A copper(II)/cobalt(II) organic gel with enhanced peroxidase-like activity for fluorometric determination of hydrogen peroxide and glucose
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A bimetallic organic gel was prepared by mixing the bridging ligand 2,4,6-tri(4-carboxyphenyl)-1,3,5-triazine with Cu(II) and Co(II) ions at room temperature. The resulting metal-organic gel (MOG) shows enhanced peroxidase-like activity, most likely due to the synergetic redox cycling between Co(III)/Co(II) and Cu(II)/Cu(I) pairs. These accelerate interfacial electron transfer and generation of hydroxy radicals. The MOG can catalyze the reaction of H2O2 with terephthalic acid (TPA), producing a blue fluorescence product with the maximum excitation/emission at 315/446 nm. The enzyme mimic was used to design a fluorometric method for H2O2 that has a 81 nM detection limit. H2O2 is also formed by glucose oxidase-assisted oxidation of glucose by oxygen, and an assay for glucose was worked out based on the above method. It has a 0.33 μM detection limit. This study may open up a new avenue to design and synthesize nanomaterial-based biomimetic catalysts with multiple metal synergistically enhanced catalytic activity for potential applications in biocatalysis, bioassays and nano-biomedicine.
KeywordsPeroxidase mimetic Redox cycle Synergistic effect Metal-organic gel Enzyme mimic Terephthalic acid 2-hydroxyterephthalic acid Fluorescence Catalysis Hydroxy radicals
The authors are grateful to the National Natural Science Foundation of China (NSFC, No. 21575117).
Compliance with ethical standards
The author(s) declare that they have no competing interests.
- 8.Chen WH, Vazquez-Gonzalez M, Kozell A, Cecconello A, Willner I (2018) Cu2+-modified metal-organic framework nanoparticles: a peroxidase-mimicking Nanoenzyme. Small 14(5):1–8Google Scholar
- 22.Okesola BO, Smith DK (2016) Applying low-molecular weight supramolecular gelators in an environmental setting-self-assembled gels as smart materials for pollutant removal. ChemSocRev 45(15):4226–4251Google Scholar
- 32.Lin JM, Shan XQ, Hanaoka SC, Yamada M (2001) Luminol Chemiluminescence in unbuffered solutions with a cobalt(II)-ethanolamine complex immobilized on resin as catalyst and its application to analysis. Analchem 73:5043–5051Google Scholar