General Considerations - Agilent Technologies 1290 Infinity II User Manual

General Considerations

The ELS Detector should be thought of as a detector like any other
designed for liquid chromatography. The main distinguishing feature is the
ability to evaporate the solvent from the column eluent. Therefore, normal
system set- up precautions should be remembered when starting to use the
instrument. Any solvent that is intended for use with the ELSD should be
fully miscible with any previously used in the liquid chromatograph. If
there is any uncertainty, then a mutually miscible solvent should be run
through the system as an intermediate liquid. The sample loop should also
be flushed with miscible solvent where necessary. The intended eluent
should be thoroughly degassed, should not contain non- volatile salts or
material and should be fully compatible with the column(s). All
connections should be made with zero dead volume fittings and tubing
with an I.D. ≤0.254 mm (≤0.010 in).
The ELSD requires nitrogen of purity >98 %, at an inlet pressure of 4 –
6.7 bar. If in- house nitrogen is not available, we recommend the use of a
nitrogen generator with a constant uninterrupted supply of high purity
gas. Air can be used with non- flammable solvent systems. The eluent of
choice should be fully volatile under the chosen detector parameters – any
non- volatilized eluent will increase baseline noise and reduce sensitivity.
The ELS Detector is a destructive technique and must be placed last when
used in series with other detectors, or used in conjunction with a flow
splitter for semi- preparative applications, where partial sample collection
is required.
Agilent 1290 Infinity II ELSD User Manual
Using the Module

General Considerations

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