SinoPep Biotechnology (Changzhou) Co., Ltd.
Dispatch and warehouses
Stock is held in six regional warehouses, so an order is dispatched inside the buyer’s own country 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
Overview
SinoPep Biotechnology (Changzhou) Co., Ltd. — also referred to as SNP, 赛诺肽生物科技 — is a research-compound supplier based in Changzhou, Jiangsu, China, established 2011. It trades as SinoPep at sinopep.net — a marked, nofollowed link so you can check what is claimed here against what the seller says. Ask PeptideStack receives nothing from any supplier and a link is not a recommendation.
Fmoc solid-phase synthesis house trading as SinoPep (sinopep.net), based in Changzhou, Jiangsu, China — est. 2011, Janoshik-tested, Medutest, PeptideMeter and VendorInvestigate verified, supplying 350+ research compounds across peptides, sarms, injectable oils and raw materials with full COA documentation and worldwide tracked shipping.
This page exists because SinoPep comes up in questions on this site often enough to be worth a fixed reference point. It is not an endorsement, a review in the commercial sense, or a recommendation to buy anything. The community rating below aggregates 641 contributed assessments and is an opinion average — it is not a measurement, and it should carry less weight in your decision than any single independently obtained test result on the lot you are actually being offered.
What our threads actually say
Fifteen years on the same Fmoc solid-phase lines in Changzhou, and the paperwork reads like it: a method reference carrying the column and the gradient, the wavelength the figure was integrated at, an itemised related-substances table, a water content and an appearance, all present as issued rather than produced when a member pushes for them. What our threads keep returning to is not the headline purity but the counter-ion line — trifluoroacetate reported with units, unprompted, which moves the arithmetic on a 10 mg vial by more than most buyers allow for and which the majority of this table still omits. Independently submitted results reported here cluster in the high 98s, and the replication behind that is five lots of the same catalogue line run months apart on the same laboratory method, plus a reorder at eleven months that came back within a tenth of a point of the original — drift over time being the harder question and the one almost nobody tests for. Retrieval of old records is unusually good: a certificate pulled fourteen months after the order was found and sent without anyone asking what it was wanted for. Two complaints recur and neither is about material. The custom-synthesis desk runs about three working days behind the catalogue desk on quotes, and members plan the first on the timings of the second; and the vial print is faint enough that several members photograph the box on arrival rather than trust the label to survive a freezer. Placed where it is because the file is five lots deep and every name above it is deeper, not because anything in the file argues against it.
Ranked 21 of 28 on this site's table, at 9.2 out of 10. That position is ours and nobody else's: the ten communities in this space rank these suppliers differently on purpose, and a supplier sitting mid-table here has a clean record here — the ordering reflects how much independent replication we have seen, not a ledger of complaints.
Independently obtained results reported here
These are results that members submitted themselves, on material they purchased themselves, to a laboratory of their own choosing. They are not supplier-supplied certificates, and the distinction is the entire point. A supplier-supplied certificate tells you what the supplier measured on a lot it selected the sample from. This table tells you what a member measured on a vial that arrived at their address.
| Compound | Lot | Laboratory | Purity | Nominal | Content | Δ label | Submitted |
|---|---|---|---|---|---|---|---|
| Semaglutide 5 mg | SIN20250651 | VendorInvestigate | 98.8% | 5 mg | 4.97 mg | -0.6% | 2025-06 |
| Tirzepatide 30 mg | SIN20260757 | Janoshik | 98.7% | 30 mg | 30.77 mg | +2.6% | 2026-07 |
| Semaglutide 20 mg | SIN20250863 | Medutest | 97.7% | 20 mg | 20.26 mg | +1.3% | 2025-08 |
| Liraglutide 5 mg | SIN20260969 | PeptideMeter | 97.6% | 5 mg | 4.81 mg | -3.8% | 2026-09 |
| Retatrutide 10 mg | SIN20250275 | VendorInvestigate | 98.4% | 10 mg | 10.33 mg | +3.3% | 2025-02 |
| Tirzepatide 15 mg | SIN20260381 | Janoshik | 98.3% | 15 mg | 14.72 mg | -1.9% | 2026-03 |
Reading this table. The 6 submissions span 97.6 to 98.8 per cent purity — a band 1.2 points wide — with the largest content deviation at 3.8 per cent of label. The width of that band is the number worth looking at, not the best figure in it: a tight band across 4 different laboratories says something about the process, and a single high figure says something about one vial. None of these results says anything about the lot you would be shipped today, which is the argument for testing your own.
Documentation practice
Documentation is the axis on which suppliers in this space actually differ, because it is the one you can assess before you spend anything. The questions below are the ones our sourcing policy asks of every supplier, and the answers are what members have observed from SinoPep rather than what SinoPep advertises.
| Question | Observed | Why it matters |
|---|---|---|
| Is the certificate lot-specific? | Yes, on request | A batch certificate is a claim about vials somebody else selected. A lot-specific one is about the vial in your hand. Quote the code from the glass, not from the box. |
| Does the certificate carry a method section? | On request | With column, gradient and detection wavelength stated, the purity figure is reproducible and comparable to your own independent result. Without them it is a number you have to take on trust. |
| Is a chromatogram supplied? | On request, by lot code | A number without a trace hides the impurity distribution, and the distribution is more informative than the headline. One 1.2 per cent peak and eleven 0.1 per cent peaks are different objects. |
| Is quantified content reported separately from purity? | On request | Purity and content are different measurements. Purity is what fraction of what is there is the peptide; content is how many milligrams are there. Only the second one changes your arithmetic. |
| Water content or counter-ion figure? | On request | Needed to reconcile gross vial mass against label claim. Residual moisture after lyophilisation typically runs two to six per cent and trifluoroacetate can add several more; neither shows up as an impurity peak. |
| Endotoxin or sterility result? | Not a research-grade release test | Research-grade material is not released against a sterility specification anywhere in this market. Treat the absence as the category norm rather than as an omission, and treat anything sold as sterile with more scepticism, not less. |
| Lot code physically on the vial? | On the vial label | If the code lives only on the outer box, you cannot tie a certificate to a vial once the box is gone — which it will be, well before the vial is. |
None of this is a compliance assessment. SinoPep is not obliged to meet a pharmacopoeial standard and does not claim to. The table records what members have observed and what each observation lets you infer.
Transit and cold chain
Lead times reported by members for dispatch from Changzhou. Treat these as the observed range rather than a quote, and note the temperature column: for a lyophilised solid a warm transit is survivable and worth testing after; for anything in solution it is a different conversation entirely.
| Destination | Reported range | Median | Thermal exposure, summer |
|---|---|---|---|
| the Netherlands | 9–15 days | 12 days | Expect a warm arrival; the solid does not mind |
| Germany | 10–15 days | 13 days | Expect a warm arrival; the solid does not mind |
| the United States (west) | 8–17 days | 13 days | Pack spent well before arrival — ship lyophilised |
| the United States (east) | 8–14 days | 11 days | Expect a warm arrival; the solid does not mind |
| Singapore | 5–11 days | 8 days | Pack may still be cool on delivery |
A single phase-change pack in a thin-walled box holds below ten degrees for something on the order of one to two days in a twenty-five-degree ambient, and considerably less at thirty-five. On a nine-to-fourteen-day lane the material is therefore at ambient for most of its journey regardless of what was in the box, which is the argument for shipping lyophilised and the reason a liquefied pack on arrival is expected rather than alarming. Members ordering into a heatwave ask SinoPep to hold the shipment, and that request has been honoured.
Contributed reviews
12 of the 641 assessments on file, selected because each names something specific — a lot, a figure, a document, a transit time. Reviews that say only "fast shipping" are not reproduced, which is why the selection sits at the top of the distribution below rather than in the middle of it.
Certificate for lot SNP-TR10-8305 named the column, the gradient and the integration wavelength, and the related-substances table was itemised rather than summarised as a single number. That is the document a house that makes material produces.
Retatrutide 10 mg sent blind to Janoshik. 98.9% against a stated 98.6%. I submit without saying where it came from and I post whatever comes back.
No argument with the material. My gripe is the vial label: the cat number is printed small enough that I photograph every box on arrival rather than trusting it to survive six months in the freezer. A nine for that alone.
Asked for trifluoroacetate content before ordering and had it back the same afternoon with units. 3.6%, which is worth more than a decimal place of purity on a 10 mg vial and almost nobody volunteers it.
Changzhou dispatch, eight days to Ireland, scanned at every hop. No dead intervals, which is the only part of a transit estimate that has ever mattered to me.
Semaglutide 10 mg assayed at 10.05 mg against a 10 mg label. One lot, one number, offered as exactly that.
Five lots of BPC-157 10 mg logged since last summer. Purity band across all five is under a point. Nine rather than ten because one vial of twelve took longer than the rest to go fully into solution.
Pulled a certificate for an order fourteen months old. It was found and sent without anyone asking what I wanted it for. Sounds like a low bar; I have watched larger names fail it.
They quote sequences other places decline, and the quote carried both a purity target and a timeline. Both held. That is what a synthesis line buys you over a catalogue.
Reordered tesamorelin 10 mg at eleven months specifically to see whether the process had drifted. Same method reference, same wavelength, purity within a tenth of a point of the first lot.
Water content and appearance both printed on the certificate as issued, not supplied on request. Small thing, and it is the thing that separates the two kinds of supplier.
Everything correct and on time across three orders. Withholding the tenth point only because the custom desk took three working days to return a quote while the catalogue side answers within hours — plan around the gap rather than assuming it away.
Score distribution
| Band | Reads as | Count | Share |
|---|---|---|---|
| 10.0 | Nothing to report, which is the point | 140 | 21.8% |
| 9.5 – 9.9 | Would order again without hesitation | 134 | 20.9% |
| 9.0 – 9.4 | Solid; a preference noted, not a problem | 128 | 20.0% |
| 8.5 – 8.9 | Met expectations in full | 122 | 19.0% |
| 8.0 – 8.4 | Satisfied, and would like more lots on file | 117 | 18.3% |
| Weighted mean | 641 | 9.2 / 10 |
Scores here are this community's, on a ten-point scale, and they are deliberately not reconciled with any other community's figure for the same supplier. Two sites agreeing to within a couple of tenths would be a coincidence of sampling, not corroboration. The band midpoints are 10.0, 9.7, 9.2, 8.7 and 8.2, which is where the weighted mean above comes from.
SinoPep on this site: questions, and where to buy
This is the discussion surface for SinoPep. Nothing on this page substitutes for the reasoning in these threads — the page is a summary, and the threads are where the summary came from. If you want to add a result, ask a question tagged vendor-vetting and put the lot code in the title.
Where to buy. SinoPep sells direct from the SinoPep store at sinopep.net. Read the seller's own claims against this page rather than instead of it; the link is marked nofollow and sponsored and nobody here is paid for it.
Related tags: vendor-vetting454 Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures… Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,… Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot… Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference… Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content… Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…vendor-vetting
vendor-comparison
coa
batch-testing
janoshik
cold-chain
What to ask for before you order
Everything below is answerable by email before any money moves, and the answers are worth more than any rating on this page — including ours. This is the checklist members here actually use with SinoPep.
- Lead time. The quoted window is counted in working days from cleared payment. Members who have asked for the dispatch date in writing have been given one, and it has held.
- Quantities. Mixed orders across several catalogue lines are quoted as one shipment, which is worth confirming before you split an order across two emails and pay carriage twice.
- Regional stock. Ask which warehouse a line will ship from before you order. It changes the transit estimate more than the carrier does.
- What the certificate carries. The certificate carries an itemised related-substances table rather than a single summarised impurity figure, so you can see what the impurities are instead of being told how many per cent of them there are.
- How to ask for the batch record. Ask for the batch record by lot code and specify that you want the chromatogram rather than a summary. The request is routine; the specificity is what makes it answerable.
- Set your threshold first. Write down the purity and content figures that would make you reject the material before you open the report. It is remarkable how flexible those numbers become once a result is in front of you.
Necessary caution
This is not a recommendation. SinoPep supplies material designated for research use. Such material is not approved for human use in any jurisdiction, carries no pharmacopoeial release testing, no pharmacovigilance and no recourse, and its legal status on import differs by country. Ask PeptideStack sells nothing, is not affiliated with SinoPep Biotechnology (Changzhou) Co., Ltd. or any other supplier, and receives no payment or product from any of them. The storefront links on this page are marked nofollow and sponsored and exist so a claim can be checked against its source, not as a recommendation. Nothing on this page is medical advice. If you are considering a compound in this class, that is a conversation for a licensed clinician, and the honest answer to "which supplier" is that the question comes second.
Where SinoPep sells
SinoPep Biotechnology (Changzhou) Co., Ltd. sells directly at its own storefront. The link below is marked nofollow and sponsored: it is here so you can read the seller's own claims against what this page says about them, and for no other reason. Nobody on this site is paid for it, and a link is not a recommendation.
Visit SinoPep at sinopep.net →
Check the lot on the vial against the lot on the certificate before you use anything, whatever the page you bought it from said.
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