Carryover solution that can be performed by user with 2695 Separations Module - WKB92691

SYMPTOMS

• Previously unseen peaks appear with the same analytical conditions
• Gradient with acetonitrile / water was used
• Ghost peak is detected with blank injection, and the area value of ghost peak does not decrease even after repeating the blank injection for multiple times.

ENVIRONMENT

• 2695 Separations Module
• 2489 UV/Vis Detector

CAUSE

The cause could be the solvent itself or the solvent bottle
If the peak is large, it is unlikely that it comes from acetonitrile.
If you want to check if it comes from water, you can measure the waste that has passed through a C18 Sep-Pak or a C18 column.
If the cause is the in-line filter, a replacement may be helpful.

FIX or WORKAROUND

1. Perform a immediate injection and a 0μL injection to determine if the injector is the cause of the ghost peak.
   If the peak is detected with 0µL injection and not detected with immediate injection, the injector should be considered as the cause.
   If the instrument has a frit, replace the frit.
   
   
   
2. If the ghost peak is also detected with immediate injection, directly connect the inline filter outlet to the column inlet and see if any ghost peaks.
   * By directly connecting the outlet of the in-line filter and the column inlet, the injector is separated from the flow path and you can tell if the problem is from injector or not.
3. If the ghost peak is still detected in step 2, the cause may be a flow path, mobile phase, or column other than the injector. Check the following.
   - Flow path other than the injector: Replacement of the in-line filter and suction filter, tube and ferrule on the column inlet/outlet, measurement with other lines (eg, if currently A/B is used, try with C/D)
   - Mobile phase: Preparation of new mobile phase, use of new mobile phase bottle, confirmation of whether additives are expired, confirmation of solvent grade being used
   - Column: Column replacement (cleaning if replacement is impossible)
4. Cleaning the entire system
   * See ADDITIONAL INFORMATION for cleaning method
5. To check if it comes from water, collect and measure the water that has passed through a C18 preparation column, or the waste that has passed through a C18 column if C18 preparation column is not available.

ADDITIONAL INFORMATION

Carryover solution that can be performed by user with 2695 Separations Module - WKB88700

2695 Separations Module System Cleaning