Enhanced electrochemical response of carbon quantum dot modified electrodes

M Algarra; A González-Calabuig; K Radotić; D Mutavdzic; C O Ania; J M Lázaro-Martínez; J Jiménez-Jiménez; E Rodríguez-Castellón; M Del Valle

doi:10.1016/j.talanta.2017.09.082

Enhanced electrochemical response of carbon quantum dot modified electrodes

Talanta. 2018 Feb 1:178:679-685. doi: 10.1016/j.talanta.2017.09.082. Epub 2017 Oct 5.

Authors

M Algarra¹, A González-Calabuig², K Radotić³, D Mutavdzic³, C O Ania⁴, J M Lázaro-Martínez⁵, J Jiménez-Jiménez⁶, E Rodríguez-Castellón⁶, M Del Valle⁷

Affiliations

¹ Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain. Electronic address: malgarra67@gmail.com.
² Sensors and Biosensors Group, Chemistry Department, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
³ Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11000 Beograd, Serbia.
⁴ CEMHTI (UPR 3079), CNRS, Univ. Orléans, 45071 Orléans, France.
⁵ Universidad de Buenos Aires, IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Departamento de Química Orgánica, Junín 956 (1113), CABA, Argentina.
⁶ Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain.
⁷ Sensors and Biosensors Group, Chemistry Department, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain. Electronic address: manel.delvalle@gmail.com.

PMID: 29136880
DOI: 10.1016/j.talanta.2017.09.082

Abstract

A glassy carbon electrode (GCE) was surface-modified with carbon quantum dots (CQDs) and applied for the effective enhancement of the electrochemical signal for dopamine and uric acid determination. CQDs were prepared from graphite by a green modification of the Hummers method. They were characterized by FTIR-ATR, XPS, solid-state NMR, fluorescence and Raman spectroscopies. TPD-MS analysis was applied to characterize the functionalization of the surface. The CQDs were assembled on the glassy carbon electrode by adsorption because of the large number of carboxy groups on their surface warrants effective adsorption. The modified GCE exhibits a sensitivity that is almost 10 times better than of the bare GCE. The lower limits of detection are 1.3μM for uric acid and 2.7μM for dopamine.

Keywords: Carbon dot; Modified electrode; Nanomaterial; Voltammetry.

MeSH terms

Carbon / chemistry*
Dopamine / analysis
Dopamine / chemistry
Electrochemistry / instrumentation*
Electrodes
Quantum Dots / chemistry*
Uric Acid / analysis
Uric Acid / chemistry

Substances

Uric Acid
Carbon
Dopamine