Long Zhang Usually nitrogem (n2) is used as collision gas, which collides with the analyte ions passing Q1 to form fragments. But the EI ion source also "charges" helium atoms (it's not a charge, since helium is an inert noble gas, but a highly energetic state) and forms metastable helium which can charge other molecules inside the MS, which leads to noise (quite a lot of noise since helium is almost always used as carrier gas). And they found out that adding a helium flow to the N2 collision gas flow eliminates those metastable helium atoms, which reduces background noise.
4:56 what does it mean by N2+He? (lower right corner)
Long Zhang Usually nitrogem (n2) is used as collision gas, which collides with the analyte ions passing Q1 to form fragments. But the EI ion source also "charges" helium atoms (it's not a charge, since helium is an inert noble gas, but a highly energetic state) and forms metastable helium which can charge other molecules inside the MS, which leads to noise (quite a lot of noise since helium is almost always used as carrier gas). And they found out that adding a helium flow to the N2 collision gas flow eliminates those metastable helium atoms, which reduces background noise.
Haha cute. Matrix often > analyte :)
Matrix > Analyte * 10^3 hits it better ;)
Nontheless a great instrument!
I DON'T GET HELIUM QUENCHING
EPIC.
WHY ARE YOU ALL SCREAMING?
DOIN DEM SCANS
SCAN SO HARD