Cu,Zr-BTC/CNT composite for electrochemical detection of endocrine disruptor bisphenol A

Endocrine disruptors that may be present in plastic wastes can leach into surface water, pollute the environment and our drinking water; they must be monitored. In this study, an electrochemical sensor based on a metal organic framework (Cu, Zr-BTC) combined with carbon nanotubes (CNT) was developed for rapid on-site detection of bisphenol A-the most widely used monomer in plastics production. The Cu, Zr-BTC/CNT composite was first prepared by a solvothermal process in DMF solvent at 100 degrees C. For the first time, the Zr-based MOF with high proton conductivity was combined with Cu-based MOF with large active area in the same framework to provide an efficient platform for electrochemical detection. Morphological and structural studies revealed the coordination of Cu2+ and Zr4+ ions with organic ligands in a highly porous framework (active surface area up to 673 m2 g-1). The use of highly conductive carbon nanotube material is to improve the recorded electrochemical signals. The developed bisphenol A sensor showed a linear response for bisphenol A concentrations from 2 to 50 mu M, with a detection limit down to 0.5 mu M and a sensitivity of 0.45 mu A.mu M-1 cm-2. The sensors produced gave reproducible results (relative standard deviation of less than 7%) and were stable (relative standard deviation less than 12% after several days of storage). Tests on real samples were performed on Hanoi tap water and showed a satisfactory recovery (92-95%). The results were validated using high performance liquid chromatography. These results demonstrate the possibility of using such MOF materials in sensor applications.

Automated summary

In this study, an electrochemical sensor based on a metal organic framework (Cu, Zr-BTC) combined with carbon nanotubes (CNT) was developed for rapid on-site detection of bisphenol A. The sensor showed a linear response for bisphenol A concentrations, with a low detection limit and good stability. The results demonstrate the potential use of MOF materials in sensor applications.