Vanadium (III) -catechol functionalized copper metal–organic framework for sensitive detection of quercetin in biological fluids

Abstract

This study describes the preparation of a novel electrocatalyst based on catechol-vanadium charge transfer complex functionalized Copper-benzene 1,3,5- tricarboxylate MOF ((CAT-VIII)-Cu-BTC). The obtained structure is characterized by different analysis methods like XRD, TGA, SEM, EDAX/MAP, and FT-IR. UV–Vis spectrophotometry was applied to investigate the reaction between CAT and vanadate as well as the oxidation state of vanadium. All the analyses confirm the successful functionalizing of Cu-BTC with catechol-vanadium without any change in its crystalline structure. CAT-VIII /Cu-BTC was exploited to modify graphite paste electrode (GPE/CAT-VIII /Cu-BTC) for the detection of quercetin. The results showed that the functionalization of Cu-BTC with catechol-vanadium (III) causes increased electrocatalytic activity not only due to the presence of Cu ions but also due to the presence of vanadium ions. GPE/ (CAT-VIII)-Cu-BTC presents outstanding features toward electrooxidation of quercetin to a well-defined anodic peak at 0.5 V. The proposed sensor is introduced as a suitable alternative for quantitate sensing of QR in biological fluids.