Cetylpyridinium Chloride Topical Solution
» Cetylpyridinium Chloride Topical Solution contains not less than 95.0 percent and not more than 105.0 percent of the labeled amount of C21H38ClN·H2O.
Packaging and storage— Preserve in tight containers.
A: Dilute a volume of Topical Solution to a concentration of about 40 µg of cetylpyridinium chloride per mL: the UV absorption spectrum of the resulting solution exhibits maxima and minima at the same wavelengths as that of a similar solution of USP Cetylpyridinium Chloride RS, concomitantly measured.
B: Evaporate a volume of Topical Solution, equivalent to about 500 mg of cetylpyridinium chloride, on a steam bath to one-half of its original volume: the resulting solution meets the requirements of Identification test C under Cetylpyridinium Chloride.
Assay— Transfer a volume of Topical Solution, equivalent to about 150 mg of cetylpyridinium chloride, to a glass-stoppered, 500-mL graduated cylinder, and proceed as directed in the Assay under Cetylpyridinium Chloride, beginning with “Add 10 mL of chloroform.” Each mL of 0.02 M sodium tetraphenylboron is equivalent to 7.160 mg of C21H38ClN·H2O.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Behnam Davani, Ph.D., M.B.A.
Senior Scientist
(MDAA05) Monograph Development-Antivirals and Antimicrobials
Reference Standards Lili Wang, Technical Services Scientist
USP32–NF27 Page 1882