rb6banjo wrote:
We bought a TD unit earlier this year. I've been a devout SPME user for years up until this point. I am discovering that the "extra capacity" can be a bit of a curse. It seems that you have to live with higher backgrounds. I've been dabbling with extra pdms sampling devices (no names) and I believe I'm on the right track BUT I've come to the realization that there will always be higher backgrounds as a result of using these devices. SPME has such a small mass, it's easy to clean the fibers to nearly zero extraneous emissions. You might have limited capacity with the SPME fibers. They do have amazing capacity for such small-mass devices!
Same with Tenax traps. I don't know that you can ever get them to zero residuals. It's like any technique, you just have to know what it will do for you and what it won't.
Looks like a PDMS device that's larger than SPME. Something along the lines of the Gerstel Twister but with different sample handling? Always interesting to see new products.
As far as high backgrounds, if you get the chance, setup thermal desorption on a MS/MS system or high resolution TOF. Both cases are real eye openers. MS/MS takes that high baseline and drops it to zero except for your target compounds and allows you to crank up the multiplier. HRTOF lets you look at everything and then pull out your target compounds using mass resolution to eliminate background. Both have their uses.