Highlights • The redox sensitive mucus is affected by oxygen gradients, effecting gut physiology. • Demonstrating oxidative homeostasis is crucial to mimic cell-bacteria communication. • Organ-on-Chip systems lack the complexity to mimic the redox state in the mucus. • Electrochemical sensors and redox mediators may assist mimicking the mucosa layer. Within the gastrointestinal tract, the mucosal layer, which is the physical and homeostatic barrier between the microbiome and the host, exhibits redox molecules such as mucin molecules and oxidative species generating oxygen gradient. These molecules control the mucosal structural state and affect cross-communication in the microbiome. Gut-on-Chip platforms are Organ-on-Chip devices that tend to imitate gut physiology; however, the crucial oxidative state in the epithelial-microbiome barrier is not well represented in these platforms. The ability to properly mimic the gentle communication between the prokaryotic and eukaryotic kingdoms in the gut requires contemporary electrochemical and Organ-on-Chip tools. In this review article, we highlight the redox-dependent functional states in the mucosal layer, discuss the current advancements in Gut-on-Chip devices, present the challenges remaining in such devices to properly mimic the mucosa layer, and recommend an innovative approach involving the integration of label-free electrochemical sensors within the Gut-on-Chip platform. Graphical abstract Download : Download high-res image (359KB) Download : Download full-size image

To achieve carbon neutrality by 2050, there is an urgent need to transition from major power sources to renewable energy and electrify various manufacturing technologies. This is also inevitable in the production of basic organic chemicals, which are used as raw materials in pharmaceuticals and agrochemicals, entailing organic chemical production processes that significantly reduce heat consumption. Therefore, the electrosynthesis of organic chemical products, as an enabling technology for electrification in the chemical industry, has received considerable attention. This study outlines the history, features, and challenges involved in organic electrosynthesis and introduces organic electrosynthetic processes using solid polymer electrolyte (SPE) reactors, which have the potential to realize carbon neutrality. Graphical abstract Download : Download high-res image (182KB) Download : Download full-size image

Highlights • The principles of split-bipolar electrodes are discussed. • Split-bipolar electrodes are described in relation to conventional bipolar electrodes. • The use of split-bipolar electrodes for electrochemical fluorination of small organic molecules is summarized. • The use of split-bipolar electrodes for electrosynthesis of conducting polymers is summarized. Bipolar electrochemistry has recently gained renewed interest as a valuable electrochemical technique for electrosynthesis applications. The peculiarity of this technology is the wireless mode of electrode reactions, that is redox processes can be driven on a conductive material, namely a bipolar electrode (BPE), without the need for an ohmic contact. A split-BPE (s-BPE) is a particular type of BPE, where two conductors are connected using an ammeter that is placed outside the electrolytic solution. While this configuration allows the two conductors to behave like a single BPE, the main advantage of such a system is that the current can be measured in situ, promoting the search for the optimized set of conditions for a successful electrosynthesis application. Herein, we review the latest trends in electrifying synthesis that exploit the concept of s-BPE for electrosynthesis of polymeric materials and electrochemical fluorination of small organic molecules.