Jump to main content
Jump to site search


Specific enzymatic synthesis of 2,3-diaminophenazine and copper nanoclusters used for dual-emitting ratiometric and naked-eye visual fluorescence sensing of choline

Abstract

This work demonstrated a novel, facile and efficient biosensor for dual-emitting ratiometric and visual fluorescence detection of choline. Copper nanoclusters (CuNCs) were prepared by using N2H4·H2O as the reducing agent and lysozyme as the stabilizer, based on an ambient hydrothermal method. The prepared CuNCs were blue-emitting and had an emission center peaked at 440 nm. In the mixture system consisting of CuNCs, choline oxidase, horseradish peroxidase (HRP) and o-phenylenediamine (OPD), the added choline was catalyzed by choline oxidase to generate H2O2. OPD was oxidized by H2O2 and HRP to generate 2,3-diaminophenazine (DAP). As the oxidation product of OPD, DAP emitted a fluorescence peaked at 550 nm and the fluorescence exhibited a regular enhancement with the increase of choline concentration. Meanwhile, CuNCs’ fluorescence was reduced by DAP due to an internal filtration effect-induced fluorescence quenching. There is an optimal linear relationship (r = 0.9992) between ratiometric fluorescence intensity (IDAP/ICuNCs, I550/I440) and choline concentration in the range of 0.1−80 μM, with a low limit of detection of 25 nM. The response of IDAP/ICuNCs to choline was sensitive and selective, over potential interferents existing in real samples. This developed sensor enabled the naked-eye visual detection of choline in aqueous solutions and on immersed filter papers. In human serum and liquid milk samples, this sensor had a superior performance for choline detection.

Back to tab navigation

Supplementary files

Publication details

The article was received on 04 Aug 2018, accepted on 11 Sep 2018 and first published on 12 Sep 2018


Article type: Paper
DOI: 10.1039/C8NJ03927E
Citation: New J. Chem., 2018, Accepted Manuscript
  •   Request permissions

    Specific enzymatic synthesis of 2,3-diaminophenazine and copper nanoclusters used for dual-emitting ratiometric and naked-eye visual fluorescence sensing of choline

    X. Bu, Y. Fu, H. Jin and R. Gui, New J. Chem., 2018, Accepted Manuscript , DOI: 10.1039/C8NJ03927E

Search articles by author

Spotlight

Advertisements