Issue 4, 2019

Ratiometric detection of heavy metal ions using fluorescent carbon dots

Abstract

Classical methods for the detection of heavy metal ions in water are tedious and time consuming. Thus, there exists a need to develop novel sensing technologies for more sensitive and rapid detection. While optical-based assays using fluorescent nanomaterials have been reported, they are typically dependent on changes to the signal intensity, which brings about several disadvantages for potential environmental monitoring. Moreover, most of these systems only demonstrate selectivity and sensitivity to one cation. Herein, we report the use of a novel dual absorbing/fluorescing carbon dot system and develop a ratiometric assay to detect heavy metal ions such as Co2+, Fe3+, Hg2+, and Pb2+. These carbon dots simultaneously absorb and fluoresce in both blue and red regions of the spectrum. Their optical absorbance signature differs depending on the metallic cation present in solution and the absorbance pattern also varies as a function of the metal cation concentration. This effect is also seen in fluorescence assays where selective quenching of the red fluorescence is observed. This quenching behavior is ascribed to the interaction of the metallic cations with the fluorescent surface states of the carbon dot. Using either absorbance or fluorescence quenching assays, a linear response in the nanomolar range (1–961 nM) is observed with detection limits of 96.8, 61.7, 39.5, 37.1 nM for Co2+, Fe3+, Hg2+, and Pb2+, respectively.

Graphical abstract: Ratiometric detection of heavy metal ions using fluorescent carbon dots

Supplementary files

Article information

Article type
Paper
Submitted
17 dek 2018
Accepted
08 fev 2019
First published
08 fev 2019

Environ. Sci.: Nano, 2019,6, 1121-1130

Ratiometric detection of heavy metal ions using fluorescent carbon dots

F. Yarur, J. Macairan and R. Naccache, Environ. Sci.: Nano, 2019, 6, 1121 DOI: 10.1039/C8EN01418C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements