Lauroyl Polyoxylglycerides
(Title for this new monograph—to become official January 1, 2011)
(Prior to January 1, 2011, the current practice of labeling the article of commerce with the name Lauroyl Macrogolglycerides may be continued.)
» Lauroyl Polyoxylglycerides is a mixture of monoesters, diesters, and triesters of glycerol and monoesters and diesters of polyethylene glycols. The polyethylene glycols used have a mean molecular weight between 300 and 1500. It is produced by partial alcoholysis of saturated oils, mainly containing triglycerides of lauric acid with polyethylene glycols, by esterification of glycerol and polyethylene glycols with fatty acids, or as a mixture of glycerol esters and ethylene oxide condensate with the fatty acids of the hydrogenated oils. It may contain free polyethylene glycols.
Packaging and storage—
Preserve in tight containers, protected from light and moisture. Store at controlled room temperature.
Labeling—
Label it to indicate the type and the average nominal molecular weight of polyethylene glycols used as part of the official title.
USP Reference standards 
11
—
11—
USP Lauroyl Polyoxylglycerides RS
Identification—
B:
Thin-Layer Chromatographic Identification Test 201—
201—
Test solution:
50 mg per mL, in methylene chloride.
Standard solution:
50 mg of USP Lauroyl Polyoxylglycerides RS per mL, in methylene chloride.
Application volume:
10 µL.
Developing solvent system:
a mixture of ether and hexanes (7:3).
Spray reagent—
Prepare a 0.1 mg per mL solution of rhodamine B in alcohol.
Procedure—
Proceed as directed in the chapter. Then spray the plate with Spray reagent, and locate the spots on the plate by examination under UV light at a wavelength of 365 nm: the RF values of the principal spots obtained from the Test solution correspond to those obtained from the Standard solution.
C:
It meets the requirements of the test for Fatty acid composition.
Acid value 401:
not more than 2.0, determined on a 2.0-g specimen.
401:
not more than 2.0, determined on a 2.0-g specimen.
Hydroxyl value 401:
within the range specified in Table 1 for the labeled type when determined on a 1.0-g specimen, accurately weighed.
401:
within the range specified in Table 1 for the labeled type when determined on a 1.0-g specimen, accurately weighed.
Table 1
| Type of Polyethylene Glycols |
Hydroxyl Value |
|---|---|
| 300 | 65–85 |
| 400 | 60–80 |
| 600 | 50–70 |
| 1500 | 36–56 |
Iodine value 401:
not more than 2.0.
401:
not more than 2.0.
Peroxide value 401:
not more than 6.0, determined on a 2.0-g specimen.
401:
not more than 6.0, determined on a 2.0-g specimen.
Saponification value 401:
within the range specified in Table 2 for the labeled type when determined on a 2.0-g specimen.
401:
within the range specified in Table 2 for the labeled type when determined on a 2.0-g specimen.
Table 2
| Type of Polyethylene Glycols |
Saponification Value |
|---|---|
| 300 | 190–204 |
| 400 | 170–190 |
| 600 | 150–170 |
| 1500 | 79–93 |
Fatty acid composition 401:
Lauroyl Polyoxylglycerides exhibits the following composition profile of fatty acids, as determined in the section Fatty Acid Composition under Fats and Fixed Oils 401 (see Table 3).
401:
Lauroyl Polyoxylglycerides exhibits the following composition profile of fatty acids, as determined in the section Fatty Acid Composition under Fats and Fixed Oils 401 (see Table 3).
Table 3
| Carbon-Chain Length |
Number of Double Bonds |
Percentage (%) |
|---|---|---|
| 8 | 0 |  15.0 |
| 10 | 0 | 12.0 |
| 12 | 0 | 30.0–50.0 |
| 14 | 0 | 5.0–25.0 |
| 16 | 0 | 4.0–25.0 |
| 18 | 0 | 5.0–35.0 |
Water, Method I 921:
not more than 1.0%, determined on a 1.0-g specimen. Use as the solvent anhydrous pyridine or a mixture of methylene chloride and anhydrous methanol (7:3).
921:
not more than 1.0%, determined on a 1.0-g specimen. Use as the solvent anhydrous pyridine or a mixture of methylene chloride and anhydrous methanol (7:3).
Total ash 561:
not more than 0.1%.
561:
not more than 0.1%.
Heavy metals, Method II 231:
not more than 0.001%.
231:
not more than 0.001%.
Alkaline impurities—
Weigh 5.0 g of Lauroyl Polyoxylglycerides, heat slightly until the test substance melts, add 10 mL of alcohol and 0.05 mL of bromophenol blue TS, and mix well. While the solution is still warm, titrate with 0.01 N hydrochloric acid VS to change the color to yellow: not more than 1.0 mL of 0.01 N hydrochloric acid is required.
Limit of free ethylene oxide and dioxane—
Proceed as directed in the test for Limit of free ethylene oxide and dioxane under Caprylocaproyl Polyoxylglycerides: not more than 1 µg of ethylene oxide per g is found; and not more than 10 µg of dioxane per g is found.
Limit of free glycerol—
Proceed as directed in the test for Limit of free glycerol under Caprylocaproyl Polyoxylglycerides: not more than 5.0% 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 1-301-816-8335 |
(EXC2010) Monographs - Excipients |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 1840
Pharmacopeial Forum: Volume No. 34(5) Page 1224