Ferrous Ascorbate
C12H14FeO12 Mol. Wt. 406.1
Ferrous Ascorbate is (2R)-2-[(1S)-1,2-dihydroxyethyl]-4,5dihydroxyfuran-3-one;iron (2+).
Ferrous Ascorbate contains not less than 14.0 per cent and not more than 16.0 per cent of Ferrous Iron and not less than 73.0 per cent and not more than 77.0 per cent of Ascorbic acid, calculated on the dried basis.
Category. Haematinic.
Dose. 100 mg daily.
Description. A fine, dark violet coloured dried powder.
Identification
- It gives reaction A of ferrous salts (2.3.1).
- Dissolve 100 mg sample in 10 ml ofwaterand add 1 ml of 0.05 M sulphuric acid, 1 ml of 2,6-dichlorophenolindophenol solution, add 1 ml of dinitrophenyl hydrazine solution. Mix the solutions and keep in boiling water bath for 10 minutes. The solution gives orange-red colour.
Tests
Appearance of Solution. Dissolve 1.0 g of the substance under examination in 100 ml of 1 M hydrochloric acid. The solution is clear and almost colourless or pale yellow.
pH (2.4.24). 5.5 to 6.5 determined in a 1.0 per cent w/v solution in water.
Loss on drying (2.4.19). Not more than 10.0 per cent, determined on 1.0 g by drying in an oven at 105°.
Sulphated ash (2.3.18). 21.0 per cent to 24.0 per cent, determined on 1.0 g.
Ferric Iron Content. Not more than 1.0 per cent, determined by the following method.
Transfer about 5.0 g in to a glass stoppered flask and dissolve in a mixture of 100.0 ml of freshly boiled and cooled water and 10.0 ml of hydrochloric acid. Add 3 g of potassium iodide. Shake well and allow to stand in the dark for 5 minutes. Titrate the liberated iodine with 0.1 M sodium thiosulphate using starch solution, added towards the end of the titration, as indicator. Repeat the analysis without substance under examination. The difference between the titrations represents the amount of iodine liberated by the ferric iron.
1 ml of 0.1 M sodium thiosulphate is equivalent to 0.005585 g of ferric iron.
Assay.
Ferrous Iron
Test solution. Weigh 0.2 g of sample in a 100.0 ml volumetric flask. Dissolve in water, add 8.0 ml of acetic acid and make up the volume with water. Dilute 10.0 ml of this solution to 100.0 ml with water.
Reference solution. Weigh 0.2 g of ferrous ammonium sulphate in a 100.0 ml volumetric flask. Dissolve in water add 8.0 ml of acetic acid and make up volume with water. Dilute 10.0 ml of this solution to 100.0 ml with the water.
Transfer 5.0 ml of reference solution and the test solution separating in 100.0 ml volumetric flask, add 20 ml of water and 2.0 ml of phenanthroline solution. Mix well and dilute to volume with water. Measure the absorbance after 1 hour at 515 nm (2.4.7). Calculate the content of ferrous iron.
Ascorbic acid
Weigh 0.15 g add 25.0 ml of 0.2 M disodium edetate solution, 1.0 ml of 20.0 per cent w/v solution of citric acid solution, and add 0.5 ml starch solution as indicator. Titrate with 0.05M iodine until a persistent blue colour is obtained.
1 ml of 0.05 M iodine is equivalent to 0.008806 g of C6H8O6.
Storage: Store protected from light and moisture
Solubility: Freely soluble in water, insoluble in organic solvent