Nanoscale Electrochemical Sensing and Processing in Microreactors
Annual Review of Analytical Chemistry
In this review, we summarize recent advances in nanoscale electrochemistry, including the use of nanoparticles, carbon nanomaterials, and nanowires. Exciting developments are reported for nanoscale redox cycling devices, which can chemically amplify signal readout. We also discuss promising high-frequency techniques such as nanocapacitive CMOS sensor arrays or heterodyning. In addition, we review electrochemical microreactors for use in (drug) synthesis, biocatalysis, water treatment, or to
... reatment, or to electrochemically degrade urea for use in a portable artificial kidney. Electrochemical microreactors are also used in combination with mass spectrometry, e.g., to study the mimicry of drug metabolism or to allow electrochemical protein digestion. The review concludes with an outlook on future perspectives in both nanoscale electrochemical sensing and electrochemical microreactors. For sensors, we see a future in wearables and the Internet of Things. In microreactors, a future goal is to monitor the electrochemical conversions more precisely or ultimately in situ by combining other spectroscopic techniques. Redox cycling can be described as the effect of a reversible redox molecule cycling between an oxidizing and reducing electrode pair. For each cycle, the same single molecule contributes to the measured current, effectively amplifying the signal by chemical means (22) . Meaningful 424 Odijk · van den Berg Annual Rev. Anal. Chem. 2018.11:421-440. Downloaded from www.annualreviews.org by m.odijk@utwente.