How to present chromatogram for Related substances method

[vijji21g]

Can i present two chromatograms of my sample for Related substances Method in GMP environment, where the 1st chromatogram will be in full scale, showing all the components of my sample and the 2nd chromtogram scaled such that the corresponding peaks of my related substances are clearly visible.

My concern is that if i present the 2nd option alone, questions regarding the complete info. might arise.

Plz. suggest

Thnx
Vijji

[nschwartz]

I have seen some reports where there was a need to show an expanded chromatogram for the impurity or a component of much lower concentration. Although numerical data will tell the story, you'll have to work a little harder to give a better picture visually. Depending on where you work and the data acquisition system, a technical writer may even be able to help you present what is needed.

[Sallybeetle]

Yes, you can present two chromatograms in a GMP environment. I made a one page report that contained all necessary information on the injection (sample name, lot #, injection size, etc.), a full scale chromatogram, and an off scale chromatogram.

The off scale chromatogram showed the critical part of the chromatgram up close. Sometimes the trace included the entire time range, just closer on the y-axis (absorbance, response). Sometimes I needed to show an up close view of a specific time range from the entire chromatogram. Sometimes I needed to include 2 or more off scale chromatograms in the report.

I believe that the 'trick' for a GMP environment is to include the full scale chromatogram and appropriate sample information. After that, include any off scale chromatogram to show the chromatography of the smaller peaks, etc.