Doble Role Of Bathocuproine Disulfonic Acid As Multi-Walled Carbon Nanotubes Dispersing Agent And Copper Preconcentration Ligand: Analytical Applications For The Development Of Hydrogen Peroxide And Glucose Electrochemical Sensors

GALLAY, PABLO; RODRÍGUEZ, MARCELA; EGUÍLAZ, MARCOS; RIVAS, GUSTAVO

JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS

ELSEVIER SCIENCE BV

Año: 2020

0731-7085

We are reporting a new strategy for preparing carbon nanotubes (CNTs)-based hydrogen peroxide and glucose amperometric sensors by taking advantage of the dual role of bathocuproine disulfonic acid (BCS) as dispersing agent of multi-walled carbon nanotubes (MWCNTs) and as ligand for the preconcentration of Cu(II). The platform was obtained by casting glassy carbon electrodes (GCE) with the dispersion of MWCNTs in BCS (MWCNTs-BCS) followed by the preconcentration of Cu(II) by surface complex formation at open circuit potential (GCE/MWCNTs-BCS/Cu). The resulting electrode was used for the sensitive amperometric quantification of hydrogen peroxide at 0.400 V catalyzed by the preconcentrated copper, with a linear range between 5.0 × 10-7 and 7.4 × 10-6 M, a sensitivity of 24.3 mA.M-1, and a detection limit of 0.2 μM. The adsorption of GOx at GCE/MWCNTs-BCS/Cu followed by the immobilization of Nafion (Naf), allowed the construction of a sensitive and selective amperometric glucose biosensor with a linear range between 5.0 × 10-6 M and 4.9 × 10-4 M, a sensitivity of (477 ± 3) μA.M-1 and a detection limit of 2 μM. The proposed (bio)sensors were successfully used for the quantification of hydrogen peroxide in enriched milk samples and glucose in milk and commercial beverages without any pretreatment.