A glassy carbon electrode modified with MCM-41/nickel hydroxide nanoparticle/multiwalled carbon nanotube composite as a sensor for the simultaneous determination of dopamine, piroxicam, and cefixime

The present work demonstrates that simultaneous determination of dopamine (DA), piroxicam (PRX), and cefixime (CEF) can be performed on the composite of multiwalled carbon nanotubes (MWCNTs), nickel hydroxide nanoparticles (NHNPs), and MCM-41 modified glassy carbon electrode (MWCNTs-NHNPs-MCM-41/GCE). The effect of the composition of MWCNTs, NHNPs, and MCM-41 for the modification of GCE was tested, and the mixture of 5 % NHNPs, 10 % MCM-41, and 85 % MWCNTs was chosen for the fabrication of the sensor. The MWCNTs-NHNPs-MCM-41 composite was characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) analysis. Under optimum conditions, the application of differential pulse voltammetry method showed the linear relationship between oxidation peak currents, and the corresponding concentrations of DA, PRX, and CEF were 0.2-85, 0.1-70, and 0.1-200 mu M with detection limits of 0.07, 0.04, and 0.05 mu M, respectively. The proposed method was used in the determination of these compounds in human urine and blood serum samples with satisfactory results.