Split/Splitless Liners

[Pat Crowley]

Hello,

I am using a Shimadzu 14B GC fitted with a split/splitless focus liner SigmaAldrich No. 2878105-U
(http://www.sigmaaldrich.com/catalog/Pro ... KEY&F=SPEC)

I normally use this in split mode. Can these liners be used in splitless mode or is it better to use a dedicated splitless liner for splitless injections

[Don_Hilton]

While I use a different make of instrumet, I have often used a split/spltless liner for both modes of injection.

The question is really does the liner match what you are injecting. A liner with wool is great for analyzing "dirty" samples. But if you are analyzing compunds that are particularly sensitive to activity in the inlet - the wool may hurt your sensitivity.

When starting to analyze samples that differed with what I have been analyzing before, I open the vendor catalogs and look at what liners they have and what they reccomend they be used for.

So, If you will tell what you are wanting to inject, perhaps you can get a more specific answer.

[Pat Crowley]

Thanks for the reply. The solution I am injecting is a mixture of phenols at about 2 ppm level in Ethyl Acetate. ( Phenol, methylphenols, and chlorophenols.) I have injected this mixture and it works with this wool packed liner. I guess my question is does the designation "split/splitless" mean that this liner is as good for splitless injection as one specifically labelled for splitless injection.

[Peter Apps]

If you are injecting 1 ul, that contains 2 ng of phenols at 2 ppm. With these quantities the peak shape and area are vulnerable to adsorptive activity, such as can arise with glass wool packing. You might get better results with an empty splitless liner, but vapourizing inlets are such a can of worms that the only way to be sure is to actually do the comparison using real samples.

Peter

[Don_Hilton]

I have always taken the term split/splitless in the designation for a liner as meaning that it can be used for either. If I recall correctly, back in the days of the printed catalogs you would find the liner listed on the page for split injection techniques as well as the page for splitless injection techniques. (Now I check the box requesting a printed catalog and get to use the web site while I wait - and for one of my favorite catalogs, this has been over a year with multiple requests...)