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Pyridoxine Hydrochloride Tablets
» Pyridoxine Hydrochloride Tablets contain not less than 95.0 percent and not more than 115.0 percent of the labeled amount of C8H11NO3·HCl.
Packaging and storage— Preserve in well-closed containers, protected from light.
Identification— To a quantity of powdered Tablets, equivalent to about 100 mg of pyridoxine hydrochloride, add about 5 mL of water. Shake the mixture, filter into a test tube, and add 2 or 3 drops of ferric chloride TS: an orange to deep red color is produced.
Dissolution, Procedure for a Pooled Sample 711—
Medium: water; 900 mL.
Apparatus 2: 50 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C8H11NO3·HCl dissolved employing the procedure set forth in the Assay for niacin or niacinamide, pyridoxine hydrochloride, riboflavin, and thiamine under Water-Soluble Vitamins Tablets by 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 Pyridoxine Hydrochloride RS in the same medium.
Tolerances— Not less than 75% (Q) of the labeled amount of C8H11NO3·HCl is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Procedure for content uniformity— Transfer 1 Tablet, previously finely powdered, to a 500-mL volumetric flask containing about 300 mL of water, shake for about 30 minutes, and dilute with water to volume. Filter a portion of the mixture, discarding the first 25 mL of the filtrate. Dilute a suitable aliquot of the subsequent filtrate quantitatively and stepwise with dilute hydrochloric acid (1 in 100) so that the concentration of pyridoxine hydrochloride is about 10 µg per mL. Dissolve an accurately weighed quantity of USP Pyridoxine Hydrochloride RS in dilute hydrochloric acid (1 in 100), and dilute quantitatively and stepwise with the same solvent to obtain a Standard solution having a known concentration of about 10 µg per mL. Concomitantly determine the absorbances of both solutions in 1-cm cells at the wavelength of maximum absorbance at about 290 nm, with a suitable spectrophotometer, using dilute hydrochloric acid (1 in 100) as the blank. Calculate the quantity, in mg, of C8H11NO3·HCl in the Tablet taken by the formula:
(T / D)C(AU / AS),
in which T is the labeled quantity, in mg, of pyridoxine hydrochloride in the Tablet, D is the dilution factor, C is the concentration, in µg per mL, of USP Pyridoxine Hydrochloride RS in the Standard solution, and AU and AS are the absorbances of the solution from the Tablet and the Standard solution, respectively.
Residual solvents 467: meet the requirements.
(Official January 1, 2007)
Assay— Weigh and finely powder not less than 20 Tablets. Weigh accurately a portion of the powder, equivalent to about 10 mg of pyridoxine hydrochloride, and transfer, with the aid of water, to a conical flask. Add 5 mL of hydrochloric acid, then dilute with water to about 250 mL, and heat on a steam bath until disintegration is complete. Cool, transfer to a 1000-mL volumetric flask, dilute with water to volume, mix, and centrifuge a portion of the mixture. Using the clear supernatant as the Assay preparation, proceed as directed in the Assay under Pyridoxine Hydrochloride Injection, calculating the quantity, in mg, of C8H11NO3·HCl in the portion of Tablets taken by the formula:
C(AU AU¢) / (AS AS¢),
in which C is the concentration, in µg per mL, of USP Pyridoxine Hydrochloride RS in the Standard preparation, and the other terms are as defined therein.
Auxiliary Information— Staff Liaison : Lawrence Evans, III, Ph.D., Scientist
Expert Committee : (DSN05) Dietary Supplements - Non-Botanicals
USP29–NF24 Page 1871
Pharmacopeial Forum : Volume No. 30(1) Page 177
Phone Number : 1-301-816-8389