acetic acid peaks at very beginning of run...what is causing this?

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bryan4284
bryan4284's picture
acetic acid peaks at very beginning of run...what is causing this?

Hello everyone,

This is my first time reaching out here and I am a beginner with GC/MS.  I was curious, does anyone know what the cause of acetic acid peaks at the beginning of my flavor analysis run would be? contamination during inlet liner or septa replacing? contamination of the injector needle?

A little extra info: I am using a two arm PAL system that ramps from 75-270C over a 9.31 minute run with self packed inlet liners.

Any assistance would be greatly appreciated, thanks in advance.

Dr. Analytical
Dr. Analytical's picture
Bryan:

Bryan:
First, please post some more information about your system - GC manufacturer, column, etc.  What are your liners packed with?  Is this split or splitless injection, or headspace or ?

Next, are you sure that these peaks are acetic acid?  Have you compared the fragmentation pattern with a library standard?  (You should always check the match manually whenever you have an unusual result.  Never trust the computer!)

In general, acetic acid could be produced by hydrolysis of acetate esters, which are common components in various flavor combinations.  Contamination from the system is more rare.