Ferrous Sulfate Tablets
»Ferrous Sulfate Tablets contain not less than 95.0percent and not more than 110.0percent of the labeled amount of ferrous sulfate (FeSO4·7H2O).
NOTE—An equivalent amount of Dried Ferrous Sulfate may be used in place of FeSO4·7H2Oin preparing Ferrous Sulfate Tablets.
Packaging and storage— Preserve in tight containers.
Labeling— Label the Tablets in terms of ferrous sulfate (FeSO4·7H2O)and in terms of elemental iron.
Identification— Dissolve a quantity of powdered Tablets,equivalent to about 250mg of ferrous sulfate,in sufficient water,acidified with hydrochloric acid,to make 25mLof solution:the solution responds to the tests for Ferrous Salts á191ñand for Sulfate á191ñ.
Dissolution á711ñ—
Medium: 0.1Nhydrochloric acid;900mL.
Apparatus 2: 50rpm.
Time: 45minutes.
Procedure— Determine the amount of FeSO4·7H2Odissolved,employing atomic absorption spectrophotometry at a wavelength of about 248.3nm on filtered portions of the solution under test,suitably diluted with Dissolution Mediumif necessary,in comparison with a Standard solution having a known concentration of iron in the same medium.
Tolerances— Not less than 75%(Q)of the labeled amount of FeSO4·7H2Ois dissolved in 45minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Assay— Weigh and finely powder not fewer than 20Tablets.Dissolve a portion of the powder,equivalent to about 500mg of ferrous sulfate and accurately weighed,in a beaker containing a mixture of 20mLof 2Nsulfuric acid and 80mLof freshly boiled and cooled water.Filter the solution rapidly as soon as all soluble ingredients in the tablets are dissolved,and wash the container and the filter with small portions of a mixture of 20mLof 2Nsulfuric acid and 80mLof freshly boiled and cooled water.Add orthophenanthroline TS,and immediately titrate the combined filtrate and washings with 0.1Nceric sulfate VS.Each mLof 0.1Nceric sulfate is equivalent to 27.80mg of ferrous sulfate (FeSO4·7H2O).
Auxiliary Information— Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(DSN)Dietary Supplements:Non-Botanicals
USP28–NF23Page 822
Phone Number:1-301-816-8389