High-Throughput Single-Entity Electrochemistry with Microelectrode Arrays

We describe micro- and nanoelectrode array analysis with an automated version of the array microcell method (AMCM). Characterization of hundreds of electrodes, with diameters ranging from 100 nm to 2 μm, was carried out by using AMCM voltammetry and chronoamperometry. The influence of solvent evaporation on mass transport in the AMCM pipette and the resultant electrochemical response were investigated, with experimental results supported by finite element method simulations. We also describe the application of AMCM to high-throughput single-entity electrochemistry in measurements of stochastic nanoparticle impacts. Collision experiments recorded 3270 single-particle events from 671 electrodes. Data collection parameters were optimized to enable these experiments to be completed in a few hours, and the collision transient sizes were analyzed with a U-Net deep learning model. Elucidation of collision transient sizes by histograms from these experiments was enhanced due to the large sample size possible with AMCM.