Chromatography Forum

I am trying to determine diethyl phthalate (and other phthalates eventually) by GCMS.
I have run a blank ramp with no injection and got no 149 peaks.
I have inserted the clean syringe needle and got some 149 peaks.
When I manually inject clean hexane (determined by fid on another system) I get 149 peaks too.
The GC-MS system gets more septa particles inside the liner than the fid system.
The GC-MS is Saturn 2000 with 1079 injector.
How do you go about setting up a GC-MS for this tricky analysis?
Do you bake out the phthalates from the septa? Do you use a duckbill?
Any help will be greatfully appreciated.
(I've tried HPLC-UV - too many co-elutions!)
WK

Phthalates contamination have many sources. My suggestion is to keep all plastic and rubber products away from the instrument and samples. This includes laboratory gloves, pipette bulbs, natural rubber vial septa, ect....

Make sure to use a PTFE lined vial septa. You may also want to avoid septa on the autosampler "wash" vials.

Wrap all septa in aluminum foil if necessary.