AssayIndex
Cross-section

Oxytocin impurity profile

Every named species the index has reported alongside Oxytocin, 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.

48 recordsmedian 99.81 %spec 98.5 %
Median total impurities 0.18% n=48
Median largest single 0.10% n=48
Worst single observed 0.58% n=48
Named species observed 5 / 5 n=5
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
open-chain (reduced disulfide, +2 Da)-0.52+2.01688%0.060.58
oxytocin dimer (intermolecular disulfide)+2.18+1004.42177%0.060.48
deamidated Gln4 (+1 Da)-0.22+0.98467%0.040.35
Tyr sulfoxide artefact (+16 Da)-0.28+15.99556%0.030.49
des-Gly9 (−57 Da)-0.30-57.02140%0.060.43

open-chain (reduced disulfide, +2 Da)

Retention offset from the main peak
-0.52 min on RG-2
Mass difference
+2.016 Da
Reported in
42 of 48 records (88 %)
Level when reported
median 0.06 %, max 0.58 %
How it separates
Baseline-resolved on the reference method.

oxytocin dimer (intermolecular disulfide)

Retention offset from the main peak
+2.18 min on RG-2
Mass difference
+1004.421 Da
Reported in
37 of 48 records (77 %)
Level when reported
median 0.06 %, max 0.48 %
How it separates
Baseline-resolved on the reference method.

deamidated Gln4 (+1 Da)

Retention offset from the main peak
-0.22 min on RG-2
Mass difference
+0.984 Da
Reported in
32 of 48 records (67 %)
Level when reported
median 0.04 %, max 0.35 %
How it separates
Close-eluting on the reference method, and merged with the main peak on a short gradient. The index prints the resolution figure for such a pair and applies no criterion to it — where the two are not separated, what matters is that the integration convention is stated.

Tyr sulfoxide artefact (+16 Da)

Retention offset from the main peak
-0.28 min on RG-2
Mass difference
+15.995 Da
Reported in
27 of 48 records (56 %)
Level when reported
median 0.03 %, max 0.49 %
How it separates
Close-eluting on the reference method, and merged with the main peak on a short gradient. The index prints the resolution figure for such a pair and applies no criterion to it — where the two are not separated, what matters is that the integration convention is stated.

des-Gly9 (−57 Da)

Retention offset from the main peak
-0.30 min on RG-2
Mass difference
-57.021 Da
Reported in
19 of 48 records (40 %)
Level when reported
median 0.06 %, max 0.43 %
How it separates
Baseline-resolved on the reference method.

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.

  • disulfide reduction then dimerisation
  • Gln4 deamidation — Ph. Eur. limits this specifically