Chromatography Forum

Posted: **Tue Oct 10, 2006 3:34 pm**

Hi
I am a new user of the HPLC, and I have a new column for the HPLC. The column is an ACCQ.Tag amino acid analyis column. I am trying to do a plate count for this column following the instructions and I don't get a peek. Why??? I run a standard 0.05% Acenaphthene in acetonitrile and let it run 60/40 for 10 min the inject of 10 micro L. I get no peek.
Am I doing something wrong?
Tracy

Posted: **Tue Oct 10, 2006 5:36 pm**

My first suspicion would be that you have a problem with the sample dissolution. Make a sample with a much higher concentration, and then dilute.
Also check if the QC method for the column uses indeed 60% acetonitrile and 40% water. Then check if indeed you have made the composition with a higher concentration of acetonitrile, and not by accident the other way round.

Posted: **Tue Oct 10, 2006 6:32 pm**

Also check your detector/data system settings to confirm the proper wavelength, absorbance range, etc.