Three electrode electrochemical microfluidic cell: construction and characterization

Abstract

Este trabalho descreve a construção e caracterização de uma célula eletroquímica microfluídica com a inserção dos três eletrodos (trabalho, pseudo-referência e auxiliar) em microcanais com espessuras menores que 20 µm. Os microcanais foram construídos entre duas bases de policarbonato com o uso de uma ou mais máscaras de toner sobrepostas como espaçador. Esta estratégia permite a construção de microcélulas com um volume interno sobre o eletrodo de trabalho entre 0,6 a 2,4 µL. Três diferentes materiais foram otimizados como eletrodos nas microcélulas: filmes de ouro ou compósito de grafite como eletrodo de trabalho, compósito de prata como pseudo-referência e compósito de grafite como eletrodo auxiliar. O desempenho das células microfluídicas foi avaliado usando as técnicas de voltametria cíclica, redissolução potenciométrica a corrente constante e voltametria de redissolução anódica por onda quadrada empregando ferrocianeto e alguns metais pesados (Cu This work describes the construction and characterization of an electrochemical flow-through microcell with the three electrodes (working, pseudo-reference, and auxiliary) inserted in microchannels with thickness smaller than 20 µm. These microchannels were constructed between two stacked polycarbonate slides using one or more overlapped toner masks as spacer. This strategy allows the construction of microcells with a variable internal volume on the working electrode (0.6 to 2.4 µL). Three different materials were optimized as electrodes: gold film or graphiteepoxy composite as working electrode, silver-epoxy composite as pseudo-reference electrode and, graphite-epoxy composite as auxiliary electrode. The performance of the microfluidic cell was characterized by cyclic voltammetry, potentiometric stripping analysis at constant current, and square wave anodic stripping voltammetry using ferrocyanide and heavy metals (Cu

Analytical chemistry in Brazil: healthy and growing

“…In another work, a three electrode electrochemical microfluidic cell was proposed and characterized. 290 The electrodes were inserted in microchannels with lower than 20 mm thickness, constructed between two polycarbonate slides, using toner masks as spacer. Internal volume was within the 0.6 to 2.5 mL range and analytical performance was evaluated by means of cyclic voltammetry, potentiometric stripping analysis and square wave anodic stripping voltammetry.…”

Colorimetric Detection of Glucose in Biological Fluids Using Toner-Based Microzone Plates

“…Recent publications have also demonstrated the use of LPT to produce tunable hydrophobic valves 17 as well as polyester-toner devices for microdroplets generation 18 and reciprocating mixers. 19 Additional examples regarded to the indirect use of toner for the fabrication of electroanalytical devices, [20][21][22][23][24][25] microchip free-flow electrophoresis, 26 polymer microfluidic devices [27][28][29] and integrated microfluidic cell devices have been also reported. 30 Due to the advantages associated with the fabrication simplicity and low cost per device, some authors have extended the use of LPT to produce toner-based devices for clinical assays involving the use of portable equipment like cell phone camera, scanner, digital camera and handheld optical microscope for colorimetric measurements.…”

Three‐Electrode‐Integrated Sensor into a Micropipette Tip

“…Different materials have been applied to produce miniaturized electrodes which can be used in small volume samples such as gold [11][12][13], silver [13], platinum [14] and copper wires (i.d. up to 200 mm) [15], thin gold films obtained from CD-Rs [16][17][18], carbon paste electrodes [19], graphite composite [17,20], silver composite [17,18], and stainless steel needles [21,22].…”