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compressed air for nebulizer/LCMS Ionspray?
Posted: Sat Jun 05, 2010 5:46 am
by Alp
I have used nitrogen in the past, but I am considering switching to compressed air as the nebulizer gas. The instrument manuals I have seem to indicate this is acceptable as long as it is "zero air".
Are there strong risks to using air as nebulizer gas when using flammable mobile phases (alcohols, acetonitrile) with any percentage of water, or with 100% organic? Can a spark from the high voltage ionspray cause ignition?
Alp
Posted: Sat Jun 05, 2010 8:38 am
by bhuvfe
Alp,
Maybe it can work if you use nanoESI or only aqueous mobile phases.
But I wouldn't dare to try. At the 1st accident I would be buried in paperwork
for months by my company safety people.
Consider also that if your analyte is prone to oxidation using compressed air and some temperature (250-300 C) will not help your analysis (or if helps maybe you can publish as oxidative-ESI
).
bhuvfe
Posted: Sun Jun 06, 2010 3:25 am
by Alp
Interesting point about the possibility of oxidation.
The ion source of one of our instruments is open to the atmosphere, so I imagine there should be plenty of oxygen present there whether I use N2 or Air.
Anyone ever use Air for nebulizer gas?
Is it safe?
Posted: Sun Jun 06, 2010 3:41 am
by haiedc
Interesting point about the possibility of oxidation.
The ion source of one of our instruments is open to the atmosphere, so I imagine there should be plenty of oxygen present there whether I use N2 or Air.
Anyone ever use Air for nebulizer gas?
Is it safe?
Even it is open to the atmosphere, I still think the abundant nitrogen should be around a lot if you use N2 as nebulizer gas.
Anyway, if you tried compressed air, please post the results.
Posted: Sun Jun 06, 2010 9:11 am
by bhuvfe
Please give a look at page 26 of this document.
http://www.chem.agilent.com/Library/use ... 0Guide.pdf
or page 7 of this one.
http://www.waters.com/webassets/cms/sup ... 7902rb.pdf
Is there really nothing similar on the manual of your ABI?
Posted: Tue Jun 15, 2010 12:17 am
by Alp
Thank you for the reply,
I found the documents quite interesting.
Both systems specify N2 for Nebulizer.
Quite different from the API 3000 guide which states Air or N2 can be used for nebulizer gas.
Thank you.
Alp
Posted: Tue Jun 15, 2010 3:14 pm
by Ron
There is a good possibility that Agilent and Waters are being very conservative to avoid any possible liability, even though the probability of an explosion is very low. I also think part of the reason for the Waters and Agilent recommendation is fear of contamination if house air is used. Zero air is a synthetic air blended from purified nitrogen and oxygen, and is much higher purity than air from a compressor. If you calculate the cost of using zero air, I suspect that nitrogen from a Dewar is much less expensive.
Posted: Fri Jul 02, 2010 5:52 am
by Alp
In answer to my own question....
The varian 320-MS LCMS can use air as the nebuliser gas (as specified in their specsheet.
By the way, if I did not mention in my original post, the idea was to filter the air (to zero air spec) using a sub micron filter and a charcol trap (for and residual oil vapours from an oilfree compressor).
I have decided to use compressed air, and opt to switch to N2 from time to time to see if there is significant oxidation of analyte going on.
Alp
Thanks for the feedback!
Posted: Mon Jul 05, 2010 4:18 am
by netsking
In answer to my own question....
The varian 320-MS LCMS can use air as the nebuliser gas (as specified in their specsheet.
By the way, if I did not mention in my original post, the idea was to filter the air (to zero air spec) using a sub micron filter and a charcol trap (for and residual oil vapours from an oilfree compressor).
I have decided to use compressed air, and opt to switch to N2 from time to time to see if there is significant oxidation of analyte going on.
Alp
Thanks for the feedback!
We are waiting for your results.