Glucagon impurity profile
Every named species the index has reported alongside Glucagon, 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.
Median total impurities
1.23%
n=10
Median largest single
0.64%
n=10
Worst single observed
1.11%
n=10
Named species observed
4 / 4
n=4
| Named species | ΔRT (min) | Δ mass (Da) | Seen in | Median % area | Max % area |
|---|---|---|---|---|---|
| Met27 sulfoxide (+16 Da) | -0.79 | +15.995 | 100% | 0.23 | 0.71 |
| deamidated Asn28 (+1 Da) | -0.36 | +0.984 | 100% | 0.39 | 1.11 |
| des-His1 (−137 Da) | -0.94 | -137.059 | 100% | 0.08 | 0.26 |
| glucagon fibril-derived aggregate | +2.61 | mass-identical | 90% | 0.27 | 1.08 |
Met27 sulfoxide (+16 Da)
- Retention offset from the main peak
- -0.79 min on RG-2
- Mass difference
- +15.995 Da
- Reported in
- 10 of 10 records (100 %)
- Level when reported
- median 0.23 %, max 0.71 %
- Resolution requirement
- Baseline-resolved on the reference method.
deamidated Asn28 (+1 Da)
- Retention offset from the main peak
- -0.36 min on RG-2
- Mass difference
- +0.984 Da
- Reported in
- 10 of 10 records (100 %)
- Level when reported
- median 0.39 %, max 1.11 %
- Resolution requirement
- Baseline-resolved on the reference method.
des-His1 (−137 Da)
- Retention offset from the main peak
- -0.94 min on RG-2
- Mass difference
- -137.059 Da
- Reported in
- 10 of 10 records (100 %)
- Level when reported
- median 0.08 %, max 0.26 %
- Resolution requirement
- Baseline-resolved on the reference method.
glucagon fibril-derived aggregate
- Retention offset from the main peak
- +2.61 min on RG-2
- Mass difference
- mass-identical — chromatography only
- Reported in
- 9 of 10 records (90 %)
- Level when reported
- median 0.27 %, max 1.08 %
- 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.
- fibrillation within hours at acidic pH and room temperature — the classic instability
- Met27 oxidation
- Asn28 deamidation