Magnesium Gluconate USP Grade Specifications
C12H22MgO14xH2O -- (anhydrous) 414.60
D-Gluconic acid, magnesium salt (2:1), hydrate.
Magnesium D-gluconate (1:2) dihydrate 450.64 --- CAS 59625-89-7.
Anhydrous --- CAS 3632-91-5.

Magnesium Gluconate contains not less than 98.0 percent and not more than 102.0 percent of C12H22MgO14, calculated on the anhydrous basis.

Identification:
A: A solution (1 in 10) responds to the tests for Magnesium.
B: Chromatographic plate test.
pH: between 6.0 and 7.8, in a solution (1 in 20).
Water: between 3.0% and 12.0%.
Chloride: A 1.0-g portion shows no more chloride than corresponds to 0.70 mL of 0.020 N hydrochloric acid (0.05%).
Sulfate: A 2.0-g portion shows no more sulfate than corresponds to 1.0 mL of 0.020 N sulfuric acid (0.05%).
Heavy metals: the limit is 0.002%.
Reducing substances: the limit is 1.0%.

DEFINITION
Anhydrous or hydrated magnesium bis[(2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanoate] (anhydrous or hydrated magnesium di(D-gluconate)).
Content: 98.0 per cent to 102.0 per cent (anhydrous substance).

CHARACTERS
Appearance: White or almost white, amorphous, hygroscopic, crystalline or granular powder.
Solubility: Freely soluble in water, slightly soluble in ethanol (96 per cent), very slightly soluble in methylene chloride.

IDENTIFICATION
A. Thin-layer chromatography.
B. To 10 mL of solution S add 3 mL of ammonium chloride solution. A slight opalescence may be observed. Add 10 mL of disodium hydrogen phosphate solution. A white precipitate is formed that does not dissolve upon the addition of 2 mL of dilute ammonia.

TESTS
Solution S: Dissolve 1.0 g in water and dilute to 50 mL with the same solvent.
Appearance of solution: Solution S is clear and not more intensely coloured than the reference solution.
Sucrose and reducing sugars: Dissolve 0.5 g in a mixture of 2 mL of hydrochloric acid and 10 mL of water. Boil for 5 minutes, allow to cool, add 10 mL of sodium carbonate solution and allow to stand for 10 min. Dilute to 25 mL with water and filter. To 5 mL of the filtrate add 2 mL of cupri-tartaric solution and boil for 1 minute. Allow to stand for 2 minutes. No red precipitate is formed.
Chlorides: Maximum 500 ppm.
Sulfates: Maximum 500& ppm.
Water: Maximum 12 per cent, determined on 80 mg.
Microbial contamination:
TAMC: acceptance criterion 1000 CFU/g.
TYMC: acceptance criterion 100 CFU/g.

Magnesium Gluconate FCC Food Grade Specifications
[CH2OH(CHOH)4COO]2Mg
C12H22MgO14 Formula weight, anhydrous 414.60
C12H22MgO14-2H2O Formula weight, dihydrate 450.63
INS: 580 CAS: anhydrous 3632-91-5
CAS: dihydrate 59625-89-7

DESCRIPTION
Magnesium Gluconate occurs as a white to off white powder or granulate. It is anhydrous, the dihydrate, or a mixture of both. It is very soluble in water and is sparingly soluble in alcohol. It is insoluble in ether.

REQUIREMENTS
Identification
A. A 1:20 aqueous solution gives positive tests for Magnesium.
B. Chromatography Test.
Assay: Not less than 98.0% and not more than 102.0% of C12H22MgO14, calculated on the anhydrous basis.
Chloride: Not more than 0.05%.
Lead: Not more than 2 mg/kg.
Reducing Substances: Not more than 1.0%.
Sulfate: Not more than 0.05%.
Water: Between 3.0% and 12.0%.