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Trying to finish my Dissertation however i am struggling due to some incoherent data. The experimental i used was based on an assigned practical from my prior year that had stock solutions provided, one addition was made to repeat the experiment with a different internal standard.

I have attempted the experiment twice using this method. Each attempt was repeated for 3 sets of data, each containing 6 standards ranging from 0 to 0.15% and 6 analytes.

The first attempt has extremely large peaks, where the internal standard should have a peak area of about 0.2 mine are around 15. And the main analyte, while visible is connected at the edge of the larger peak which has likely caused some error. The data still behaves linearly as i would expect it to, if with clear issues. Due to booking errors, this attempt had to be analysed out of hours by the lab staff rather than myself.

the second set was only handled by myself and is much less coherent. peaks are sitting anywhere between 28 and 41, with none of them matching one another between sets. I cannot begin to guess which peak is which to even begin calculations. The total run time for this set was lowered from 10 minutes to two minutes.

Mainly i would like advice on:

A good part of my discussion is basically "how it went wrong", which is only base guesses on my part. Are there any links or keywords/ phrases about chromatography anyone can suggest so i can learn more about it?

I would like to get the experiment to sound positive, it is one thing to reword around unexpected but valid results but another around a potentially messed up experimental. I cannot see anything positive that i can reword the dissertation around.

so far i can use the first set of experiments and discuss how the current method doesn't suit what i was trying to do without further modification and use my calculation to back it up. How would i add the unreliable set to this? all i can think of is that A 2 minute run time just isn't sufficient and that some organic compounds stuck to the column causing contamination.

Any possible help would be appreciated thank you.

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    Did you ask your supervisor? – astronat May 4 at 8:40
  • I did, i get some minor advice before being told that i should have started experiments earlier. I agree but it isn't very useful currently. – S.M.Dyke May 4 at 19:33