Chromatography Forum

Hello guys, I am new here and I need help with my chromatograms. I am rookie at this and did it for the first time. For the introduction, we had few samples and we wanted to determine the amount of compound in a sample. I have selected one mass (775 m/z) from TIC chromatogram in different samples. I was told to integrate the peaks in chromatograms (I don't know if it is integrated correct, I did for an ilustration|. Only I see there the numbers are decreasing from the top to bottom. I would like to know few facts. Please help me.
a) Did i get the amount of the area under cover like in chromatography with for example UV detector ? Or is intensity of this ion (775m/z) or what does that number above a peak mean?
b) Is it possible to determine somehow the quantity of the product if i know the concentration of solution used for analysis?
c) If I can't use it to determine accurate concentration. Is it possible at least to compare the samples in which is more or less of that compound (775m/z) from these numbers ?
I really appreciate all the help from anybody.
Thank you.

Here is the image with chromatograms

http://postimg.org/image/c1avety2d/

Okaaaay

First of all, if those are SIM, it looks like you have at least five compounds that give that fragment.
It looks like the integration bunched them all together.

what does that number above a peak mean?

The two numbers above each bunch represent the retention time of the highest peak in the bunch and the total area of the bunch.

Is it possible to determine somehow the quantity of the product if i know the concentration of solution used for analysis?

Not unless you have run standards at known concentrations bracketing the concentration you are looking at. Then you can compare the area of your peak to the area of the standards to get quantitation.

Is it possible at least to compare the samples in which is more or less of that compound (775m/z) from these numbers ?

You could, but I wouldn't put much faith in the values. Ionization efficiency can change as the interface gets dirty with repeated samples. You really should run a known check sample periodically to confirm that ionization is consistent (or, even better, use an appropriate internal standard).

All of that said, unless you understand why you are getting a cluster of peaks from the chromatography, any quantitation in this case is little better than guesswork.