GHK-Cu impurity profile
Every named species the index has reported alongside GHK-Cu, 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.
Median total impurities
1.46%
n=41
Median largest single
0.62%
n=41
Worst single observed
1.74%
n=41
Named species observed
4 / 4
n=4
| Named species | ΔRT (min) | Δ mass (Da) | Seen in | Median % area | Max % area |
|---|---|---|---|---|---|
| apo-GHK (copper-free, −62 Da) | -0.48 | -61.930 | 100% | 0.19 | 0.94 |
| GHK-Cu 2:1 complex | +0.62 | +277.145 | 100% | 0.37 | 1.12 |
| Gly-His dipeptide (−128 Da) | -0.70 | -128.095 | 95% | 0.20 | 1.74 |
| oxidised His (+16 Da) | -0.24 | +15.995 | 95% | 0.32 | 1.46 |
apo-GHK (copper-free, −62 Da)
- Retention offset from the main peak
- -0.48 min on RG-2
- Mass difference
- -61.930 Da
- Reported in
- 41 of 41 records (100 %)
- Level when reported
- median 0.19 %, max 0.94 %
- Resolution requirement
- Baseline-resolved on the reference method.
GHK-Cu 2:1 complex
- Retention offset from the main peak
- +0.62 min on RG-2
- Mass difference
- +277.145 Da
- Reported in
- 41 of 41 records (100 %)
- Level when reported
- median 0.37 %, max 1.12 %
- Resolution requirement
- Baseline-resolved on the reference method.
Gly-His dipeptide (−128 Da)
- Retention offset from the main peak
- -0.70 min on RG-2
- Mass difference
- -128.095 Da
- Reported in
- 39 of 41 records (95 %)
- Level when reported
- median 0.20 %, max 1.74 %
- Resolution requirement
- Baseline-resolved on the reference method.
oxidised His (+16 Da)
- Retention offset from the main peak
- -0.24 min on RG-2
- Mass difference
- +15.995 Da
- Reported in
- 39 of 41 records (95 %)
- Level when reported
- median 0.32 %, max 1.46 %
- Resolution requirement
- Close-eluting — resolution below 1.2 is common and the peaks merge on short gradients.
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.
- copper dissociation at acidic pH — the mobile phase itself strips it
- His oxidation catalysed by the bound copper