{"title":"Sensitive electrochemical detection of dopamine using CuCo2O4/graphene quantum dots-modified carbon paste electrode","authors":"Masoumeh Madadi , Masoud Rohani Moghadam , Parisa Salarizadeh , Alireza Bazmandegan-Shamili , Mehdi Shahbakhsh","doi":"10.1016/j.inoche.2024.113566","DOIUrl":null,"url":null,"abstract":"<div><div>This research investigates the fabrication and electrochemical characterization of a modified graphene paste electrode (MCPE) incorporating CuCo<sub>2</sub>O<sub>4</sub> bimetallic oxide and its composite with graphene quantum dots (GQDs) for dopamine detection. The CuCo<sub>2</sub>O<sub>4</sub> was synthesized via a hydrothermal method. The oxidation–reduction behavior of dopamine on the GQD/CuCo<sub>2</sub>O<sub>4</sub>/CPE indicates a quasi-reversible electrochemical reaction with an absorption-controlled electron transfer process and the kinetics of the catalytic reaction followed pseudo first-order. The average value of the electron transfer rate constant for GQD/CuCo<sub>2</sub>O<sub>4</sub> was observed to be 0.047 s<sup>−1</sup>. Characterization of the obtained materials was performed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). Subsequently, under optimized conditions, cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were employed to evaluate the dopamine sensing performance of the MCPEs. The GQD/CuCo<sub>2</sub>O<sub>4</sub> composite electrode exhibited a lower detection limit (0.004 μM) and quantification limit (0.013 μM) for DA compared to the CuCo<sub>2</sub>O<sub>4</sub> electrode (0.0088 μM and 0.030 μM, respectively). The GQD/CuCo<sub>2</sub>O<sub>4</sub> nanocomposite showed better sensitivity (33.0 mA/mM) than CuCo<sub>2</sub>O<sub>4</sub> (17.9 mA/mM) due to the superior conducting nature of GQD. Finally, the applicability of the GQD/CuCo<sub>2</sub>O<sub>4</sub>-based MCPE was demonstrated by measuring DA in real samples.</div></div>","PeriodicalId":13609,"journal":{"name":"Inorganic Chemistry Communications","volume":"171 ","pages":"Article 113566"},"PeriodicalIF":4.4000,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Inorganic Chemistry Communications","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1387700324015569","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
This research investigates the fabrication and electrochemical characterization of a modified graphene paste electrode (MCPE) incorporating CuCo2O4 bimetallic oxide and its composite with graphene quantum dots (GQDs) for dopamine detection. The CuCo2O4 was synthesized via a hydrothermal method. The oxidation–reduction behavior of dopamine on the GQD/CuCo2O4/CPE indicates a quasi-reversible electrochemical reaction with an absorption-controlled electron transfer process and the kinetics of the catalytic reaction followed pseudo first-order. The average value of the electron transfer rate constant for GQD/CuCo2O4 was observed to be 0.047 s−1. Characterization of the obtained materials was performed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). Subsequently, under optimized conditions, cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were employed to evaluate the dopamine sensing performance of the MCPEs. The GQD/CuCo2O4 composite electrode exhibited a lower detection limit (0.004 μM) and quantification limit (0.013 μM) for DA compared to the CuCo2O4 electrode (0.0088 μM and 0.030 μM, respectively). The GQD/CuCo2O4 nanocomposite showed better sensitivity (33.0 mA/mM) than CuCo2O4 (17.9 mA/mM) due to the superior conducting nature of GQD. Finally, the applicability of the GQD/CuCo2O4-based MCPE was demonstrated by measuring DA in real samples.
期刊介绍:
Launched in January 1998, Inorganic Chemistry Communications is an international journal dedicated to the rapid publication of short communications in the major areas of inorganic, organometallic and supramolecular chemistry. Topics include synthetic and reaction chemistry, kinetics and mechanisms of reactions, bioinorganic chemistry, photochemistry and the use of metal and organometallic compounds in stoichiometric and catalytic synthesis or organic compounds.