On-Demand Electrochemical Activation of the Click Reaction on Self-Assembled Monolayers on Gold Presenting Masked Acetylene Groups

We report on a new surface modification method for grafting a "dynamic" property for on-demand activation of the click reaction. Our approach utilizes the acetylene group masked with dicobalt hexacarbonyl, Co-2-(CO)(6), which is not reactive toward the click reaction. Electrochemical treatment reveals the acetylene group on the selected region, which is then used as a chemical handle for surface functionalization via the click reaction with an azide-containing molecule. Electrochemical and chemical conversions on the surface were verified by cyclic voltammetry, X-ray photoelectron spectroscopy, and fluorescence spectroscopy. We have demonstrated immobilization of an azide-modified RGD peptide and promotion of cell adhesion/migration to the region of electrochemical induction.