Packaging and storage— Preserve in collapsible tubes or in tight containers,preferably at controlled room temperature.

Identification— Filter 5mLof the solution obtained by titration in the Assay.Add 1mLof ferric chloride TSto the filtrate:a violet color is produced.Add 1mLof 6Nacetic acid:the violet color does not change.Add 1mLof 6Nhydrochloric acid:the violet color is discharged.Asmall amount of white precipitate may appear.

Alcohol content (if present)á611ñ: from 90.0%to 110.0%of the labeled amount of C2H5OH.

Assay— To 25mLof diluted alcohol add 1drop of phenolphthalein TSand sufficient 0.1Nsodium hydroxide to produce a faint pink color.Add 5.0g of Gel,accurately weighed,and stir.Titrate the dispersion with 0.1Nsodium hydroxide VSuntil a pink color is produced.[NOTE—Reserve this solution for the Identification test.]Each mLof 0.1Nsodium hydroxide is equivalent to 13.81mg of C7H6O3.

Expert Committee:(PA6)Pharmaceutical Analysis 6

USP28–NF23Page 1748

Phone Number:1-301-816-8389