Thiamine Hydrochloride Tablets
DEFINITION
Thiamine Hydrochloride Tablets contain NLT 90.0% and NMT 110.0% of the labeled amount of thiamine hydrochloride (C12H17ClN4OS·HCl).
IDENTIFICATION
• A.
Sample solution: Triturate a quantity of powdered Tablets, equivalent to 10 mg of thiamine hydrochloride, with 10 mL of 0.5 N sodium hydroxide, and filter.
Analysis: To 5 mL of the Sample solution add 0.5 mL of potassium ferricyanide TS and 5 mL of isobutyl alcohol, shake the mixture vigorously for 2 min, and allow the liquid layers to separate. Illuminate from above by a vertical beam of UV light, and observe the air–liquid meniscus at a right angle to this beam.
Acceptance criteria: The air–liquid meniscus shows a vivid blue fluorescence, which disappears when the mixture is slightly acidified, but reappears when it is again made alkaline.
• B.
Sample solution: Triturate a quantity of powdered Tablets, equivalent to 10 mg of thiamine hydrochloride, with 10 mL of water, and filter.
Analysis 1: To 2 mL of the Sample solution add iodine TS.
Acceptance criteria 1: A red-brown precipitate is formed.
Analysis 2: To 2 mL of the Sample solution add mercuric chloride TS.
Acceptance criteria 2: A white precipitate is formed.
Analysis 3: Identification Tests—General 
191
, Chloride
191, ChlorideAcceptance criteria 3: Meet the requirements
• C.
Sample solution: Use the remainder of the Sample solution from Identification test B.
Analysis: Add 1 mL of lead acetate TS and 1 mL of 2.5 N sodium hydroxide.
Acceptance criteria: A yellow color is produced. Heat the mixture for several min on a steam bath: the color changes to brown, and, on standing, a precipitate of lead sulfide separates.
ASSAY
• Thiamine Assay 531
531 Assay preparation: Place NLT 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 with 0.2 N hydrochloric acid to obtain a 0.2 µg/mL solution of thiamine hydrochloride.
Analysis: Proceed as directed in the chapter.
Acceptance criteria: 90.0%–110.0%
PERFORMANCE TESTS
• Dissolution, Procedure for a Pooled Sample 711
711 Medium: Water; 900 mL
Apparatus 2: 50 rpm
Time: 45 min
Standard solution: A known concentration of USP Thiamine Hydrochloride RS in Medium
Sample solution: Filtered portion of the solution under test, suitably diluted with the Medium if necessary
Mobile phase: A mixture of methanol, glacial acetic acid, and water (27:1:73) containing 1.40 mg/mL of sodium 1-hexanesulfonate
Chromatographic system
Mode: LC
Detector: UV 280 nm
Column: 3.9-mm × 30-cm; packing L1
Flow rate: 1 mL/min
Injection size: 10 µL
System suitability
Sample: Standard solution
Suitability requirements
Relative standard deviation: NMT 3.0%
Analysis
Samples: Standard solution and Sample solution
Calculate the percentage of the labeled amount of thiamine hydrochloride (C12H17ClN4OS·HCl) dissolved:
Result = (rU/rS) × (CS × D × V/L) × 100
| rU | = | = peak area of thiamine from the Sample solution |
| rS | = | = peak area of thiamine from the Standard solution |
| CS | = | = concentration of USP Thiamine Hydrochloride RS in the Standard solution (mg/mL) |
| D | = | = dilution factor for the Sample solution |
| V | = | = volume of Medium, 900 mL |
| L | = | = labeled amount of thiamine hydrochloride (mg/Tablet) |
Tolerances: NLT 75% (Q) of the labeled amount of thiamine hydrochloride (C12H17ClN4OS·HCl) is dissolved.
• Uniformity of Dosage Units 905: Meet the requirements
905: Meet the requirementsADDITIONAL REQUIREMENTS
• Packaging and Storage: Preserve in tight, light-resistant containers.
• USP Reference Standards 11
11 USP Thiamine Hydrochloride RS 
') + '&img=../../images/v35300/cas-67-03-8.gif',600,500);)
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Natalia Davydova Scientific Liaison 1-301-816-8328 | (DS2010) Monographs - Dietary Supplements |
| 711 | Margareth R.C. Marques, Ph.D. Senior Scientific Liaison 1-301-816-8106 | (GCDF2010) General Chapters - Dosage Forms |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 4837
Pharmacopeial Forum: Volume No. 30(1) Page 190