AssayIndex
Cross-section

SS-31 (Elamipretide) impurity profile

Every named species the index has reported alongside SS-31 (Elamipretide), 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.

124 recordsmedian 99.53 %spec 98.5 %
Median total impurities 0.46% n=124
Median largest single 0.27% n=124
Worst single observed 1.59% n=124
Named species observed 4 / 4 n=4
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
[D-Arg1]-epimer-0.18mass-identical93%0.111.27
acetyl adduct (+42 Da)+0.54+42.01189%0.101.59
des-Dmt (−193 Da)-0.72-193.11087%0.100.58
C-terminal free acid (+1 Da)+0.20+0.98485%0.121.07

[D-Arg1]-epimer

Retention offset from the main peak
-0.18 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
115 of 124 records (93 %)
Level when reported
median 0.11 %, max 1.27 %
How it separates
Chromatography only. A gradient long enough to separate it; no mass spectrometer of any resolution will.

acetyl adduct (+42 Da)

Retention offset from the main peak
+0.54 min on RG-2
Mass difference
+42.011 Da
Reported in
110 of 124 records (89 %)
Level when reported
median 0.10 %, max 1.59 %
How it separates
Baseline-resolved on the reference method.

des-Dmt (−193 Da)

Retention offset from the main peak
-0.72 min on RG-2
Mass difference
-193.110 Da
Reported in
108 of 124 records (87 %)
Level when reported
median 0.10 %, max 0.58 %
How it separates
Baseline-resolved on the reference method.

C-terminal free acid (+1 Da)

Retention offset from the main peak
+0.20 min on RG-2
Mass difference
+0.984 Da
Reported in
106 of 124 records (85 %)
Level when reported
median 0.12 %, max 1.07 %
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.

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.

  • C-terminal amide hydrolysis
  • epimerisation at Arg1 under prolonged basic coupling