Why am I observing cyclohexasiloxanes while running N-hexane in GCMS?

11 January 2024 0 7K Report

I have ran n-hexane (highly pure) in GCMS using DB-5MS (newly installed). I have turned off the solvent delay and i am not able to detect the hexane peak. I am only observing two peaks i.e., Methyl isocyanato, cyclohexasiloxanes.

how can i detect a hexane peak and how to obtain a flat baseline in GC-MS.

I have already made sure that the solvent is highly pure.

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