Fig. 1. Conceptual illustration of the flow-through microfluidic device integrated with Au nanorods for one-step immunoassay of protein biomarkers.

The serum sample containing target biomarkers is introduced and conjugated with the fluorescent dAb prepatterned in the deposition zone. The complex flows through the reaction chamber and is captured by cAb conjugated with dense arrays of embedded Au nanorods. The enhanced fluorescent signals are measured and analyzed through a microscope equipped with a CCD camera. The flow rate and total reaction time are defined by the capillary pump