AssayIndex
Cross-section

CJC-1295 (no DAC) impurity profile

Every named species the index has reported alongside CJC-1295 (no DAC), 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.

137 recordsmedian 98.61 %spec 98.0 %
Median total impurities 1.39% n=137
Median largest single 0.69% n=137
Worst single observed 2.00% n=137
Named species observed 5 / 5 n=5
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
des-Tyr1 (−163 Da)-0.54-163.06398%0.321.77
native GRF (1-29) (−59 Da)-0.34-58.99594%0.212.00
deamidated (+1 Da)-0.24+0.98493%0.171.33
truncated (1-24)-1.16-570.29192%0.111.28
acetyl adduct (+42 Da)+0.44+42.01188%0.081.13

des-Tyr1 (−163 Da)

Retention offset from the main peak
-0.54 min on RG-2
Mass difference
-163.063 Da
Reported in
134 of 137 records (98 %)
Level when reported
median 0.32 %, max 1.77 %
Resolution requirement
Baseline-resolved on the reference method.

native GRF (1-29) (−59 Da)

Retention offset from the main peak
-0.34 min on RG-2
Mass difference
-58.995 Da
Reported in
129 of 137 records (94 %)
Level when reported
median 0.21 %, max 2.00 %
Resolution requirement
Baseline-resolved on the reference method.

deamidated (+1 Da)

Retention offset from the main peak
-0.24 min on RG-2
Mass difference
+0.984 Da
Reported in
127 of 137 records (93 %)
Level when reported
median 0.17 %, max 1.33 %
Resolution requirement
Close-eluting — resolution below 1.2 is common and the peaks merge on short gradients.

truncated (1-24)

Retention offset from the main peak
-1.16 min on RG-2
Mass difference
-570.291 Da
Reported in
126 of 137 records (92 %)
Level when reported
median 0.11 %, max 1.28 %
Resolution requirement
Baseline-resolved on the reference method.

acetyl adduct (+42 Da)

Retention offset from the main peak
+0.44 min on RG-2
Mass difference
+42.011 Da
Reported in
121 of 137 records (88 %)
Level when reported
median 0.08 %, max 1.13 %
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.

  • Asn8 deamidation — the reason the D-Ala/Gln/Ala/Leu substitutions exist
  • Asp-Gly aspartimide during synthesis