Sensitive and Selective Carmine Acid Detection Based on Chemiluminescence Quenching of Layer Doubled Hydroxide-Luminol-H2O2 System.

Feng Pan,Chao Lu,Yilin Zhang,Zhiqin Yuan

doi:10.1021/acsomega.8b02342

Feng Pan, Chao Lu + Show 2 more

Open Access

https://doi.org/10.1021/acsomega.8b02342

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Abstract

Carminic acid (CA) extracted from cochineal is widely used in food additives as a natural colorant, and its potential risk to human health makes its detection important. In this work, a layered doubled hydroxide (LDH)–luminol–H2O2 system-based chemiluminescence (CL) platform has been successfully applied for CA sensing. The principle detection consists of two steps: first, LDH adsorbs CA onto the surface via electrostatic attraction; second, CA quenches the CL of the LDH–luminol–H2O2 system via the synergistic effect of CL resonance energy transfer, reduction of reactive oxygen species, and occupation of positively charged centers of brucite-like layers. With this CL approach, 0.5 μM CA is detectable using a CL spectrometer, and the limit of detection is 0.03 μM. This CL system exhibited a linear response to CA in the concentration range from 0.5 to 10 μM. In addition, the practical application of the designed CL sensing system is evaluated with dried pork slice samples.

Highlights

Carminic acid (CA), an anthraquinone glycoside from dried cochineal with high solubility due to its sugar and carboxyl group residues, has been widely used as red colorant in food or beverage to make them colorful and influence the consumer’s choice.[1]
The layered doubled hydroxide (LDH)-enhanced CL is attributed to the LDH-promoted adsorption of the peroxide anion and luminol dianion, which facilitates the formation of carbonate radicals and luminol radicals and is demonstrated in previous reports.[23]
We have reported a facile CL platform to detect carmine acid based on the LDH−luminol−H2O2 system

Summary

■ INTRODUCTION

Carminic acid (CA), an anthraquinone glycoside from dried cochineal with high solubility due to its sugar and carboxyl group residues, has been widely used as red colorant in food or beverage to make them colorful and influence the consumer’s choice.[1]. 1,2-DHAQ and ACGF, with similar absorption profiles, showed totally different CL quenching capabilities, further suggesting the importance of the structural motif to the CL quenching performance. The trends of the substituent hydroxyl group-promoted CL quenching efficiency in the LDH−H2O2−lucigenin system and the LDH−H2O2−NaIO4 system were consistent with that in the LDH−H2O2−luminol system All these results suggest that 1,2,4-THAQ motif is responsible for the high CL quenching efficiency of CA. The zeta potential of LDH dramatically decreased after adding hydroxyanthraquinone compounds, indicating that the occupation of positively charged centers of brucite-like layers is important to CL quenching. Sensitivity and Selectivity of CA Sensing System These hydroxyanthraquinone compounds showed different CL quenching capabilities, interestingly, they did not cause any evident change in the CL emission profile. From 1 to 16: sodium benzoate (100 μM), citric acid (100 μM), glucose (100 μM), sucrose (100 μM), HPO42− (150 μM), SO42− (150 μM), Mg2+ (500 μM), Al3+ (500 μM), Ba2+ (500 μM), Ca2+ (500 μM), Zn2+ (500μM), K+ (800 μM), Na+ (800 μM), Cl− (800 μM), NH4+ (800 μM), and NO3− (800 μM), respectively

■ CONCLUSIONS

■ ACKNOWLEDGMENTS

■ REFERENCES