It is vital to monitor the concentration of Cd(II) in rice which is considered to be one of the dominant sources of exposure to Cd(II) for human being. However, the complexity of rice samples makes it a challenge to realize the rapid and accurate determination of Cd in rice without interferences.
The anti-interference ability for several current approaches (especially electrochemical method) is expected to be dramatically improved. Therefore, it is very important to find an efficient system to improve the selectivity and accuracy of the Cd(II) determination in rice.
A research team led by Prof. HUANG Xingjiu and Prof. LIU Jinhuai from Institute of Intelligent Machines and Prof. ZHAO Nanjing from Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science of the Chinese Academy of Sciences achieves important progress on detecting the content of Cd(II) in rice with good anti-interference by electrochemical laser induced breakdown spectroscopy.
In their study, a methodology combined electrochemistry with laser-induced breakdown spectroscopy (EC-LIBS), as well as choice of negatively charged graphene oxides (GO(-)), was selected for the determination of trace Cd(II) in rice.
In this method, the target Cd(II) was preconcentrated on the surface of GO(-) modified Ti plate in the form of Cd(0) by electrochemcial deposition, the succeeding elemental identification and quantification was achieved by using LIBS.
Electrochemcial deposition and the modification of GO(-) on electrode significantly improved the sensitivity of the Cd(II) analysis in rice utilized LIBS only (for the same mass of rice sample) by three orders of magnitude and a ppb-level limits of detection (LOD) was obtained.
Good anti-interference ability was also achieved during the actual measurements, particularly when Cu(II) and Mn(II) co-existed. The combination of electrochemistry and LIBS techniques, as well as the presence of GO, made it very attractive for the purposes of Cd(II) sensing in standard and nonstandard conditions.
Most importantly, the study provides an extremely promising heavy metal ions sensing platform with potential application in more complicated operating conditions.
The study entitled Electrochemical laser induced breakdown spectroscopy for enhanced detection of Cd(II) without interference in rice on layer-by-layer assembly of graphene oxides was published in Electrochimica Acta.
This work is supported by the National High Technology Research and Development Program of China (863 Program) and the National Natural Science Foundation of China.
