Agilent Technologies 1290 Infinity User Manual page 18

1
Introduction to the Agilent 1290 Infinity Valve Drive and Valve Heads
Typical Applications
Enrichment methods
Enrichment methods are the technique of choice to obtain highest sensitivity
and to remove the sample matrix in such applications as proteomics, drug
metabolism and environmental trace analysis. The analytes are retained and
concentrated onto the pre-column, while the sample matrix is passed to waste.
After the valve switch, a second pump backflushes the analytes out of the
pre-column onto the separation column. This allows injection of large volumes
onto the pre-column, significantly expanding sensitivity in the range of ten to
several thousands.
Stripping methods
Stripping methods handle analytes and matrices in the opposite way to
enrichment methods. Matrix components are retained on the pre-column
while the analytes pass through to the separation column. After the valve
switches, an additional pump backflushes the matrix components out of the
pre-column to waste, while the analytes are separated on the main column.
Backflushing prepares the pre-column for the next injection.
Alternating Column Regeneration
Only 2pos/10port valve (p/n G4232A/B)
Advantages:
• High sample throughput
• Increased productivity
• High efficiency
Alternating column regeneration is a convenient way to increase the sample
throughput. The Agilent 1200 Infinity Series 2 position/ 10 port valves can be
used to increase the efficiency in laboratories running large amounts of
samples. Gradient elution is a common technique for separation of complex
samples in liquid chromatography, which requires column regeneration before
the subsequent run is started. Using alternating column regeneration valuable
time for the analysis is saved. Core of the alternating column regeneration is
the Agilent 1200 Infinity Series 2 position / 10 port valves, which allows
simultaneous analysis on one column while a second identical column is
flushed and equilibrated.
18 Agilent 1290 Infinity Valve Drive and Valve Heads