Chromatography Forum

Can someone advise?

I have standards of 2,4,6-trichlorophenol and 2,4,6-trichloroanisole. The compounds readily andsorb into plastic (may actually pass right through eventually?).
I want to store the 1mg/mL in Acetonitrle solutions in glass vials, but the caps have ptfe liners. I'll bet the compounds will slowly adsorb into the liners. I do not want this to happen.
What should I use?

Alp

Ampoules?

Ampoules....?
You mean, single piece glass bottles with the break off glass tip?
That is what the standards come in from the supplier.

Not going to work for 2 reasons.
I do not have the equipment necessary to fill and seal a glass ampoule.
The container has to be opened and closed several times through the course of a month/year to develop the method, make a range of standards and run samples.
The standards and QC's will have to be stored in the same type of container to prevent loss of analyte to the plastic.

I'd use an aluminum gasket, but I am not sure how this would react with the analytes (I also have to store the bromo equivalents).

Maybe another solution would be to find a source of information on what type of compounds do NOT adsorb to PTFE ???

Alp

Aluminum will probably corrode. Someone makes vials which have a very small diameter opening (sort of a capillary as opening) with maybe a bit more than a square mm teflon seal contact to the content.

Can someone advise?

I have standards of 2,4,6-trichlorophenol and 2,4,6-trichloroanisole. The compounds readily andsorb into plastic (may actually pass right through eventually?).
I want to store the 1mg/mL in Acetonitrle solutions in glass vials, but the caps have ptfe liners. I'll bet the compounds will slowly adsorb into the liners. I do not want this to happen.
What should I use?

Alp

We use ordinary screw cap 10 or 20 ml vials, with a small square of aluminium foil between the lid and the vial. Seems to work OK, but make the standards up every couple of months.

Andy