Phenazopyridine Hydrochloride Tablets
»Phenazopyridine Hydrochloride Tablets contain not less than 90.0percent and not more than 110.0percent of the labeled amount of phenazopyridine hydrochloride (C11H11N5·HCl).
Packaging and storage—
Preserve in tight containers.
Identification—
Transfer a quantity of finely ground Tablets,equivalent to about 50mg of phenazopyridine hydrochloride,to a 125-mLseparator,add 50mLof water,1mLof 1Nhydrochloric acid,and 5mLof a saturated sodium chloride solution,and shake to dissolve.Extract with two 25-mLportions of chloroform,and discard the chloroform.Add 5mLof 1Nsodium hydroxide to the aqueous solution,and extract with one 50-mLportion of chloroform.Transfer the chloroform layer to a second 125-mLseparator,and wash with one 50-mLportion of 0.1Nsodium hydroxide.Filter the chloroform layer through a pledget of cotton previously washed with chloroform.Add 5drops of hydrochloric acid to the filtrate,and evaporate under a current of air on a steam bath to dryness.Add 5mLof alcohol,and evaporate.Dry the residue at 105
for 4hours:the IRabsorption spectrum of a potassium bromide dispersion of the dried residue so obtained exhibits maxima only at the same wavelengths as that of a similar preparation of USP Phenazopyridine Hydrochloride RS.
for 4hours:the IRabsorption spectrum of a potassium bromide dispersion of the dried residue so obtained exhibits maxima only at the same wavelengths as that of a similar preparation of USP Phenazopyridine Hydrochloride RS.
Dissolution á711ñ—
Medium:
water;900mL.
Apparatus 2:
50rpm.
Time:
45minutes.
Procedure—
Determine the amount of C11H11N5·HCl dissolved from UVabsorbances at the wavelength of maximum absorbance at about 422nm on filtered portions of the solution under test,suitably diluted with Dissolution Mediumin comparison with a Standard solution having a known concentration of USP Phenazopyridine Hydrochloride RSin the same Medium.
Tolerances—
Not less than 75%(Q)of the labeled amount of C11H11N5.HCl is dissolved in 45minutes.
Uniformity of dosage units á905ñ:
meet the requirements.
Assay—
Phosphate buffer—
Dissolve 2.64g of dibasic ammonium phosphate in about 900mLof water.Adjust with phosphoric acid to a pHof 3.0,dilute with water to 1000mL,and mix.
Mobile phase—
Prepare a mixture of Phosphate bufferand methanol (50:50).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Standard preparation—
Transfer about 50mg of USP Phenazopyridine Hydrochloride RS,accurately weighed,to a 100-mLvolumetric flask.Add 50mLof methanol,and swirl to dissolve.Dilute with Phosphate bufferto volume,mix,and pass through a filter having a 0.5-µm or finer porosity.
Assay preparation—
Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 100mg of phenazopyridine hydrochloride,to a 200-mLvolumetric flask.Add 100mLof methanol,and sonicate for 10minutes.Add about 75mLof Phosphate buffer,and sonicate for an additional 10minutes,with occasional mixing.Dilute with Phosphate bufferto volume,and mix.Pass this solution through a filter having a 0.5-µm or finer porosity.
Chromatographic system (see Chromatography á621ñ)—
The liquid chromatograph is equipped with a 220-nm detector and a 3.9-mm ×30-cm column that contains packing L1.The flow rate is about 1.5mLper minute.Chromatograph the Standard preparation,and record the responses as directed for Procedure:the column efficiency is not less than 1400theoretical plates;the tailing factor for the analyte peak is not more than 2.0;and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure—
Separately inject equal volumes (about 10µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of C11H11N5.HCl in the portion of Tablets taken by the formula:
200C(rU/rS),
in which Cis the concentration,in mg per mL,of USP Phenazopyridine Hydrochloride RSin the Standard preparation;and rUand rSare the phenazopyridine peak responses obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information—
Staff Liaison:Daniel K.Bempong,Ph.D.,Scientist
Expert Committee:(PA2)Pharmaceutical Analysis 2
USP28–NF23Page 1525
Phone Number:1-301-816-8143