Cationic liposome-triggered luminol chemiluminescence reaction and its applications

Bimetallic CuFe Prussian blue analogue cubes enhanced luminol chemiluminesence and its application

In this paper, bimetallic CuFe Prussian blue analogue (CuFe PBA) was discovered to have oxidase-like activity. Luminol can be oxidized under alkaline conditions without adding other oxidants. The chemiluminescence (CL) intensity produced is more than 1000 times that of the original luminol-NaOH system. Thus, a novel luminol-NaOH-CuFe PBA CL sensor was constructed. The CL intensity of the system would drastically decrease with the addition of uric acid (UA), it served as the foundation for the creation of an enzyme-free CL sensor for the determination of UA. The CL signal intensity of the system showed a linear connection with the square of the UA concentration in the range of 0.25 to 0.45 mmol·L-1, and the limits of detection was 0.10 mmol·L-1. This system could be used to construct an efficient CL sensor for the detection of UA in human serum.

Enhancement effect of 2, 3-dimethyl maleic acid on luminol chemiluminescence reactions and its application in detection of sequence-specific DNA related to hepatitis B virus

2, 3-dimethyl maleic acid (DMMA) was found to enhance luminol-H₂O₂ chemiluminescent (CL) reactions, among which the strongest enhancement effect was observed by using polyethyleneimine-templated gold nanoclusters (PEI-Au NCs) as the catalyst. With the addition of DMMA, the CL signal of the PEI-Au NCs-catalyzed luminol-H₂O₂ reaction enhanced about 630-fold, and a flash-type CL profile was obtained. Mechanism studies showed that the luminophore was still 3-aminophthalate anions in the excited state (3-APA*), and superoxide radical (O₂^·-) played an important role during the CL process. Under the optimized experimental conditions, the lowest concentration of PEI-Au NCs can be detected was 0.168 nM which was 82-fold lower than that without an enhancer. Furthermore, the catalytic activity of biotinylated PEI-Au NCs in the DMMA-enhanced luminol system was similar to PEI-Au NCs, providing a good opportunity for the development of CL bioanalysis platforms using PEI-Au NCs as the label. Thus, the DMMA-enhanced luminol-H₂O₂ system was applied to the CL detection of sequence-specific DNA related to the hepatitis B virus (HBV) using PEI-Au NCs as the label. The CL platform exhibited linearly enhanced CL response with the increasing amount of target DNA ranging from 0.0025 to 0.5 pmol. As low as 0.002 pmol of HBV DNA could be sensitively detected, which was superior to the previously reported methods.

Natural catalyst for Luminol chemiluminesence - Application to validate peroxide levels in commercial hair dyes

Herein, we report hydrothermally treated green leaves (Moringa Oleifera) extract exploited as an efficient and highly-sensitive catalyst to catalyse the Chemiluminescence (CL) reaction of luminol. In the absence of enhancer, this green and hydrothermally treated catalyst (GHT) was found to significantly enhance the CL intensity about 3.5 fold as compared to the traditionally used K₃ Fe(CN)₆ catalyst. The structure and surface morphology of the catalyst was elucidated by XPS, SEM, XRD and Raman spectroscopy. The synergistic effect of the catalyst in the CL reaction was systematically investigated in the presence of hydrogen peroxide using UV Visible and chemiluminesence spectroscopy. Studies show that the sensitivity of the catalyst could be amplified by adjusting several parameters such as pH of the medium, concentrations of the base and luminol. The sensitivity of the novel-type catalyst was examined through the validation of hydrogen peroxide levels in the commercial hair dye samples. Remarkably, the catalyst displayed ultra-sensitivity to hydrogen peroxide as the limit of detection (LOD) of H₂ O₂ using this catalyst is determined to be 0.02 μM under optimized conditions. In general, the proposed inexpensive, eco-friendly, and non-toxic catalyst could enable the determination of the hydrogen peroxide for diverse analytical applications.

A novel metal organic gel with superior oxidase-like activity for efficient and sensitive chemiluminescence detection of uric acid

It is found that MIL-100(Fe) gels, as a kind of metal-organic gels (MOGs), constitutting of iron (Fe³⁺) and trimesic acid (H₃BTC), has been regarded as the efficient catalyst of luminol chemiluminescence (CL) system without the presence of extra oxidants in the present work. MIL-100(Fe) gels that have possessed mimicking oxidase-like activity can excellently enhanced luminol CL intensity by accelerating the generation of reactive oxygen species. Furthermore, with the addition of uric acid (UA), the CL signal has been dramatically inhibited under alkaline condition. Hence, the CL intensity inhibiting ratio (I₀/I_S) was proportional to the increasing concentration of UA in the rang from 10 nM to 4000 nM with the detection limit of 5.9 nM. This method has been successfully applied for analysis of UA with acceptable recoveries ranging from 97.0% to 107.9% in urine sample. These results indicates that this study open up a novel, sensitive and convenient method to detect UA in biological samples.

Nanomaterial-enhanced chemiluminescence reactions and their applications

Chemiluminescence (CL) analysis is a trace analytical method that possesses advantages including high sensitivity, wide linear range, easy operation, and simple instruments. With the development of nanotechnology, many nanomaterial (NM)-enhanced CL systems have been established in recent years and applied for the CL detection of metal ions, anions, small molecules, tumor markers, sequence-specific DNA, and RNA. This review summarizes the research progress of the nanomaterial-enhanced CL systems the past five years. These CL reactions include luminol, peroxyoxalate, lucigenin, ultraweak CL reactions, and so on. The CL mechanisms of the nanomaterial-enhanced CL systems are discussed in the first section. Nanomaterials take part in the CL reactions as the catalyst, CL emitter, energy acceptor, and reductant. Their applications are summarized in the second section. Finally, the challenges and opportunities are discussed.