Hi all,

I'm looking for some input on the analysis of a dianhydride. The specific analyte is pyromellitic dianhydride (PMDA). Currently, I can detect the analyte at high levels by GC/FID, GC/MS (SIM) or LC/UV (220nm) but I need to push my instrument detection limit down or concentrate the sample. I can see approximately 1ppm by GC and 10ppm by UV.

I am having a hard time finding any references that are for the analysis of anhydrides in aqueous solutions. Rather, I am finding anhydrides used for the analysis of other compounds (sugars, etc.).

There is mention that the PMDA will decompose in water, however I am able to reproduce a UV/VIS scan of the PMDA in ACN and water. I have not tried to heat the water to determine degradation, yet.

I am open to any ideas where a concentration can be employed, SPE, L/L partitioning. Or, if a derivatization is possible, a lower instrument detection limit should be apparent.

Any input is appreciated. Thanks.