Luminescent europium(III)-organic framework for visual and on-site detection of hydrogen peroxide via a tablet computer

Abstract

A luminescent metal-organic framework of type Eu(III)-MOF has been fabricated for visual and on-site fluorometric determination of hydrogen peroxide (H2O2) via atabletcomputer. The maximum excitation and emission peaks of type Eu(III)-MOF were found at λex = 290nm and λem = 615nm, respectively. The average length of Eu-MOF is 1.21 ± 0.07μm. In the presence of the target H2O2, Fe2+ is transmitted into Fe3+ via Fenton reaction, leading to a fluorescence quenching of Eu-MOF. Therefore, visible color change occurred from bright red into colorless. Interestingly, by means of tablet computer's digital camera and ImageJ software, fluorescent signals were captured and transduced into digital parameters, resulting ina linear relationship between fluorescence intensity and the concentration of H2O2. As a result, the determination of H2O2 without the aid of complicated instruments is achieved in therange 2.0μM to 0.2mM with a detection limit of1.02μM. Our approach has beensuccessfully applied to quantify H2O2 in serum, urine, and waste water with good recovery and precision (< 2.5% RSD). Besides, our assay has beenexploited for visual detection of H2O2 released from HepG2 cells with the advantages of portability and accuracy. Moreover, the strategy displays acceptable selectivity and stability. Hence, our assay provides an alternative practical method for on-site determination of H2O2 without the need for instruments. Graphical abstract Schematic representation of the synthesis procedure of a luminescent Eu-MOF, which has been successfully applied for on-site detection of H2O2 via Fenton reaction and imaging analysis technique. The method exhibits handheld and accuracy for H2O2 determination, holding the potential for biochemical and clinical applications in remote regions.