Authors: K.D. Barbee, A.P. Hsiao, E.E. Roller, X. Huang
Affilation: UCSD, United States
Pages: 50 - 53
Keywords: microbead arrays, multiplexed, protein detection, microfluidic
We report the development of a microfabricated electrophoretic device for assembling high-density arrays of antibody-conjugated microbeads for chip-based protein detection. The device consists of a flow cell formed between a gold-coated silicon chip with an array of microwells etched in a silicon dioxide film and a glass coverslip with a series of thin gold counter electrode lines. We have demonstrated that 0.4 and 1 µm beads conjugated with streptavidin, NeutrAvidin, or antibodies can be rapidly assembled into the microwells by applying a pulsed electric field across the chamber. We have shown that the antibody-conjugated microbead arrays can be used to perform on-chip sandwich immunoassays to detect test antigens at concentrations as low as 16 pM. This device will be useful for assembling high-density, encoded antibody arrays for multiplexed detection of proteins. Our fast and scalable assembly methods may also be extended to a multitude of other types of protein-conjugated microbeads for applications such as the analysis of protein-protein interactions.