Last reviewed: October 2026 · Cleared Peptides research team
Polysorbate 80 is polyoxyethylene (20) sorbitan monooleate, a nonionic surfactant mixture. Chemical catalogs assign CAS 9005-65-6. A single molecular formula is not printed here because the material is a polymer mixture, not one discrete molecule. A public compound-name lookup does not return one structure, which matches that description.
| Name | Polysorbate 80 |
|---|---|
| Other names | Polyoxyethylene sorbitan monooleate; Tween 80 in supplier catalogs |
| CAS number | 9005-65-6, the catalog number for the mixture |
| Formula | Not one formula. It is a mixture of related chains. |
| Class | Nonionic surfactant. Not a peptide. |
| Catalog status | Not a current Cleared Peptides lot. |
Laboratory note
Surfactants change how a solid wets and how a peptide adsorbs to surfaces in an assay. This page does not give a percentage or a formulation.
Frequently Asked Questions
Why is there no molecular weight?
Polysorbate 80 is a mixture. One molecular weight would be misleading.
Is Tween 80 a different chemical?
Tween 80 is a supplier name used for polysorbate 80, not a second CAS substance.
Is this for human use?
No. Laboratory reference only.
Selected References
Registry records and peer-reviewed literature listed as scientific background. Citation does not imply endorsement, a benefit, or any use.
- Catalog identity: polyoxyethylene (20) sorbitan monooleate, CAS 9005-65-6. Cited as the mixture name, not as a single-molecule structure.
Research Use Only Notice
This guide is provided for educational and laboratory reference purposes. It summarizes published structural and biochemical literature. It does not describe, recommend, or imply any use in humans or animals. These materials are not drugs, foods, cosmetics, or dietary supplements on this page, are not offered here as a treatment, and no dosing or administration instructions are provided. Cleared Peptides does not currently list a lot for every compound on this page.
