiences very strong variations. In particular, the flame is shrunk (broadened) in the initial (final) period of the interaction with the vortex where strain rate (curvature) contribution of the stretch rate is predominant. By further analysing independently the thickness of the preheat and reaction zones, it is shown that for propane flames, not only the former but also the latter is significantly altered in zones where the flame curvature is negative. Changes in the reaction zone properties are further emphasized using CH* and OH* radicals. It is demonstrated that higher thermal diffusivity plays a significant role around curved regions, in which the enhanced diffusion of heat leads to a strong increase of CH* compared to OH* intensity. As an overall conclusion, this study suggests that it would be interesting to reassess the internal flame structure at lower and moderate Karlovitz numbers since changes might appear for a moderate vortex intensity with typical size much larger than the flame thickness. 相似文献
7.
Angana Goswami 《光谱学快报》2013,46(5):253-260
Bioluminescence emissions from fireflies have been well-studied for over a century. From the apparent features of the emitted light, conclusions have been drawn and hypotheses put forward on the characteristics of the highly efficient light emitting system. The basic emitter oxyluciferin, being chemically unstable, is difficult to study in isolation and, therefore, its analogs have been prepared and analyzed. In this letter, the lifetimes of the excited-state emitter oxyluciferin are measured, and an inference is drawn on the chemiluminescence reaction in vivo. The light from the Indian species of firefly Luciola praeusta contains three color-sectors: green, yellow, and red, and hence three optical filters are used to study time-resolved emissions from these sectors at different temperatures. All the three color-sectors are observed to be temperature sensitive in the time domain. An exponential variation of lifetime with temperature is observed for the emissions in these three regions. 相似文献
8.
AHMED Khan MUHAMMAD Asghar MOHAMMED Yaqoob MASOOD Ahmed Siddiqui SAMAR Ali 《高等学校化学研究》2021,37(3):629-638
Asensitive and selective method employing chemiluminescence(CL) coupled with flow injection(FI) is reported for nalbuphine hydrochloride(NAL) assay in pharmaceutical formulations. The enhancement effect of NAL on the CL reaction between tris(2,2'-bipyridyl)ruthenium(II) chloride-diperiodatocuprate(III) {Ru[(bpy)3]2+-Cu(III) complex} in acidic medium is used as analytical measurement. The optimal conditions of the CL reaction were sulfuric acid 1.0×10-3 mol/L, Ru[(bpy)3]2+ 7.5×10-5 mol/L, Cu(III)/Ag(III) complexes 4.0×10-4/5.0×10-4 mol/L, sample loop volume of 120 μL and flow rate of 2.5 mL/min. The sensitivities of the method in terms of detection(S/N=3) and quantification(S/N=10) limits are 5×10-4 and 0.001 ppm(1 ppm=1 mg/L), respectively. The linear response of the instrument in the form of CL intensity with respect to NAL concentration is over the range 0.001-15.0 ppm(R2=0.9999) with relative standard deviation from 0.8% to 3.2% and injection throughput of 120 injection/h. The applications of the method include the quantitative analysis of NAL in pharmaceutical injection samples. Variations and the average results of the proposed method are not signi-ficantly different from the results of a reported method by applying F- and paired student t-test. The most likely CL reaction mechanism is written in accordance with spectrophotometric and CL studies. 相似文献
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The determination of dimethoate using either its native chemiluminescent (CL) properties or its photoinduced chemiluminescence obtained by irradiation with a 15 W low-pressure mercury lamp was studied. Thereby, two flow injection systems (FIA) with and without irradiation were exhaustively optimized and their analytical characteristics studied. Better sensitivity and selectivity was found in absence of irradiation, due to the enhancing effect of hexadecylpyridinium chloride (HPC), which acted as a sensitizer. In the developed FIA-CL system, the alkaline hydrolysis of dimethoate with NaOH was performed on-line in presence of HPC. The oxidation of the product of hydrolysis with Ce(IV) in hydrochloric medium induced chemiluminescence. The method provided a limit of detection of only 0.05 ng mL−1 without any pre-treatment. However, the combination with solid phase extraction allowed the removal of some potential interferents as well as the preconcentration of the pesticide. Finally, the developed method was successfully applied to natural waters with recoveries between 95 and 108%. 相似文献
10.
《Analytical letters》2012,45(9):2059-2064
Abstract Peroxyoxalate chemiluminescence is used for the determination of pentachlorophenol and 1-naphthol in soil. 1-Naphthol is brominated to make it amenable to the procedure. Calibration curves are linear over concentration ranges spanning four orders of magnitude and limits of detection are at the micromolar level. the processes can be carried out in the soil without prior extraction of the analytes. 相似文献