Rapid detection of cadmium ions in meat by a multi-walled carbon nanotubes enhanced metal-organic framework modified electrochemical sensor

Abstract This work presents an electrochemical device based on a composite modification of amine functionalized Zr(IV) metal-organic framework (UiO-66-NH2) and multi-walled carbon nanotubes (MWCNTs) for voltammetry determination of cadmium ions (Cd2+). The UiO-66-NH2@MWCNTs composites were prepared by one-pot hydrothermal reaction. The prepared sensor performs excellent performance, which was attributed to the synergism between UiO-66-NH2 with a special octahedral structure and enlarged surface area and MWCNTs with outstanding conductivity. Under optimal experiment condition, the fabricated sensor showed good linear relationship from 0.5 to 170 μg/L, with a detection limit of 0.2 μg/L. Finally, the sensor was successfully applied to detect Cd2+ in meat samples (N=21) with relative standard deviation (RSD) lower than 4.5% and recovery of 95.1-107.5%, and the results were compared with certified method, there was no statistical significance difference between the developed sensor and certified method at a 95% confidence level.