Analytical, Diagnostic and Therapeutic Techniques and Equipment Commons^™

Electronic Desalting For Controlling The Ionic Environment In Droplet-Based Biosensing Platforms, Vikhram Vilasur Swaminathan, Piyush Dak, Bobby Reddy Jr, Eric Salm, Carlos Duarte-Guevara, Yu Zhong, Andrew Fischer, Yi-Shao Liu, Rashid Bashir

Birck and NCN Publications

The ability to control the ionic environment in saline waters and aqueous electrolytes is useful for desalination as well as electronic biosensing. We demonstrate a method of electronic desalting at micro-scale through on-chip micro electrodes. We show that, while desalting is limited in bulk solutions with unlimited availability of salts, significant desalting of ≥1 mM solutions can be achieved in sub-nanoliter volume droplets with diameters of ∼250 μm. Within these droplets, by using platinum-black microelectrodes and electrochemical surface treatments, we can enhance the electrode surface area to achieve >99% and 41% salt removal in 1 mM and 10 mM salt …