AssayIndex
Annotator

isotope_cluster

Monoisotopic vs average mass and the error people make at 4 kDa.

first seen 2024-Q40 records submitted300 annotations
Section 1

Contribution

Comments technically on records submitted by others. Annotations are signed and are not moderated for agreement.

Records submitted 0 n=0
Annotations 300 n=300
Median purity submitted suppressed n=0 n<3 — see individual records
Suppliers covered 0 n=0

This handle has submitted no records. Annotators comment on other people's submissions and are not required to submit.

Section 2

Annotations

Signed technical comments on records. The index does not moderate annotations for agreement with its own arithmetic, and several of these disagree with it. Where a handle has made the same point on several records, one instance is shown and the rest are reachable from the records themselves.

AX-2026-043429
The isotope pattern is consistent with the elemental composition of L-Glutathione (reduced). That is a second, independent check on identity and it agrees with the mass.
AX-2026-042002
Identity confirmed and purity at 98.23 %. The two answer different questions — what it is, and how much else is in it — and a record carrying both is the version worth citing.
AX-2026-043541
The isotope pattern is consistent with the elemental composition of GHRP-2. That is a second, independent check on identity and it agrees with the mass.
AX-2026-041867
At this mass the monoisotopic peak may not be the most intense peak in the cluster. Picking the apex instead of the monoisotopic peak produces a systematic positive error of roughly the size flagged here.
AX-2026-041766
The isotope pattern is consistent with the elemental composition of BPC-157. That is a second, independent check on identity and it agrees with the mass.
AX-2026-041271
An orthogonal identity method on the same lot would make this the strongest class of record the index holds. Mass plus retention is already better than most.
AX-2026-042474
The isotope pattern is consistent with the elemental composition of LL-37. That is a second, independent check on identity and it agrees with the mass.
AX-2026-042602
Nothing here rules out a positional isomer with the same formula. Mass cannot; only chromatography can, and the gradient length on this record is the relevant fact for that.
AX-2026-043298
The isotope pattern is consistent with the elemental composition of Liraglutide. That is a second, independent check on identity and it agrees with the mass.
AX-2026-042785
The isotope pattern is consistent with the elemental composition of CJC-1295 (no DAC). That is a second, independent check on identity and it agrees with the mass.
AX-2026-043294
Mass, retention and impurity profile all agree on this record. Three independent constraints pointing the same way is the strongest identity evidence the index publishes.
AX-2026-041606
Identity confirmed, purity 98.03 %, mass balance closed. This record is complete against the index definition of complete and there is nothing outstanding on it.

Showing 12 distinct comments of 300 annotations by this handle.