Polyoxyl Oleate
(pol'' ee ox' il oh' lee ate).

Polyethylene glycol monooleate [9004-96-0].
» Polyoxyl Oleate is a mixture of the monoesters and diesters of oleic acid and mixed polyethylene glycols. It may be obtained by ethoxylation of oleic acid or by esterification of polyethylene glycols with oleic acid of animal or vegetable origin. It may contain free polyethylene glycol. The average polymer length is equivalent to either 5–6 or 10 oxyethylene units (nominal values). A suitable antioxidant may be added.
Packaging and storage— Preserve in tight containers, and store in a cool, dry place. Protect from moisture.
Labeling— Label it to indicate the number of ethylene oxide units per molecule (nominal value), and the name and concentration of any added antioxidant.
USP Reference standards 11
USP Polyoxyl Oleate RS Click to View Structure
Identification, Infrared Absorption 197F, on undried specimen.
Acid value 401: not more than 1.0, determined on 10.0 g.
Hydroxyl value 401 See table below.
Iodine value 401 See table below.
Peroxide value 401: not more than 12.0.
Saponification value 401 See table below.
  5–6 Ethylene
Oxide Units
10 Ethylene
Oxide Units
Hydroxyl value 50–70 65–90
Iodine value 50–60 27–34
Saponification value 105–120 68–85
Fatty acid composition 401 Polyoxyl Oleate exhibits the following composition profile of fatty acids, as determined in the USP general chapter section Fatty Acid Composition:
Carbon-Chain Length No. of Double Bonds Percentage (%)
14 0 5.0
16 0 16.0
18 0 6.0
16 1 8.0
18 1 65.0–88.0
18 2 18.0
18 3 4.0
>18 4.0
Alkalinity— Dissolve 2.0 g of Polyoxyl Oleate in 20 mL of alcohol. To 2 mL of this solution, add 0.05 mL of phenol red TS: the solution is not red.
Total ash 561: not more than 0.3%, determined on 1.0 g.
Water, Method I 921: not more than 2.0%.
Limit of free ethylene oxide and dioxane— Proceed as directed for Limit of free ethylene oxide and dioxane under Polyoxyl Stearyl Ether: not more than 1 µg per g of free ethylene oxide is found; and not more than 10 µg per g of dioxane is found.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Robert H. Lafaver, M.S.
Scientific Liaison
(EXC2010) Monographs - Excipients
Reference Standards RS Technical Services
USP35–NF30 Page 1918
Pharmacopeial Forum: Volume No. 29(4) Page 1121