Carbomer 941
»Carbomer 941is a high molecular weight polymer of acrylic acid cross-linked with allyl ethers of pentaerythritol.Carbomer 941,previously dried in vacuum at 80for 1hour,contains not less than 56.0percent and not more than 68.0percent of carboxylic acid (–COOH)groups.The viscosity of a neutralized 0.5percent aqueous dispersion of Carbomer 941is between 4000and 11,000centipoises.
Packaging and storage— Preserve in tight containers.
Labeling— Label it to indicate that it is not intended for internal use.
Viscosity— Proceed as directed in the test for Viscosityunder Carbomer 934P,except to use a spindle having a disk 2.11cm in diameter and 0.16cm high attached to a shaft 0.32cm in diameter,the distance from the top of the disk to the lower tip of the shaft being 2.7cm,and the immersion depth being 4.92cm (No.5spindle).The viscosity is between 4000and 11,000centipoises.
Limit of benzene— Proceed as directed in the test for Limit of benzeneunder Carbomer 934P,except to use about 20mg of Carbomer 941,accurately weighed,instead of about 1g of Carbomer 934P,to prepare the Test solution.Calculate the percentage of benzene in the portion of Carbomer 941taken by the formula:
10(C/W)(rU/rS),
in which Cis the concentration,in µg per mL,of benzene in the Standard solution;Wis the weight,in mg,of Carbomer 941taken to prepare the Test solution;and rUand rSare the benzene peak responses obtained from the Test solutionand the Standard solution,respectively:not more than 0.5%is found.
Other requirements— It meets the requirements for Identification,Loss on drying,Heavy metals,andAssay for carboxylic acid content underCarbomer 934P.
Auxiliary Information— Staff Liaison:Catherine Sheehan,B.Sc.,Scientist
Expert Committee:(EMC)Excipients:Monograph Content
USP28–NF23Page 2974
Pharmacopeial Forum:Volume No.27(6)Page 3338
Phone Number:1-301-816-8262