Novel three-dimensional electrochemical sensor with dual signal amplification based on MoS2 nanosheets and high-conductive NH2-MWCNT@COF for sulfamerazine determination

A novel three dimensional electrochemical sensor with signal amplification and selective recognition of sulfa-merazine (SMR) was successfully constructed. First, highly conductive amino-functionalized carbon nanotubes@covalent organic frameworks (NH2-MWCNT@COF) and molybdenum disulfide (MoS2) nanosheets were employed to modify the glassy carbon electrode (GCE) by simple physical deposition, in order to enhance the SMR response signal. Then, molecularly imprinted polymer (MIP) membrane was anchored on the surface of this modified GCE by electrochemical polymerization to achieve selective recognition for SMR. The electrochemical performance of the assembled electrochemical sensor was systematically investigated with differential pulse voltammetry and cyclic voltammetry. This obtained sensor displayed excellent selectivity for SMR and good reproducibility. Under optimal conditions, the sensor offered a wide current response for SMR from 3.0 x 10(-7) to 2.0 x 10(-4) mol L-1, with a limit of detection of 1.1 x 10(-7) mol L-1. Furthermore, this developed sensor was successfully applied for the determination of SMR in pork and chicken samples with recoveries of 86.0%-102.0%, and results correlated well with those obtained by high-performance liquid chromatography.