Most sourcing pages for this ingredient stop at the name. This one starts after it: you already know you want Diaminopyrimidine Oxide, and the open question is what changes in the specification, the paperwork, and the supplier conversation depending on whether you are filling a leave-on scalp serum, a tonic, or a single-dose ampoule. Those three formats put different demands on the same raw material, and the differences are worth settling before a sample request rather than after a pilot batch.
The name you buy under
The INCI name is Diaminopyrimidine Oxide. Aminexil is a trade name belonging to the L'Oréal group, and Kopexil is another name in common use for the same substance. On a purchase order and in an ingredient declaration, the INCI name is the one that travels; a trade name identifies whose branded material a formula originally used, which is not the same claim. We supply the INCI ingredient, not any brand owner's finished material. If the naming question is what brought you here, our naming guide for Aminexil, Diaminopyrimidine Oxide and Kopexil covers it properly.
It is not a peptide, and that changes the questions
Diaminopyrimidine Oxide is a small heterocyclic molecule — a pyrimidine N-oxide carrying two amino groups, molecular formula C4H6N4O, molecular weight 126.12. It sits in scalp-care briefs next to peptides, and it is often sourced in the same basket, but it is not one.
The practical consequence is that the questions you would ask a peptide supplier do not all transfer. Sequence confirmation and peptide-content assay are not the relevant checks here; identity confirmation, assay against a reference standard, related substances, water content, and residual solvents are. A supplier who answers questions about this material in peptide vocabulary is worth a second look.
What changes between serum, tonic, and ampoule
The material is the same in all three. What differs is which of its properties your process actually stresses.
Leave-on scalp serum. The dominant variables are solubility in your chosen solvent system and behaviour over the shelf life of a multi-use pack that gets opened daily. Ask for solubility data in the solvent system you actually intend to use, not a generic figure, and plan stability on the real pack.
Tonic. Higher water or alcohol content and larger fill volumes shift attention to solution clarity and colour over time, and to how the material behaves in your specific water quality. Batch-to-batch consistency in appearance matters more here because the product is transparent and any drift is visible to the customer.
Single-dose ampoule. Small fills concentrate every tolerance you have. Content uniformity across the filling run, and the accuracy of the assay figure you dosed against, matter more than in a 100 mL bottle. This is also the format where a supplier's ability to hold a tight specification across repeat batches gets tested first.
If your range spans more than one of these, decide early whether all formats will reference a single specification or whether the ampoule gets a tighter one. Both are defensible; leaving it undecided is not.
The documents that should travel with a batch
For a serious evaluation, request the specification sheet, a batch-specific COA, and SDS/MSDS, and read them together rather than filing them. Two habits are worth building in:
- Check that the COA is for the batch you were sent, not a generic sheet reused across shipments. A single certificate covering many shipments tells you less than it appears to.
- Check that the assay method and the reference standard are stated. A percentage without a method behind it is a number, not a result.
Our general approach to reading these documents is set out in the COA, HPLC and LC-MS documentation review guide, and what belongs in a specification sheet before it feeds packaging copy is covered here.
What stays your job
Formulation compatibility is decided by your own bench work and finished-product stability testing, informed by the supplier's technical data — not by a compatibility claim on a datasheet. Use levels are set by your formulation assessment against that data, and the regulatory status and permitted claims for this ingredient in each destination market must be reviewed by you or your regulatory adviser before any wording is fixed. Positioning stays cosmetic and appearance-focused throughout; that boundary is a claims decision, not a sourcing one, and it belongs in your target-market review.
If you are choosing between this material and a peptide for the same scalp-care brief, the comparison with Acetyl Tetrapeptide-3 sets out where each tends to land.
What we can support
We supply Diaminopyrimidine Oxide for scalp-care formulation projects and can provide COA and SDS/MSDS documentation, a specification sheet with purity information, samples for formulation evaluation, and bulk quotation against a stated quantity and destination market. OEM/ODM discussion is available where a project calls for it. The current specification scope is on the Aminexil (Diaminopyrimidine Oxide) material page.
Frequently Asked Questions
What is the INCI name of Aminexil?
Diaminopyrimidine Oxide. Aminexil is a L'Oréal trade name for the same substance, and Kopexil is another name in common use. CAS 74638-76-9.
Is Diaminopyrimidine Oxide a peptide?
No. It is a small heterocyclic molecule, C4H6N4O, molecular weight 126.12. It is frequently sourced alongside cosmetic peptides for scalp-care projects, which is why the two are often discussed together.
Does the specification change between a serum and an ampoule?
The material does not, but which parameters you hold tightly can. Small single-dose fills put more weight on content uniformity and on the accuracy of the assay figure you dose against, so some projects hold a tighter specification for ampoules than for larger multi-use packs.
Can you provide batch documentation?
Yes. COA and SDS/MSDS documentation and a specification sheet can be provided through our B2B inquiry process, and samples are available for formulation evaluation.