Pyridoxine Hydrochloride Tablets
DEFINITION
Pyridoxine Hydrochloride Tablets contain NLT 95.0% and NMT 115.0% of the labeled amount of pyridoxine hydrochloride (C8H11NO3·HCl).
IDENTIFICATION
• A. Reaction with Ferric Ion
Sample:
Equivalent to 100 mg of pyridoxine hydrochloride from a quantity of powdered Tablets
Analysis:
Add 5 mL of water to the Sample. Shake the mixture, filter into a test tube, and add 2 or 3 drops of ferric chloride TS.
Acceptance criteria:
An orange to deep red color is produced.
ASSAY
• Procedure
Buffer:
Dissolve 16 g of ammonium chloride in 70 mL of water, add 16 mL of ammonium hydroxide, dilute with water to 100 mL, and filter.
Color reagent:
0.4 mg/mL of 2,6-dichloroquinone chlorimide in isopropyl alcohol. [Note—Store the solution in a refrigerator, and use within one month. Do not use the solution if it has become pink. ]
Standard stock solution:
0.1 mg/mL of USP Pyridoxine Hydrochloride RS in 0.1 N hydrochloric acid. [Note—Keep the solution in an amber bottle, in a cool place. ]
Standard solution:
10 µg/mL of USP Pyridoxine Hydrochloride RS from the Standard stock solution diluted with water. [Note—Prepare this solution daily as needed. ]
Sample solution:
Weigh and finely powder NLT 20 Tablets. Transfer, with the aid of water, a portion of the powdered Tablets to a conical flask. Add 0.5 mL hydrochloric acid per each mg of the nominal amount of pyridoxine hydrochloride taken, then dilute with water to about 0.04 mg/mL, and heat on a steam bath until disintegration is complete. Cool, dilute with water to 10 µg/mL, and centrifuge a portion of the mixture.
Instrumental conditions
Mode:
Visible
Analytical wavelength:
650 nm
Blank:
Water
Analysis
Samples:
Standard solution and Sample solution
Separately add 25.0 mL of isopropyl alcohol to 5 mL each of the Standard solution and the Sample solution. Transfer 5 mL of each of the resulting solutions to separate, glass-stoppered, 25-mL graduated cylinders or test tubes, and add in succession, mixing after each addition, 1.0 mL of Buffer, 1.0 mL of a 0.2-g/mL solution of sodium acetate, and 1.0 mL of water. Cool to 25
, add 1.0 mL of Color reagent, and shake vigorously for 10 s, accurately timed. Determine the absorbance 90 s after the addition of the Color reagent. Repeat the procedure both for the Standard solution and the Sample solution, but substitute 1.0 mL of a 50-mg/mL solution of boric acid solution for the 1.0 mL of water.
, add 1.0 mL of Color reagent, and shake vigorously for 10 s, accurately timed. Determine the absorbance 90 s after the addition of the Color reagent. Repeat the procedure both for the Standard solution and the Sample solution, but substitute 1.0 mL of a 50-mg/mL solution of boric acid solution for the 1.0 mL of water.
[Note—Make the reading promptly to avoid errors due to fading of the color. ]
Calculate the percentage of the labeled amount of pyridoxine hydrochloride (C8H11NO3·HCl) in the portion of Tablets taken:
Result = (AU 
AU¢)/(AS AS¢) × (CS/CU) × 100
AU¢)/(AS AS¢) × (CS/CU) × 100| AU | = | = absorbance of Sample solution with water |
| AU¢ | = | = absorbance of Sample solution with boric acid |
| AS | = | = absorbance of Standard solution with water |
| AS¢ | = | = absorbance of Standard solution with boric acid |
| CS | = | = concentration of USP Pyridoxine Hydrochloride RS in the Standard solution (µg/mL) |
| CU | = | = nominal concentration of pyridoxine hydrochloride in the Sample solution (µg/mL) |
Acceptance criteria:
95.0%–115.0%
PERFORMANCE TESTS
• Dissolution, Procedure for a Pooled Sample 
711
711
Medium:
Water; 900 mL
Apparatus 2:
50 rpm
Time:
45 min
Mobile phase:
A mixture of methanol, glacial acetic acid, and water (27:1:73) containing 1.40 mg/mL of sodium 1-hexanesulfonate
Standard solution:
Known concentration of USP Pyridoxine Hydrochloride RS in Medium
Sample solution:
Filtered portion of the solution under test, suitably diluted with Medium if necessary
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 pyridoxine hydrochloride (C8H11NO3·HCl) dissolved:
Result = (rU/rS) × (CS × D × V/L) × 100
| rU | = | = peak area of pyridoxine from the Sample solution |
| rS | = | = peak area of pyridoxine from the Standard solution |
| CS | = | = concentration of USP Pyridoxine Hydrochloride RS in the Standard solution (mg/mL) |
| D | = | = dilution factor for the Sample solution |
| V | = | = volume of Medium, 900 mL |
| L | = | = label claim (mg/Tablet) |
Tolerances:
NLT 75% (Q) of the labeled amount of pyridoxine hydrochloride (C8H11NO3·HCl) is dissolved.
• Uniformity of Dosage Units 905:
Meet the requirements
905:
Meet the requirements
Content uniformity
Standard solution:
10 µg/mL of USP Pyridoxine Hydrochloride RS in dilute hydrochloric acid (1 in 100)
Sample solution:
Transfer 1 Tablet, finely powdered, to a 500-mL volumetric flask containing 300 mL of water, shake for 30 min, and dilute with water to volume. Filter a portion of the mixture, discarding the first 25 mL of the filtrate. Dilute an aliquot of the filtrate with dilute hydrochloric acid (1 in 100) to obtain 10 µg/mL of pyridoxine hydrochloride.
Instrumental conditions
Mode:
UV
Analytical wavelength:
290 nm
Cell:
1 cm
Blank:
Dilute hydrochloric acid (1 in 100)
Analysis
Samples:
Standard solution and Sample solution
Determine the absorbances of the Standard solution and Sample solution.
Calculate the percentage of pyridoxine hydrochloride (C8H11NO3·HCl) in the portion of Tablets taken:
Result = (AU/AS) × (CS/CU) × (100/L)
| AU | = | = absorbance of the Sample solution |
| AS | = | = absorbance of the Standard solution |
| CS | = | = concentration of USP Pyridoxine Hydrochloride RS in the Standard solution (mg/mL) |
| CU | = | = nominal concentration of pyridoxine hydrochloride in the Sample solution (mg/mL) |
| L | = | = label claim (mg/Tablet) |
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in well-closed containers, protected from light.
• USP Reference Standards 11
11
USP Pyridoxine Hydrochloride RS 
') + '&img=../../images/v35300/cas-58-56-0.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 4492
Pharmacopeial Forum: Volume No. 30(1) Page 177