Mobile Phase Guidelines For The Detector - Thermo Scientific Vanquish VF-D20 Operating Manual

6.5.1

Mobile Phase Guidelines for the Detector

General Guidelines
Vanquish Charged Aerosol Detectors Operating Manual
CAUTION—Explosion Hazard or Damage to the Detector
When using tetrahydrofuran (THF), the use of air as supplied gas may
pose an explosion hazard. This can pose a safety and health risk and
damage the detector. Always use nitrogen with tetrahydrofuran or other
highly combustible solvents.
NOTICE Inappropriate or contaminated mobile phase can damage the
detector. The quality of the mobile phase significantly influences the
performance of the detector. Observe the following guidelines to avoid
damage to the detector.
•
Use only volatile mobile phases. All constituents, i.e. solvents and
additives, of the mobile phase should be sufficiently volatile to allow
evaporation under the conditions used.
•
Non-volatile solutes in the mobile phase, even at trace amounts,
produce a detector signal (background current, noise, drift).
Minimize their concentration.
TIP A careful consideration in the selection of the mobile phase
components will be helpful in minimizing the baseline noise and
optimizing the performance during analysis.
Observe the following guidelines to minimize the concentration of non-
volatile matter in the mobile phase:
•
Prepare all mobile phases with volatile solvents and additives that
have low residue after evaporation such as high-purity water,
LC/MS-grade solvents and reagent-grade chemicals.
TIP Use water from an ultra-pure deionized source, as it typically has
low conductivity and high resistivity.
6 • Operation
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