Chromatography Forum

Deal All

Please clarify my questions

1. Why base line drift is observed, if we run in gradient programms.

The base line starts with zero and slowly increasing.

2. In gradient runs, while reaching high % of oraganic we are getting number of balnk peaks. These blank peaks is interfearing with sample peaks. so how to avoid these type of problems. % organic is much needed because non-polar compounds elution purpose.

regards
ramesh

Here.
viewtopic.php?t=10153

Csaba gave you the answer for negative drift and mohan, sort of, a reason for positive drift. Please check the forum even further, there are many explanations for the peaks you observe, for instance, that there may be dirt in the solvent with the lower elution power (the dirt is retained until the solvent of higher elution power moves it out).

There is a 15-minute "mini-seminar" on this problem available for viewing on our web site:
http://www.lcresources.com/more_resourc ... hp?f=3&t=5

You will have to register (free) to view the presentation