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Sciex mass spec support

Posted: Mon Jun 24, 2019 8:36 pm
by ThorpeSc1
If you need help with Sciex mass specs feel free to post in here. I'm an independent service engineer, factory trained on triple quads and qtraps, with 12years experience. (UK based).

Happy to give out some pointers if you are having troubles

Re: Sciex mass spec support

Posted: Wed Mar 25, 2020 2:47 pm
by Sagwa
Hi there and I'm so happy I found your post :)

I posted this today to the LC-MS board and I think you might be just the right person to answer my questions:

I've been using LC-MS for some time now, but unfortunately, I have no mentor to ask all the questions in mind so I will really appreciate your expertise.
My main concern is the hardware and keeping it clean and undamaged. There have been a few gas shortages and I would love to know the best practices for a situation of this kind.

The instrument in question is QTRAP. I've been told that if there's no gas flow I should monitor the system vacuum and if it falls below a certain level there's a risk of instrument contamination.

Why would the system vacuum keep increasing over time if there is no gas flow? The normal operating pressure of the instrument is 2x10^-5 Torr (system running) / 0.6x10^-5 Torr (system idle). I assume the decrease in vacuum when running is caused by the increased gas flow (compared to idle)?

Now, the normal (idle) pressure being 0,6x10^-5 Torr, what would be a harmfully low pressure for this system that could cause contamination?
How long, approximately, is it safe to have the instrument with full vacuum in case of gas shortage? The LC would be detached at this point, of course.

Re: Sciex mass spec support

Posted: Sat May 30, 2020 12:06 am
by Edwin
Is this a 2000 Qtrap instrument you are talking about ?

Re: Sciex mass spec support

Posted: Wed Jan 24, 2024 5:01 pm
by masspecchins
Hi . I work in a lab that does drug monitoring and so toxicology test on urine samples. We use Sciex MD4500 .What are the waste gases that are produced from the exhaust in this case? We just learned that the exhaust tube was just going into the drop ceiling and not really outside. This would mean that the air could have been crawling back into the lab rooms. Our sample diluent is methanol and water. I cant find out how the exhaust air would cause any long health hazard. Thanks in advance for your help.