Home / Products / Polysorbate 20 (for injection)
CAS 9005-64-5 Non-Ionic Surfactant / Emulsifier Non-Ionic Surfactant / Emulsifier

Polysorbate 20 (for injection)

IUPAC: Polyoxyethylene (20) sorbitan monolaurate View on PubChem
CAS NUMBER
9005-64-5
MOL. FORMULA
C58H114O26
MOL. WEIGHT
~1,226 g/mol
Get Commercial Quote Request Sample Request COA
Scientific Overview

Its shorter lauric-acid tail (versus Polysorbate 80's oleic-acid tail) gives Polysorbate 20 a higher HLB (16.7) and slightly different micellization behavior, making it the preferred stabilizer for certain monoclonal antibody formulations where it more effectively shields the protein from air-water interfacial stress during agitation and freeze-thaw cycling.

Polysorbate 20 is a non-ionic surfactant formed by ethoxylation of sorbitan esterified with lauric acid, used as a mild solubilizer, emulsifier, and protein-stabilizing excipient in injectable biologic and vaccine formulations.

Full Technical Data
Chemical Name Polysorbate 20 (Tween 20; Polyoxyethylene (20) Sorbitan Monolaurate)
CAS Number 9005-64-5
IUPAC Name Polyoxyethylene (20) sorbitan monolaurate
Molecular Formula C58H114O26
Molecular Weight ~1,226 g/mol g/mol
Density 1.1 g/mL (approx.)
Flash Point 110°C
Reaction Scheme
Sorbitol + Lauric Acid
Ethylene Oxide
NA
Polysorbate 20
NA
Commercial Applications

Monoclonal Antibody Stabilization

Protects therapeutic proteins from interfacial-stress-induced aggregation during manufacturing, shipping, and administration.

Vaccine Formulation

Used as an emulsifier and antigen-dispersion aid in select injectable vaccine formulations.

Diagnostic & Immunoassay Reagent

Mild non-denaturing detergent used in ELISA wash buffers and protein extraction protocols.

Ophthalmic & Topical Formulations

Functions as a solubilizer in eye drops and topical pharmaceutical products.

Market Therapeutic Focus
NON-IONIC SURFACTANT / EMULSIFIER PHARMACEUTICAL MANUFACTURING BIOLOGICS & VACCINE FORMULATION DIAGNOSTICS & IMMUNOASSAYS SPECIALTY EXCIPIENTS CRO/CDMO
Scientific Literature

Polysorbates 20 and 80 used in the formulation of protein biotherapeutics: structure and degradation pathways

Authors: Kerwin, B.A.

J. Pharm. Sci.

DOI: 10.1002/jps.21190

Effect of Polysorbate 20 and Polysorbate 80 on the Stability of Antibodies

Authors: Doshi, N. et al.

Pharm. Res.

DOI: 10.1007/s11095-014-1596-9

Degradation of Polysorbates 20 and 80: Studies on Thermal Autoxidation and Hydrolysis

Authors: Kishore, R.S.K. et al.

J. Pharm. Sci.

DOI: 10.1002/jps.22190
Peer Queries & FAQs
How does Polysorbate 20 differ from Polysorbate 80?
Polysorbate 20 has a lauric-acid (C12) fatty tail vs. Polysorbate 80's oleic-acid (C18:1) tail, giving it a higher HLB value and somewhat different protein-protection characteristics in biologic formulations.
Why do biologics need a polysorbate stabilizer?
Therapeutic proteins are prone to aggregation at air-liquid and container-liquid interfaces during shaking, pumping, and freeze-thaw; polysorbates preferentially occupy these interfaces, protecting the protein.
Is Polysorbate 20 prone to degradation?
Yes, it undergoes both hydrolytic and oxidative degradation over time, which can generate free fatty acids and peroxides that affect formulation stability.
What is the recommended storage condition?
Store in a tightly sealed, light-protected container at 2-8°C for extended shelf life; monitor peroxide value periodically.

Need a Custom Derivative or Labeled Analog?

Our R&D centers specialize in the design and process development of complex heterocyclic and chiral molecules — mg to kg scale.

Request Custom Synthesis Quote Check Manufacturing Scale