How To Configure The Optimum Delay Volume - Agilent Technologies 1290 Infinity User Manual

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How to Optimize the Performance of Your Module

How to Configure the Optimum Delay Volume

How to Configure the Optimum Delay Volume

The design of the 1290 Infinity Quaternary Pump offers a strongly decreased
delay volume compared to standard 600 bar pressure pumps. For the 1290
Infinity Quaternary Pump, mixing is done in the multi-channel gradient valve
at ambient pressure. As all pump parts in the flow path after mixing
contribute to the delay volume, this includes also pump heads of the
quaternary pump, flow connections, filters, mixers etc. Therefore the delay
volume of a quaternary pump is by design larger than that of a binary pump.
All listed components including the inlet weaver and pump heads ensure a
good mixing performance resulting in excellent composition precision and
accuracy, highly reproducible retention times and low baseline noise. This
ensures best results for most applications.
Per default, the 1290 Infinity Quaternary Pump does not require and include a
Jet Weaver, as solvents are mixed in the MCGV and mixing is further improved
in the inlet weaver, pump heads and subsequent parts in the flow path.
Therefore, no Jet Weaver is required for most applications.
The V380 Jet Weaver high performance mixer is optionally available for
demanding applications, which use solvents in different channels (for example
A versus B), that differ strongly in their UV/Vis absorption, for example by
using trifluoroacetic acid (TFA) as a modifier, which has a high absorbance.
Solvent packages created by the pump may persist until the solvent reaches
the detector flow cell. Absorption fluctuations can then show up as baseline
noise, also referred to as mixing noise. Applications like impurity quantitation
or lowest level compound detection require minimizing this noise. The V380
Jet Weaver strongly improves mixing and therefore reduces baseline noise and
improves sensitivity in detection. Patented Agilent microfluidic technology
offers high mixing performance at a low internal volume of 380 μL, which is
the physical volume of all channels. It contributes with 150 μL to the pump
delay volume (< 350 μL without Jet Weaver), which is the partial mixer volume
that creates a composition change corresponding to the delay volume.
94 1290 Infinity Quaternary Pump User Manual