Desenvolvimento de células eletroquímicas com impressão 3D e escrita direta em papel para aplicações analíticas e bioanalíticas
Nenhuma Miniatura disponível
Data
2016-06-03
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal de Goiás
Resumo
This manuscript describes development of batch injection analysis (BIA) cells
using a 3D printer as well show the fabrication of pencil draw electrode on paper
platform. Bia cells were employed on wall-jet configuration coupled with
amperometric system. Bia systems were used to detect a product reaction
obtained by paper-microreactor and determine ethanol in whiskey samples.
Fabrication process using 3D printer was simple, fast (lower than four hours) and
cost effectiveness (ca. $ 3.43 and 1.07 to the 1st and 2nd generation of Bia system,
respectively). The 1st generation of Bia cell was production to be couple with
commercial screen printed electrodes (SPEs) by DropSens (DropSens, DPR 710
model) and 2nd generation have support to put home-made electrodes. Both Bia
cells, present a specific compartment to be coupled the micropipette. Paperbased
microreactors (MOPs) were used with the 1st generation of Bia cell and the
system was employed to measure glucose through the generation of hydrogen
peroxide by the reaction of glucose with glucose oxidase and amperometric
detection of H2O2 generated in the reaction at a potential of -0.25 V vs. Ag. In the
same way of Bia cell, MOPs fabrication process is simpler, faster and cheaper
(ca. $ 0.02 cent each). In general, the system shows a good linear response for
concentration range between 1 to 10 mmo L-1. The limit of detection (LD) and
quantification (LQ) found were 0.11 mmol L-1 and 0.38 mmol L-1, respectively.
Besides, the measure of glucose using five different MOPs presented a good
repeatability (RSD between 1.5 to 2.8%) and reproducibility (RSD = 0.66%). The
2nd generation of Bia cell was coupled with copper working electrode modified
thermally and chemically. This cell was employed to determine the presence of
ethanol in whisky sample using 1 mol L-1 NaOH as supporting electrolyte and
potential of 0.45 V vs Ag / AgCl. The modified-electrode shows optimum stability
to measure seventy minute of consecutive injection with RSD lower than 4.7%. A
good linear response was obtained when concentration of ethanol ranged from
2.5 to 25% (v/v). The LD achieved was ca. 0.07% (v/v). Besides the Bia cells
experiments, this work describes the fabrication process of alternative electrodes
by hand drawing pencil on paper platform. Initially, the geometry of sensing
electrodes was drawn using a graphic software and printed on paper surface.
During printing process, toner lines were deposited on paper to delimit the
electrode area. Then, the desire layout was draw using a pencil and laminated
using benchtop laminator. This last step is necessary to make the electrical
insulation. Fabrication process of alternative electrodes was simple, fast (~ 20
minutes) and cost effectiveness (ca. $ 0,023). Characterization of paper
electrodes was made by cyclic voltammetry with potassium ferrocyanide
(5 mmol L-1) in KCl solution (0.5 mol L-1). Besides, showed good peak separation
(ΔEp) ca. 238 mV and excellent reproducibility. The RSD was lower than 2.25%
to five different electrodes.
Descrição
Citação
DIAS, A. A. Desenvolvimento de células eletroquímicas com impressão 3D e escrita direta em papel para aplicações analíticas e bioanalíticas. 2016. 85 f. Dissertação (Mestrado em Química) - Universidade Federal de Goiás, Goiânia, 2016.