Intersection · Analytics × charge states

Analytics topics tagged charge states

Topics in Analytics carrying the tag charge states. Multiply charged ions in electrospray and how to read them.

22 topics

Topic	Participants	Replies	Views	Activity
Isotope patterns and why the monoisotopic peak is not the tallest — does this still hold? charge states counter-ion content high-resolution MS mass error (ppm) Solved Isotope patterns and why the monoisotopic peak is not the tallest — does this still hold? — that is the question, and I have not found it answered plainly anywhere I have looked. Asking about Isotope patterns…		2	4.6k	7h
MS/MS sequence confirmation: what it costs and when it is worth it LC-MS MALDI-TOF charge states Solved Pinned MS/MS sequence confirmation: what it costs and when it is worth it — setting out what I have, and where I think it stops being reliable. I would like to understand what this number means before I repeat it…	+2	6	2.7k	1d
Mass error in ppm: the arithmetic and the caveat — a second dataset counter-ion content mass error (ppm) charge states LC-MS Solved On the subject in the title: Mass error in ppm: the arithmetic and the caveat — a second dataset Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked.…	+20	24	1.7k	1d
MS/MS sequence confirmation: what it costs and when it is worth it — what changed since charge states LC-MS MALDI-TOF counter-ion content Closed Posting this under the heading it deserves: MS/MS sequence confirmation: what it costs and when it is worth it — what changed since Everything below is what sits behind that. Two reports on the same lot, and…	+34	39	21k	1mo
[2026 update] Charge states for a 4 kDa peptide, worked through counter-ion content MALDI-TOF high-resolution MS LC-MS On the subject in the title: Charge states for a 4 kDa peptide, worked through Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked. semaglutide has a…	+116	135	31k	3mo
Adducts: sodium, potassium, and the peak you did not expect — does this still hold? high-resolution MS charge states mass error (ppm) MALDI-TOF Solved Asking directly, because I could not find a straight answer: Adducts: sodium, potassium, and the peak you did not expect — does this still hold? Adducts keeps being re-asked here and I think that is because…	+113	119	1.7k	3mo
Second pass at: Counter-ion content and its effect on measured mass mass error (ppm) counter-ion content MALDI-TOF charge states Solved Second pass at: Counter-ion content and its effect on measured mass Writing it up because I had to work it out twice and would rather nobody else did. Something about Counter-ion content does not reconcile…		4	16k	4mo
Second pass at: MALDI versus ESI for a quick identity check MALDI-TOF mass error (ppm) high-resolution MS counter-ion content Solved Second pass at: MALDI versus ESI for a quick identity check Writing it up because I had to work it out twice and would rather nobody else did. Something about MALDI versus ESI does not reconcile and I would…		2	18k	7mo
High-resolution MS on aggregates and what it can see charge states counter-ion content high-resolution MS Posting this under the heading it deserves: High-resolution MS on aggregates and what it can see Everything below is what sits behind that. Something about high-resolution does not reconcile and I would like…	+117	123	6.5k	8mo
What a 2 ppm match establishes, and what it does not high-resolution MS charge states LC-MS MALDI-TOF What a 2 ppm match establishes, and what it does not — that is the question, and I have not found it answered plainly anywhere I have looked. Working through the identity arithmetic and I would like it…	+56	60	5.2k	9mo
Deconvolution of a multiply charged envelope MALDI-TOF charge states mass error (ppm) counter-ion content Closed Deconvolution of a multiply charged envelope — setting out what I have, and where I think it stops being reliable. Working through the identity arithmetic and I would like it checked. tirzepatide has a…		2	63	10mo
Coming back to: Oxidation and deamidation mass shifts, tabulated LC-MS charge states MALDI-TOF high-resolution MS Oxidation and deamidation mass shifts, tabulated — setting out what I have, and where I think it stops being reliable. Reading back through what has been written here about Oxidation and deamidation mass…	+34	38	4.8k	10mo
MALDI versus ESI for a quick identity check high-resolution MS charge states mass error (ppm) MALDI-TOF Closed On the subject in the title: MALDI versus ESI for a quick identity check Working notes rather than a conclusion. I was wrong about MALDI versus ESI in a thread last spring and I would like to correct it…		2	2k	11mo
Distinguishing a deletion sequence by mass alone — the long version high-resolution MS mass error (ppm) charge states MALDI-TOF On the subject in the title: Distinguishing a deletion sequence by mass alone — the long version Working notes rather than a conclusion. A narrow question about Distinguishing a deletion sequence,…	+38	44	60k	11mo
Counter-ion content and its effect on measured mass high-resolution MS charge states MALDI-TOF LC-MS Solved On the subject in the title: Counter-ion content and its effect on measured mass Working notes rather than a conclusion. Something about counter-ion content does not reconcile and I would like a second pair…	+100	108	45k	12mo
Reading an MS report that only gives you a single number counter-ion content mass error (ppm) charge states On the subject in the title: Reading an MS report that only gives you a single number Working notes rather than a conclusion. I would like to understand what this number means before I repeat it anywhere. A…	+100	113	48k	13mo
Oxidation and deamidation mass shifts, tabulated counter-ion content charge states LC-MS mass error (ppm) Solved Posting this under the heading it deserves: Oxidation and deamidation mass shifts, tabulated Everything below is what sits behind that. Oxidation and deamidation mass shifts, and specifically the version of…	+67	76	21k	16mo
Charge states for a 4 kDa peptide, worked through high-resolution MS counter-ion content charge states LC-MS Solved On the subject in the title: Charge states for a 4 kDa peptide, worked through Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked. retatrutide has a…	+124	146	15k	16mo
Why mass spectrometry cannot tell you about an epimer LC-MS mass error (ppm) high-resolution MS charge states Why mass spectrometry cannot tell you about an epimer I have a specific reason for asking rather than idle curiosity, and the context is below. I have spent a fortnight trying to pin mass spectrometry down…	+75	82	4k	17mo
Isotope patterns and why the monoisotopic peak is not the tallest LC-MS MALDI-TOF mass error (ppm) high-resolution MS Isotope patterns and why the monoisotopic peak is not the tallest — setting out what I have, and where I think it stops being reliable. Isotope patterns: what I expected, what I found, and the gap between…	+12	16	7.5k	17mo
Coming back to: Deconvolution of a multiply charged envelope counter-ion content charge states high-resolution MS On the subject in the title: Deconvolution of a multiply charged envelope Working notes rather than a conclusion. Working through the identity arithmetic and I would like it checked. tirzepatide has a…		2	12k	22mo
High-resolution MS on aggregates and what it can see — one year on LC-MS counter-ion content MALDI-TOF charge states Solved High-resolution MS on aggregates and what it can see — one year on Writing it up because I had to work it out twice and would rather nobody else did. A narrow question about High-resolution, deliberately…	+54	58	1.2k	23mo

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