Guanhong Liu, Xinyi Li, Jun Wang, Youtao Song,

College of Environment, Liaoning University

Haishuang Jia, Zhiyue Yu

College of Chemistry, Liaoning University

Na Li

Department of Clinical Laboratory, Shengjing Hospital of China Medical University

Abstract

Carbon dots (CDs) as a kind of environment-friendly fluorescent nanomaterial has been actively studied because of wide and potential applications, such as bioimaging and biosensors. It is worth mentioning that preparing CDs from the recycling of carbonaceous waste has received considerable research interest. We proposed a simple carbon dots synthesis technique, that is, using China grass carp scales (CGCS) as original and green materials by a one-step microwave hydrothermal method to prepare CDs. Since the mercury ion has strongly sulphophile, S atoms display higher thermodynamic affinity and faster integrating process with Hg²⁺ ions. Due to the presence of large amount of cysteine-containing sulfhydryl groups, the obtained CGCS-CDs can be used as a specific fluorescence probe for detecting Hg²⁺ ions. Subsequently, CGCS-CDs were characterized by HR-TEM, XRD, FTIR and XPS analyses. The optical properties of CGCS-CDs were elucidated by fluorescence and UV–vis spectra. Additionally, the effects of pH values and salt concentrations on optical properties of CGCS-CDs were also researched by fluorescence spectra. Under optimal conditions, the decrease of fluorescence intensity displays a good linear relationship with allowable Hg²⁺ ion detection concentration range of 0.014–30 μmol/L and a limit of detection (LOD) of 0.014 μmol/L is acquired. Meanwhile, the effect of other metal ions on the detection of Hg²⁺ ions by using CGCS-CDs as fluorescence probe was studied, suggesting that the CGCS-CDs could be an excellent fluorescence probe for the detection of Hg²⁺ ions. Eventually, the CGCS-CDs were proven to be low toxicity and applied for Hg²⁺ ions detection in lake water and cosmetic, demonstrating their potential towards diverse applications.

Read the full article here:   67-High-fluorescent carbon dots (CDs) originated from China grass carp scales (CGCS) for effective detection of Hg(II) ions.pdf