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A new chemiluminescent (CL) probe array assay approach was first developed. The new CL probe array was based on Co3O4-SiO2 mesoporous nanocomposite material, which not only has an excellent catalytic effect on the luminol-H2O2 CL reaction in alkaline medium but also can be used for the immobilization of enzymes. As a model, the novel bifunctional CL probe array has been applied to the high-throughput determination of glucose in human. The linear range of the glucose concentration was 3-90 μM and the detection limit was 0.36 μM. It breaks traditional development view in solid phase supports and provides new insights into the application of mesoporous material., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this work, cerium oxide nanoparticles are capable of strongly enhancing the chemiluminescence (CL) of the luminol-hydrogen peroxide (H2O2) system. Based on this, a microarray CL method for the determination of the removal rate constant of H2O2 by human erythrocytes has been developed. It is providing direct evidence for a H2O2-removing enzyme in human erythrocytes that acts as the predominant catalyst. A reaction mechanism is discussed. The proposed microarray CL method is sensitive, selective, simple and time-saving, and has good reproducibility and high throughput. Relative CL intensity is linearly related to the concentration of H2O2 in the range from 0.01 to 50 μM. The limit of detection is as low as 6.5 × 10(-11) M (3σ), and the relative standard deviation is 2. 1 % at 1 μM levels of H2O2 (for n = 11).

The catalytic properties of cubiform Co3O4 nanoparticles, α-Fe2O3 nanorods, and NiO nanoparticles were studied using both microarray method and FI-CL method. These nanoarticles exhibit high specific catalytic effects on the chemiluminescence (CL) reaction of the luminol-H2O2 system in alkaline solution compared with other common catalysts. A reaction mechanism is described. It provides new insights into the application of nanoparticle materials. The CL method based on the use of the Co3O4 nanoparticles is ultrasensitive and particularly selective. Therefore, it was applied to the analysis of H2O2 which can be determined in the concentration range from 1.0 nM to 1000 nM, with a detection limit of 0.3 nM. The relative standard deviation is 2.1% at 0.1 μM of H2O2 (for n=11). The method was successfully applied to the determination of trace quantities of H2O2 in exhaled breath condensate (EBC) where it is a mediator of oxidative stress and a promising biomarker for diagnosing. The assay requires a small sample and no incubation time, and has an analytical runtime of <1 min. It is timesaving and suitable for larger studies. The levels of H2O2 in EBC are found to be elevated in healthy subjects (average=0.54 nM), rheum subjects (average=0.24 nM), and feverish subjects (average=0.16 nM). Our data suggested that the average H2O2 concentration of EBC from feverish subjects was significantly higher than healthy subjects and rheumatic subjects., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this paper, a novel flow injection chemiluminescence (FI-CL) method is proposed for the determination of picomolar L(-1) levels of hydrogen peroxide (H(2)O(2)) in exhaled breath condensate (EBC). This method is based on the oxidation of a low concentration of luminol (10(-7) M) by H(2)O(2) at a low concentration level (< 10(-8) M) in an alkaline medium catalyzed by a complex, K(5)[Cu(HIO(6))(2)] (DPC), which is not interfered by other metal ions or horseradish peroxidase (HRP). Under the optimum conditions, H(2)O(2) was determined over the range of 1.0 x 10(-10) to 1.0 x 10(-8) mol L(-1) with a detection limit of (3sigma) of 4.1 x 10(-11) mol L(-1). The relative standard deviation (RSD) was 3.2% for 5 nmol L(-1) H(2)O(2) (n = 7). The proposed method offers the advantages of ultra-sensitivity, selectivity, simplicity and rapidity for H(2)O(2) determination. It was successfully applied to directly determine trace amounts of H(2)O(2) (nmol L(-1)) in human's EBC of both rheum and healthy volunteers. A statistically significant difference was found between patients with rheum (n = 11) and control subjects without rheum (n = 11).

Monitoring hydrogen peroxide (H(2)O(2)) in aqueous cigarette smoke condensate (CSC) is helpful for interpreting the relationship between cigarette smoke and oxidative stress, inflammation and disease. It is also significative for elucidating the pathogenic effects of CSC. In this paper, a novel flow-injection chemiluminescence (FI-CL) method was well established for determination of H(2)O(2) in the complex sample CSC which did not need pretreatment. The sensitive and selective method is based on the CL reaction of luminol with low concentration (10(-7) molL(-1)) and H(2)O(2) at low concentration level (<10(-8) molL(-1)) in an alkaline medium catalyzed by a complex K(5)[Cu(HIO(6))(2)] (DPC), which has proved no interference of other metal ions or horseradish peroxidase (HRP). The proposed method had been used to determine trace amount of H(2)O(2) with a limit of detection (3sigma) of 4.1 x 10(-11) molL(-1), which enables minimal amount of sample for analysis. A satisfactory result has been gained for the determination of H(2)O(2) in CSC sample by use of the proposed method. The concentration of H(2)O(2) in two reference cigarette (84 cm, Longfeng) smoke condensate have been determined at 4-6 micromolL(-1) level.

A highly sensitive flow-injection chemiluminescence (FI-CL) method has been developed for the determination of dihydroxybenzene, based on the hydroxyl radical reaction. Hydroxyl radical (.OH) produced by the reaction of Fe(3+) and H(2)O(2) oxidize rhodamine 6G to produce weak CL. It was observed that catechol and hydroquinone greatly enhanced the weak CL reaction. However, the proposed CL system is not suitable for determination of resorcinol because the enhancement reaction is very slow. The proposed procedure has a linear range of 0.01-2 mg/L for catechol, with a detection limit of 0.006 mg/L, and 0.008-1 mg/L for hydroquinone, with a detection limit of 0.004 mg/L. The possible mechanism of the CL system is discussed.

In the absence of any special luminescence reagent, emission of weak chemiluminescence has been observed during the decomposition of hydrogen peroxide catalyzed by copper(II) in basic aqueous solution. The intensity of the chemiluminescence was greatly enhanced by addition of DNA and was strongly dependent on DNA concentration. Based on these phenomena, a flow-injection chemiluminescence method was established for determination of DNA. The chemiluminescence intensity was linear with DNA concentration in the range 2 x 10(-7)-1 x 10(-5) g L(-1) and the detection limit was 4.1 x 10(-8) g L(-1) (S/N=3). The relative standard deviation was less than 3.0% for 4 x 10(-7) g L(-1) DNA (n=11). The proposed method was satisfactorily applied for determination of DNA in synthetic samples. The possible mechanism of the CL reaction is discussed.

Chromium oxide (Cr2O3) nanoparticles were found to greatly enhance the chemiluminescence (CL) of the luminol–hydrogen peroxide (H2O2) system. A novel microarray CL method was originally developed for the detection of triacetone triperoxide (TATP). The novel CL method was based on the outstanding catalytic effect of a Cr2O3 nanoparticle array on the CL reaction between lower concentrations of luminol and H2O2, which come from hydrolysis of TATP vapor. The calibration curve of H2O2 was linear over a range of 1.0 × 10−8 to 3.0 × 10−5 M with a detection limit of 1.6 × 10−9 M (R2 = 0.9992, n = 12). The CL method has the advantages of being sensitive, selective, simple, time-saving, high-throughput, and shows good reproducibility. Therefore, these merits would make it easily popular. [ABSTRACT FROM AUTHOR]

A novel chemiluminescence (CL) method for the determination of hydrogen peroxide is described. Method is based on the transition metals in highest oxidation state complex, which include diperiodatoargentate (DPA) and diperiodatonickelate (DPN) and show excellent sensitisation on the luminol-H2O2 CL reaction with low luminol concentration in alkaline medium. In particular, the sensitiser which was previously reported (such as Co2+, Cu2+, Ni2+, Mn2+, Fe3+, Cr3+, KIO4, K3Fe(CN)6 etc.) to be unobserved CL due to poor sensitisation with such low concentration of luminol which makes the method hold high selectivity. Based on this observation, the detection limits were 6.5 × 10−9 mol L−1 and 1.1 × 10−8 mol L−1 hydrogen peroxide for the DPN- and DPA-luminol CL systems, respectively. The relative CL intensity was linear with the hydrogen peroxide concentration in the range of 2.0 × 10−8–6.0 × 10−6 mol L−1 and 4.0 × 10−8–4.0 × 10−6 mol L−1 for the DPN- and DPA-luminol CL systems, respectively. The proposed method had good reproducibility with a relative standard deviation of 3.4% (8.0 × 10−7 mol L−1, n = 7) and 1.0% (2.0 × 10−6 mol L−1, n = 7) for the DPN- and DPA-luminol CL systems, respectively. A satisfactory result has been gained for the determination of H2O2 in rainwater and artificial lake water by use of the proposed method. [ABSTRACT FROM AUTHOR]

n enzyme-linked immunosorbent assay, a horseradish peroxidase-catalyzed fluorogenic reaction, and chemiluminescence (CL) analysis have been combined to develop a sandwich ELISA for Staphylococcal enterotoxin B (SEB) using monoclonal antibodies for different epitopes of SEB. The enzyme catalyzed reaction of 3-(4-hydroxyphenyl propionate) with the urea complex of hydrogen peroxide produced a fluorescent dimer which was detected by chemiluminescence analysis. The CL response to SEB is linear in the range from 6.0 to 564 pg mL ( r = 0.9993), and the detection limit is 3.3 pg mL (S/N = 3). Intra- and interassay coefficients of variation are <7.0% at three concentrations (24, 96 and 384 pg mL). The method was applied to the analysis of SEB in serum, lake water and milk samples. The results compared well with those obtained by conventional ELISAs. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: Measurement methods for ultrasonic fields are important for reasons of safety. The investigation of an ultrasonic field can be performed by detecting the yield of hydroxyl radicals resulting from ultrasonic cavitations. In this paper, a novel method is introduced for detecting hydroxyl radicals by a chemiluminescence (CL) reaction of luminol-hydrogen peroxide (H2O2)–K5[Cu(HIO6)2](DPC). The yield of hydroxyl radicals is calculated directly by the relative CL intensity according to the corresponding concentration of H2O2. This proposed CL method makes it possible to perform an in-line and real-time assay of hydroxyl radicals in an ultrasonic aqueous solution. With flow injection (FI) technology, this novel CL reaction is sensitive enough to detect ultra trace amounts of H2O2 with a limit of detection (3σ) of 4.1×10−11 molL−1. The influences of ultrasonic output power and ultrasonic treatment time on the yield of hydroxyl radicals by an ultrasound generator were also studied. The results indicate that the amount of hydroxyl radicals increases with the increase of ultrasonic output power (⩽15WmL−1). There is a linear relationship between the time of ultrasonic treatment and the yield of H2O2. The ultrasonic field of an ultrasonic cleaning baths has been measured by calculating the yield of hydroxyl radicals. [Copyright &y& Elsevier]