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.

97 recordsmedian 99.42 %spec 98.5 %
Median total impurities 0.58% n=97
Median largest single 0.33% n=97
Worst single observed 1.89% n=97
Named species observed 4 / 4 n=4
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
C-terminal free acid (+1 Da)+0.20+0.98495%0.081.89
des-Dmt (−193 Da)-0.72-193.11088%0.111.88
[D-Arg1]-epimer-0.18mass-identical79%0.131.34
acetyl adduct (+42 Da)+0.54+42.01178%0.241.31

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
92 of 97 records (95 %)
Level when reported
median 0.08 %, max 1.89 %
Resolution requirement
Close-eluting — resolution below 1.2 is common and the peaks merge on short gradients.

des-Dmt (−193 Da)

Retention offset from the main peak
-0.72 min on RG-2
Mass difference
-193.110 Da
Reported in
85 of 97 records (88 %)
Level when reported
median 0.11 %, max 1.88 %
Resolution requirement
Baseline-resolved on the reference method.

[D-Arg1]-epimer

Retention offset from the main peak
-0.18 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
77 of 97 records (79 %)
Level when reported
median 0.13 %, max 1.34 %
Resolution requirement
A gradient long enough to separate it. No mass spectrometer will.

acetyl adduct (+42 Da)

Retention offset from the main peak
+0.54 min on RG-2
Mass difference
+42.011 Da
Reported in
76 of 97 records (78 %)
Level when reported
median 0.24 %, max 1.31 %
Resolution requirement
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.

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