%0 Journal Article %T Overoxidized Polypyrrole/ Gold Nanoparticles Composite Modified Screen-Printed Voltammetric Sensor for Quantitative Analysis of Methadone in Biological Fluids %J Analytical and Bioanalytical Electrochemistry %I Analytical and Bioanalytical Electrochemistry is an international scientific journal, which is published online every 3 months (since 2009), every 2 months (since 2011) and monthly (since 2018) by Center of Excellence in Electrochemistry, University of Tehran %Z - %A Shafaat, Atefeh %A Faridbod, Farnoush %D 2022 %\ 03/31/2022 %V 14 %N 3 %P 319-330 %! Overoxidized Polypyrrole/ Gold Nanoparticles Composite Modified Screen-Printed Voltammetric Sensor for Quantitative Analysis of Methadone in Biological Fluids %K Methadone %K Overoxidized polypyrrole %K Gold nanoparticles %K square wave voltammetry %K Biological fluids %R %X A highly sensitive voltammetric sensor for quantitative analysis of methadone in biofluids is introduced. The proposed sensor is based on screen-printed electrode (SPE) modification with overoxidized polypyrrole and gold nanoparticles composite (AuNPs/PPyox/SPE). Electrochemical measurements were carried out using square wave voltammetry (SWV). Morphological and electrochemical characterization of the proposed composite were studied using field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry. A wide linear range of 1 to 120 µmol L-1 and the limit of detection of 0.45 µmol L-1 in methadone analysis obtained by the presented sensor. The proposed sensor shows proper stability and high sensitivity in quantitative analysis of standard samples and can be successfully used for methadone determination in biological fluids.    %U https://www.abechem.com/article_251275_b3032d7cde7f3a24c9305cf0b3fddbfb.pdf