integration

[helen]

What does it exactly mean - "foot point determination"? and "virtual baseline"?

[tom jupille]

I would have to see those phrases in context. They sound like translations into English by someone not fully familiar with the actual English technical idioms.

[helen]

There is a question about peak quantification and evalution of chromatograms.
The question is:
"Is the calculation always the same?
- foot point determination
- virtual base line
- integration parameter
- potential approximations, etc

[danko]

Foot point must be the peak start and the peak end – threshold.
The virtual baseline could be the line you draw when you integrate a peak.
As Tom mentioned above these are not widely accepted terms in chromatography, so don’t be embarrassed to ask the person who came up with these questions for a clarification.

Best Regards

[Jumpshooter]

I have a chromatogram of a peak has a slight fronting, I do not think it is the actual analyte b/c it's about 0.5 min before the analyte peak. But it caused the beginning side of the analyte peak to be up-slanted before it went down to the baseline near it's tail. Is it solvent? or is it actually some part of the peak that has made a shouldering? Any ideas?

[tom jupille]

It would really help to see the chromatogram. If you could generate a 400 x 400 pixel (approximately) image and post it, we could see what it actually looks like. A brief description of the embedding procedure is here:
http://www.sepsci.com/chromforum/viewtopic.php?t=2617