Quantitative Heterogeneous Immunoassays in Protein Modified Polydimethylsiloxane Microfluidic Channels for Rapid Detection of Disease Biomarkers

Conventional detection of disease biomarkers employs techniques such as lateral-flow assays or central laboratory-based enzyme-linked immunosorbent assays (ELISA). Miniaturization and performance improvement of such traditional immunoassays using microfluidic technologies has proved promising in producing rapid, sensitive and automated next-generation immunosensors for quantitative diagnoses in the point-of-care setting. In this article a poly(dimethylsiloxane) (PDMS)-based immunosensor is presented for rapid detection of C-reactive protein. PDMS is selected in part because of the vast popularity of using PDMS as a material for microfluidic devices and in part because of the challenge of obtaining a stable surface coating with PDMS for immunosensing applications. Practical procedures for fabrication, surface modification, and preservation of the microfluidic immuno-chips as well as detailed descriptions of performing the microfluidic heterogeneous assay are presented.