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Need more info... but a guess.... impurities are in the solvent you are using?I ran a series (9) of reference stanards acrossing 100 times concentration range (40-4000ug/mL) on a HS-GC/FID. It was found that the 5 impurity peak areas remianed almost unchanged while the target peak aears increased reasonably proportional (R2=0.9995) with the concentration increasing in each level. Please help to explain why!
The HS solvent was purified water which was a "Blank" shot too. There was no any impurity peaks in this blank. Any other info would you need pls? Thanks!Need more info... but a guess.... impurities are in the solvent you are using?I ran a series (9) of reference stanards acrossing 100 times concentration range (40-4000ug/mL) on a HS-GC/FID. It was found that the 5 impurity peak areas remianed almost unchanged while the target peak aears increased reasonably proportional (R2=0.9995) with the concentration increasing in each level. Please help to explain why!
- Karen
No, it was a consequtive run, there was no stop until the completion.If the system sits idle overnight with no runs, is your contamination higher on the first run of the day?
Very good questions and guesses. We are going to look into them.Was the blank prepared at the same time as the standards? or at a different time.
The blank removes the possibility that the system produced the peaks.
My guess is the atmosphere or the vials were contaminated with the peaks you have found.
As I have seen 'pizza' peaks and 'aftershave' peaks in analyses I have performed, I am always amazed how sensitive HS analysis can be.
best wishes,
Rod