During GC-MS analysis of green tea extract (Camellia sinensis var. assamica).there are multiple compounds detected per peak So which one will be the compound corresponding to the peak.Are all the compounds are said to be present in the single peak (whichever is detected).do i need to add all the compound names for each peak ?
Dear Rahan,
The more complex your sample, the larger the probability of multiple substances in the same peak.
You can choose an ion that you think is exclusive to your compound among the set of substances in that peak to see the format of the peak of your compound. If you still have other substances with the same ion fragment the peak will not be symmetrical and you may need to find a better fragment.
You can test other ion fragments that you believe belong to your compound exclusively to find out the true format of the peak of your compound. After a few attempts, I think you will have a good idea of the format of the peak of your compound.
Are you absolutely sure that you have a goo0d separation between different substances. Sometimes you have isomers which are very difficult to separate. Is this your case? Are you using a proper GC column? You can have more than one compound in a peak, but usually this means you are not using a proper column or you have to use a different column temperature program and/or different flow rate or a most properly GC columns (polar, non-polar or medium polarity). I suggest you can see among all of the GC parameters in order to try to separate those compounds.
If you are using the Mo mass alone to predict the composition, within an allowable mass error, you can use the isotopic ratio to better predict which is the mostly likely composition. While some peak identity software does this with the ratio of the first isotope, I found that it is better to perform an isotopic vector angle approach using the abundances of all isotopes. (re: Method Isotopic Vector Angle Analysis in Mass Spectrometry v2
).- Badges
- Science topic
- Similar topics
- Filing