Sofia L.★★★★★
I asked which gradient the purity figure came off and got the column, the buffer and the run time back in one reply. Nobody had answered that question for me before.
Sourcing reference
GenScript Biotech Corporation
- Base
- Nanjing
- Established
- 2002
4.6
★★★★⯨A rating here summarises what members have said about ordering. It is not a safety rating and it cannot be one.
GenScript Biotech Corporation, trading as GenScript Peptides, based in Nanjing and giving 2002 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.
GSP is the supplier members describe as a synthesis house rather than a repackager. Solid-phase work is the business, and the reports read that way: questions about a sequence or a coupling answered by somebody who runs the chemistry, a stated route for anything unusual, and a lead time rather than an assurance when the answer is that the line has to be made.
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 sent from Nanjing every time. The catalogue is wide — members put it above three hundred and fifty research compounds — and custom synthesis is quoted individually with a date on the quotation.
The certificate is what reports keep returning to. It carries the lot code, the assay method with its column and gradient, the detection wavelength, the peak table and the water content. Members who asked for the synthesis record behind a lot describe one email with the lot code in the subject line, answered inside a working day.
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, which is what agreement looks like when two laboratories run different gradients.
The limit belongs to the method rather than to the company. A chromatographic purity figure is a proportion of what is present in one sample, from one lot, on one day. It does not say how much peptide is in the vial, and it says nothing at all about sterility or endotoxin, which are separate assays with separate costs that nobody here has commissioned for any supplier.
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 genscriptpeptides.com, gives Nanjing as its base and 2002 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 and the water content, because members have posted redacted copies
- That members here have reordered across more than one year and described the documentation as unchanged between orders
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 a stated crude-to-purified yield describes the lot you were sent or a representative run
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.
- Is peptide content by weight reported for this lot, and by which method?
- Was this lot synthesised in house, and can you state the purification step used?
- 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.
Ruben K.★★★★★
Lot GSP-25-207. Same code on the vial, the certificate and the invoice. It is a low bar and I have watched other places trip over it.
Marta D.★★★★☆
Everything was correct and complete, but the first dispatch ran a day past the window I was quoted, and they did not tell me until I asked. That is the only thing I would change.
Ade O.★★★★★
One vial, treated exactly like a real order, full document set in the box. I had ordered one deliberately to see how a small customer gets handled.
Ingrid H.★★★★★
Janoshik returned 98.7% against a stated 98.9%. Somebody here explained that two tenths between laboratories is a methods difference, and I have stopped reading small gaps as bad faith.
Tomasz W.★★★☆☆
The material and the paperwork were fine. My complaint is the custom quote: I waited five days for a number on a non-catalogue sequence, and the catalogue side of the business is far quicker than that. Worth knowing before you plan around it.
Nadia S.★★★★★
Water content was already printed rather than something I had to request. A guide here told me to ask for it by name and I never needed to.
Callum B.★★★★★
Three orders across four months and the certificate has been laid out identically each time. Sameness between orders turns out to be what I actually wanted.
Yuna P.★★★★☆
Impurities broken out individually rather than rolled into one total, which I appreciated. A point off only because the vial label print was faint enough that I photographed it before it could wear.
Elias M.★★★★★
They quoted a lead time on something two other suppliers had ignored my emails about, and then met the date. I would rather have a date than an apology.
Bea C.★★★★★
Nine vials, one lot, nine identical codes. Checking the whole box took less time than making tea.
Hugo F.★★★★☆
PeptideMeter came back at 98.1% on a blind submission, which is solid. The reason this is not a five is that reconstitution left a faint haze on one vial of three. It cleared, but I noticed it.
Amira T.★★★★★
I asked for a certificate from an order thirteen months old, half expecting silence. They found it and sent it without asking why I wanted it.
Lars E.★★★★★
Second year on the same line and the figure has not drifted: 98.4% then, 98.5% now, and the same document layout on both.
Priyanka R.★★★★★
I sent a badly worded, nervous email and got a patient answer with no sales language in it anywhere. If you are at the frightened stage, ask them.
Dominik V.★★★★☆
Customs paperwork right first time and the cold pack still firm on arrival. Marked down only because the outer box was softer than I would like for glass. Nothing broke, but that was partly luck.
Freya N.★★★★★
Content by weight reported separately from purity, so I could do the arithmetic myself instead of assuming my way through it.
Oscar J.★★★★★
This is a record of my orders and not a promise about yours, and none of it is approved for anybody to take. Within those limits: nine orders, no substitutions, no surprises.
Where GSP sells
So you can read their account against this one.
GenScript Biotech Corporation 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.