Chromatography Forum

This may be a silly question, but it has been confusing me.

I am making some injections of known concentrations for my experiments. For some of the calculations I want to make, I need the concentration of my analytes in the mobile phase to produce the correct graph.

Do I need to solve some differential equation (since conc. is a function of time and position in the column)? Or could I just use the void volume of the column as a factor that is diluting my known injection concentration?

Thanks for any assistance!

The time when your Peak starts and Ends will give you the volume in which your compound is solved. If flow is 1ml per min and this time is half a Minute your analyt is disolved in half a ml. Maybe that Explanation is too easy and some colleagues will give you the right equation. We will see.

The time when your Peak starts and Ends will give you the volume in which your compound is solved. If flow is 1ml per min and this time is half a Minute your analyt is disolved in half a ml. Maybe that Explanation is too easy and some colleagues will give you the right equation. We will see.

That seems to makes sense. I will try that out with some of my calculations and see if the results make sense. Thank you.

The time when your Peak starts and Ends will give you the volume in which your compound is solved. If flow is 1ml per min and this time is half a Minute your analyte is dissolved in half a ml.

That assumes that your starting point was the peak area (i.e., that you have already integrated the peak). If you are using peak height, and you have a Gaussian peak, you need to divide by 2 (the maximum amplitude is approximately twice the average).