What is curtain gas in LC-MS technique?

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Markus Christ Popular answer

Hello Forough,

collision gas is not the same as curtain gas. Collision gas is used in triple quads to create fragmentations through collisions with gas molecules. The curtain gas is generated by a JetStream source (manufacturer: Agilent). In addition to the ESI spray, a curtain of hot nitrogen gas is generated, which encloses the ESI spray like a curtain. This accelerates the evaporation processes and significantly increases the sensitivity during ionization.

Regards Markus

Markus Christ

Hello John, hello Sullivan,

you're right. I got it mixed up with the JetStream source's sheath gas. Maybe this is because in some Agilent applications the terms sheath gas and curtain gas are used in parallel. The way you described it is the correct meaning of curtain gas.

Best regards

Markus

Steven J Symes

John,

I use Waters instrumentation and we have never called it "curtain gas". Waters MS's have something called "cone gas" and now i'm wondering if that's the same thing that all of the Agilent and Sciex people call curtain gas? Anyone know?

Sharad Medhe

Dear Steven

I am using all the three MS sysytem Waters- Vion, AB Sciex- 4000 Qtrap and Agilents MS's . I feel all the cone gas and curtain gas are same and agree with Lee that nitrogen gas used for this that" Ions are moved into the mass spec by electrical attraction while neutral stuff (solvent and other junk) gets blown away with the curtain gas".