Headspace Sample Preparation

[a.r.spencer]

My laboratory is expanding and I have to opportunity to design my new space. We currently run a residual solvnets method similar to USP <467> where the sample is dissolved in DMSO. We have had problems with carryover in the past. We showed experimentally that the DMSO will pick up any solvents that are in the area. We currently have to clear out our laboratory when preparing headspace vials for this analysis. I am looking for ideas for the preparation of headspace vials in a solvent free environment. I am currently looking into glove boxes, but was wondering what others are doing/using.

Thanks for your input!

[chromatographer1]

I understand your concern.

I used to see methanol and acetonitrile from the LCs on my floor of my building. Toluene from the diesel truck exhaust from the parking lot.

Purging a box was never necessary. I simply prepared my standard additions using volumetric flasks and a digital balance. I had my solvents in their own 10mL flasks (stoppered of course) or capped vials.

Usually the DMSO showed volatile decomposition peaks after it had picked up water from the air, not from solvents in the air. DMDS DMS etc.

If you see solvents from the lab air when you handle DMSO in this manner then you are not breathing safe air.

Don't use 4L bottles of DMSO. Buy 250mL bottles or smaller. Consume it before it goes bad from water contamination.

Good luck,

Rod