Differential pulse voltammetric analysis of lead in vegetables using a surface amino-functionalized exfoliated graphite nanoplatelet chemically modified electrode

A surface amino-functionalized (CONH2) exfoliated graphite nanoplatelet (xGnP) bismuth-modified electrode (CONH2xGnP/glassy carbon electrode GCE) for the determination of lead was developed and characterized. The hybrid material was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The electrochemical properties of the CONH2xGnP bismuth-modified electrode were characterized by a physical deposition method, depositing the film on a graphite electrode. The differential pulse response was linear over the Pb(II) concentration range of 0.005–0.045 μg L−1, with a limit of detection of 0.001 μg L−1, and the linear regression equation was y = 3.75x + 0.73. In vegetable juice (cabbage), the current increased linearly relative to the Pb(II) concentrations over the concentration range 0.005–0.035 μg L−1 with the corresponding linear regression equations: y = 13.06x + 0.46, R2 = 0.9970.