3D-printing pen versus desktop 3D-printers: Fabrication of carbon black/polylactic acid electrodes for single-drop detection of 2,4,6-trinitrotoluene.

Autor: Cardoso RM; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil., Rocha DP; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil., Rocha RG; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil., Stefano JS; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil., Silva RAB; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil., Richter EM; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil., Muñoz RAA; Center for Research on Electroanalysis (NuPE), Institute of Chemistry, Federal University of Uberlândia, 38408-100, Uberlândia, MG, Brazil. Electronic address: munoz@ufu.br.
Jazyk: angličtina
Zdroj: Analytica chimica acta [Anal Chim Acta] 2020 Oct 02; Vol. 1132, pp. 10-19. Date of Electronic Publication: 2020 Jul 30.
DOI: 10.1016/j.aca.2020.07.034
Abstrakt: The fabrication of carbon black/polylactic acid (PLA) electrodes using a 3D printing pen is presented and compared with electrodes obtained by a desktop fused deposition modelling (FDM) 3D printer. The 3D pen was used for the fast production of electrodes in two designs using customized 3D printed parts to act as template and guide the reproducible application of the 3D pen: (i) a single working electrode at the bottom of a 3D-printed cylindrical body and (ii) a three-electrode system on a 3D-printed planar substrate. Both devices were electrochemically characterized using the redox probe [Fe(CN) 6 ] 3-/4- via cyclic voltammetry, which presented similar performance to an FDM 3D-printed electrode or a commercial screen-printed carbon electrode (SPE) regarding peak-to-peak separation (ΔEp) and current density. The surface treatment of the carbon black/PLA electrodes fabricated by both 3D pen and FDM 3D-printing procedures provided substantial improvement of the electrochemical activity by removing excess of PLA, which was confirmed by scanning electron microscopic images for electrodes fabricated by both procedures. Structural defects were not inserted after the electrochemical treatment as shown by Raman spectra (i D /i G ), which indicates that the use of 3D pen can replace desktop 3D printers for electrode fabrication. Inter-electrode precision for the best device fabricated using the 3D pen (three-electrode system) was 4% (n = 5) considering current density and anodic peak potential for the redox probe. This device was applied for the detection of 2,4,6-trinitrotoluene (TNT) via square-wave voltammetry of a single-drop of 100 μL placed upon the thee-electrode system, resulting in three reduction peaks commonly verified for TNT on carbon electrodes. Limit of detection of 1.5 μmol L -1 , linear range from 5 to 500 μmol L -1 and RSD lower than 4% for 10 repetitive measurements of 100 μmol L -1 TNT were obtained. The proposed devices can be reused after polishing on sandpaper generating new electrode surfaces, which is an extra advantage over chemically-modified electrochemical sensors applied for TNT detection.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2020 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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