Tirzepatide impurity profile
Every named species the index has reported alongside Tirzepatide, 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
1.45%
n=750
Median largest single
0.76%
n=750
Worst single observed
2.30%
n=750
Named species observed
8 / 8
n=8
| Named species | ΔRT (min) | Δ mass (Da) | Seen in | Median % area | Max % area |
|---|---|---|---|---|---|
| [D-Aib13]-diastereomer | -0.19 | mass-identical | 86% | 0.17 | 2.30 |
| des-Aib2 analogue | -0.35 | -85.053 | 81% | 0.13 | 1.55 |
| Met(O) sulfoxide (+16 Da) | -0.74 | +15.995 | 72% | 0.08 | 1.64 |
| C20 diacid mono-amide | +1.62 | +0.984 | 72% | 0.12 | 1.62 |
| des-Gly deletion (−57 Da) | -0.61 | -57.021 | 70% | 0.12 | 1.90 |
| truncated (3-39) | -1.48 | -222.112 | 68% | 0.18 | 1.81 |
| trifluoroacetyl adduct (+96 Da) | +0.93 | +95.982 | 61% | 0.08 | 2.17 |
| tirzepatide dimer | +3.98 | +4810.410 | 39% | 0.05 | 1.53 |
[D-Aib13]-diastereomer
- Retention offset from the main peak
- -0.19 min on RG-2
- Mass difference
- mass-identical — chromatography only
- Reported in
- 644 of 750 records (86 %)
- Level when reported
- median 0.17 %, max 2.30 %
- How it separates
- Chromatography only. A gradient long enough to separate it; no mass spectrometer of any resolution will.
des-Aib2 analogue
- Retention offset from the main peak
- -0.35 min on RG-2
- Mass difference
- -85.053 Da
- Reported in
- 608 of 750 records (81 %)
- Level when reported
- median 0.13 %, max 1.55 %
- How it separates
- Baseline-resolved on the reference method.
Met(O) sulfoxide (+16 Da)
- Retention offset from the main peak
- -0.74 min on RG-2
- Mass difference
- +15.995 Da
- Reported in
- 543 of 750 records (72 %)
- Level when reported
- median 0.08 %, max 1.64 %
- How it separates
- Baseline-resolved on the reference method.
C20 diacid mono-amide
- Retention offset from the main peak
- +1.62 min on RG-2
- Mass difference
- +0.984 Da
- Reported in
- 541 of 750 records (72 %)
- Level when reported
- median 0.12 %, max 1.62 %
- How it separates
- Baseline-resolved on the reference method.
des-Gly deletion (−57 Da)
- Retention offset from the main peak
- -0.61 min on RG-2
- Mass difference
- -57.021 Da
- Reported in
- 523 of 750 records (70 %)
- Level when reported
- median 0.12 %, max 1.90 %
- How it separates
- Baseline-resolved on the reference method.
truncated (3-39)
- Retention offset from the main peak
- -1.48 min on RG-2
- Mass difference
- -222.112 Da
- Reported in
- 509 of 750 records (68 %)
- Level when reported
- median 0.18 %, max 1.81 %
- How it separates
- Baseline-resolved on the reference method.
trifluoroacetyl adduct (+96 Da)
- Retention offset from the main peak
- +0.93 min on RG-2
- Mass difference
- +95.982 Da
- Reported in
- 456 of 750 records (61 %)
- Level when reported
- median 0.08 %, max 2.17 %
- How it separates
- Baseline-resolved on the reference method.
tirzepatide dimer
- Retention offset from the main peak
- +3.98 min on RG-2
- Mass difference
- +4810.410 Da
- Reported in
- 294 of 750 records (39 %)
- Level when reported
- median 0.05 %, max 1.53 %
- 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.
- Met14 oxidation on exposure to peroxide-bearing excipients or air-saturated diluent
- aspartimide formation at the Asp-Gly motif during synthesis, carried into the lot
- slow deamidation of Asn in reconstituted material stored above 8 °C