Hydrogel Immobilized-Antibodies for Protein Analysis

Gloria Thomas1, Laurie Locascio2, Michael Tarlov1

1Process Measurements Division

2Analytical Chemistry Division

The research described here explores the potential of microfluidics for biological assays of high specificity in areas such as biosensing, biological interaction and diagnosis of disease.  The conventional approach to developing such methods, particularly in areas of protein analysis, involves surface immobilization of probes to microchannel walls using surface chemistry and/or streptavidin/biotin linkages through multistep or coupled chemical reactions. These techniques often require extensive chemistry and offer poor stability.

Polymeric structures provide another approach for immobilizing probes in microchannels. Hydrogel plugs can be easily formed in microchannels within minutes using a photoinitiator. In this technique, large probes such as antibodies are included in the monomer solution and immobilized by physical entrapment upon polymerization.

In this presentation, hydrogel plugs capable of specific capture of target antigens are presented as demonstration of the potential of this method for protein based assays. The effects of channel treatment, hydrogel composition and incubation time will be illustrated using antibody/antigen model systems.