Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)A simple procedure for the simultaneous determination of acetaminophen (AC) and ascorbic acid (AA) by differential pulse voltammetry (DPV) using a carbon nanotube paste electrode exploiting measures in cetylpyridinium bromide (CPB) medium is described. Under the best instrumental parameters of DPV, optimized by means of factorial design, the calibration plots in the range 100.0700.0 mu mol?L-1 (r=0.993) and 39.4146.3 mu mol?L-1 (r=0.995) with limits of detection of 7.1 and 2.1 mu mol?L-1, were achieved for AA and AC, respectively. The developed method was successfully applied for the AC and AA determination in pharmaceutical formulations, whose accuracy was attested by comparison with HPLC method.241222912301Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)UEL (Universidade Estadual de Londrina)INCT for Bianalytics (Instituto Nacional de Ciencia e Tecnologia de Bioanalitica)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)