Ascorbic Acid Tablets
»Ascorbic Acid Tablets contain not less than 90.0percent and not more than 110.0percent of the labeled amount of C6H8O6.
Packaging and storage—
Preserve in tight,light-resistant containers.
Identification—
Triturate a quantity of finely powdered Tablets with sufficient diluted alcohol to make approximately the equivalent of a 1in 50solution of ascorbic acid,filter,and proceed with the following tests:
B:
To 2mLof the filtrate add 4drops of methylene blue TS,and warm to 40
:the deep blue color becomes appreciably lighter or is completely discharged within 3minutes.
:the deep blue color becomes appreciably lighter or is completely discharged within 3minutes.
C:
To 1mLof the filtrate add 15mLof a solution of trichloroacetic acid (1in 20),add about 200mg of activated charcoal,shake the mixture vigorously for 1minute,and filter through a small fluted filter,returning the filtrate,if necessary,until clear.To 5mLof the filtrate add 1drop of pyrrole,and agitate gently until dissolved,then heat in a bath at 50:a blue color develops.
:a blue color develops.
Dissolution,Procedure for a Pooled Sample á711ñ—
Medium:
water;900mL.
Apparatus 2:
50rpm.
Time:
45minutes.
Procedure—
Determine the amount of C6H8O6dissolved,employing the procedure set forth in the Assayand conducting the procedure without delay,making any necessary modifications.
Tolerances—
Not less than 75%(Q)of the labeled amount of C6H8O6is dissolved in 45minutes.
Uniformity of dosage units á905ñ:
meet the requirements.
Assay—
Transfer not less than 20Tablets to a 1000-mLvolumetric flask containing 250mLof metaphosphoric-acetic acids TS.Insert the stopper in the flask,and shake by mechanical means for 30minutes or until the tablets have disintegrated completely.Dilute with water to volume,and mix.Transfer a portion of the solution to a centrifuge tube,and centrifuge until a clear supernatant is obtained.Quantitatively dilute the clear supernatant with water,if necessary,to obtain a solution containing about 500µg of ascorbic acid per mL.Pipet 4mLof the solution,equivalent to about 2mg of ascorbic acid,into a 50-mLconical flask,and proceed as directed in the Assayunder Ascorbic Acid Oral Solution,beginning with “Add 5mLof metaphosphoric-acetic acids TS.”
From the ascorbic acid equivalent of the standard dichlorophenol-indophenol solution,calculate the content of ascorbic acid in each Tablet.
Auxiliary Information—
Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(DSN)Dietary Supplements:Non-Botanicals
USP28–NF23Page 179
Pharmacopeial Forum:Volume No.30(1)Page 60
Phone Number:1-301-816-8389