- admin
- Site Admin
-
- Posts: 647
- Joined: Wed Aug 11, 2004 12:19 am
Hi,
We are using an Agilent HPLC 1100 and a DAD detector. Recently we encounter some problems: negative peaks in the chromatograms. It is the same chromatograms that we are getting normally except that everything is "inverted".
The method is as follows:
MP A: 0.05%TFA in H2O
MP B: 0.05%TFA in ACN
Time A(%) B(%)
0 100 0
8 95 5
9 100 0
11 100 0
We have encounter this problem thrice. We tried to use H2O to wash the system and the detector (as advised by the vendor), it works but the problem returns after a while. The method is validated and we did not make any changes to the settings. Can anyone enlighten us on this? Thanks in advance!
-------------------------------------------------------------------------------------------------------
By rob burgess on Wednesday, July 7, 2004 - 07:30 am:
Have you got the polarity settings right on your detector? If not its simple to change.
-------------------------------------------------------------------------------------------------------
By Anonymous on Wednesday, July 7, 2004 - 05:50 pm:
Hi Rob,
Thanks for your reply. How do we check the polarity settings?
-------------------------------------------------------------------------------------------------------
By rob burgess on Thursday, July 8, 2004 - 04:34 am:
We use hand held control modules to control our Agilent systems. Its just then a matter of going to the detector settings and changing there. Consult your user manual if in doubt.