Methylbenzethonium Chloride Topical Powder
»Methylbenzethonium Chloride Topical Powder contains not less than 85.0percent and not more than 115.0percent 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 0.1g in 10mLof water,add 0.1g of sodium carbonate,1mLof bromophenol blue TS,and 10mLof chloroform,and shake the mixture:the chloroform layer is blue.
pHá791ñ: between 9.0and 10.5,in a dispersion of it in carbon dioxide-free water (1in 100).
Other tests— Not less than 99%of it passes through a No.200sieve (see Powder Fineness á811ñ).
Assay—
0.0001N Docusate sodium— Prepare as directed for 0.0001N Docusate sodiumin the Assayunder Methylbenzethonium Chloride Lotion.
Procedure— Transfer an accurately weighed portion of Topical Powder,equivalent to about 0.5mg of methylbenzethonium chloride,to a glass-stoppered,50-mLcylinder,and proceed as directed in the Assayunder Methylbenzethonium Chloride Lotion,beginning with “Add 5mLof chloroform.”
Auxiliary Information— Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1257
Pharmacopeial Forum:Volume No.30(2)Page 516
Phone Number:1-301-816-8394