Development of a microfabricated electrochemical-cantilever hybrid platform

The design and fabrication of a combined electrochemical-cantilever microfluidic system is described. A chip integrating cantilevers with electrodes into a microchannel is presented with the accompanying polymer flow cell. Issues such as electrical and fluid connections are addressed, electromechanical behavior in ionic solution is investigated, and two uses of the system are demonstrated. First, all cantilevers are functionalized with cysteine, to facilitate detection of Cu2+ ions, then one cantilever is electrochemically cleaned in situ to generate a reference cantilever for differential measurements. Two concentrations of Cu2+ ions are successfully measured in this way. Clean cantilevers are used to probe a solution with and without [Fe(CN)6]3−/4− redox couple present, demonstrating the combined voltammetric and deflection readout.