Polysorbate 60

This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition

Issued and maintained by the United States Pharmacopeial Convention (USP)

DOWNLOAD PDF HERE

1 DEFINITION

Polysorbate 60 is a mixture of stearate and palmitate esters of Sorbitol and its anhydrides copolymerized with about 20 moles of ethylene oxide for each mole of sorbitol and sorbitol anhydrides. The fatty acids may be of vegetable, animal, or synthetic origin.

2 IDENTIFICATION

Change to read:

A. Spectroscopic Identification Tests 〈197〉, Infrared Spectroscopy: 197F (CN 1-May-2020)

B. It meets the requirements in the Assay for Composition of Fatty Acids

3 ASSAY

Composition of Fatty Acids

Polysorbate 60 exhibits the composition profiles of fatty acids shown in Table 1, as determined in Fats and Fixed Oils 〈401〉, Fatty Acid

Composition.

Table 1

4 IMPURITIES

Residue on Ignition 〈281〉: NMT 0.25%

Ethylene Oxide and Dioxane, Method II 〈228〉

Acceptance criteria

Ethylene oxide: NMT 1 ppm

Dioxane: NMT 10 ppm

5 SPECIFIC TESTS

Fats and Fixed Oils, Acid Value 〈401〉

Sample: 10.0 g of Polysorbate 60

Analysis: Transfer the Sample to a wide-mouth, 250-mL conical flask, and add 50 mL of neutralized alcohol. Heat on a steam bath nearly to boiling, shaking thoroughly occasionally while heating. Invert a beaker over the mouth of the flask, cool under running water, and add 5 drops of phenolphthalein TS. Titrate with 0.1 N sodium hydroxide VS. Calculate the acid value as directed in the chapter.

Acceptance criteria: NMT 2.0

Fats and Fixed Oils, Hydroxyl Value 〈401〉: 81–96

Fats and Fixed Oils, Peroxide Value 〈401〉

Sample: 10.0 g

Saturated potassium iodide solution: Prepare a saturated solution of potassium iodide in carbon dioxide-free water. Make sure the solution remains saturated as indicated by the presence of undissolved crystals.

Analysis: Introduce the Sample into a 100-mL beaker, and dissolve with 20 mL of glacial acetic acid. Add 1 mL of Saturated potassium iodide solution, mix, and allow to stand for 1 min. Add 50 mL of carbon dioxide-free water and a magnetic stirring bar. Titrate with 0.01 M sodium thiosulfate VS, determining the endpoint potentiometrically (see Titrimetry 〈541〉). Perform a blank titration.

Calculate the peroxide value as directed in the chapter.

Acceptance criteria: NMT 10.0

Fats and Fixed Oils, Saponification Value 〈401〉: 45–55

Water Determination, Method I 〈921〉: NMT 3.0%

6 ADDITIONAL REQUIREMENTS

Packaging and Storage: Preserve in tight containers, protected from light and moisture. Store at room temperature.

Labeling: Label to indicate whether the fatty acids are derived from animal, vegetable, or synthetic sources.

USP Reference Standards 〈11〉

USP Polysorbate 60 RS