AssayIndex
Cross-section

Kisspeptin-10 impurity profile

Every named species the index has reported alongside Kisspeptin-10, how often, at what level, and what its presence implies about the synthesis or the handling. Reporting threshold is 0.05 % area; anything below it is invisible to this page and is silently added to the main peak.

70 recordsmedian 99.27 %spec 98.5 %
Median total impurities 0.73% n=70
Median largest single 0.41% n=70
Worst single observed 1.29% n=70
Named species observed 4 / 4 n=4
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
des-Tyr (−163 Da)-0.56-163.06393%0.160.69
C-terminal free acid (+1 Da)+0.18+0.98493%0.130.46
oxidised Trp (+16 Da)-0.34+15.99586%0.241.29
[D-Trp]-epimer-0.12mass-identical84%0.181.15

des-Tyr (−163 Da)

Retention offset from the main peak
-0.56 min on RG-2
Mass difference
-163.063 Da
Reported in
65 of 70 records (93 %)
Level when reported
median 0.16 %, max 0.69 %
Resolution requirement
Baseline-resolved on the reference method.

C-terminal free acid (+1 Da)

Retention offset from the main peak
+0.18 min on RG-2
Mass difference
+0.984 Da
Reported in
65 of 70 records (93 %)
Level when reported
median 0.13 %, max 0.46 %
Resolution requirement
Close-eluting — resolution below 1.2 is common and the peaks merge on short gradients.

oxidised Trp (+16 Da)

Retention offset from the main peak
-0.34 min on RG-2
Mass difference
+15.995 Da
Reported in
60 of 70 records (86 %)
Level when reported
median 0.24 %, max 1.29 %
Resolution requirement
Baseline-resolved on the reference method.

[D-Trp]-epimer

Retention offset from the main peak
-0.12 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
59 of 70 records (84 %)
Level when reported
median 0.18 %, max 1.15 %
Resolution requirement
A gradient long enough to separate it. No mass spectrometer will.

Degradation pathways

Degradants are a handling finding rather than a synthesis finding. A lot that shipped clean and arrived oxidised tells you about the courier, not the chemist.

  • Trp oxidation
  • C-terminal amide hydrolysis — the amide is required for activity