Technical library
How to judge the best peptide supplier for your market, in eight questions.
There is no single best peptide supplier in this category, and any supplier telling you otherwise is describing itself. There is a supplier that can answer eight questions about your market, and one that cannot. This is the checklist, with our own answer to each.
The tests
Eight questions, in the order worth asking them
Ask for a certificate before you order
Redacted is fine. What comes back tells you more than any purity figure on a homepage. If it arrives only after payment, that is the answer.
Check it carries a batch number
Without one it describes a product in general, not the thing you were sent. Everything else on the document is then unverifiable.
Look for a result, not a specification
A range is an intention. A single figure for a named batch is a measurement.
Find out who ran the analysis
In-house or independent, it should say. An unattributed result is a claim with nobody standing behind it.
Ask what the minimum order quantity is measured in
Per compound or per order changes the number completely. So does international units against milligrams.
Ask who the legal entity is
A registration number and a jurisdiction. Without a named contracting party there is nobody to enforce the terms against.
Ask what happens when a batch fails
The answer reveals whether there is a quality process or a sales process.
Ask them about your own market
A supplier who can say nothing about the rules where you sell will be no help when a shipment is stopped.
Why these eight
Each resolves to a documented fact
Purity, certification and delivery claims are common across this category, which limits how far they distinguish one supplier from another.
The questions below each resolve to a documented fact rather than a claim: a named entity, a dated certificate, a stated basis for a minimum order quantity.
Our answers. The contracting entity and registration number are on the About page. A redacted certificate is available before a first order. The structure of the supply chain is set out in full.
Origin
Why "is it a Chinese peptide supplier" is usually the wrong question
Most research peptide in the world is synthesised in a small number of facilities, and a large share of those are in China. That is true of sellers who say so and of sellers who do not, which is why origin alone separates almost nobody from anybody.
Four questions do change your position, and none of them is answered by a flag on a website:
- Who holds the stock when you order. Material already in Europe and material ordered from a factory on receipt of your payment are different lead times and different risks.
- Who tested this batch, and when. A certificate from the synthesiser, a certificate from the seller and an independent certificate are three different documents.
- Which entity is on the invoice. A registration number in a jurisdiction where you could actually bring a claim, or not.
- Who carries the liability if the shipment is stopped. Read the terms before you need them, because this is settled at order time and not at the border.
A supplier that will not tell you where stock is held has told you something. Ask us the same question and hold the answer against the eight tests above.
Jurisdiction
The best supplier depends on where you sell
Since 1 January 2021 a shipment from the EU into Great Britain is an import rather than an intra-market movement. Buying into the UK is a licensing question before it is a price question: a wholesale dealer's licence, a Responsible Person for Import, an EORI number, and a separate per-consignment Home Office licence for the substances the UK schedules as controlled drugs. A supplier who cannot discuss that is not a supplier for the UK.
Inside the EU, movement between member states is not an import, but national classification still differs market by market, and the question of whether a given compound can be supplied at all is answered nationally rather than at EU level.
Questions
About vetting
Is a higher purity figure a better supplier?
Not on its own. Two laboratories can produce different figures for the same material by different methods and both be honest. A figure with a named method and a batch behind it beats a larger figure with neither.
Should we insist on third-party analysis?
It is stronger evidence, because the party has no commercial interest in the result. An honest in-house certificate that names its issuer still beats an unattributed third-party claim.
How many suppliers should we run this on?
Applying it to an existing supply arrangement is as useful as applying it to a new one.
What is the single fastest test?
Ask for a redacted certificate before you order. Response time and content together tell you most of what you need, and it costs you one email.
How do I check a peptide supplier is legitimate?
Four things are checkable in an afternoon. A named legal entity with a registration number you can find in a national register. A VAT number that validates. A batch-specific certificate supplied before payment rather than after. And a straight answer about the rules in the market where you sell. Reviews and forum threads tell you about someone's service, which is worth knowing, but they tell you nothing about the material.
Does it matter if a peptide supplier is based in China?
Less than most buyers expect, because most of the world's research peptide is synthesised in a small number of facilities and a large share of those are in China regardless of who sells it. What matters is who holds the stock when you order, who tested the batch, which entity is on the invoice and who carries the liability if a shipment is stopped.
What changes when we buy into the UK rather than into the EU?
Since 1 January 2021 it is an import. That means a wholesale dealer's licence, a Responsible Person for Import, an EORI number, and a separate per-consignment Home Office licence for the compounds the UK schedules as controlled drugs. The UK market page sets out the regime with its sources.
Put us through it
Ask for a redacted certificate, our entity details, or the position in your market.
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