When analyzing a standard 4 ppm phenol solution in MeOH by LCMS, why do I see only an m/z of 241.2, not 95 (M+H) as expected?

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Eef Dirksen

Hi,

Although I'm not sure what the compound is you're detecting at m/z 241.2, it seems somewhat illogical to analyze phenol using LC-ESI-MS in positive ion mode, given the apparent absence of proton affinity in the molecule?

Have you tried using negative mode?

Darcey Wayment

Hi Eef,

Thanks for your reply. I have not yet tried negative mode. I will try it.