Two questions to users of triple quads of Applied Biosystems

[chern_es]

What kind of nitrogen to you use for your MS/MS system?
Do you use a nitrogen generator and - if yes - what model?

Thank you in advance.

[yangz00g]

Should you say a " Thank you" first? thanks

[chern_es]

Dear yangz00g,
Thank you for your comment. Sorry for some hurry.
Are you a user of ABI's triple quad?

[sassman]

We have a large (260L) liquid nitrogen dewar for our API 3000. It has wheels, and we fill it downstairs from a big outdoor tank. With the MS going 24h per day, it lasts us about 4 days. I believe liquid N2 is the way to go since the purity is excellent and a dewar will last much longer than a gas cylinder and doesn't have the purity and maintenance issues of a gas generator.

[bdebruler]

I agree with sassman about the dewar. Companies that supply gas cylinders will also usually have LN2 dewars, and will swap them out as needed. A nice setup includes an automatic changeover valve with a backup N2 cylinder in case you run out faster than you expect, or don't want to take your instrument offline for a dewar swap.

[chern_es]

We have a large (260L) liquid nitrogen dewar for our API 3000. It has wheels, and we fill it downstairs from a big outdoor tank. With the MS going 24h per day, it lasts us about 4 days. I believe liquid N2 is the way to go since the purity is excellent and a dewar will last much longer than a gas cylinder and doesn't have the purity and maintenance issues of a gas generator.

Actually, I like the idea of using liquid N2, but my chief does not. We have two ABI 2000 systems, and this means that we would have to exchange the dewar too often (each 2 days), and it seems to be too expensive. Please, give me some more arguments in favor of liquid N2, if you can.

[chern_es]

A nice setup includes an automatic changeover valve with a backup N2 cylinder in case you run out faster than you expect, or don't want to take your instrument offline for a dewar swap.

Dear Bdebruler, could you please explain in more detail such setup or give some link to look at it?
Do I understand right that you just connect a Dewar directly to MS, and you have a valve that switches from a Dewar to an N2 tank when you exchange a Dewar? A pressure of N2 from Dewar is enough for MS and you don't use any additional devices to increase the pressure?

[Kostas Petritis]

You'll probably find the following link helpful...

http://www.labgasgenerators.com/news/7

[yangz00g]

I have API5000 with nitrogen supplied by a Parker LCMS5000 gas generator. So far, it works fine except the customer service from Parker is very bad (the worst ever seen). I wish I had bought another brand from another company.

I personally believe that a gas generatror is good as long as you can manage the downtime due to problems associated with gas generator. It can also supply zero air if you use APCI a lot.