Multiplexed Protein Detection Using Antibody-conjugated Microbead Arrays Assembled on a Microfabricated Electrophoretic Device

We present a method for conducting sensitive, multiplexed immunoassays on antibody-conjugated microbeads that have been assembled into an array in a microfabricated electrophoretic device. This device improves upon our previous work through the use of more robust dielectric and counter electrode materials. The array of micron to submicron wells is fabricated in a silicon dioxide film on a gold-coated wafer and the counter electrodes consist of a series of gold lines fabricated on a glass coverslip. These substrates are assembled together with pre-cut double-coated adhesive tape to form microfluidic channels. Antibody-conjugated microbeads are then introduced into the fluidic channels and assembled into high-density arrays using a series of electric pulses. Our method and device can be used to produce dense antibody arrays with extremely small footprints in less than 30 seconds.