Hana O.★★★★★
The counter-ion figure was on the certificate without me asking for it. I had been asking eleven suppliers that question for two years and getting four answers.
Sourcing reference
SinoPep Biotechnology (Changzhou) Co., Ltd.
- Base
- Changzhou
- Established
- 2011
- Shop
- sinopep.net →
4.6
★★★★⯨A rating here summarises what members have said about ordering. It is not a safety rating and it cannot be one.
SinoPep Biotechnology (Changzhou) Co., Ltd., trading as SinoPep, based in Changzhou and giving 2011 as its founding year. Members have ordered from here and reported back; what follows is theirs, not the company’s.
What members have reported
Service, timings, stock and paperwork, from people who ordered.
SinoPep is the supplier members describe first by its paperwork rather than by its prices. The certificate that arrives in the box carries the peak table, the gradient, the water content and — the part this community keeps returning to — the counter-ion content, given as trifluoroacetate with a figure and units, without anyone having to ask. On a ten-milligram vial that figure does real work: purity by area percent describes what eluted, not what is in the glass, and the counter-ion is the difference between the two.
On the practicalities: no minimum order that members here have run into, a single vial treated as an ordinary first purchase, dispatch quoted at two to four working days on catalogue lines, and the compounds this community reorders held in regional stock rather than shipped from Changzhou each time. Members who asked which of their lines were held forward got the faster lane; members who did not, did not, and the two are several days apart.
The complaint members raise is not about material. Written quotations for sequences outside the catalogue have taken about three working days, where a catalogue question is answered the same afternoon. More than one person here has planned a bespoke order on catalogue timings and been caught out by the gap.
The testing record, and its limits
Analysis from four independent services — Janoshik, Medutest, PeptideMeter and VendorInvestigate — exists against this catalogue, and members here have commissioned some of it themselves rather than reading only the published set. Where the two have been compared on this page the independent figures have sat within a few tenths of the published ones, and on every comparison posted here the published figure was the more conservative of the two.
One comparison on this page is worth more than the rest: a member repurchased a catalogue line eleven months after an earlier order and had both determined on the same stated method. The two results were a tenth of a point apart. Drift over time is the question that a single impressive figure cannot answer, and it is the one almost nobody is in a position to test.
The limit belongs to the method rather than to the supplier. A purity certificate reports purity. It does not report sterility, endotoxin load, residual solvents or heavy metals, and no number on this page should be read as if it did.
Checked against unverifiable
The left column is what somebody could confirm. The right column is what nobody can.
Dispatch and warehouses
Stock is held regionally, so an order is sent from within your 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
Can be checked
- That the shop trades at sinopep.net, gives Changzhou as its base and 2011 as its founding year
- That analysis from four independent services exists against this catalogue, and that members here commissioned some of it themselves
- That the certificate carries a peak table, the gradient, the water content and a quantified counter-ion figure, because members have posted redacted copies
- That members here have reordered the same line more than a year apart and had both lots determined on the same stated method
Cannot be checked
- Which lines are synthesised on this company’s own resin and which arrive through a contract arrangement — that is not visible from outside any supplier
- What happened to your specific vial between manufacture and dispatch: where it sat, at what temperature, and for how long
- Sterility, endotoxin load, residual solvents and heavy metals, none of which a purity certificate reports
- Whether the counter-ion figure on one certificate is representative of the line, or of that lot alone
Questions to ask before you order
Take these verbatim. The answers, and the non-answers, are informative.
- Please send the lot-specific certificate for the code printed on my vial, including the peak table.
- What is the counter-ion content for this lot, and is it reported as trifluoroacetate or as acetate?
- Is peptide content by weight reported for this lot, and by which method?
- Which regional stock will this ship from, and what is the current dispatch window from there?
Member reports
Published in full, in the words they were written in.
Laila T.★★★★★
Asked which gradient the purity figure came off and got the column, the buffer and the run time back in one reply.
Ferran V.★★★★★
Sent a vial to Janoshik without telling them where it came from. 98.9% against a stated 98.6%. The published number was the careful one.
Sofia Ma.★★★★★
Eight days from Changzhou to Dublin and it was scanned the whole way. I have had faster deliveries that went dark for four days and I preferred this one.
Diego B.★★★★★
Five lots of the same line over ten months and the purity band is under a point wide. That tells me more than any single figure could.
Ruben B.★★★★★
I asked for a certificate for something I bought fourteen months ago. It arrived the next day and nobody asked me why.
Bastian So.★★★★★
Weighed eleven vials against the label. All within two per cent. Nobody talks about fill consistency and it is harder to get right than purity.
Diego A.★★★★★
Reordered the same line eleven months on specifically to see whether anything had changed. Same method, same wavelength, a tenth of a point apart.
Halima S.★★★★★
They quoted a sequence that two other places would not even reply about, with a purity target and a timeline, and both held.
Enzo★★★★★
Content came back at 10.05 mg against a 10 mg label. One lot, and I am reporting it as one lot.
Jarno F.★★★★☆
No complaint about the material. The custom desk took three working days to send a price when the catalogue side answers within hours. Plan for it.
Line C.★★★★☆
The print on the vial is small. I photograph the box when it arrives now, which I did not used to do.
Gustav L.★★★★★
Asked which resin a line was built on and got a straight answer rather than being passed to sales.
Marit N.★★★★★
Related substances came as an itemised table rather than one number. One impurity and twelve impurities are not the same situation and a total hides which you have.
Nayeli F.★★★★★
Third order in a row where the paperwork matched the vial matched the invoice. Nothing to report, which is the report.
Sena E.★★★★★
Water content and appearance were both on the certificate as issued. Small things, and they are the things that tell you what kind of operation you are dealing with.
Leila I.★★★★☆
Eleven days to Spain, at the slow end of the window they quoted, but it never stopped moving.
Rina A.★★★★★
Not affiliated with them. Two orders, one independent test, both fine. Posting because this page was thin when I was deciding.
Where SinoPep sells
So you can read their account against this one.
SinoPep Biotechnology (Changzhou) Co., Ltd. sells from its own shop. The link below is marked nofollow and sponsored. We are paid nothing for it, it is not a recommendation, and nothing on that site removes the risk described at the top of this page.