Arrays of Screen‐Printed Graphite Microband Electrodes as a Versatile Electroanalysis Platform

Abstract

Arrays of microband electrodes were developed by screen printing followed by cutting, which enabled the realization of microband arrays at the cut edge. Microband arrays of different designs were characterised with physical and electrochemical methods. In both cases the methods showed that the microband width was around 5 m. Semi-steady-state cyclic voltammetry responses were observed for redox probes.Chronocoulometric measurements showed the establishment of convergent diffusion regimes characterized by current densities similar to those of a single microelectrode.The analytical performance of the elaborated electrode system and its versatility were illustrated with two electrochemical assays: detection of ascorbic acid via direct oxidation and a mediated glucose biosensor fabricated via dip coating. Due to convergent mass transport both systems showed enhancement of the analytical characteristics. The developed approach can be adapted to automated electrode recovery.

Evaluation of the Electrochemically Active Surface Area of Microelectrodes by Capacitive and Faradaic Currents

“…For comparison the geometric area was also calculated ( Figure 4A) based on a microband width of 7 � 1 μm, assessed by profilometry measurements and optical microscopy as reported previously. [24] The geometric and the faradaic EASAs agree quite well.…”

“…Gold macrodisk electrodes with a diameter of 2 mm, gold microdisk electrodes (AuME) with a diameter of 12.5 μm (CHI101 and CHI105, respectively, CH Instruments), screen‐printed graphite macrodisk electrodes with a diameter of 1.8 mm (Rusens LTD, Russia) and graphite microband arrays were used as working electrodes.…”

“…The graphite microband arrays were screen printed as described previously ( Figure 1A). [24] The graphite screen-printed microband arrays were used as working electrodes after cutting normal to the substrate surface with scissors. The microband working electrode was then connected to the potentiostat using a conductive adhesive tape and crocodile clips.…”

“…where a is the characteristic scale of the roughness (0.25 μm, 0.5 μm and 2 μm were used), b is a geometric parameter illustrating the number of periods within the microband electrode boundary (e. g. b = 5 for Figure 1B), w is the microband width estimated from optical measurements (7 μm) [24] and y ¼ ðÀ…”

Micro/Nano Electrode Array Sensors: Advances in Fabrication and Emerging Applications in Bioanalysis

“…Other preparation processes such as screen print, deposition, membrane formation, firing, etc. have also been used for micro electrode arrays fabrication (Mann and Mikkelsen, 2008;Vagin et al, 2014;Lee and Silvester, 2016). In addition, ink-jet and 3D printing technologies have recently become a powerful alternative processing tool for high-resolution microstructures which enables complex electrode patterns at micro scale (Nouran et al, 2018;Kundu et al, 2019).…”