Interval 113 at LC-Ms

[michelle.zhang]

Dear friends,
I am analyzing a laundry product using LC-MS. It's ES- shows a series of m/z with interval 113. does any one experience this information?
Thank you very much.
Michelle

[Kostas Petritis]

In negative ion mode you have m/z 113 due to TFA. However it's adducts have intervals of 114. Are you positive that you have intervals of 113?

[michelle.zhang]

Sorry, I made wrong information. The interval occured at ES+ type.
The M/z shows 378,491,604,717,830,943...
Is it TFA still?

[Ericz]

Michelle,

What's your mobile phase and sample matrix (if possible to say)? It may help people to dig the source.

Ericz

[Kostas Petritis]

Laundry products have inside surfactants that can give you such m/z distributions. I do not know what kind of surfact does this laundry has inside but I am not surpriced if you see these peaks.

Now maybe I misunderstood your question... Do you mean that the aim of your analysis is these surfactants and your maybe you are asking what type of surfactant this is (I assumed that you are seeking for another compound...).

[michelle.zhang]

Dear Ericz and Kostas,
Thank you for your reply. In fact, I have a samll Masspectrum database for most frequetly used surfactants. But interval of 113 is not in it. So I am not sure if this information from my sample or other sources. The methanol and water were used here only.
If any idea, it's pleasure to wait for.
Michelle

[michelle.zhang]

Kostas,
I prefer that this is not a kind of surfactant. But it is very nice to find what this information is, right?
Michelle

[Ericz]

Have you run a blank (only mobile phase) before and after you tested your sample (prepared in the mobile phase?)?

You may try a MS/MS for one of the mass you observed if you have the instrument capability.