Three-dimensional electrochemical sensor with covalent organic framework decorated carbon nanotubes signal amplification for the detection of furazolidone

In this study, we developed a facile one-pot strategy for immobilizing a covalent organic framework (COF) on an amino-functionalized carbon nanotube (NH2-CNT) support at room temperature. The COF@NH2-CNT composite obtained possessed a high specific surface area (147.3 m(2) g(-1)), and good conductivity when deposited on the glassy carbon electrode (GCE). The COF@NH2-CNT/GCE sensor offered excellent analytical performance for the detection of the nitrofuran antibacterial agent furazolidone. The sensor offered a wide range furazolidone detection range from 0.2 mu M to 100 mu M, with a low limit of detection of 7.75 x 10(-8) M. The recovery test was performed in chicken and lamb samples with satisfactory recoveries ranged from 87.8%-126.9%. The furazolidone residues in beef and pork samples were determined using the COF@NH2-CNT/GCE sensor and high performance liquid chromatography. There was no significant difference between the two methods. The ability of the COF to efficiently adsorb furazolidone was a key to high sensitivity and fast response of the sensor platform. Results encourage the wider use of COFs in electrochemical sensor development.