User of 2695 Separations Module can address carryover problem - WKB88700

SYMPTOMS

• Repeated blank injection after sample injection
• Peak elutes at the sample retention time, and the intensity decreases gradually

ENVIRONMENT

• 2695 Separations Module

CAUSE

Sample carryover

FIX or WORKAROUND

1. Change the needle wash time.
   Change the “Needle wash time” from the “General” tab of the instrument method.
   Normal: about 13 seconds
   Double: twice the time of Normal
   Extended: four times the Normal
   
   
2. Use as needle wash solvent the solvent that dissolves the sample as much as possible.
   For example, if the carryover component is highly fat soluble:
   Change the order to ACN100%→ACN/IPA(6/4)→IPA100%→ACN/IPA/THF(4/3/3).
   If needed, acidify with acid such as 0.1% formic acid.
   If the carryover component is highly water-soluble, change the composition from 100% water to 100% ACN and verify.
3. Confirm peak with immediate injection.
   Performing immediate injection allows data acquisition without injection action.
   If no carryover peak is seen during immediate injection, the cause of carryover can be narrowed down to near the injector.
   
   

ADDITIONAL INFORMATION

2695 Separations Module システム洗浄方法

2695 Separations Module ユーザーでできるゴーストピーク対策