Niacinamide Tablets
» Niacinamide Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C6H6N2O.
Packaging and storage— Preserve in tight containers.
A: Extract a quantity of powdered Tablets, equivalent to about 500 mg of niacinamide, with two 10-mL portions of alcohol, evaporate the filtered alcohol extracts on a steam bath, and dry at 80 for 2 hours: the IR absorption spectrum of a potassium bromide dispersion of the residue so obtained exhibits maxima only at the same wavelengths as that of a similar preparation of USP Niacinamide RS.
B: From the niacinamide obtained in Identification test A, prepare a solution (1 in 50,000), and determine the absorbance of this solution in a 1-cm cell at 245 nm and at 262 nm, with a suitable spectrophotometer, using water as the blank: the ratio A245/A262 is between 0.63 and 0.67.
Dissolution, Procedure for a Pooled Sample 711
Medium: water; 900 mL.
Apparatus 2: 50 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C6H6N2O dissolved, employing the procedure set forth in the Assay for niacin or niacinamide, pyridoxine hydrochloride, riboflavin, and thiamine under Water-soluble Vitamins Tablets, using filtered portions of the solution under test, suitably diluted with Dissolution Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Niacinamide RS in the same medium.
Tolerances— Not less than 75% (Q) of the labeled amount of C6H6N2O is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Assay— Proceed with Tablets as directed for Chemical Method under Niacin or Niacinamide Assay 441, using Standard Niacinamide Preparation as the Standard Preparation in the Assay Procedure: and the following as the Assay Preparation. Weigh and finely powder not less than 10 Tablets. Weigh accurately a quantity of the powder, equivalent to about 25 mg of niacinamide, and transfer with the aid of about 50 mL of water to a 250-mL volumetric flask. Heat, if necessary, until no more dissolves, cool, dilute with water to volume, and mix. Pipet 10 mL of the solution into a 100-mL volumetric flask, dilute with water to volume, and mix. Calculate the quantity, in mg, of C6H6N2O in the portion of Tablets taken by the formula:
25(AU / AS).
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Curtis Phinney

(DSN05) Dietary Supplements - Non-Botanicals
Reference Standards Lili Wang, Technical Services Scientist
711 Margareth R.C. Marques, Ph.D.
Senior Scientist
(BPC05) Biopharmaceutics05
USP32–NF27 Page 3078
Pharmacopeial Forum: Volume No. 30(1) Page 139