The vendor directory is one section of Amino Axiom, a free research information and tracking platform that also includes a compound library, price tables, a comparison tool, and a glossary. The directory gives each research-materials vendor its own profile page. A profile collects the facts a buyer would otherwise assemble by hand from a storefront: which payment rails the vendor accepts, how many compounds it lists, and how it is rated.
For a researcher in the growth-factor and receptor-binding space, the directory answers a narrow question: before comparing individual listings, which suppliers are worth looking at, and what does each one look like on paper? This FAQ describes what a profile shows and how that information can be read. It says nothing about any use of the materials.
What does a vendor profile contain?
Three kinds of information appear on a profile. The first is payment rails, the list of payment methods the vendor accepts. The second is the compound count, the number of distinct compounds the vendor currently lists. The third is the rating, a summary score attached to the vendor in the directory. Each of these is a descriptive field, not a recommendation, and each is worth reading for what it does and does not say.
Payment rails are a practical filter. A purchasing office at an institution may be limited to certain methods, and a profile that shows the accepted rails lets a researcher rule vendors in or out before reading any product page. The compound count is a rough indicator of breadth. A vendor listing a handful of compounds is a different kind of supplier from one listing several hundred, and neither number says anything about the quality of any single item.
How should the compound count be read for growth-factor work?
The count is a headline number, and growth-factor research uses a narrow slice of any catalog. A vendor with a large count may list few or no large recombinant proteins, because those are produced and documented very differently from short synthetic peptides.
A researcher looking for Follistatin is looking for a secreted glycoprotein studied as a ligand trap for activin and GDF-8 within the TGF-β superfamily. The Amino Kinetics catalog describes it at roughly 37,000 to 40,000 Da in the recombinant form and roughly 3,780 Da in the synthetic truncated form, under CAS number 117628-82-7. A vendor whose count is high because it lists many short peptides may not carry this material at all.
The practical reading, then, is to treat the count as a reason to open the profile and then check the individual compound listings. The directory narrows the field. The product pages settle whether a given vendor lists the specific form a binding experiment requires.
What do the ratings tell a researcher?
A rating is a summary figure, and like any summary it hides the distribution behind it. It reflects how the vendor is scored in the directory. It does not describe the identity, purity, or documentation of any particular lot, and it cannot, because those are properties of a batch rather than of a seller.
Researchers who work in receptor-binding assays tend to care about lot-level variables: purity, counter-ion content, aggregation state for larger proteins, and whether analytical documentation accompanies the material. None of those can be read from a star score. The rating is best used the way a reading list is used: it suggests where to look first, and the actual evaluation comes from the vendor's specification and documentation. A highly rated vendor with thin documentation for a given compound is still a thin-documentation listing for that compound.
How would a researcher use the directory with a modified analog such as IGF-1 LR3?
IGF-1 LR3 is a modified analog of insulin-like growth factor 1, studied for its reduced affinity for IGF binding proteins and its engagement of the IGF-1 receptor. The Amino Kinetics catalog lists it under CAS number 946870-92-4 with a molecular weight of 9117.5 g/mol and the formula C400H625N111O115S9. A compound of this size and complexity is not stocked by every supplier, so the directory is useful mainly as a way to build a shortlist.
A workable sequence is to filter the directory down to vendors whose payment rails fit the purchasing situation, open each remaining profile, and note which ones plausibly carry larger analogs given their compound count and the kind of catalog they run. From there the researcher moves to the individual product pages. At that stage the identifying values become the anchors: a listing that states a molecular weight far from 9117.5 g/mol for the analog deserves a closer look at what is actually being sold. The directory does not perform this check, but it gets the researcher to the right set of pages quickly.
What about modified compounds such as PEG-MGF?
PEG-MGF shows why a profile is only a starting point. The Amino Kinetics catalog lists a core peptide molecular weight of 2867.2 g/mol with the formula C121H200N42O39 and CAS number 108174-48-7, and notes that the effective mass varies with the PEG chain.
Two vendors can describe a PEGylated compound quite differently, and nothing on a vendor profile captures that difference. The profile tells a researcher that a vendor lists a compound with this name. Whether the PEG component is described the same way across vendors is a question for the product pages and the accompanying documentation.
This is a recurring limit of any directory. It operates at the level of the vendor, while the scientific questions in a binding or reporter-gene study operate at the level of the specific material. The two levels complement each other, and confusing them is the usual source of mistakes.
How does the directory relate to the rest of Amino Axiom?
The directory is one of several views on the same underlying set of vendors and compounds. The price tables show what each vendor currently lists for a given compound. The vendor status tracker, a separate page, records which vendors are no longer operating. The comparison tool places two compounds side by side.
A sensible order for a researcher is to use the directory to learn who the vendors are, the status information to confirm they are active, and the price and library pages to look at specific compounds.
Keeping the roles separate helps. The directory describes sellers, the library describes compounds, and neither substitutes for reading the primary documentation that accompanies a specific lot.
Where do the Amino Kinetics listings fit?
Amino Kinetics is one supplier a researcher may encounter, providing growth-factor and receptor-binding materials in lyophilized form with analytical documentation available for each batch. Specifications for the compounds above are on their product pages, and the complete research catalog is at all compounds. For background on the protein itself, see the follistatin and activin signaling overview, and for reading lot documentation, the analytical standards and sourcing guide. As with any vendor, the listings here should be checked against the library entry and the batch documentation before conclusions are drawn.
This article is provided for research and informational purposes only. The compounds discussed are research chemicals intended for laboratory use only. They are not drugs, supplements, or food, and are not intended to diagnose, treat, cure, or prevent any disease. Amino Kinetics does not sell products intended for human or animal use. Amino Axiom is an independent information platform, and its content does not constitute guidance on the use of any material. Researchers are responsible for compliance with all applicable local, state, and federal regulations governing the purchase and use of research materials.
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Common questions
A vendor profile collects three descriptive fields: the payment rails the vendor accepts, the number of distinct compounds it lists, and a summary rating attached in the directory. Each is a descriptive field rather than a recommendation, and none says anything about the identity or purity of a particular lot.
No. A rating is a summary score for the vendor and does not describe the identity, purity, or documentation of any specific lot, because those are properties of a batch rather than a seller. Lot-level evaluation comes from the vendor's specification and the analytical documentation that accompanies the material.
Treat the count as a reason to open the profile, not as a measure of fit. Growth-factor work uses a narrow slice of any catalog, and a high count may come from many short peptides while listing few large recombinant proteins such as Follistatin (roughly 37,000 to 40,000 Da).
No. The directory operates at the vendor level and does not check individual listings. A researcher compares a listing's stated values against the library entry, for example 9117.5 g/mol for IGF-1 LR3 or a 2867.2 g/mol core peptide for PEG-MGF, on the product page itself.
The directory describes vendors, while the separate vendor status tracker records which vendors are no longer operating. A sensible order is to use the directory to learn who the vendors are, the tracker to confirm they are active, and the price and library pages to look at specific compounds.
