From flow injection to bead injection.

In this Report, we introduce a new methodology applicable to the entire range of traditional reagent and solid-phase assays. Known as bead injection (BI), this technique influences diverse fields of research, including chemical sensors, microfabrication, bioassays, affinity chromatography, spectrophotometry, and electrochemistry. This is because BI combines the advantages of solid-phase chemistry with the novelty of fluidic handling of microcarrier beads, allowing automated surface renewal and postanalysis manipulations. Surface renewal is an especially critical feature because assay surfaces become contaminated or otherwise dysfunctional with repeated use.