Ferrous Fumarate Tablets
DEFINITION
Ferrous Fumarate Tablets contain NLT 95.0% and NMT 110.0% of the labeled amount of ferrous fumarate (C4H2FeO4).
IDENTIFICATION
• A. Identification Tests—General, Iron 
191
191 Sample solution: To a portion of powdered Tablets, equivalent to 1 g of ferrous fumarate, add 25 mL of dilute hydrochloric acid (1 in 2), mix, and add 25 mL of water. Boil the solution for a few min, cool, and filter.
Acceptance criteria: The filtrate meets the requirements.
ASSAY
• Procedure
Sample: A portion of the powder from NLT 20 finely powdered Tablets equivalent to 500 mg of ferrous fumarate
Blank: Proceed as in the Analysis without the Sample.
Titrimetric system
(See Titrimetry 541.)
541.)Mode: Indirect titration
Titrant: 0.1 N sodium thiosulfate VS
Indicator: Starch TS
Endpoint detection: Visual
Analysis: Transfer the Sample to a 250-mL beaker. Add 25 mL of water, 25 mL of nitric acid, and 7.5 mL of perchloric acid. Cover with a ribbed watch glass, and heat to the production of strong fumes. Cool, rinse the watch glass and the sides of the beaker with water, and evaporate in a hood to near-dryness. Wash down the watch glass and the sides of the beaker with 2 mL of hydrochloric acid and then with a small volume of water. Warm slightly, if necessary, to dissolve the residue. Transfer to a glass-stoppered, 250-mL conical flask. Repeat the washing with 2 mL of hydrochloric acid, and complete the transfer to the flask, using NMT 20–25 mL of water for the transfer. Add 4 g of potassium iodide to the flask, insert the stopper, and allow to stand in the dark for 5 min. Add 75 mL of water and titrate with Titrant, adding 3 mL of starch TS as the endpoint is approached. Perform a blank determination.
Calculate the percentage of the labeled amount of ferrous fumarate (C4H2FeO4) in the portion of Tablets taken:
Result = {[(VS 
VB) × N × F]/W} × 100
VB) × N × F]/W} × 100| VS | = | = Titrant volume consumed by the Sample (mL) |
| VB | = | = Titrant volume consumed by the Blank (mL) |
| N | = | = actual normality of the Titrant (mEq/mL) |
| F | = | = equivalency factor, 169.9 mg/mEq |
| W | = | = nominal weight of ferrous fumarate in the Sample taken (mg) |
Acceptance criteria: 95.0%–110.0%
PERFORMANCE TESTS
• Dissolution 711
711 Medium: 0.1 N hydrochloric acid in 0.5% sodium lauryl sulfate; 900 mL
Apparatus 2: 75 rpm
Time: 45 min
Standard solution: Solution having a known concentration of iron in the Medium
Sample solution: Filtered portion of the solution under test, suitably diluted with the Medium if necessary
Instrumental conditions
Mode: Atomic absorption spectrophotometry
Analytical wavelength: 248.3 nm
Lamp: Iron hollow-cathode
Flame: Air–acetylene
Analysis
Samples: Standard solution and Sample solution
Determine the concentration of iron (Fe) in the Sample solution in comparison with a Standard solution.
Calculate the percentage of the labeled amount of ferrous fumarate (C4H2FeO4) dissolved:
Result = (Mr/Ar) × (C × D × V/L) × 100
| Mr | = | = molecular weight of ferrous fumarate, 169.9 |
| Ar | = | = atomic weight of iron, 55.85 |
| C | = | = measured concentration of iron in the Sample solution (mg/mL) |
| D | = | = dilution factor for the Sample solution |
| V | = | = volume of Medium, 900 mL |
| L | = | = label amount of ferrous fumarate (mg/Tablet) |
Tolerances: NLT 75% (Q) of the labeled amount of ferrous fumarate is dissolved.
• Uniformity of Dosage Units 905: Meet the requirements
905: Meet the requirementsADDITIONAL REQUIREMENTS
• Packaging and Storage: Preserve in tight containers.
• Labeling: Label the Tablets in terms of ferrous fumarate (C4H2FeO4) and in terms of elemental iron.
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 |
USP35–NF30 Page 3173