Thiamine Hydrochloride Tablets
» Thiamine Hydrochloride Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C12H17ClN4OS·HCl.
Packaging and storage— Preserve in tight, light-resistant containers.
Identification—
A: Triturate a quantity of powdered Tablets, equivalent to about 10 mg of thiamine hydrochloride, with 10 mL of 0.5 N sodium hydroxide, and filter. Using a 5-mL portion of the filtrate, proceed as directed in Identification test B under Thiamine Hydrochloride Injection, beginning with “then add 0.5 mL of potassium ferricyanide TS”: the specified reaction is observed.
B: Triturate a quantity of powdered Tablets, equivalent to about 10 mg of thiamine hydrochloride, with 10 mL of water, and filter: treated separately, 2-mL portions of the filtrate yield a red-brown precipitate with iodine TS and a white precipitate with mercuric chloride TS, and respond to the tests for Chloride 191.
C: To the remainder of the filtrate prepared for the preceding test add 1 mL of lead acetate TS and 1 mL of 2.5 N sodium hydroxide: a yellow color is produced. Heat the mixture for several minutes on a steam bath: the color changes to brown, and, on standing, a precipitate of lead sulfide separates.
Dissolution, Procedure for a Pooled Sample 711
Medium: water; 900 mL.
Apparatus 2: 50 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C12H17ClN4OS·HCl dissolved, employing the procedure set forth in the Assay for niacin or niacinamide, pyridoxine hydrochloride, riboflavin, and thiamine, Method 1 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 Thiamine Hydrochloride RS in the same Medium.
Tolerances— Not less than 75% (Q) of the labeled amount of C12H17ClN4OS·HCl is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Assay—
Standard preparation— Prepare as directed for Standard Preparation under Thiamine Assay 531.
Assay preparation— Place not fewer than 20 Tablets in a flask of suitable size, half fill the flask with 0.2 N hydrochloric acid, and heat on a steam bath, with frequent agitation, until the tablets have dissolved or have disintegrated so that a uniform dispersion is obtained. Cool, transfer the contents of the flask to a volumetric flask, and dilute with 0.2 N hydrochloric acid to volume. If the mixture is not clear, either centrifuge it or filter it through paper known not to adsorb thiamine. Dilute a portion of the clear solution quantitatively and stepwise with 0.2 N hydrochloric acid to obtain a solution containing about 0.2 µg of thiamine hydrochloride per mL. Using this as the Assay Preparation, proceed as directed for Procedure under Thiamine Assay 531.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Curtis Phinney

1-301-816-8540
(DSN05) Dietary Supplements - Non-Botanicals
Reference Standards Lili Wang, Technical Services Scientist
1-301-816-8129
RSTech@usp.org
711 Margareth R.C. Marques, Ph.D.
Senior Scientist
1-301-816-8106
(BPC05) Biopharmaceutics05
USP32–NF27 Page 3719
Pharmacopeial Forum: Volume No. 30(1) Page 190