Supplier checklist:
12 things to check before you order from anyone
Every item is a document, a number or a method that either exists or does not. Run it from a product page and a certificate, on this supplier or any other, without taking anyone's word.
Why a checklist
Reputation is not a measurement
Most advice on choosing a research peptide supplier comes down to reputation: who a forum likes, who has been around, who answers email. None of that is checkable and all of it can be bought. What can be checked is paperwork, because a certificate either names a laboratory or it does not, a report number either checks out with the lab or it does not, and a product page either states a sequence or it does not.
The list below is built from those. Each item says what to look for, why it matters, and how this site answers it, with the page where the answer lives. Tick what you find. A supplier that clears the certificate group and the measurements group has done the expensive part; the rest is policy, and policy is cheap to publish and easy to read.
The list is also an audit of this site. Where an answer here is "not yet", it says so, because a checklist that grades its author generously is worth nothing.
The checklist
Fourteen checks, four groups
Ticks are saved in this browser so you can come back to a half-finished comparison. Nothing is sent anywhere.
01The certificate
A certificate with no laboratory name is a claim, not a result. The report number is what lets you ask the laboratory whether the document is theirs.
SBz ILS Laboratories, San Diego, on every certificate with its certificate number and access code. The laboratory
A supplier can edit a PDF. A laboratory portal cannot be edited by the supplier, which is the only reason it settles anything.
SBz Every ILS certificate carries a certificate number, an access code and a QR code for the laboratory portal. How to check a report
02The measurements
A purity percentage describes how much of the main peak was the main peak. It does not say the peak is the compound named on the label. Identity is a separate result, by retention time against a reference standard or by mass.
SBz Identity by chromatographic retention time against a reference standard, stated on the certificate. HPLC vs mass spectrometry
Area percent depends on the method. A figure with no method cannot be compared with any other figure.
SBz Reversed-phase HPLC, ultraviolet at 214 nm, reported as area percent. Testing standard
Powder is peptide plus counterion, water and salts. A vial can be 99 percent pure and 78 percent peptide by mass. If nobody mentions it, the label milligrams are the powder, not the peptide.
SBz Reported where the laboratory measured it, and the calculator takes it as an input. Net peptide content
These are the facts that let you check a certificate against a molecule. A page that will not commit to a sequence cannot be checked against anything.
SBz Sequence, formula, mass and CAS on each specification page, with fields still awaiting confirmation left blank rather than guessed. Specifications
03Handling and shipping
Lyophilized powder ships at ambient temperature and is stable for weeks that way. A supplier advertising cold chain for a dry powder is either shipping solution, or advertising something that does not happen.
SBz Lyophilized at minus 20 C in storage; ships as dry powder, tracked, in plain packaging. What transit does to a lot
A contaminated diluent contaminates every vial it enters. It should be tested and carry a certificate like everything else.
SBz Bacteriostatic water is tested and documented like everything else. Bacteriostatic water guide
04The business
A supplier with no way to be reached has no way to be held to anything.
SBz support@sbzindustries.com and +1 (442) 446-9583, on every page. Contact
The terms you can read before the order are the only terms that exist.
SBz Shipping and refund policies published, including what happens to a parcel that does not arrive. Refund policy
A supplier that describes outcomes is telling you it is selling something other than a research material, and it will describe its certificates with the same care.
SBz No page on this site describes what a compound does. Structure, origin and target only, and a research attestation at order. About SBz Industries
Every supplier says its material passes. The question is whether failed material is held, and whether you would ever know it existed.
SBz Material that fails is held, does not enter stock, and gets no certificate on this site. What happens to material that fails
Red flags
Six things that end the conversation
Any one of these on a product page or a certificate is enough to move on.
The same certificate on every product
One PDF reused across different compounds, or a certificate with no date and no report number. It tells you nothing about what you are buying.
A purity figure with no method
"99.7 percent" with no instrument, no wavelength and no laboratory is a number somebody typed.
No laboratory name
A certificate that names only the supplier was written by the supplier.
Cold chain for a dry powder
Lyophilized material does not need it and does not get it. The claim is marketing, and it makes the rest harder to believe.
"Pharmaceutical grade" and outcome language
Neither is a measurement. Both are a sign the supplier is describing something other than a research material.
No sequence on the product page
A supplier that will not commit to a sequence has nothing you can check a certificate against.
Questions
Common questions
How do I know if a peptide supplier is legitimate?
Run the checks on this page against a product page and a certificate. A legitimate supplier names the laboratory, publishes the certificate with the laboratory report number, dates it, and lets you check it with the laboratory directly. None of those can be faked cheaply, and a supplier that has all four has done the work.
What should a certificate of analysis for a research peptide show?
The laboratory name and report number, the compound and lot number, the identity method and result, the purity method with its wavelength and the area percent, and the date. Net peptide content where measured. The guide on reading a certificate walks through each field.
Is a supplier that only shows HPLC purity a problem?
Purity alone does not confirm identity. The question is whether identity is confirmed separately, by retention time against a reference standard or by mass, and whether the certificate says which. A supplier that reports purity with a stated method and identity with a stated method has covered both.
Does third-party testing mean the supplier is reliable?
It means a laboratory outside the supplier measured the sample the supplier sent. That is worth a great deal more than in-house testing, and it is still only as good as the link between the sample tested and the vial you receive, which is why a dated certificate with the laboratory report number matters.
Can I run this checklist on SBz Industries?
Yes, and the right-hand column of each item is where to look. Every answer given there is a page on this site that either shows the document or does not.
Run it here
Start with a certificate, not a claim
Open any certificate in the archive and run the certificate group against it. Every field the checklist asks for is on the document or it is not.
Elsewhere