Carbomer 934
(kar' boe mer).
(Any article currently titled Carbomer 934 that is manufactured without the use of benzene will be officially titled Carbomer Homopolymer after January 1, 2011, and will meet the requirements of the new Carbomer Homopolymer monograph after January 1, 2007.)
» Carbomer 934 is a high molecular weight polymer of acrylic acid cross-linked with allyl ethers of sucrose. Carbomer 934, previously dried in vacuum at 80 for 1 hour, contains not less than 56.0 percent and not more than 68.0 percent of carboxylic acid (–COOH) groups. The viscosity of a neutralized 0.5 percent aqueous dispersion of Carbomer 934 is between 30,500 and 39,400 mPa·s. [note—Effective January 1, 2011, the heading of this monograph will no longer constitute the official title for Carbomer 934 manufactured without the use of benzene. When benzene is not used in the manufacturing process, the name of the article will be Carbomer Homopolymer and will meet the requirements of the Carbomer Homopolymer monograph. ]
Packaging and storage— Preserve in tight containers. No storage requirements specified.
Labeling— Label it to indicate that it is not intended for internal use. A carbomer homopolymer manufactured using benzene and complying with the unique requirements of this monograph will be officially titled Carbomer 934 and will not be referred to as Carbomer Homopolymer.
Viscosity— Proceed as directed in the test for Viscosity under Carbomer 934P. It is between 30,500 and 39,400 mPa·s.
Limit of benzene— Proceed as directed in the test for Limit of benzene under Carbomer 934P, except to use about 20 mg of Carbomer 934, accurately weighed, instead of about 1 g of Carbomer 934P, to prepare the Test solution. Calculate the percentage of benzene in the portion of Carbomer 934 taken by the formula:
10(C/W)(rU / rS)
in which C is the concentration, in µg per mL, of benzene in the Standard solution; W is the weight, in mg, of Carbomer 934 taken to prepare the Test solution; and rU and rS are the benzene peak responses obtained from the Test solution and the Standard solution, respectively: not more than 0.5% is found.
Other requirements— It meets the requirements for Identification, Loss on drying, Heavy metals, and Assay for carboxylic acid content under Carbomer 934P.
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
USP35–NF30 Page 1728
Pharmacopeial Forum: Volume No. 34(1) Page 131