If a grey-market GH product reports:
“94% purity” (usually RP-HPLC peak area)
“0.8% dimers + related proteins” (usually SEC)
…it STILL tells you almost nothing meaningful about real Somatropin quality.
And the reason is very simple:
✅ Those two numbers do NOT add up to 100%.
Where is the other 5.2%?
If they report 94% monomer + 0.8% dimers/HMW, that leaves:
5.2% unreported, unclassified impurities.
That 5.2% can be ANYTHING:
oxidised GH
deamidated GH
clipped/misprocessed GH
host-cell proteins
host-cell DNA
misfolded monomer
non-GH protein
truncated fragments
incorrect disulphide bonds
endotoxin contamination
analytical artifacts
None of this shows up in their “purity” number unless they run the full compendial battery of tests.
🔍 Why this matters
Pharma-grade Somatropin has to pass ALL of the following tests:
1. SEC chromatogram (dimers + HMW)
Limit ≤4%
Grey vial reports 0.8% — fine, but that only covers ONE impurity class.
2. RP-HPLC related proteins
Limit ≤6%
Grey vial does NOT report this separately.
3. Charged variants (CE-SDS / IEF)
Total ≤10%, single impurity ≤2%.
Grey vial never reports this.
4. Host-cell protein testing
Pharma standard: low ppm.
Grey GH: not reported.
5. DNA residual testing
Pharma: <10 pg/dose.
Grey GH: never reported.
6. Endotoxins
Pharma: strict EU/USP limits.
Grey GH: very rarely tested, often high.
7. Correct folding & isoform profile
Must match the 22 kDa isoform distribution.
Grey GH: not tested.
8. Biological potency (IU activity)
Grey GH: not measured.
⚠️ What your 94% + 0.8% actually means
It means:
> “We ran one HPLC test and one SEC test. Here are the peaks we could identify. Everything else? We don’t know.”
This is why that “94% purity” number is misleading as hell.
A pharma-grade Somatropin batch with 94% monomer has to show exactly what the other 6% is across multiple orthogonal methods.
A grey-market Somatropin batch with 94% “purity” has no requirement to tell you what the other 6% is.
One is perfectly legal and safe.
The other could be a bioactive protein, a misfolded protein, an endotoxin cocktail, or literal E. coli debris.
Everything is currently normal. Please discuss the corresponding issues in the corresponding topics. If there are scammers, please seek help from the administrator
MZ Biolabs, Finnrick (offer a free test but you'll find very mixed reviews on their service...), think there's a website called Peptidetest, Chromate
There's plenty out there, just need to find reviews on the one you want to use that fits your budget I guess