552.3 inlet degradation of analytes
Posted: Wed Feb 22, 2012 10:39 pm
by montucky1
has anyone run into analyte degradation in the inlet of your GC? Had the method optimized for a quick runtime, but there were a few caveats and the SOP was getting a little difficult so i went back to the method suggested oven program and gained MCAA and lost DCAA... Any ideas?
Re: 552.3 inlet degradation of analytes
Posted: Fri Apr 06, 2012 9:20 am
by jdezeeuw
This happens many times. With pesticides, carbamates, flame retardants..
If decomposition happens in teh LINER you need to eliminate Glass wool (take a double gooseneck or a cyclosplitter), Use LOWER injection port temperatures (using splitless injection you can us eMUCH lower temperatures as you inject during long time), or use PTV or even better: cold -on-column.
If decomposition happens in the column:(you can see by peak-shape): Make sure we minimize elution temperatures by:
Using Highest flow rate , Flow programming, columns with THIN films, SHORT length and preferrable H2 as carrier gas.
For instance for the BFR's we developed a special "fast" columns based on EPA1614.
rgsd
jaap de zeeuw, Restek corporation