Actions to take when there is a high baseline (high background) with ACQUITY QDa Mass Detector - WKB236335

SYMPTOMS

• Higher baseline (background) than normal 

ENVIRONMENT

• ACQUITY QDa Mass Detector
• ACQUITY UPLC H-Class

CAUSE

FIX or WORKAROUND

1. Acquire data with flow set to 0.
   If the baseline is the same even when the flow is set to 0, there may be a problem with the QDa detector.
   If the baseline drops when the flow is set to 0, there may be a problem on the LC side.

2. If there is a problem on the LC side:
   (1) Prepare new mobile phase and replace the entire bottle.
   (2) Clean the mobile phase flowpath.
   　See the following KCS article for the cleaning procedures.
   　Be careful not to let the wash solvent enter the QDa detector.
   How to clean ACQUITY UPLC H-Class and I-Class Systems - WKB82038
   (3) Clean or replace the column.
   The easiest way to determine if there is a problem with the column is to replace it with another column of the same type (if available).
   If not available, clean the column and see if it works.
   For the cleaning procedures, refer to the instruction manual of the column used.

3. If there is a problem on the QDa detector:
   (1) Reboot the QDa detector.
   (2) Clean the QDa detector sample cone and replace the aperture disk.

ADDITIONAL INFORMATION