Chromatography Forum

Hi,

I am actually new to gas chromatography and would like your help in troubleshooting this issue. We have been using a Perkin Elmer Autosystem XL GC using FID technology in our lab to measure the amount of 4-bromostyrene in our samples. We use methanol as the internal standard. The GC has worked fine before but is suddenly not giving any peaks for the sample or the methanol.

I haved tried changing the septa and took a look at the flowrates of the air and hydrogen from the manual as well. Increasing the air flowrates does give peaks but they are also too reduced for any proper results. I would really like your help in determining what could the potential issue be in this regards.

Thanks

Wrong setting on the electrometer of the FID. (computer-integrator)

Leak or hardware problem in the injector that dumps sample other than down the column.

How about a before and after chromatogram to compare if you really need assistance?

good luck,

Rod

Check your syringe.

Check for leaks at inlet.