Determination of alizarin red S based on layered double hydroxides-improved chemiluminescence from hydrogen peroxide and luminol

Abstract

In this report, a simple chemiluminescence (CL) approach for detecting an anionic dye, alizarin red S (ARS), based on layered double hydroxides (LDHs)-improved CL from hydrogen peroxide (H₂O₂) and luminol system is proposed. The LDHs-improved H₂O₂–luminol CL is due to the adsorption of luminol dianion and peroxide anion onto the positively charged brucite-like layers and the facilitated formation of carbonate radicals, which benefits the generation of light-emitting intermediate 3-aminophthalate anions. Notably, the LDHs-improved H₂O₂–luminol CL signal is markedly restrained in the presence of ARS, which is assigned to the ARS-mediated occupation of the positively charged centres on the brucite-like layers and the inhibition of the formation of 3-aminophthalate anions. Thus, a facile CL method for ARS perception based on the suppression effect of ARS toward the LDHs-improved H₂O₂–luminol CL has been developed. This simple CL approach shows a limit of detection of 0.1 μM toward ARS and exhibits a linear response in the concentration range from 0.5 to 30 μM. In addition, the proposed method exhibits a high specificity toward ARS over other small molecules, metal ions or anions. Furthermore, the practical application of the proposed method for ARS sensing is evaluated with the dye wastewater samples.