Graphene Oxide Electroreduced onto Boron-Doped Diamond and Electrodecorated with Silver (Ag/GO/BDD) Electrode for Tetracycline Detection in Aqueous Solution

Abstract

A new electrochemical sensor designed by modifying the commercial boron-doped diamond (BDD) electrode with graphene oxide (GO) reduced electrochemically and further electrodecorated with silver (Ag), named the Ag/GO/BDD electrode, was selected among a series of the BDD, GOelectroreduced onto BDD (GO/BDD) and silver electrodeposited onto BDD (Ag/BDD) electrodes for the detection of tetracycline (TC) in aqueous solution. The best results regarding the sensitivity of 46.6 µA·µM−1·cm−2 and the lowest limit of detection of 5 nM was achieved using square-wave voltammetry (SWV) operated at the step potential of 5 mV, modulation amplitude of 200 mV and the frequency of 10 Hz in alkaline medium. The application of the alkaline supporting electrolyte-based procedure is limited for water monitoring due to the presence of chloride that interferes with TC detection; however, it can be applied for quantitative determination of pharmaceutical formulations. 0.1 M Na2SO4 supporting electrolyte eliminated chloride interference and can be used for the application of Ag/GO/BDD in practical detection of TC in water.

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].…”

Electrochemical Method for Ease Determination of Sodium Diclofenac Trace Levels in Water Using Graphene—Multi-Walled Carbon Nanotubes Paste Electrode

“…The electroactive electrode areas were calculated by comparing the apparent diffusion coefficient value determined by classical method with the theoretical diffusion coefficient value of 6.70·10 −6 cm 2 ·s −1 reported in the literature data [ 41 ], and the results are presented in Table 2 . The electroactive surface areas determined for both CNT and GR-CNT paste electrodes were higher in comparison with the geometrical ones; GR-CNT exhibited the best electroactive area because the content of carbon was higher and the specific surface area was higher for GR than for CNT [ 42 ].…”

“…The lowest limit of detection (LOD) and the limit of the quantification (LQ) were determined on the basis of the equations of LOD = 3 SD/m and LQ = 10 SD/m, where SD is the standard deviation of three blanks and m is the slope of the analytical plots [ 41 ]. The reproducibility of the electrodes using the above-mentioned technique was evaluated by the relative standard deviation (RSD) for three replicates measurements of DCF concentration.…”

“…GR presence covered the structure of CNT, and it was significantly manifested through a more porous morphology. The electroactive electrode areas were calculated by comparing the apparent diffusion coefficient value determined by classical method with the theoretical diffusion coefficient value of 6.70•10 −6 cm 2 •s −1 reported in the literature data [41], and the results are presented in Table 2. The electroactive surface areas determined for both CNT and GR-CNT paste electrodes were higher in comparison with the geometrical ones; GR-CNT exhibited The electroactive electrode areas were calculated by comparing the apparent diffusion coefficient value determined by classical method with the theoretical diffusion coefficient value of 6.70•10 −6 cm 2 •s −1 reported in the literature data [41], and the results are presented in Table 2.…”

“…The electroactive electrode areas were calculated by comparing the apparent diffusion coefficient value determined by classical method with the theoretical diffusion coefficient value of 6.70•10 −6 cm 2 •s −1 reported in the literature data [41], and the results are presented in Table 2. The electroactive surface areas determined for both CNT and GR-CNT paste electrodes were higher in comparison with the geometrical ones; GR-CNT exhibited The electroactive electrode areas were calculated by comparing the apparent diffusion coefficient value determined by classical method with the theoretical diffusion coefficient value of 6.70•10 −6 cm 2 •s −1 reported in the literature data [41], and the results are presented in Table 2. The electroactive surface areas determined for both CNT and GR-CNT paste electrodes were higher in comparison with the geometrical ones; GR-CNT exhibited the best electroactive area because the content of carbon was higher and the specific surface area was higher for GR than for CNT [42].…”