Influence of luminol on the chemiluminescence intensity in Fenton’s reaction

The kinetics of Fe⁺² oxidation and buildup of luminol oxidation products during Fenton’s reaction at pH 2 have been calculated. The characteristics of the process in neutral (pH 6) and alkaline (pH 12) media have been evaluated. The calculation results have been compared with experimental data on the yield of chemiluminescence induced by Fenton’s reagent and luminol. It has been shown that trivalent iron ions suppress the luminol emission. The presence of iron or another transition metal in the sample can significantly reduce the chemiluminescence quantum yield after luminol introduction if.     

Inhibition of superoxide dismutase, Vitamin C and glutathione on chemiluminescence produced by luminol and the mixture of sulfite and bisulfite

In a system which consisted of luminol (3-aminophthalhydrazide), cobalt sulfate (CoSO4), alkaline buffer and the mixture of NaSO3 and sodium bisulfite (NaHSO3) (sulfite and bisulfite=3:1, m/m), a strong chemiluminescence (CL) was observed using a BPCL ultra-weak luminometer. The CL signals resulted from 3-aminophthalate (the product of oxidized luminol), and were affected by the buffer pH, buffer medium and the concentrations of luminol, CoSO4 and the NaSO3-NaHSO3 mixture. The observation that the CL intensities were inhibited by superoxide dismutase (SOD), Vitamin C (Vc) and glutathione (GSH) in a dose-dependent manner suggested that superoxide radical (O2*-) was involved in the CL reaction and responsible for oxidation of luminol.     

Activity of Aliphatic Diperoxy Acids in the Luminol Chemiluminescence Reaction

The activity of dilute aqueous solutions of aliphatic diperoxysuccinic, -glutaric, -adipic, and -sebacic acids in the luminol chemiluminescence reaction is studied. This activity can be detected at a low (10^–6–10^–5M) concentration of luminol in weakly alkaline solutions; it increases as the alkyl chain length of the acid decreases. The best conditions for chemiluminescence have been selected. It has been shown that individual or total diperoxy acids can be determined by luminol chemiluminescence. The determination limit for diperoxyadipic acid used as an example has been estimated at 2.0 ng/mL.     

时间分辨化学发光分析的研究 I: 金和银的同时化学发光测定

本文根据Luminol-K2S2O8体系中Au(III)和Ag(I)化学发光动力学性质的不同, 建立了金和银的时间分辨化学发光分析法, 研究结果表明, 利用时间分辨化学发光分析法同时测定混合物中多组分是可行的.     

Gold Nanoparticles‐enhanced Chemiluminescence Determination of Fenfluramine

A simple and sensitive chemiluminescence method was developed for the determination of fenfluramine. The chemiluminescence signal arising from the reaction between alkaline luminol and N‐bromosuccinimide was found to be greatly enhanced by fenfluramine in the presence of gold nanoparticles. But fenfluramine alone slightly inhibited the CL signal of N‐bromosuccinimide‐luminol in the absence of gold nanoparticles. The experimental parameters that affected the chemiluminescence signal were thoroughly investigated. Under the optimum experimental conditions, the enhanced chemiluminescence intensity was proportional to the concentration of fenfluramine in the range of 0.005‐1.0 mg/L. The detection limit was 0.9 μg/L fenfluramine with a relative standard deviation of 2.5% for 0.1 mg/L fenfluramine solution (n = 11). The method was applied to the determination of fenfluramine in some weight‐reducing tonics and in spiked human urine. A possible CL reaction mechanism was proposed.     

鲁米诺-铁氰化钾化学发光体系对盐酸环丙沙星的测定

环丙沙星对NaOH介质中的鲁米诺-铁氰化钾的化学发光具有较强的增敏作用,据此建立了一种新的测定痕量环丙沙星药物的流动注射化学发光法。讨论了介质浓度、发光试剂浓度等因素的影响,在最佳实验条件下,环丙沙星的质量浓度在2.0×10-5~1.2×10-4g.L-1范围内与发光强度呈良好线性关系,检出限为1.2×10-6g.L-1,11次平行测定4.0×10-5g.L-1环丙沙星的相对标准偏差为3.2%。该方法已用于环丙沙星片剂的测定,所得结果与标示值相符。     

人血多形核白细胞呼吸爆发中活性氧与活性氧模拟酶的关系研究

用多形核白细胞－鲁米诺化学发光法测定具有超氧化物歧化酶（ＳＯＤ）和过氧化氢酶（ＣＡＴ）双功能模拟酶－金属卟啉（四磺酸基苯基铁卟啉、四磺酸基苯基铜卟啉、四磺酸基苯基锰卟啉、四磺酸基苯基钴卟啉）对呼吸爆发所产生的活性氧的影响,结果表明,模拟酶对爆发反应中细胞发光产生抑制,即对活性氧有清除作用;且同一物质随着浓度由１０＾－７－１０＾－５ｍｏｌ／Ｌ,上升而增强。     

Chemiluminescence of luminol catalyzed by silver nanoparticles

Silver nanoparticles (AgNPs) are synthesized by chemical reduction method and characterized by UV-vis spectra, transmission electron microscopy, and high performance particle sizer. We have found that AgNPs could enhance the chemiluminescence (CL) intensity of luminol-H(2)O(2) system. In this reaction, luminol intermediate is generated under alkaline condition on the surface of AgNPs in luminol-H(2)O(2) system and enhances CL intensity. To validate the reaction mechanism, AgNPs are bound with thioglycolic acid (Ag-HSCH(2)COOH) and then joined to BSA protein (Ag-BSA). We investigate the CL intensity in the presence of Ag-HSCH(2)COOH or Ag-BSA comparing with that in the presence of AgNPs and conclude the catalytic reaction take place on the surface of AgNPs.     

高锰酸钾-鲁米诺反应体系中碱土金属离子Mg2+,Ca2+,Sr2+,Ba2+化学发光行为研究

将被认为没有化学发光活性的第二主族(碱土金属)离子Mg^2 ,Ca^2 ,Sr^2 ,Ba^2 溶液注入到已充分反应的高锰酸钾与鲁米诺混合液中时,又发生了新的化学发光反应,并检测到强的化学发光信号．在对有关反应的动力学性质、化学发光光谱、紫外可见光谱及其它一系列实验研究的基础上,提出了可能的化学发光反应机理．同时,优化了反应条件,评价了这一反应用于Mg^2 ,Ca^2 ,Sr^2 ,Ba^2 分析的可行性．     

Electrogenerated chemiluminescence of luminol on a gold-nanorod-modified gold electrode

Electrogenerated chemiluminescence (ECL) of luminol on a gold-nanorod-modified gold electrode was studied, and five ECL peaks were obtained under conventional cyclic voltammetry in both neutral and alkaline solutions. Among them, four ECL peaks (ECL-1-4) were also observed on a gold-nanosphere-modified gold electrode, but the intensities of these ECL peaks were enhanced about 2-10-fold on a gold-nanorod-modified gold electrode in neutral solution. One new strong ECL peak (ECL-5) was obtained at -0.28 V (vs SCE) on a gold-nanorod-modified gold electrode in both neutral and alkaline solutions and enhanced with an increase in pH. In strong alkaline solutions, ECL-1 and ECL-2 on a gold-nanosphere-modified electrode were much stronger than those on a gold-nanorod-modified gold electrode, while ECL-3-5 appeared to only happen on a gold-nanorod-modified gold electrode. The emitter of all the ECL peaks was identified as 3-aminophthalate. The ECL peaks were found to depend on the scan direction, the electrolytes, the pH, and the presence of O(2) and N(2). The reaction pathways for ECL-4 have been further elucidated, and the mechanism of the new ECL peak (ECL-5) has been proposed. The results indicate that a gold-nanorod-modified gold electrode has a catalytic effect on luminol ECL different from that of a gold-nanosphere-modified gold electrode, revealing that the shape of the metal nanoparticles has an important effect on the luminol ECL behavior. The strong ECL of luminol in neutral solution obtained on a gold-nanorod-modified electrode may be used for the sensitive detection of biologically important compounds in physiological conditions.     

Direct determination of horseradish peroxidase encapsulated in liposomes by using luminol chemiluminescence.

Horseradish peroxidase (HRP) encapsulated in liposomes was directly detected by using luminol chemiluminescence (CL) with H2O2 without lysis of liposomes. At a low concentration of H2O2, the initial rate of HRP-catalyzed luminol CL in liposomes was slower than that of HRP-catalyzed luminol CL in a lipid-free bulk solution. The decrease in the initial rate of the CL reaction in liposomes was due to the membrane permeation of luminol and H2O2. At a high concentration of H2O2, the initial rate of the CL reaction in liposomes was the same as that in a lipid-free bulk solution. The CL measurement conditions in both a lipid-free bulk solution and in liposomes were optimized in the concentrations of luminol and H2O2 by measuring the CL response curves, in which only one peak appeared and the CL intensity was maximal. The CL intensity observed in HRP-catalyzed luminol CL in liposomes was a factor of seven greater than that observed in a lipid-free bulk solution. The CL intensity was dependent on the amount of HRP-encapsulated liposomes used. The detection limit in the direct detection of HRP encapsulated in liposomes was sensitive by a factor of 3 compared with that in HRP-catalyzed luminol CL in a lipid-free bulk solution.     

流动注射化学发光法测定头孢噻肟钠

基于在碱性介质中头孢噻肟钠对鲁米诺-K3Fe(CN)6化学发光体系的增强作用,建立了流动注射化学发光测定头孢噻肟钠的新方法.头孢噻肟钠的质量浓度与化学发光强度的变化在2.4～30 mg/L和60～300 mg/L范围内呈良好的线性关系,检出限为0.63 mg/L,对浓度为30 mg/L的头孢噻肟钠进行9次平行测定,相对标准偏差(RSD)为1.0%.该法简便、快速、可靠,将其用于头孢噻肟钠针剂的测定,结果令人满意.     

Flow-injection chemiluminescence determination of chlorinated isocyanuric acids

A rapid and sensitive flow-injection chemiluminescence method is described for the determination of dichloro- and trichloroisocyanuric acids based on the chemiluminescence produced during their reaction with luminol in alkaline medium. The effects of analytical and flow-injection variables on these chemiluminescence systems and determination of both oxidants are discussed. The optimized method yielded 3sigma detection limits of 8x10(-8) and 5x10(-8) mol L(-1) for the sodium dichloroisocyanurate and trichloroisocyanuric acid, respectively. The optimum conditions were found to be as follows: NaOH, 1x10(-1) mol L(-1); luminol, 5x10(-3) mol L(-1); KI, 2x10(-3) mol L(-1) and flow rate, 3.5 mL min(-1).     

Determined GA by FI‐CE in Luminol‐H2O2 System

It was found that the chemiluminescence arising from the reaction of luminol with H₂O₂ involving Co(II)‐catalyzed in alkaline solution could be strongly inhibited by gibberellic acid. Based on this observation, a new flow injection chemiluminescence method is proposed for the determination of gibberellic acid. The detection limits of the method are 0.09 ng mL^?1 gibberellic acid. The method was successfully applied to the determination of gibberellic acid in bacteria‐free culture liquid.     

Loading effects of silver oxides upon generation of reactive oxygen species in semiconductor photocatalysis

Superoxide anion radical (O(2)(-*)) and OH radical generations in suspensions of Ag metal-, Ag(2)O-, or AgO-loaded TiO(2) and BiVO(4) photocatalysts in alkaline conditions (pH 12.0) were examined by means of a luminol chemiluminescence (CL) technique and a spin-trapping fluorescence one in which terephthalic acid reacts with an OH radical to afford the highly fluorescent 2-hydroxyterephthalic acid (TAOH), respectively. The observed luminol CL intensity was remarkably enhanced by the AgO loading on TiO(2) as well as BiVO(4). This can be explained by enhancement of O(2)(-*) production on the AgO-loaded photocatalysts caused by the synergetic effects on the thermocatalytic activity upon the AgO surface and the efficient electron-hole separation at the photocatalyst/AgO interface. On the other hand, loading effects of AgO on the TAOH formation were not so significant compared to those on the CL observation, though the TAOH formation rates for the TiO(2) samples were much larger than those for the BiVO(4) ones by about three orders of magnitude. The properties of O(2)(-*) and OH radical generations on these photocatalysts are discussed on the basis of the luminol CL kinetics and approximate band edge positions of TiO(2), BiVO(4), and silver oxides.     

基于CoFe(Ⅲ)PBA/GO过氧化物模拟酶化学发光法检测H2O2和抗坏血酸

制备了一种具有过氧化物酶活性的类普鲁士蓝/氧化石墨烯复合纳米材料(CoFe(Ⅲ)PBA/GO)。将具有过氧化物酶活性的CoFe(Ⅲ)PBA/GO和化学发光法相结合,构建了一种用于检测H₂O₂和抗坏血酸(AA)的化学发光分析法。CoFe(Ⅲ)PBA/GO催化H₂O₂产生的O₂·^-,·OH,1O₂自由基氧化Luminol会产生很强的化学发光信号,通过检测化学发光强度可以实现对H₂O₂的检测。该方法检测H₂O₂的线性范围为0~0.8μmol/L,检测限为11 nmol/L。利用AA作为活性氧消除剂可以抑制化学发光反应的特点,实现了AA的检测。该方法测定AA的线性范围为0.02~0.8μmol/L,检测限为20 nmol/L。方法已应用于H₂O₂消毒水中H₂O₂和维生素C片中抗坏血酸的检测。     

Chemiluminescence assay for uric acid in human serum and urine using flow-injection with immobilized reagents technology

A novel chemiluminescence (CL) flow sensor for the determination of uric acid in human urine and serum has been developed by using controlled-reagent-release technology. The reagents involved in the chemiluminescence (CL) reaction, luminol and periodate, are immobilized on anion-exchange resin packed in a column. After injection of water, chemiluminescence generated by released luminol and periodate in alkaline media is inhibited in presence of uric acid. By measuring the decreased chemiluminescence (CL) intensity the uric acid is sensed. The decreased response is linear in the 5.0-500.0 ng mL(-1) range, with a detection limit of 1.8 ng mL(-1). The flow sensor showed remarkable operational stability and could be easily reused for over 80 h with sampling frequency of 100 h(-1). The proposed sensor was applied to the determination of uric acid in human urine and serum, and monitoring metabolic uric acid in human urine with RSD less than 3.0%.     

毛细管电泳免疫化学发光高灵敏检测人血清中肿瘤标志物甲胎蛋白

本文首次报道了人血清免疫反应后直接进样并利用毛细管电泳分离化学发光灵敏检测AFP的新方法, 检测结果与医院使用的全自动微粒子化学发光仪检测结果吻合.     

The inhibition by amines and amino acids of bleach-induced luminol chemiluminescence during forensic screening for blood

Sprays containing alkaline solutions of peroxide and luminol are used as presumptive screens for bloodstains at crime scenes. These sprays can be subject to interference from hypochlorite-based cleaning agents (bleaches), leading to false positive results. This paper reports the screening of amines for their ability to decrease the interference by bleach while not greatly affecting the reaction with blood. The addition of glycine (0.05 mol L⁻¹) to the Grodsky formulation of luminol spray, together with an adjustment of the pH to 12, gave good discrimination between blood and bleach, and has the advantage that glycine is non-toxic compared to many other amines. The modified spray gave similar chemiluminescence intensity and duration as the unmodified Grodsky spray. However, it is recommended that this modification only be used when there is evidence that hypochlorite bleach may have been used at a scene. The amines triethylamine and sulfamate led to enhanced chemiluminescence in the presence of hypochlorite.     

THE REACTIVITY OF SUPEROXIDE (O2-) and ITS ABILITY TO INDUCE CHEMILUMINESCENCE WITH LUMINOL

Abstract— The quantum yield and the kinetics of O -induced luminol chemiluminescence was investigated in a broad pH interval at varying luminol and concentrations. It is suggested that the weak chemiluminescence observed is mediated via a luminol-superoxide-adduct proposed to be an a-hydroxyperoxyl radical. At pH 7 the maximum quantum yield of chemiluminescence per initial percent was determined to be 4 times 10^-8. The degree of involvement in phagocytosis and related processes should be viewed against this maximum limit.