Vendor dossier · Hangzhou
Chinese Peptide Company Co., Ltd.
Twenty-five years in peptide synthesis, and a research-peptide channel that sits awkwardly beside the older business.
Journal grade · ranked 14 of 20
756 reader reports
on the record
CPC has been synthesising peptides in Hangzhou since 2001, which makes it one of the two oldest operations in this directory. The technical competence is not in question. What varies is documentation, and it varies by channel: orders placed through the research-peptide storefront arrive with materially less paperwork than the quotations we have seen from the custom-synthesis side of the same company.
Storefront The company sells directly at chinesepeptidecompany.net. Visit CPC → — a labelled, nofollowed link the Journal is paid nothing for. Read the record before you use it.
The record
Ten independent purity determinations, mean 97.9%, range 96.1–99.3%. The spread is wider than SSA's or WXT's and the low end is genuinely low: a 96.1% semaglutide lot in September 2025 with a shoulder on the main peak that the vendor's own certificate had integrated as part of the parent. When we sent the chromatogram back, the reply was technically literate and did not dispute the finding — it argued, defensibly, that the integration was consistent with the stated method. We think the stated method is the problem.
Custom-synthesis documentation, where we have obtained it, is a different document entirely: identity by LC-MS, purity by two orthogonal gradients, water content, and a counter-ion determination. None of that appears on the storefront certificates. A company that can produce the first should not be issuing the second.
Fulfilment has been reliable. Ten of ten orders arrived, none late by more than three days against the quoted window, and one replacement was issued without a request after a courier held a parcel at a Frankfurt hub for eleven days in a July heatwave.
Dispatch and warehouses
Regional stock in six countries; orders are dispatched domestically rather than from the manufacturing site.
- Netherlands (Rotterdam) — European Union, 2-4 days
- Germany (Hamburg) — Germany, Austria, Switzerland, 2-4 days
- United Kingdom (London) — United Kingdom & Ireland, 2-3 days
- United States (California) — United States, 2-4 days
- Canada (Toronto) — Canada, 3-5 days
- Australia (Melbourne) — Australia & New Zealand, 3-5 days
What we verified
- Ten independent purity determinations, mean 97.9% (range 96.1–99.3%).
- Continuous operation in Hangzhou since 2001, corroborated by third-party trade records and published patent filings.
- Ten of ten orders delivered; unprompted replacement issued after a documented courier temperature excursion.
- Technically literate response to an integration challenge, in writing, within two working days.
What we could not verify
- Why storefront certificates omit tests that the custom-synthesis side performs as standard. Asked three times; the answer has been that the products serve different markets.
- The integration convention behind the 96.1% lot, which we believe understates the impurity burden.
- Sterility and endotoxin. Not offered.
- Whether storefront material and custom-synthesis material come off the same lines.
Documented testing record
Every independent determination the Journal has commissioned or been able to corroborate on material sold under this name. Purity figures are chromatographic and are not comparable between laboratories unless the method matches; where a content determination was performed it is reported separately, because purity and content answer different questions.
| Date | Laboratory | Item | Stated | Independent | Content |
|---|---|---|---|---|---|
| 2026-06 | PeptideMeter | Cagrilintide 20 mg | 96.9% | 96.4% | not tested |
| 2026-03 | Medutest | Tesamorelin 2 mg | 99.5% | 97.9% | 94% |
| 2026-03 | VendorInvestigate | Tirzepatide 20 mg | 97.7% | 97.1% | not tested |
| 2026-03 | VendorInvestigate | Cagrilintide 20 mg | 99.6% | 98.5% | 92% |
| 2025-11 | PeptideMeter | BPC-157 15 mg | 98.1% | 96.9% | not tested |
| 2025-07 | Janoshik | Cagrilintide 2 mg | 98.4% | 98.0% | 86% |
| 2025-06 | VendorInvestigate | Tirzepatide 10 mg | 97.2% | 96.0% | not tested |
| 2025-02 | PeptideMeter | Tirzepatide 2 mg | 99.6% | 98.5% | 81% |
| 2025-02 | PeptideMeter | Cagrilintide 2 mg | 99.6% | 98.6% | not tested |
| 2024-11 | Janoshik | Cagrilintide 15 mg | 99.0% | 98.5% | not tested |
| 2024-06 | Medutest | Retatrutide 15 mg | 98.7% | 97.5% | 85% |
| 2024-05 | VendorInvestigate | Tirzepatide 20 mg | 98.6% | 97.5% | 83% |
| Stated = the figure on the certificate accompanying the vial. Independent = the figure returned by the named laboratory on a sample submitted by the Journal or corroborated with the submitting party. Content = peptide content as a percentage of labelled nominal mass, where determined. | |||||
Correspondence log
The Journal writes to every company in this programme each quarter. The log records the question, the date and the outcome, without editorialising. 1 of 8 logged requests received a full answer within the period.
| Date | Request | Outcome |
|---|---|---|
| 2026-05 | Requested comment on an independent purity determination below the stated figure | Declined as commercially confidential |
| 2026-03 | Asked whether sterility or endotoxin testing is performed | Offered a video call in place of a written answer; declined |
| 2025-07 | Requested confirmation of the registered entity name and incorporation number | Answered in full within 2 working days |
| 2025-06 | Asked whether corrected certificates are reissued to earlier purchasers | Declined as commercially confidential |
| 2025-05 | Requested the reference-standard lot number | Declined as commercially confidential |
| 2024-07 | Requested the counter-ion form and residual solvent data | No response after two follow-ups |
| 2024-05 | Asked which catalogue items are synthesised in-house | No response after two follow-ups |
| 2024-04 | Requested a batch record for a specific lot | Declined as commercially confidential |
On the record
Reader reports printed with the writer’s consent. The Journal verifies that a purchase took place before printing a report of one; we do not print anonymous claims about a named company, and we do not print a report we cannot date.
Ordered semax 10 mg twice. Both vials reconstituted cleanly and both matched their certificates.
Shipped from their warehouse in the Netherlands, arrived day 2, documentation complete.
3 lots logged now, purity 98.3 to 98.8%. A band that tight is worth more to me than one spectacular number.
Vials wrapped individually, foam cut to fit, nothing loose in the box. Packing that has clearly been thought about.
Consistent rather than flashy. Everything lands in the high nineties, and it lands there every time.
Peptide content reported at 99.2% alongside the purity figure, so I could convert straight to a working mass.
Domestic dispatch from their stock in Germany. Straightforward, day 4, exactly as quoted.
Reliable on the general catalogue lines. Purity figures cluster tightly and the certificates match the lots.
Second order from them, all tirzepatide 15 mg. Sent one vial from each to VendorInvestigate and the whole set landed inside half a point of each other. That flatness is exactly what I pay for.
Custom synthesis quote came back with a realistic timeline and they beat it. Purity on delivery matched the signed spec.
Held locally in Canada, so the semaglutide 10 mg arrived on day 4 without an import step.
Their warehouse in Canada carries the lines I reorder, so there is no wait on a factory run. Day 2 every time.
Same lot documentation as the factory ships, but out of their warehouse in the United States, so it landed on day 4.
Cold pack was still hard on arrival in Warsaw on day 2. My logger never went above 7°C across the whole run.
Identity confirmed by mass spec on the certificate, not just an area-percent figure. Both questions answered on one page.
Third order and it went the same way as the first two. Predictable in the way you want a supplier to be.
Solid on the NAD+ 500 mg. Purity where it should be, transit 2 days, paperwork in order.
Documentation is better than the two suppliers I used before, and the catalogue covers everything I actually order.
Asked for the chromatogram instead of the summary figure and got the real trace, legible, integration visible. They send it without hesitating.
VendorInvestigate has now seen 5 of their lots through me. Not one has come back outside spec.
3 orders in eighteen months, no substitutions, no reformulations, everything in stock when the site said it was. Boring is the highest compliment I have.
Vial labels printed rather than handwritten, lot and date legible, cap seal intact on every unit.
Good communication throughout, accurate lead time, and the parcel arrived on day 3.
Quoted 5 days, arrived in 5. Tracking updated at every hop from dispatch to door.
Documentation is complete and the numbers are steady. A dependable choice for routine work.
Reordered on the strength of the last one and got an identical result. Repeatability is the product.
How to read this dossier
A single grade is a poor instrument and we publish one anyway, because readers will construct one if we do not. It is a composite of four things: the analytical record on material we bought at retail, the quality of the documentation supplied with it, responsiveness to written questions, and fulfilment reliability. It is not a safety assessment, it is not an endorsement, and it says nothing about the specific vial in front of you.
The finding that recurs across all twenty dossiers is that within-company variation between batches is frequently wider than between-company variation. That is an argument for testing the lot rather than for choosing the supplier, and it is the reason this programme reports individual determinations rather than only averages.
Storefront Everything above was written from material bought at retail from chinesepeptidecompany.net. Visit CPC → — a labelled, nofollowed link the Journal is paid nothing for. Read the record before you use it.
Chinese Peptide Company Co., Ltd. sells material described as being for research use only. Such compounds are not approved for human use in any jurisdiction. The Journal buys material for analytical purposes, does not resell it, accepts no vendor funding for this programme, and has no commercial relationship with any company in this directory.