AS-AP Poor RSD or inconsistent peak areas

Issue

One or more of the following is occurring:

• System is not reproducible and is not reliable
• Injections are varying from sample to sample
• Poor RSD

Environment

AS-AP Autosampler

Resolution

1. The placement of the 2 green waste lines are important to maintain consistent area response as an incorrect waste lines can siphon liquid causing poor area reproducibility. See the AS-AP Operator's Manual.
   
2. Be sure the sample loop, syringe size and buffer loop used on your hardware matches what’s in the configuration.  Below are the default settings:
   
   
    
3. See slide below for more causes of poor RSD:
   
    
   1. You can change the puncture offset of the sampler in the “commands” 
      
      
   2. You must set the command level to “expert” by right clicking in the left pane in the red circle area and setting to “expert”
      
      
4. Be sure your 250ul syringe on the ASAP is fully primed with no air bubbles. Any air bubbles will cause poor RSD.  It a good idea to run these 3 action items before every sequence to ensure the sampler is fully primed:
   
   
    

5. If any air bubbles are still present, remove the syringe, prime by hand, and reconnect the syringe.

6. If reproducibility issues persist, replace the suppressor.