HPLC peak shape

Hi all, 
I found a pic online while searching for solutions for my other problems. One of my HPLC system shows very similar problem like this pic. Does anyone know what cause the tails behave like this? I was thinking about buffer buildup in my system, however, after cleaning the system with hot water, the peak shapes didn't improve at all. Thanks for any help.


  • Neil
    Hello - did the peak shapes change over time?  IF so the column may have degraded.  If the peaks always tail then you have a mixed mode separation in the column and you may need to add some buffer to the mobile phase or search for a more appropriate column.  Neil
  • Nill
    Thank you for the answer. I already solved this issue. I also asked another question in a different thread, but they all have the same root cause---loose fitting.  Because of the loose fitting, there is a void in the tubing which interrupts the peak shape. What I did was to check all the tubing connections, and I found the ferrule and nut was loosened on the pump end. So I pushed the fitting further back up on the tubing, and the peak shape went back to normal. :)