| Abstract: | A micro-analytical platform for performing electrophoresis-based
immunoassays was developed by integrating photopolymerized cross-linked
polyacrylamide gels within a microfluidic device. The microfluidic
immunoassays are performed by gel electrophoretic separation and
quantifying analyte concentration based upon conventional polyacrylamide
gel electrophoresis (PAGE). To retain biological activity of proteins and
maintain intact immune complexes, native PAGE conditions were employed.
Both direct (non-competitive) and competitive immunoassay formats are
demonstrated in microchips for detecting toxins and biomarkers
(cytokines, c-reactive protein) in bodily fluids (serum, saliva, oral
fluids). Further, a description of gradient gels fabrication is included,
in an effort to describe methods we have developed for further
optimization of on-chip PAGE immunoassays. The described chip-based PAGE
immunoassay method enables immunoassays that are fast (minutes) and
require very small amounts of sample (less than a few microliters). Use
of microfabricated chips as a platform enables integration, parallel
assays, automation and development of portable devices. |