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41.
A sensitive chemiluminescence method for the determination of acetylspiramycin is presented. It is based on the greatly enhancive effect of acetylspiramycin on the chemiluminescence reaction between luminol and hydrogen peroxide in the flow system. The increase in chemiluminescence intensity was linearly proportional to the acetylspiramycin concentration in the range from 10pg·mL–1 to 2.0ng·mL–1 (r2=0.9979). The detection limit was 3pg·mL–1 (3). At a flow rate of 2.0mL·min–1, the process of determination, including sampling and washing, could be performed in 0.5 min, and the relative standard deviations of seven replicates are less than 5.0%. The proposed method was applied successfully to the determination of acetylspiramycin in pharmaceutical preparations, human urine and serum without pre-treatment. It was found that the excretive ratio of acetylspiramycin reached its maximum 2.0 hours after having been administered orally, and the excretive ratio in 12.0 hours was 8.4. 相似文献
42.
流动注射化学发光传感器测定抗坏血酸 总被引:9,自引:0,他引:9
基于抗坏血酸抑制KMnO4-鲁米诺体系化光反应这一效应,设计出一种简便,快速,灵敏度高的消耗型化学发光抗坏血酸传感器。该传感器线性响应范围为1.0*10^-5-4.0*10^-3g/L;相对标准偏差为2.3%(1.0*10^-4g/L,n=11); 相似文献
43.
A rapid flow-injection method with chemiluminescence (CL) detection is described for the determination of glutathione (GSH).
The method is based on the CL reaction of luminol and hydrogen peroxide. GSH can greatly enhance the chemiluminescence intensity
in 0.1 mol/L borax–sodium hydroxide buffer solution (pH = 9.7). The maximum CL intensity was directly proportional to the
concentration of GSH in the range 3.0 × 10−7–2.0 × 10−5 mol/L, and the detection limit was 6.8 × 10−8 mol/L. The relative standard deviation was 3.4% for 5.0 × 10−6 mol/L of GSH (n = 11).
Received October 23, 2001; accepted June 18, 2002 相似文献
44.
测定核黄素的化学发光新方法 总被引:4,自引:0,他引:4
研究了核黄素的化学发光性质,建立了一种测定核黄素的化学发光新方法,并应用于实际样品中核黄素的测定,与文献相比,本方法无需避光,而且分析体系和样品处理简单;干扰小,牛血清白蛋白、抗坏血酸、天冬氨酸等8种生物有机物质和 Cu(Ⅱ)、Zn(Ⅱ)、Fe(Ⅲ)等15种常见金属离子的允许量较大;核黄素溶液浓度在0. 10~50 mg/L范围内,与化学发光强度成正比,方法线性范围宽;测定1.0mg/L核黄素溶液12次,求得相对标准偏差为2.9%,方法精密度高;方法的检测限为0.075 mg/L,灵敏度高。 相似文献
45.
Andreas Rahm Evgeni M. Kaidashev Heidemarie Schmidt Mariana Diaconu Andreas Pöppl Rolf Böttcher Christoph Meinecke Tilman Butz Michael Lorenz Marius Grundmann 《Mikrochimica acta》2006,153(1-2):21-25
A flow injection chemiluminescence method is proposed for the determination of cobalt, based on the strong catalytic effect
of Cobalt(II) (1,10-phenanthroline)3 complex on the lucigenin-periodate reaction in alkaline medium. Under the optimum experimental conditions, the chemiluminescence
signal responded linearly to the concentration of cobalt(II) in the 1.0 × 10−9–3.0 × 10−7 g mL−1 range with a detection limit of 4.4 × 10−10 g mL−1 cobalt(II). The relative standard deviation for the determination of 5.0 × 10−8 g mL−1 of cobalt was 2.3% in eleven replicated measurements. The method was successfully applied to the determination of cobalt(II)
in pharmaceutical preparations. 相似文献
46.
It was found that the medium affects the rate constant of the thermal decomposition of di(tert-butyl)trioxide. In all solvents studied, the decomposition occurred according to the first-order law. The effect of the solvent on the rate constant was analyzed within the framework of the Koppel-Palm equation.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1167–1168, June, 1995.The authors are grateful to O. N. Makarova for help in this work.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 93-03-5231). 相似文献
47.
S. Kulmala M. HåkanssonA.-M. Spehar A. NymanJ. Kankare K. LoikasT. Ala-Kleme J. Eskola 《Analytica chimica acta》2002,458(2):271-280
Heterogeneous and homogeneous immunoassays of human thyroid stimulating hormone (hTSH) were developed on immunometric basis using aromatic Tb(III) chelates as electrochemiluminescent labels and varied types of disposable oxide-covered aluminum electrodes as the solid phase of the immunoassays. The long luminescence lifetime of the present labels allows the use of time-resolved electrochemiluminescence detection and provide the low detection limits of these labels and, thus, sensitive immunoassays. The primary antibody of immunometric immunoassays was coated upon aluminum oxide surface by physical absorption. In homogeneous immunoassays using 66 μl cell and 15 min incubation time, a linear calibration range of 0.25-324 μU/ml was obtained by applying only a single cathodic excitation pulse in the detection step of the assay. 相似文献
48.
By combining the layer-by-layer (LBL) self-assembly technique with the electrochemical polymerization method, multilayer Ni(II)-polyluminol
films were modified on the surface of a vaseline-impregnated graphite electrode. It was found that, compared with an electrode
modified by direct electrochemical polymerization, this modified electrode offered a suitable ECL reaction micro-environment
created by the special multilayer films, which was beneficial to the ephedrine hydrochloride enhancing effect for luminol
ECL intensity. The ECL enhancing effect of ephedrine hydrochloride on the electro-oxidation luminol was improved on this modified
electrode. Based on this finding, a new sensitive ECL method was developed for ephedrine hydrochloride determination under
the optimal conditions. At the same time, a new idea is proposed for improving the analytical performance of the luminol ECL
system by modifying the ECL reaction micro-environment with the layer-by-layer self- assembly method. Under the optimum experimental
conditions, the ephedrine hydrochloride concentration in the range of 2.0 × 10−8–7.0 × 10−6 mol L−1 was proportional to the enhanced ECL signal, and it offered an 8.0 × 10−9 mol L−1 detection limit for ephedrine hydrochloride. 相似文献
49.
Xi Chen Changqing YiMeijin Li Xin LuZhen Li Peiwei LiXiaoru Wang 《Analytica chimica acta》2002,466(1):79-86
Electrogenerated chemiluminescences (ECLs) based on tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)32+) and lupin alkaloids, for instance, sophoridine (SRI), matrine (MT), sophoranol (SR) and sophocarpine (SC) in an aqueous alkaline buffer solution (pH 9.0) are studied. The light emission is mainly caused by an electro-oxidation reaction between tertiary amino group on the alkaloid compounds and Ru(bpy)32+ in a thin layer flow cell equipped with a glassy carbon disc electrode (22.1 mm2) at the potential of +1.50 V (versus Ag/AgCl). The luminescence wavelength of 610 nm confirmed that ECL is caused by Ru(bpy)32+∗ to its ground state. ECL intensities of these lupin alkaloids are affected by the substituent character, three-dimensional conformation of hydrogen on β-carbon atom. Ionization potentials taken from calculation data further confirm the experimental results. In addition, the factors affecting the determination and HPLC separation of the four alkaloids are also investigated. 相似文献
50.
Shuangqi Pi Quansong Li Ling Yue Prof. Dr. Ya-Jun Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(18):5712-5720
A first-generation pair of chemiluminescent formaldehyde (FA) probes (CFAP540 and CFAP700) was reported recently. CFAP540 and CFAP700, with high selectivity and sensitivity to FA, are, respectively, suitable in cell and in vivo. Experimentalists have confirmed that both probes utilize a general 2-aza-Cope FA-reactive trigger and a chemiluminogenic phenoxydioxetane scaffold. The mechanism and detailed process of CFAP chemiluminescence (CL) remain largely unknown. In the present paper, (time-dependent) density functional theory calculations are performed on the entire reaction process of CFAP540 with FA to produce CL. The calculations elucidated the CL-producing process: FA initiates the decomposition of CFAP540 by dehydration condensation, and a phenoxy 1,2-dioxetane is formed through a series of reactions of aza-Cope rearrangement, hydrolysis of imine, and β-elimination of alkoxyl group. Afterwards, the produced phenoxy 1,2-dioxetane decomposes to produce the m-oxybenzoate derivative in the first singlet state (S1) via two crossings between potential energy surfaces of the ground state (S0) and S1 state. This m-oxybenzoate derivative was assigned as the light emitter of the CFAP540 CL. The CL-producing process and assignment of the light emitter of CFAP700 CL are similar with the corresponding ones of CFAP540. By analyzing the D-π-A architecture of the light emitters of CFAP540 and CFAP700, a series of CFAPs is theoretically designed and a scheme to modulate their CL from visible to near-infrared region is proposed by adjusting the length and structure of the π-bridge. 相似文献