Fabrication of a fluorescence/colorimetric multi-channel sensor array utilizing riboflavin derived bimetallic-doped Ce-MOF based peroxidase mimic for highly efficient determination of heavy metal ions.

Current heavy metal contamination poses significant risks to Chinese herbal medicine during both cultivation and consumption stages, underscoring the necessity for rigorous monitoring of diverse heavy metals to ensure quality control. In this study, a biocompatible ligand, riboflavin (vitamin B2), was employed in conjunction with transition metals Cu, Ce, and Fe to synthesize a novel Cu,Fe@Ce-MOF(VB2) composite. This material demonstrates distinctive peroxidase (POD)-like catalytic activity alongside inherent fluorescence properties, facilitating the oxidation of three chromogenic substrates-TMB, ABTS, and DAB-resulting in multicolor chromogenic responses. Additionally, its fluorescence emission is modulated by the presence of various target metal ions. These features enable the simultaneous identification and detection of ten heavy metal ions at concentrations as low as 16.67 μg/mL, as well as the discrimination of ternary mixtures of metal ions. The findings present a rapid, intuitive, and efficient approach for the detection and differentiation of multiple heavy metal ions, highlighting its potential for application in the quality control of Chinese herbal medicines.