DB-5 column in a GC/MS?

[Eluter]

Is it possible to use a DB-5 column rather than a DB-5MS column in a GC/MS or is the background too high?

[Jetjamnong]

I used both DB-5 and DB-5MS in my GC/MS systems, DB-5 is higher backgroud noise than DB-5MS especially m/z 207 and 281 when temperature raise to 250 degree Celsius but it not have any problem when my interesting compounds don't have characteristic ion with 207 and 281.

[AICMM]

Yes, especially if you are not going very hot. If pushing 280 or 290, you will end up cleaning your source more if you choose to use a -5 instead of a -5MS. Is that worth it to you?

Best regards,

AICMM

[01310040231]

There is new version of DB5-MS called DB8270 which has even lower bleed but it cost more.

[Dr Herbert West]

It's important to note that the DB-5 and the DB-5MS are two different stationary phases in that the DB-5MS has phenyl inserted into the siloxane backbone to lower the bleed. That changes the selectivity of the column, which may or may not be noticeable to you depending on the compounds you're trying to analyze. Both columns can be used up to 325/350°C, but the DB-5MS should have a bit lower bleed.

Don't overlook conditioning the column (before installing in the MS source), whatever the stationary phase, as a good way to start with the lowest bleed possible.

[Saba Nazir]

I need to wash DB-5MS column because I havnt a DB-5MS in my stock I am waiting for quotation but in the meanwhile I wanna wash it or clean it so for that I am injecting 1ul DCM on my Method in which Column programing is upto 300 degree celcius and MS is at 230 degree celcius. will it work that I have to run 2-3 samples urgently? actually column was ok only noise was more than normal thats why I wanna do that. kindly help me and guide me plzzz?

Best regards,

[Consumer Products Guy]

If the column is good, use it.

It was my understanding when I was working that when such columns were manufactured and tested, that those that tested with lower background and bleed were separated and sold as MS versions.

I have back-rinsed some bonded phase columns with methylene chloride in my day, then blew them dry with helium. But that takes time and has to be set-up too. So I can't really recommend that if you're in a pinch.

And if you have other nonpolar columns like DB-1 around, maybe those can be used; after all, you'd be confirming identity with the MS detector.

[Saba Nazir]

thanks alot for your kind reply, it is really helpful for me.
best Regards,