does ms/ms actually prove identity or just make it very likely
#hplc-massspec 2025-04-08
Tuesday18 messages5 participantstimes are UTC
Highlights from this day
- LC_MS_Lena — how do you spot a deletion in a sequence from mass alone truncations show as a mass deficit matching one or more residues. you need the sequence to say which 20:33
- gall_bladder_gav — a warm transit can put a visible degradant peak on a chromatogram. that is what 20 days at ambient does, i think 21:19
- cat_on_the_tray — if the lab reports area percent without stating the wavelength, the number is less useful than it looks 21:21
- cat_on_the_tray — for the archive i have a number at about a third of what i expected, is that a charge state 21:31
- cat_on_the_tray — monoisotopic and average diverge more the bigger the molecule. say which one you are quoting, i think 21:34
do you trust an area percent from a shallow gradient
how do you tell co-elution from a clean single peak
plus sixteen, is that always oxidation
*that should say weekly
how do you spot a deletion in a sequence from mass alone
truncations show as a mass deficit matching one or more residues. you need the sequence to say which
is there any point running a blank if the sample is the question
ask for the trace
plus 0.98 is deamidation
thats the solvent peak
📈2📉6
a warm transit can put a visible degradant peak on a chromatogram. that is what 20 days at ambient does, i think
if the lab reports area percent without stating the wavelength, the number is less useful than it looks
run a blank
plus 16 is oxidation
for the archive i have a number at about a third of what i expected, is that a charge state
monoisotopic and average diverge more the bigger the molecule. say which one you are quoting, i think
oxidation is about plus 15.99 Da and is usually methionine or tryptophan
[edited]whats a plus one dalton shift usually