Application of Graphene Modified Carbon Paste Electrode for Simultaneous Determination of Acetaminophen, Dopamine and Ascorbic acid

Graphene is a family of carbon nanoscaled materials that is of great interest for pH sensors, biosensor and chemical sensor applications due to its intrinsic unique mechanical and electronic properties [1, 2]. Paracetamol (N-acetyl-p-amino-phenol) or acetaminophen (AC), is noncarcinogenic and an effective substitute for aspirin to be used for the patients who are sensitive to aspirin, and it is safe up to therapeutic doses.However, overdoses will cause liver and kidney damage and finally lead to death [3, 4]. Dopamine [4-(2-aminoethyl) benzene-1, 2-diol (DA)] plays an important role in the function of the central nervous, cardiovascular, renal and hormonal systems [5]. Insufficient DA concentration due to the loss of DA-producing cells may lead to a disease called Parkinson’s disease [6]. Ascorbic acid (AA) due to its characteristics such as, essential to the skin, immune system and connective tissues is important in health care of human beings [7]. In the present research, application of modified carbon paste electrode (CPE) with graphene was examined in determination of AC, DA and AA and their mixtures by electrochemical methods. The modified electrode exhibited strong function for resolving the overlapping voltammetric responses of AC, DA and AA into three well-defined voltammetric peaks. Differential pulse voltammetry peak currents of AC, DA and AA increased linearly with their concentrations at the ranges of 6.3×10−8-20.5×10−4 M, 7.0×10−8-7.8×10−4 M and 3.8×10−7-9.6×10−4 M respectively with a detection limits 0.43×10−8 M for AC, 0.65×10−8 M for DA and 0.25×10−7 M for AA. High sensitivity and selectivity, very low detection limit, the ease of preparation and surface regeneration of the modified electrode and reproducibility of the voltammetric responses suggest that this electrode very useful for accurate determination of AC, DA and AA in real samples.