Compound compare is a tool within Amino Axiom, a free research information and tracking platform. A researcher selects two compounds and the tool shows them next to each other: their structural characteristics in one column pair and the published research literature associated with each in another. The tool is at Amino Axiom's compare page, and the platform's homepage is aminoaxiom.com.
In growth-factor and receptor-binding research, many compounds are discussed in the same breath because they act on related pathways, yet they differ in size, structure, and modification. A side-by-side view is a way to keep those differences visible while reading. This FAQ explains what the comparison shows and how a researcher in this lane might read it. It describes the tool as a reference view and does not address use of any material.
What does a comparison show?
Two panels. The structural side lists the descriptive facts for each compound: its class, its size, and where available its formula and identifiers. The literature side summarizes the kinds of published findings associated with each compound, so a researcher can see at a glance whether the two have been studied in similar systems or in different ones. The tool reports what is on record. It does not rank the compounds or rate one as better than the other, and a researcher should not read it as doing so.
The value is mostly in what it prevents. Comparing two compounds from memory, or across two separate browser tabs, invites the mistake of treating similar names as similar molecules. A paired view makes the differences hard to overlook.
How would a researcher compare Follistatin and IGF-1 LR3?
These two are a good test of the tool because they have little in common structurally and a lot in common in conversation. Follistatin is 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, and gives no single molecular formula because the recombinant protein is not a fixed small molecule.
IGF-1 LR3 is a modified analog of insulin-like growth factor 1, studied for reduced affinity for IGF binding proteins and engagement of the IGF-1 receptor. The catalog lists it at 9117.5 g/mol with the formula C400H625N111O115S9 and CAS number 946870-92-4.
Side by side, the structural contrast is immediate. One is a binding protein that sequesters ligands; the other is a ligand analog that engages a receptor. One has a size that depends on the form; the other has a defined mass. A researcher designing a study around ligand sequestration and a study around receptor engagement is working with different experimental logic, and the comparison makes that distinction concrete before any materials are ordered.
What does a worked comparison of the three catalog compounds look like?
The table below lays out the catalog facts for the three compounds used in this FAQ, the same kind of fields the structural panel draws on. All values are copied from the Amino Kinetics catalog as of October 2026.
~37,000 to 40,000 Da (recombinant); ~3780 Da (synthetic truncated)
9117.5 g/mol
2867.2 g/mol (core peptide; varies with PEG chain)
Formula
N/A (recombinant protein)
C400H625N111O115S9
C121H200N42O39
CAS number
117628-82-7
946870-92-4
108174-48-7
Read across a row, the table shows how much the size and definition of these compounds differ. Read down a column, it gives the identifiers worth copying into a lab record.
How does the literature panel help?
It shows the context in which each compound has been studied. For two growth-factor compounds, the literature side lets a researcher see whether the published work for each centers on the same kinds of systems, for example cell-based binding or reporter-gene assays, or on different ones. If the overlap is small, that is itself informative: it suggests that conclusions from one compound's literature should not be carried over to the other.
The panel summarizes the existence and type of published findings. It is not a substitute for reading the papers, and it does not evaluate their quality. A researcher uses it to decide which primary sources to open next, not to draw conclusions from the summary alone.
What does the tool add for a modified compound such as PEG-MGF?
PEG-MGF is a case where the structural panel carries a caveat. 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. Comparing it against IGF-1 LR3, for instance, a researcher sees one entry with a defined mass and one whose mass depends on a modification.
The point to hold onto is that the formula and mass in a comparison describe the core molecule. For a PEGylated compound the real mass of a given lot depends on the polymer attached, so the comparison is a framing device and the lot documentation is the authority on what a specific material is. Reading the structural panel as a starting description, rather than as a lot specification, avoids a common error.
Can the comparison be used to decide which compound a study needs?
It can narrow the question, but it cannot answer it. The tool tells a researcher how two compounds differ on record. The decision about which one fits a study depends on the hypothesis, the assay, and the system, none of which the tool knows. A researcher who has a clear experimental question will find the comparison a quick way to confirm that two candidates are not interchangeable. A researcher who does not yet have the question will find that the comparison raises more of them, which is a reasonable outcome.
It is also worth being clear about what the tool does not do. It does not verify the identity or purity of any vendor's material, and it does not report on suppliers. Those questions belong to the documentation for a specific lot and to other Amino Axiom pages, the vendor directory and status tracker among them.
How should a researcher record a comparison?
By noting the pair of compounds and the date. The tool reflects the platform's current content, which can be updated, and a lab that cites a comparison in a methods note or a planning document should be able to say when it was read. The identifiers, CAS number, molecular weight, and formula, are the stable values worth copying into the record, since they anchor the compound independently of how any tool presents it.
Where do the Amino Kinetics listings fit?
Amino Kinetics supplies growth-factor and receptor-binding materials in lyophilized form with analytical documentation available for each batch. The product pages for the three compounds above carry the specifications referenced here, and the full research catalog is at all compounds. For background on how these compounds are discussed in the literature, see the follistatin and activin signaling overview, and for how to read lot documentation, the analytical standards and sourcing guide. Any listing, including these, should be checked against the compound 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.
Reference
Common questions
No. The tool places two compounds side by side, with structural facts in one panel and the associated published literature in another, and it does not rank or rate either one. It reports what is on record, so any judgment about fit for a study stays with the researcher.
The comparison lists descriptive facts such as class, size, formula, and identifiers where available. In the Amino Kinetics catalog, Follistatin is roughly 37,000 to 40,000 Da in recombinant form under CAS 117628-82-7, while IGF-1 LR3 is 9117.5 g/mol, C400H625N111O115S9, under CAS 946870-92-4.
Its listed mass describes only the core peptide. The catalog gives 2867.2 g/mol for the core, but the effective mass of a given lot varies with the attached PEG chain. The comparison is a starting description, and batch documentation is the authority on what a specific lot actually contains.
No. The compare tool describes compounds, not suppliers or lots. Identity and purity are properties of a specific batch and are assessed from its analytical documentation. The comparison helps confirm that two candidate compounds are not interchangeable, which is a separate question from what a lot contains.
Note the two compounds and the date the comparison was read, because the platform's content can be updated. The stable anchors worth copying into a methods note are the CAS number, molecular weight, and formula, since they identify each compound independently of how any tool presents them.
