We performed FSCV using a custom-built integration unit that includes a Dagan Chem-Clamp (Dagan Corporation, Minneapolis, MN, USA), National Instrument data acquisition cards (National Instrument, Austin, TX), Dagan-compatible headstage (Pine Research Instrumentation, Durham, NC), and WCCV 4.0 software (Knowmad Technologies LLC, Tucson, AZ, USA). All experiments were performed in a Faraday cage (AutoMate, Berkeley, CA, USA) with a two-electrode system Please do not adjust margins Please do not adjust margins comprised of a pseudo-Ag/AgCl reference (made in-house) and the CFM working electrode. We cycled the electrodes in each solution for 10 min prior to any data acquisition. The waveform we used for Cu(II) measurements was developed by Hashemi and colleagues (-1 V to 0.8 V at 400 V/s scan rate and a resting at 0 V, 10 Hz). All data was processed in Microsoft Excel and GraphPad Prism 9. Error bars and uncertainties are all reported as SEM.