AssayIndex
Annotator

aspartimide

Aspartimide formation at Asp-Gly and Asp-Ser. The tetrapeptide problem.

first seen 2024-Q20 records submitted112 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 112 n=112
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-2026-041779
Aspartimide formation at an Asp-Gly or Asp-Ser motif shows up as a pair of late-eluting satellites. They are not present above the reporting threshold on this trace.
AX-2026-043372
A pair of satellites either side of the main peak at roughly equal levels is the aspartimide signature. Worth checking the named-impurity table before attributing 3.31 % to coupling efficiency.
AX-2026-043090
A pair of satellites either side of the main peak at roughly equal levels is the aspartimide signature. Worth checking the named-impurity table before attributing 3.54 % to coupling efficiency.
AX-2026-043279
Purity 96.57 %, water 5.82 %, counter-ion 6.47 % TFA. Read together these say the cake is what it claims to be and the chromatographic homogeneity is the limiting property. That narrows the question usefully.
AX-2026-043258
98.95 % on L-Carnosine is below the index specification for the class. The interesting part is the distribution: D-carnosine epimer at 0.51 % is doing most of the work, and that species is a synthesis artefact rather than a degradation product. This is a process observation about lot CPC-2603-G9615, not a storage one.
AX-2026-043364
A pair of satellites either side of the main peak at roughly equal levels is the aspartimide signature. Worth checking the named-impurity table before attributing 2.12 % to coupling efficiency.
AX-2026-043102
A pair of satellites either side of the main peak at roughly equal levels is the aspartimide signature. Worth checking the named-impurity table before attributing 1.30 % to coupling efficiency.
AX-2026-043175
96.95 % on Tirzepatide is below the index specification for the class. The interesting part is the distribution: C20 diacid mono-amide at 1.45 % is doing most of the work, and that species is a synthesis artefact rather than a degradation product. This is a process observation about lot GLBI-2510-N7555, not a storage one.
AX-2026-043026
Purity 98.68 %, water 2.85 %, counter-ion 4.92 % acetate. Read together these say the cake is what it claims to be and the chromatographic homogeneity is the limiting property. That narrows the question usefully.
AX-2026-042299
A pair of satellites either side of the main peak at roughly equal levels is the aspartimide signature. Worth checking the named-impurity table before attributing 1.16 % to coupling efficiency.
AX-2025-019889
The record is published in full, including the impurity table that explains it. A number below specification with a named impurity profile beside it is more useful than a number above specification with nothing beside it.
AX-2025-021121
A pair of satellites either side of the main peak at roughly equal levels is the aspartimide signature. Worth checking the named-impurity table before attributing 1.12 % to coupling efficiency.

Showing 12 distinct comments of 112 annotations by this handle.