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
1.44%
n=72
Median largest single
0.65%
n=72
Worst single observed
1.66%
n=72
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% | 0.17 | 0.92 |
| GHK-Cu 2:1 complex | +0.62 | +277.145 | 100% | 0.45 | 1.22 |
| oxidised His (+16 Da) | -0.24 | +15.995 | 100% | 0.24 | 1.66 |
| Gly-His dipeptide (−128 Da) | -0.70 | -128.095 | 99% | 0.17 | 1.62 |
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
- 72 of 72 records (100 %)
- Level when reported
- median 0.17 %, max 0.92 %
- How it separates
- 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
- 72 of 72 records (100 %)
- Level when reported
- median 0.45 %, max 1.22 %
- How it separates
- 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
- 72 of 72 records (100 %)
- Level when reported
- median 0.24 %, max 1.66 %
- 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.
Gly-His dipeptide (−128 Da)
- Retention offset from the main peak
- -0.70 min on RG-2
- Mass difference
- -128.095 Da
- Reported in
- 71 of 72 records (99 %)
- Level when reported
- median 0.17 %, max 1.62 %
- How it separates
- 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.
- copper dissociation at acidic pH — the mobile phase itself strips it
- His oxidation catalysed by the bound copper