Constructing a simple and sensitive electrochemical sensor for the determination of NMN based on p-m-ABSA film modified glassy carbon electrode

In the present study, a novel and facile poly-m-amino-benzenesulfonic acid (p-m-ABSA) film on glassy carbon electrode (GCE) was developed using pulse potentiostatic method (PPM), which is employed with the oxidative polymerization of m-ABSA at anode potential. Meanwhile, a simple and sensitive sensor was fabricated to detect normetanephrine (NMN), which is one of the significant diagnostic markers for diseases. Compared with bare GCE, the p-m-ABSA film prepared on GCE surface has the advantage of increasing electrode surface area and active sites distinctly, thus obviously improving the electrocatalytic activity. The results demonstrated that the developed electrochemical sensor exhibited high sensitivity, stability, selectivity and excellent electrocatalytic activity towards NMN. The surface morphology of p-m-ABSA/GCE was characterized by scanning electron microscopy (SEM), indicating that the electrode surface had a layered structure. The preparation conditions and analysis methods of sensors were studied in detail. Under optimum conditions, peak current and concentrations of NMN were linearly related well from 0.5 to 30.0 mu M with a limit of detection (S/N = =3) of 0.17 mu M. Moreover, this modified sensor has also been successfully used for the detection of NMN in human serum samples.