Waters ACQUITY UPLC M-Class - Page 68

Suspected cause Possible solution
Inlet lines blocked • Inspect lines for blockages and replace
tubing if necessary.
• Clean the solvent inlet filter frit and replace
the frit if necessary.
Mobile phase contaminated See also: Controlling Contamination in Ultra
Performance LC/MS and HPLC/MS Systems
on the documentation CD.
Fluid leak Refer to the applicable solvent manager
overview and maintenance guide on the
documentation CD.
4.3.2.4 Broad peaks
Suspected cause Possible solution
Detector time constant or filter is too high (non-
MS detectors).
Ensure that time constant is as low as possible
while still minimizing baseline noise.
MS detector scan rate is too low. Increase the scan rate to obtain more data
points across the peak.
User observes too much peak smoothing. Reduce smoothing to prevent peak shape
distortion.
4.3.2.5 Early eluting peak issues
Suspected cause Possible solution
Injection volume or sample concentration is too
high.
• Reduce the injection volume.
• Dilute the sample.
Sample diluent too high in organic for the initial
mobile phase.
Reduce the injection volume or reduce the
percentage of organic in the diluent.
Needle weak wash solvent is too high in
organic.
Ensure that the needle wash solution is similar
to the initial mobile phase.
The method or part of the method is isocratic. Use a gradient method in which all peaks are
typically the same width.
User observes incorrect trapping or column
conditions.
Review the trapping parameters and reset to
improve conditions.
November 26, 2019, 715003588 Revision C
Page 68