Determination of Ascorbic Acid, Acetaminophen, and Caffeine in Urine, Blood Serum by Electrochemical Sensor Based on ZnO-Zn2SnO4-SnO2 Nanocomposite and Graphene

In the present research, a simple electrochemical sensor based on carbon paste electrode (CPE) modified with ZnO-Zn2SnO4-SnO2 and graphene (ZnO-Zn2SnO4-SnO2/Gr/CPE) was developed for direct, simultaneous individual measurement of Acetaminophen (AC), Caffeine (Caf) Ascorbic acid (AA). The synthesized nanomaterials were investigated using scanning electron microscopy, X-ray Diffraction, Fourier-transform infrared spectroscopy, impedance spectroscopy techniques. Cyclic voltammetry differential pulse applied investigation ZnO-Zn2SnO4-SnO2/Gr/CPE, impact scan rate concentration H+ electrodeâ??s responses investigated. voltammograms showed linear relationship between response oxidation AA, AC and, Caf in range 0.021â??120, 0.018â??85.3, 0.02â??97.51 μM detection limit 8.94, 6.66 7.09 nM (S/N = 3), respectively. Also, amperometric technique measuring target molecules 0.013â??16, 0.008â??12 0.01â??14 6.28, 3.64 3.85 nM, Besides, ZnO-Zn2SnO4-SnO2/Gr/CPE shows an excellent selectivity, stability, repeatability, reproducibility determination Caf. Finally, proposed successfully used to show amount urine, blood serum samples recoveries ranging 95.8% 104.06%. Keywords: Determination, Caffeine, Blood Serum, Voltammetry,