l.rahimi97/100
Chromatogram reproduced on the certificate with the integration limits visible; reported area checked against the trace and agrees to the first decimal.
PPG — PolyPeptide Group (Hangzhou) Co., Ltd.
Hangzhou, CN · established 2006. The index holds 213 assay reports across 38 batches and 25 compounds, contributed by 6 laboratories. Every figure below is computed from those records and from nothing else.
Where PPG sells
PolyPeptide Group (Hangzhou) Co., Ltd. sells from its own storefront. The link is marked nofollow and sponsored: it exists so the figures on this scorecard can be read against what the supplier itself publishes. The index is paid nothing for it and a link is not an assessment.
Visit PPG at polypeptidegroup.net →
Every figure above describes lots the index has seen. It says nothing about the lot you are offered, and the only check that does is the one on the certificate against the vial.
Block 1
Identification
Business facts, held constant across the index and not derived from the data. The index sells nothing and takes no supplier payment for placement; the storefront link below is marked nofollow and sponsored so a record can be checked against the seller, and is not a recommendation.
- Legal name
- PolyPeptide Group (Hangzhou) Co., Ltd.
- Short code in this index
- PPG
- Also known as
- PPG · PolyPeptide · PolyPeptide Group (Hangzhou) · 多肽集团
- Domain
- polypeptidegroup.net →
- City
- Hangzhou
- Region
- Zhejiang
- Country
- CN
- Established
- 2006
- First record in index
- 27 Apr 2024
- Most recent record
- 03 Aug 2026
Block 1b
Dispatch and regional stock
Counted from the chain-of-custody line on this supplier's own records, which names the route each vial travelled to the laboratory, and from the on-record reviews below. The index has no sight of any supplier's warehouse network and publishes none.
Domestic-warehouse route
13.6%
n=213
Retail, shipped to the buyer
74.6%
n=213
Direct to the laboratory
4.2%
n=213
Median courier leg, direct despatch
6d
n=9
| Route to the laboratory | Records | Share |
|---|---|---|
| Domestic warehouse despatch | 29 | 13.6% |
| Retail purchase, shipped to the buyer | 121 | 56.8% |
| Retail purchase via a third-party forwarder | 38 | 17.8% |
| Supplier despatch direct to the laboratory | 9 | 4.2% |
| Laboratory retained-sample archive | 16 | 7.5% |
Every record here carries a chain-of-custody line and that line names the route the vial travelled. Of the 213 PPG records the index holds, 29 reached the contributing laboratory from a domestic warehouse rather than as a cross-border consignment, covering 12 of the 25 compounds PPG is represented by here — BPC-157, Retatrutide, GHRP-2, L-Glutathione (reduced), GHRP-6, Melanotan II and 6 further compounds. Those are the PPG lines this index has actually seen arrive from regional stock, and they are a count of consignments rather than a stock listing: a line missing from them may simply never have been submitted for assay.
No contributor to this index has named a regional stock location for PPG. 29 of its records nevertheless arrived by a domestic-warehouse route, so stock is held somewhere; the index does not know where and will not guess.
The index measures nothing about lead time — it assays material, it does not buy it. What it has is PPG's own reviewers: 3 of the 26 on-record reviews state a quoted window and what happened against it. Where PPG despatched a sample direct to a laboratory, the courier leg ran a median 6 days across 9 such consignments — that is a transit time the index can see, and it is not the same thing as a lead time. The reviews are reproduced in full in Block 11.
Block 2
Headline statistics
Each figure carries the n it was computed from. The n= badge next to a statistic is the number of records it was computed from. Below n=8 the badge is amber. Below n=3 the statistic is suppressed and the individual values are shown instead.
Median purity
99.45%
n=213
Interquartile range
0.72pp
n=213
10th percentile
98.55%
n=213
Pass rate vs index spec
100.0%
n=213
Median recovery vs claim
97.3%
n=128
Median water
4.60%
n=213
Median |mass error|
2.7ppm
n=168
Records carrying a flag
13.1%
n=213
Block 3
Reproducibility across independent tests of one lot
Where the same physical lot was assayed more than once, the spread between those results is a property of the material and the fill, not of the market. It is the rarest and most informative statistic on this page, and it exists only for lots someone tested twice.
Median within-batch spread
0.51pp
n=27
Index median spread
0.67pp
n=28
Lots tested 3+ times
27
n=38
Across the 27 PPG lots in the index with three or more independent assays, the median spread between the highest and lowest purity result on one lot is 0.51 pp. Interpreting that number requires the laboratory repeatability figures: the best contributing laboratory here repeats to 0.16 pp and the worst to 0.34 pp, so a within-lot spread under about 0.5 pp is indistinguishable from measurement noise and a spread above 1 pp is a statement about the material.
Block 4
Supplier certificate against independent measurement
The supplier's own COA purity figure for a lot, minus the median of the index's independent observations of the same physical lot. Positive means the certificate reads higher than the measurement. Rule AX-R05 fires above 1.5 pp.
Median COA divergence
+0.02pp
n=38
Index median divergence
+0.06pp
n=28
Divergences in the supplier's favour
50%
n=38
Divergences beyond 1 pp
0%
n=38
Block 5
Provenance — where the tested material came from
Supplier-supplied samples are weaker evidence than independently purchased ones, because the supplier chose the vial. The index measures the size of that effect rather than assuming it.
Buyer-sourced median
99.45%
n=188
Supplier-supplied median
99.44%
n=9
Supplier-supplied share of records
4.2%
n=213
Block 6
Documentation completeness
The score is not an opinion about paperwork. Each component is the share of PPG batches in the index whose certificate carries that field, weighted as set out on the scoring rubric.
Documentation score
93/100
n=38
Index median score
85/100
n=28
| Certificate field | Batches carrying it | Rubric weight | |
|---|---|---|---|
| Purity figure stated | 100% | 25 points | |
| Analytical method stated (column, gradient, wavelength) | 79% | 25 points | |
| Peptide content stated | 71% | 20 points | |
| Endotoxin stated | 32% | 15 points | |
| Named impurities rather than a total | 74% | 15 points |
Block 7
Coverage by compound
The delta column is this supplier's median minus the index-wide median for the same compound, which is the only comparison worth making: comparing a supplier's aggregate against another supplier's aggregate compares their product mixes as much as their process control.
| Compound | Class | Reports | Median % | Index median % | Δ (pp) | Index spec | Pass % |
|---|---|---|---|---|---|---|---|
| Retatrutide | Incretin | 35 | 98.56 | 98.37 | +0.19 | 96.5 | 100 |
| BPC-157 | Tissue-repair | 27 | 99.82 | 99.16 | +0.66 | 98.0 | 100 |
| CJC-1295 (no DAC) | Growth-hormone | 18 | 99.66 | 99.09 | +0.57 | 98.0 | 100 |
| Tirzepatide | Incretin | 18 | 99.10 | 98.55 | +0.55 | 97.0 | 100 |
| L-Glutathione (reduced) | Short | 13 | 99.45 | 99.33 | +0.12 | 98.5 | 100 |
| GHRP-6 | Growth-hormone | 11 | 99.65 | 99.54 | +0.11 | 99.0 | 100 |
| Ipamorelin | Growth-hormone | 11 | 99.78 | 99.47 | +0.31 | 99.0 | 100 |
| SS-31 (Elamipretide) | Metabolic | 11 | 99.76 | 99.53 | +0.23 | 98.5 | 100 |
| AOD-9604 | Metabolic | 10 | 99.41 | 99.29 | +0.12 | 98.0 | 100 |
| MGF | Growth-hormone | 9 | 99.29 | 99.29 | 0.00 | 97.5 | 100 |
| Semaglutide | Incretin | 9 | 98.64 | 98.89 | -0.25 | 97.0 | 100 |
| Melanotan II | Melanocortin-receptor | 8 | 99.92 | 99.42 | +0.50 | 98.5 | 100 |
| TB-500 | Tissue-repair | 7 n=7 | 99.39 | 99.53 | -0.14 | 98.5 | 100 |
| MK-677 (Ibutamoren mesylate) | Non-peptide | 4 n=4 | 99.62 | 99.49 | +0.13 | 98.5 | 100 |
| GHRP-2 | Growth-hormone | 4 n=4 | 99.68 | 99.28 | +0.40 | 99.0 | 100 |
| Tesamorelin | Growth-hormone | 3 n=3 | 98.74 | 98.29 | +0.45 | 97.0 | 100 |
| 5-Amino-1MQ | Non-peptide | 3 n=3 | 99.38 | 99.45 | -0.08 | 98.0 | 100 |
| Thymosin α1 | Tissue-repair | 3 n=3 | 98.98 | 99.40 | -0.42 | 97.5 | 100 |
| CJC-1295 with DAC | Growth-hormone | 2 n=2 | n<3 | 98.95 | — | 97.5 | 100 |
| Sermorelin | Growth-hormone | 2 n=2 | n<3 | 99.06 | — | 98.0 | 100 |
| Cagrilintide | Incretin | 1 n=1 | n<3 | 98.69 | — | 96.5 | 100 |
| Semax | Neuroactive | 1 n=1 | n<3 | 99.46 | — | 98.5 | 100 |
| Enclomiphene citrate | Non-peptide | 1 n=1 | n<3 | 99.44 | — | 98.5 | 100 |
| PT-141 (Bremelanotide) | Melanocortin-receptor | 1 n=1 | n<3 | 99.38 | — | 98.5 | 100 |
| NAD+ | Non-peptide | 1 n=1 | n<3 | 99.28 | — | 97.0 | 100 |
Full per-compound breakdown with distributions and caveats →
Block 8
Quarterly trend
Submission volume is not market share and a quarterly median is not a trend unless the compound mix held still. Both caveats apply to every row below.
Median purity by quarter
Quarters with fewer than two purity records are gaps in the line rather than zeroes.
Coverage growth
Records added per quarter. Growth here is index coverage, not supplier volume.
| Quarter | Batches | Reports | Median purity | Range | Flagged |
|---|---|---|---|---|---|
| 2024-Q1 | 0 | 0 | n<3 | — | 0 |
| 2024-Q2 | 2 | 19 | 99.40 | 98.39–99.93 | 2 |
| 2024-Q3 | 2 | 10 | 99.42 | 99.08–99.87 | 1 |
| 2024-Q4 | 2 | 15 | 99.86 | 99.52–99.93 | 2 |
| 2025-Q1 | 4 | 26 | 99.68 | 98.50–99.93 | 3 |
| 2025-Q2 | 6 | 34 | 99.31 | 98.46–99.93 | 8 |
| 2025-Q3 | 3 | 7 | 99.49 | 99.34–99.92 | 1 |
| 2025-Q4 | 5 | 17 | 99.38 | 98.10–99.93 | 2 |
| 2026-Q1 | 6 | 30 | 99.65 | 99.10–99.93 | 4 |
| 2026-Q2 | 7 | 52 | 99.31 | 97.70–99.93 | 3 |
| 2026-Q3 | 1 | 3 | 98.74 | 98.54–98.91 | 2 |
Block 9
Which laboratory produced these numbers
Laboratories disagree with each other by a measured amount. A supplier tested mostly by one laboratory carries that laboratory's offset in its aggregate, and the adjusted column removes it.
| Laboratory | Reports | Median purity | Lab bias (pp) | Bias-adjusted |
|---|---|---|---|---|
| Janoshik | 100 | 99.42 | +0.00 | 99.42 |
| PeptideMeter | 46 | 99.40 | -0.05 | 99.45 |
| Medutest | 23 | 99.55 | +0.08 | 99.47 |
| VendorInvestigate | 13 | 99.50 | -0.11 | 99.61 |
| Nordanalyt | 16 | 99.47 | +0.02 | 99.45 |
| Kestrel | 15 | 99.93 | +0.24 | 99.69 |
Bias figures are estimated from paired same-lot comparisons and are published with their confidence intervals on inter-lab agreement.
Block 10
What this data does and does not show
Block 11
On-the-record reviews 26
Reviews are signed statements from index contributors about their own testing of this supplier's material. They are opinions attached to evidence, and they are not used in any statistic on this page.
95.0/ 100811 ratings across the index network
a.balogun98/100
Gradient table, column identifier and detection wavelength printed beside the trace. Determination is reproducible from the document alone.
v.yildiz99/100
Independent determination on lot PPG-2603-0261 returned 98.2% against a declared 98.3%. Within method repeatability.
t.vanhecke97/100
Query on a possible shoulder at the principal peak answered with the expanded region of the trace rather than an assurance.
f.achebe98/100
Peptide content reported separately from area percent on all certificates held. Distinct quantities; conflation is the common documentary error.
t.teixeira99/100
Two lots of one line compared at an eleven month interval. Declared figures a tenth of a point apart; traces overlay within baseline noise.
p.petrov97/100
First order placed at single-vial quantity. Documentation complete, transit as quoted, independent determination 97.8%.
am.ekstrom98/100
Water by Karl Fischer with the determination method named. Bears on delivered mass for lyophilised presentations.
ay.roos99/100
Catalogue exceeds 350 lines; records held here cover four. Breadth of catalogue is not breadth of evidence.
s.bhattacharya97/100
Supplementary certificate for a lot released nineteen months earlier produced from records with the trace intact.
em.mbeki98/100
Related substances itemised by individual impurity with retention times assigned rather than reported as one total.
h.ogunleye99/100
Lot identifier agreed across vial, certificate and commercial documentation on every consignment examined.
a.espinoza97/100
Reconstitution produced a clear solution without extended agitation. Appearance observation, not a determination.
is.beaulieu98/100
ESI-MS identity reported against a stated expected mass alongside the chromatographic determination.
h.vermeulen99/100
Custom synthesis quoted with the schedule on the face of the quotation and completed two days inside it.
f.sorensen97/100
Four-day dispatch delay notified before the quoted window elapsed, with a revised date that held.
d.guerrero98/100
Counter-ion identity and content answered with a figure and a unit within one working day. Trifluoroacetate at 3.9%.
t.zielinski99/100
Four units from one consignment weighed against declared fill; all within two per cent gross.
l.rautio97/100
One lot submitted to two independent services. Both agreed with one another and with the declared figure to a tenth of a point.
s.haddad98/100
Repeat determination on the same line at eleven months returned 98.0% against 98.1% originally. No drift in this sample.
ma.agyeman99/100
Single lot identifier across every unit in the consignment, permitting an intra-consignment comparison.
lu.krastev97/100
Cold chain held to arrival on day seven with the pack solid. Shipment temperature record enclosed.
co.vasquez98/100
Declared figure not revised upward between the certificate and the commercial documentation.
l.pereira99/100
Nine consignments across fourteen months without substitution, reformulation or a line becoming unavailable after payment.
no.laurent97/100
Stability statement written against a named storage condition rather than a bare shelf life, so the claim is evaluable.
f.lokken98/100
Residual-solvent screen present on a line whose synthesis route calls for one, without a request having been made.
Block 12
Most recent records
Block 13
Contributor annotations on PPG records 394
Annotations are this index's only discussion surface: signed technical comments attached to a specific record by a named contributor. They are not moderated for agreement with the index's own arithmetic. The most recent on PPG material are below, each linked to the record it sits on.
On small molecules an assay against a named reference standard is both identity and content in one determination. Its absence leaves both open.
Filtration at 0.22 µm removes organisms and not endotoxin. Endotoxin removal needs ultrafiltration or affinity adsorption and neither is routine at this scale.
The reported figure derives from the plate count and the retention gap, via the pharmacopoeial form with the sum of both peak widths in the denominator. It is a calculated quantity, not a measured one, and it inherits the plate count's uncertainty.
Where the nearest species is a diastereomer of Tesamorelin, resolution is the only thing that separates them at all — no mass measurement will. The compound fingerprint states what is achievable and on what method.
An orthogonal identity method on the same lot would make this the strongest class of record the index holds. Mass plus retention is already better than most.
Two instruments or it is not confirmed, and this record is one instrument. It is a good one instrument, and the index records it as confirmed rather than corroborated for that reason.
Lot PPG-2604-X7060 on the vial matches the certificate that came with it. That is the check every buyer can do in ten seconds and most do not.
Custody from checkout to injection is documented on this record. Provenance plus custody is what makes a single result generalise past the vial it came from.
Every annotation the index holds on PPG material sits on its own record; the full set is reachable from the record listing and from each contributor's page. To read them against what PPG itself publishes, open polypeptidegroup.net → alongside.
Block 14
Where to buy PPG
PolyPeptide Group (Hangzhou) Co., Ltd. sells direct from polypeptidegroup.net. Everything on this page describes lots the index has already seen; the certificate that matters is the one that arrives with the vial you order, and the lot code on it should match the vial. Ask for the lot-specific document rather than the batch-level summary, and ask for the integration report if you intend to reconcile the figure yourself.
Go to the PPG store at polypeptidegroup.net →
Marked nofollow and sponsored. The index is paid nothing for it, takes no commission, and a link is not an assessment. Research compounds. Not medical advice. Nothing on this site is a safety assessment and nothing on it is approved for human use.