Methylbenzethonium Chloride Topical Powder
» Methylbenzethonium Chloride Topical Powder contains not less than 85.0 percent and not more than 115.0 percent of the labeled amount of methylbenzethonium chloride (C28H44ClNO2·H2O) in a suitable fine powder base, free from grittiness.
Packaging and storage Preserve in well-closed containers.
Identification Suspend about 0.1 g in 10 mL of water, add 0.1 g of sodium carbonate, 1 mL of bromophenol blue TS, and 10 mL of chloroform, and shake the mixture: the chloroform layer is blue.
pH 791: between 9.0 and 10.5, in a dispersion of it in carbon dioxide-free water (1 in 100).
Other tests Not less than 99% of it passes through a No. 200 sieve (see Powder Fineness 811).
0.0001 N Docusate sodium Prepare as directed for 0.0001 N Docusate sodium in the Assay under Methylbenzethonium Chloride Lotion.
Procedure Transfer an accurately weighed portion of Topical Powder, equivalent to about 0.5 mg of methylbenzethonium chloride, to a glass-stoppered, 50-mL cylinder, and proceed as directed in the Assay under Methylbenzethonium Chloride Lotion, beginning with Add 5 mL of chloroform.
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP32NF27 Page 2938Pharmacopeial Forum: Volume No. 30(2) Page 516