Agilent Technologies G1157A, User Manual

Page: 45 / 78

Agilent 1200 Series Valves 45
Valve Applications 4
Sample enrichment and Sample stripping
For the sample enrichment phase the valve is switched to position 1. The
eluent Pump A transfers the injected sample onto the enrichment column. The
sample is retained and enriched on this column, whereas the sample matrix is
flushed into the waste. At the same time the second eluent pump B is
equilibrating the analytical column.
After the valve is switched to position 2 pump B is backflushing the sample on
the analytical column for separation and subsequent detection by LC/MS or
optical detectors.
Agilent Technologies offers capillary kit for sample enrichment and sample
stripping. The content is listed in
Table 11 on page 46 and Table 12 on page 47.
Sample stripping
Sample stripping is another method to remove complex sample matrices. In
difference to sample enrichment the matrix is trapped on the pre-column
while the analytes pass through onto the analytical column.
Figure 21 Sample stripping (schematic setup)