Towards a Surface Microarray based Multiplexed Immunoassay on a Digital Microfluidics Platform

The use of digital microfluidics (DMF) for sample handling in a microarray immunoassay was investigated. A two plate DMF device was used, with the top plate being used for the immobilization of antibodies for a sandwich immunoassay. A patterning procedure was developed for the top plate to expose patches of glass that were chemically modified, using silane chemistry, to allow for the covalent immobilization of antibodies. For creating microarrays, a set of parallel microchannels were used for the high density patterning of proteins onto the functionalized surface of the top plate. This patterning procedure was optimized to ensure the reproducibility of the immobilization and the physical integrity of the top plate. Preliminary work for a multiplexed immunoassay such as verification of cross-reactivity and detection schemes was also conducted. This work represents the initial efforts towards a microarray immunoassay on DMF, which has the potential to improve high throughput analysis.MAS