Figure 5.

Schematic of the two positions of a stationary-phase-assisted modulation (SPAM) interface. Rather than using large storage loops, analytes are effectively filtered out of the ¹D effluent using low-volume trapping columns. Optionally, the ¹D column effluent may be diluted using a weak eluent to facilitate retention on the traps. Moreover, the waste line may be equipped with a detector to monitor premature elution from the traps during method development. (Multiple) heart-cut 2D-LC setups are possible as long as the multiple traps are identical.