Brand new Xevo G2-S Q-TOF data...looks messy
Posted: Sat Jan 31, 2015 9:20 pm
Our lab just got a brand new Xevo G2-S Q-TOF and the machine is probably being used to 1% of it's true ability.
Anyway, I've always noticed that TOF total ion chromatograms just never look as nice as triple quad TIC's. When I run a sample on the triple quad, each peak generally corresponds to a particular m/z and the smaller fragments. The Q-TOF data is just all over the place. It's made figuring out what's in a mixed sample nearly impossible. I ran a pretty standard acylation reaction using Meldrum's acid and Heptanoyl chloride, and literature (and my TLC) gave a high recovery and purity with a m/z of the compound +Na.
I search out all possible combinations of +H and +Na and I just see nothing.
Even a blank is filled with noise, and yes everything has been cleaned 10x over.
Caffeine as a standard looks fine, the UV is shark, the TIC is a rather tall and kind of broad peak, but the 195 m/z is the only one.
Reaction mixtures are just noisy and seem to have so many ions upstream and downstream when the peaks mass spectrum is selected.
Is that just the nature of a Q-TOF? Can switching to centroid from continuum have any effect?
It sucks having this new toy and just seeing so much noise
Anyway, I've always noticed that TOF total ion chromatograms just never look as nice as triple quad TIC's. When I run a sample on the triple quad, each peak generally corresponds to a particular m/z and the smaller fragments. The Q-TOF data is just all over the place. It's made figuring out what's in a mixed sample nearly impossible. I ran a pretty standard acylation reaction using Meldrum's acid and Heptanoyl chloride, and literature (and my TLC) gave a high recovery and purity with a m/z of the compound +Na.
I search out all possible combinations of +H and +Na and I just see nothing.
Even a blank is filled with noise, and yes everything has been cleaned 10x over.
Caffeine as a standard looks fine, the UV is shark, the TIC is a rather tall and kind of broad peak, but the 195 m/z is the only one.
Reaction mixtures are just noisy and seem to have so many ions upstream and downstream when the peaks mass spectrum is selected.
Is that just the nature of a Q-TOF? Can switching to centroid from continuum have any effect?
It sucks having this new toy and just seeing so much noise