Here we described the development of a simple methodology for quantification of acetaminophen (ACOP) using square-wave voltammetry (SWV). A glassy carbon electrode modified with gold nanoparticles, functionalized multi-walled carbon nanotubes and cobalt (II) phthalocyanine was prepared and characterized with cyclic voltammetry, SWV and electrochemical impedance spectroscopy. The optimum experimental conditions, such as pH, buffer and square-wave voltammetric parameters were investigated. From the data analysis of the optimization of experimental conditions, the oxidation of ACOP was characterized as a quasi-reversible and proton-dependent process, where the reaction mechanism presents the participation of equal number of protons and electrons (two protons and two electrons) and k(s) value is equal to 59.0 +/- 25 s(-1). Under the optimized conditions, calibration curves were linear in the concentration range of 1.49 mu mol L-1 to 47.6 mu mol L-1 and 47.6 mu mol L-1 to 107.0 mu mol L-1 with a limit of detection of 0.135 mu mol L-1. Other analytical parameters such as equations of the analytical curves, correlation coefficients, recovery efficiency and relative standard deviation for repeatability and reproducibility experiments were compared to results obtained by the use of UV-Vis spectrophotometry. (C) 2016 Elsevier B.V. All rights, reserved.