AssayIndex
Cross-section

BPC-157 impurity profile

Every named species the index has reported alongside BPC-157, 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.

591 recordsmedian 99.15 %spec 98.0 %
Median total impurities 0.85% n=591
Median largest single 0.45% n=591
Worst single observed 1.62% n=591
Named species observed 6 / 6 n=6
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
des-Gly truncate (−57 Da)-0.34-57.02184%0.131.32
[D-Val]-diastereomer-0.14mass-identical80%0.101.62
pyroglutamate cyclisation (−17 Da)+0.31-17.02779%0.091.39
acetylated N-terminus (+42 Da)+0.48+42.01178%0.091.56
truncated (1-12)-0.96-285.13272%0.051.53
BPC-157 arginine-salt artefact-0.55mass-identical66%0.041.52

des-Gly truncate (−57 Da)

Retention offset from the main peak
-0.34 min on RG-2
Mass difference
-57.021 Da
Reported in
495 of 591 records (84 %)
Level when reported
median 0.13 %, max 1.32 %
Resolution requirement
Baseline-resolved on the reference method.

[D-Val]-diastereomer

Retention offset from the main peak
-0.14 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
470 of 591 records (80 %)
Level when reported
median 0.10 %, max 1.62 %
Resolution requirement
A gradient long enough to separate it. No mass spectrometer will.

pyroglutamate cyclisation (−17 Da)

Retention offset from the main peak
+0.31 min on RG-2
Mass difference
-17.027 Da
Reported in
465 of 591 records (79 %)
Level when reported
median 0.09 %, max 1.39 %
Resolution requirement
Baseline-resolved on the reference method.

acetylated N-terminus (+42 Da)

Retention offset from the main peak
+0.48 min on RG-2
Mass difference
+42.011 Da
Reported in
459 of 591 records (78 %)
Level when reported
median 0.09 %, max 1.56 %
Resolution requirement
Baseline-resolved on the reference method.

truncated (1-12)

Retention offset from the main peak
-0.96 min on RG-2
Mass difference
-285.132 Da
Reported in
428 of 591 records (72 %)
Level when reported
median 0.05 %, max 1.53 %
Resolution requirement
Baseline-resolved on the reference method.

BPC-157 arginine-salt artefact

Retention offset from the main peak
-0.55 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
388 of 591 records (66 %)
Level when reported
median 0.04 %, max 1.52 %
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.

  • N-terminal pyroglutamate formation on storage of the free-base form
  • Asp-Gly aspartimide during synthesis
  • oxidative degradation is negligible — no Met, no Cys, no Trp