Cu(I) Coordination Complex Precursor for Randomized CuOx Microarray Loaded on Carbon Nanofiber with Excellent Electrocatalytic Performance for Electrochemical Glucose Detection

Abstract

A homoleptic ionic Cu(I) coordination complex that was based on 2,2′-biquinoline ligand functionalized with long alkyl chains (Cu(I)–C18) was used as a precursor to modify a carbon nanofiber paste electrode (Cu–C18/CNF). Randomized copper oxide microelectrode arrays dispersed within carbon nanofiber paste (CuOx/CNF) were obtained by electrochemical treatment of Cu–C18/CNF while using cyclic voltammetry (CV). The CuOx/CNF exhibited high electrocatalytic activity towards glucose oxidation at +0.6 V and +1.2 V vs. Ag/AgCl. Infrared Spectroscopy (FTIR) and scanning electron microscopy (SEM) characterized the electrodes composition. Cyclic voltammetry (CV), square wave-voltammetry (SWV), and multiple-pulsed amperometry (MPA) techniques provided optimized conditions for glucose oxidation and detection. A preconcentration step that involved 10 minutes accumulation at open circuit potential before SWV running led to the lowest limit of detection and the highest sensitivity for glucose detection (5419.77 µA·mM−1·cm−2 at + 1.1 V vs. Ag/AgCl) vs. Cu-based electrodes reported to date in literature.

Graphene Quantum Dots and Cu(I) Liquid Crystal for Advanced Electrochemical Detection of Doxorubicine in Aqueous Solutions

“…Even if in the EU there are no legal standards for the presence of human cytostatic and cytostatic medical products in water, these compounds belong to emerging pollutants, Cu, Ag nanoparticles [17][18][19][20][31][32][33]. Very interesting behavior and application utility in sensitive sensing have been reported for homoleptic ionic Cu(I) coordination complex based on 2,2 -biquinoline ligand functionalized with long alkyl chains (Cu(I)_BF 4 ) integrated within carbon nanofiber paste electrode [19].…”

A comprehensive review summarizing the recent biomedical applications of functionalized carbon nanofibers

“…In this design, Fe and Cu developed a multiscale hierarchical web of ACFs/CNFs, and glucose oxidase was immobilized on the tips. Sorina et al used a homoleptic ionic Cu complex made of 2,2′‐biquinoline ligands conjugated with long alkyl chain (C18‐Cu) for glucose detection 70 . Several conducting polymers are used for glucose detection 71 .…”

Wearable Noninvasive Glucose Sensor Based on CuxO NFs/Cu NPs Nanocomposites

“…Cu(II) oxide and Cu(I) oxide are widely known copper oxides that have outstanding sensing capacities. An electron pair reaction involving the redox couple ions Cu(III) and Cu(II) formed the foundation for the sensing mechanism [ 24 , 25 ]. The continuous transformation of electrons was available by the redox pair ions, which serve as an intermediary mediator [ 26 , 27 , 28 , 29 ].…”