A review of recent advances in chemiluminescence detection using nano-colloidal manganese(IV)

A chemiluminescence reaction consisting of manganese(IV), sodium sulfite, and sulfur- and nitrogen-doped carbon quantum dots, and its application for the determination of oxytetracycline

Sulfur- and nitrogen-doped carbon quantum dots (S,N-CQDs) were prepared by a solid-phase hydrothermal method from cysteine and citric acid and characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and FTIR spectroscopy. These QDs were exploited as enhancers to amplify the chemiluminescence (CL) of manganese(IV)-sodium sulfite reaction. S,N-CQDs exceptionally enhanced the CL intensity of this system, around 900-fold. This effect was attributed to the energy transfer from SO₂^*, produced by reaction of Mn(IV) with SO₃^2-, to S,N-CQDs. The maximum wavelength of CL emission was 480 nm, which confirmed that the final emitting species was S,N-CQDs. After optimization of reaction conditions, the analytical applicability of S,N-CQD-Mn(IV)-SO₃^2- CL system was studied. In the presence of oxytetracycline, the CL intensity was significantly diminished. A linear relationship was observed between CL signal and the logarithm of oxytetracycline concentration in the range of 0.075-3.0 μM with a detection limit of 25 nM. This CL assay for oxytetracycline was used for analysis of spiked milk and water samples. Graphical abstractSchematic representation of the amplified chemiluminescence (CL) reaction consisting of sulfur- and nitrogen-doped carbon quantum dots (S,N-CQDs) Mn(IV) and Na2SO3. Sub-micromolar levels of oxytetracycline can be determined by using this system.

A highly selective chemiluminescent probe for the detection of chromium(VI)

In present work, rhodamine B hydrazide and rhodamine 6G hydrazide were synthesized and the chemiluminescence performance has been investigated. Based on the chemiluminescence of rhodamine 6G hydrazide‑chromium(VI), a selective and sensitive method for the direct detection of chromium(VI) was developed. The chemiluminescence intensity was linearly related to the concentration of chromium(VI) in the range of 2.60×10^-8-8.00×10^-6mol/L with a correlation coefficient of r=0.998 and a detection limit of 1.4×10^-8mol/L (S/N=3). The results indicated rhodamine 6G hydrazide was an excellent chemiluminescent probe for chromium(VI) without reduction of chromium(VI) to chromium(III). A possible mechanism of CL emission was also suggested.

Flow analysis with chemiluminescence detection: Recent advances and applications

This article highlights the most important developments in flow analysis with chemiluminescence (CL) detection, describing different flow systems that are compatible with CL detection, detector designs, commonly applied CL reactions and approaches to sample treatment. Recent applications of flow analysis with CL detection (focusing on outputs published since 2010) are also presented. Applications are classified by sample matrix, covering foods and beverages, environmental matrices, pharmaceuticals and biological fluids. Comprehensive tables are provided for each area, listing the specific sample matrix, CL reaction used, linear range, limit of detection and sample treatment for each analyte. Finally, recent and emerging trends in the field are also discussed.

Ultra-high Performance Liquid Chromatography with Photodiode Array and Chemiluminescence Detection for the Determination of Polyphenolic Antioxidants in Erigeron acris L. Extracts

INTRODUCTION

The quality of herbs is directly related to the presence of polyphenolic antioxidants. This is the first report on the quantification of individual polyphenolic constituents of Erigeron acris L.

OBJECTIVE

To develop a new method using ultra-high performance liquid chromatography with photodiode array and chemiluminescence (UHPLC-PDA-CL) detection for the separation and determination of polyphenols in Erigeron acris extracts.

METHODOLOGY

The methanolic extracts from leaves and inflorescences of Erigeron acris were prepared by ultrasound assisted extraction. The chromatographic separation was performed on C18 column packed with 1.7-μm particles. The post-column CL detection was based on the enhancing effect of polyphenols on the CL generated in manganese(IV)-hexametaphosphate-formaldehyde system.

RESULTS

The UHPLC method allowed to separate polyphenols in a short running time (13 min), which was three times shorter compared with traditional HPLC. The CL detection was characterised by 6-48 times higher sensitivity and up to three times lower detection limits compared to PDA detection. Qualitative and quantitative differences were observed in polyphenolic composition of Erigeron acris extracts. The main components of leaves were scutellarin and chlorogenic acid, whereas in inflorescences quercetin 3-O-glucoside was predominant.

CONCLUSION

Coupling of UHPLC with CL detection has been developed for the first time. This advanced chromatographic technique coupled with sensitive CL detection is a powerful approach for the investigation of polyphenolic profiles in natural products. The shorter analysis time and diminished waste generation makes the UHPLC method more environmentally friendly and more cost-effective in comparison with conventional HPLC. Copyright © 2016 John Wiley & Sons, Ltd.

A study on the selection of chemiluminescence system for the flow injection determination of the total polyphenol index of plant-derived foods

Different chemiluminescence systems based on luminol, permanganate, manganese(IV) and cerium(IV) reagents were compared regarding their sensitivity and selectivity to determine plant polyphenols. Among the seventeen systems tested, Mn(IV)-formaldehyde-hexametaphosphate was considered to be the most suitable for polyphenols detection. The developed flow injection method (FI-CL) based on enhancing effect of polyphenols on Mn(IV) chemiluminescence is characterised by low detection limit of gallic acid (0.02μgL(-1)) and high precision (RSD=1.7%). The calibration graph was linear from 0.1 to 100μgL(-1). The selectivity studies revealed that the FI-CL method ensures accurate determination of the total polyphenols content in food samples. The method was successfully applied to analysis of a variety of plant-derived foods (wine, tea, cereal coffee, fruit and vegetable juices, herbs and spices). The proposed method is superior to conventional spectrophotometric assays due to its higher sample throughput (195samplesh(-1)), simplicity, sensitivity and, above all, higher selectivity.