Advances and Perspectives in Chemical Imaging in Cellular Environments Using Electrochemical Methods

Abstract

This review discusses a broad range of recent advances (2013)(2014)(2015)(2016)(2017) in chemical imaging using electrochemical methods, with a particular focus on techniques that have been applied to study cellular processes, or techniques that show promise for use in this field in the future. Non-scanning techniques such as microelectrode arrays (MEAs) offer high time-resolution (<10 ms) imaging; however, at reduced spatial resolution. In contrast, scanning electrochemical probe microscopies (SEPMs) offer higher spatial resolution (as low as a few nm per pixel) imaging, with images collected typically over many minutes. Recent significant research efforts to improve the spatial resolution of SEPMs using nanoscale probes and to improve the temporal resolution using fast scanning have resulted in movie (multiple frame) imaging with frame rates as low as a few seconds per image. Many SEPM techniques lack chemical specificity or have poor selectivity (defined by the choice of applied potential for redox-active species). This can be improved using multifunctional probes, ion-selective electrodes and tip-integrated biosensors, although additional effort may be required to preserve sensor performance after miniaturization of these probes. We discuss advances to the field of electrochemical imaging, and technological developments which are anticipated to extend the range of processes that can be studied. This includes imaging cellular processes with increased sensor selectivity and at much improved spatiotemporal resolution than has been previously customary.

Nanoscale Electrochemical Mapping

“…16 The popularity of SECM, in particular, and SEPM in general, for single cell electrochemical imaging and life sciences applications, is reflected in a number of recent review articles. [17][18][19][20][21][22] SEPM is a key enabling technology for the emerging fields of single entity electrochemistry and electrochemistry at nano-interfaces, for which there were seminal Faraday Discussion meetings in 2016 and 2018, respectively. The published volumes of these meetings 23, 24 contain not only original papers, but also extensive discussions of key issues.…”

Differential Electrochemicolor Imaging Using LSI-based Device for Simultaneous Detection of Multiple Analytes

“…In the near future, this imaging technique will be used to monitor the release of dopamine from cells in the presence of ascorbic acid without potential scanning, e.g., by fast-scan voltammetry, although the interaction between dopamine and ascorbic acid during electrochemical detection would have to be carefully investigated. Previously, electrode arrays were applied to three-dimensional tissue organs; hence, (23)(24)(25)(26) we also aim to investigate the current system for possible application in this regard, such as in organs-on-a-chip. Figure 6(a) shows amperograms for various concentrations of PAP and PAPP.…”

Untitled

“…Стремление к уменьшению объемов анализируемых растворов, что особенно важно при анализе медико-биологических образцов, привело к созданию планарных пленочных электродов, полученных методом трафаретной печати. Такие screen-printed электроды обычно имеют толщину порядка 20-50 мкм, и могут быть изготовлены из бумаги, полимерной или керамической подложки, или других подручных материалов с нанесением на их поверхность с помощью трафарета электропроводящей пасты или чернил, в которую вводится активный модификатор [17,18,19]. Такие электроды не содержат ртуть, обладают хорошими аналитическими характеристиками, просты в конструкции, отличаются низкой стоимостью, универсальны в определении объектов различной природы.…”