AssayIndex
Cross-section

Retatrutide impurity profile

Every named species the index has reported alongside Retatrutide, 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.

492 recordsmedian 98.37 %spec 96.5 %
Median total impurities 1.63% n=492
Median largest single 0.84% n=492
Worst single observed 2.67% n=492
Named species observed 8 / 8 n=8
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
[D-Aib2]-diastereomer-0.22mass-identical95%0.211.67
des-Aib20 analogue-0.44-85.05386%0.191.52
oxidised Trp (+16 Da)-0.66+15.99574%0.082.28
C18 diacid regioisomer+0.58mass-identical74%0.122.16
truncated (5-39)-1.92-428.20169%0.172.67
aspartimide (−18 Da)+0.71-18.01164%0.081.59
incomplete Fmoc removal (+222 Da)+2.41+222.06858%0.082.15
retatrutide dimer+4.12+4728.48746%0.091.17

[D-Aib2]-diastereomer

Retention offset from the main peak
-0.22 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
467 of 492 records (95 %)
Level when reported
median 0.21 %, max 1.67 %
How it separates
Chromatography only. A gradient long enough to separate it; no mass spectrometer of any resolution will.

des-Aib20 analogue

Retention offset from the main peak
-0.44 min on RG-2
Mass difference
-85.053 Da
Reported in
421 of 492 records (86 %)
Level when reported
median 0.19 %, max 1.52 %
How it separates
Baseline-resolved on the reference method.

oxidised Trp (+16 Da)

Retention offset from the main peak
-0.66 min on RG-2
Mass difference
+15.995 Da
Reported in
364 of 492 records (74 %)
Level when reported
median 0.08 %, max 2.28 %
How it separates
Baseline-resolved on the reference method.

C18 diacid regioisomer

Retention offset from the main peak
+0.58 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
363 of 492 records (74 %)
Level when reported
median 0.12 %, max 2.16 %
How it separates
Chromatography only. A gradient long enough to separate it; no mass spectrometer of any resolution will.

truncated (5-39)

Retention offset from the main peak
-1.92 min on RG-2
Mass difference
-428.201 Da
Reported in
338 of 492 records (69 %)
Level when reported
median 0.17 %, max 2.67 %
How it separates
Baseline-resolved on the reference method.

aspartimide (−18 Da)

Retention offset from the main peak
+0.71 min on RG-2
Mass difference
-18.011 Da
Reported in
315 of 492 records (64 %)
Level when reported
median 0.08 %, max 1.59 %
How it separates
Baseline-resolved on the reference method.

incomplete Fmoc removal (+222 Da)

Retention offset from the main peak
+2.41 min on RG-2
Mass difference
+222.068 Da
Reported in
283 of 492 records (58 %)
Level when reported
median 0.08 %, max 2.15 %
How it separates
Baseline-resolved on the reference method.

retatrutide dimer

Retention offset from the main peak
+4.12 min on RG-2
Mass difference
+4728.487 Da
Reported in
227 of 492 records (46 %)
Level when reported
median 0.09 %, max 1.17 %
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.

  • aspartimide formation and subsequent β-Asp isomerisation at Asp-Ser
  • Trp oxidation under fluorescent light in clear glass
  • aggregation above 2 mg/mL on freeze–thaw