Since each step of a flow based assay is best performed at a different flow rate,  flow programming is an important component for optimization of reagent based assays. The  SI protocol for reagent-based assays uses the following combination of flow rates:

WASH fast flow rates for flush the system with carrier solution
INJECT sample and reagent zones at flow rates no higher than the  injected volume
REACT for SHC protocol uses  stop flow, for SFC protocol  uses volume (return volume), which will place the reacting zone within the flow cell at an  intermediate flow rate
MONITOR for SHC protocol uses volume that will push the peak maximum into the flow cell, using a moderate flow rate to collect data. For SFC protocol stop the flow for a desired time interval.

For adsorption of analyte on a microcolumn use very low flow a column (1 to 5 µL/sec). For analyte desorption from microcolumn  use low flow rates (5µL/sec)

Flow Programming for SHC and SFC