Magnesium Gluconate (mag nee' zee um gloo' koe nate). C12H22MgO14·2H2O 450.64 d-Gluconic acid, magnesium salt (2:1), hydrate; Magnesium d-gluconate (1:2) hydrate; Magnesium d-gluconate (1:2) dihydrate [59625-89-7]. Anhydrous [3632-91-5]. DEFINITION Magnesium Gluconate contains NLT 98.0% and NMT 102.0% of anhydrous magnesium gluconate (C12H22MgO14), calculated on the anhydrous basis. IDENTIFICATION • A. Identification TestsGeneral, Magnesium 191: A 100-mg/mL solution meets the requirements. • B. Thin-Layer Chromatography Standard solution: 10 mg/mL of USP Potassium Gluconate RS Sample solution: 10 mg/mL of Magnesium Gluconate, heating in a water bath at 60, if necessary, to dissolve Chromatographic system Mode: TLC Adsorbent: 0.25-mm layer of chromatographic silica gel Application volume: 5 µL Developing solvent system: Alcohol, ethyl acetate, ammonium hydroxide, and water (50:10:10:30) Spray reagent: Dissolve 2.5 g of ammonium molybdate in 50 mL of 2 N sulfuric acid in a 100-mL volumetric flask, add 1.0 g of ceric sulfate, swirl to dissolve, and dilute with 2 N sulfuric acid to volume. Analysis Samples: Standard solution and Sample solution Develop the chromatogram until the solvent front has moved about three-fourths of the length of the plate. Remove the plate from the chamber, and dry at 110 for 20 min. Allow to cool, and spray with the Spray reagent. Heat the plate at 110 for about 10 min. Acceptance criteria: The principal spot of the Sample solution corresponds in color, size, and RF value to that of the Standard solution. ASSAY • Procedure Sample: 800 mg of Magnesium Gluconate Blank: 20 mL of water Titrimetric system (See Titrimetry 541.) Mode: Direct titration Titrant: 0.05 M edetate disodium VS Endpoint detection: Visual Analysis: Dissolve the Sample in 20 mL of water. Add 5 mL of ammoniaammonium chloride buffer TS and 0.1 mL of eriochrome black TS. Titrate with Titrant to a blue endpoint. Perform the Blank determination. Calculate the percentage of magnesium gluconate (C12H22MgO14) in the Sample taken: Result = {[(VS VB) × M × F ]/W} × 100]
Acceptance criteria: 98.0%102.0% on the anhydrous basis IMPURITIES • Chloride and Sulfate, Chloride 221 Standard solution: 0.7 mL of 0.020 N hydrochloric acid Sample: 1.0 g Acceptance criteria: NMT 0.05% • Chloride and Sulfate, Sulfate 221 Standard solution: 1.0 mL of 0.020 N sulfuric acid Sample: 2.0 g Acceptance criteria: NMT 0.05% • Heavy Metals 231 Test preparation: 1.0 g in 10 mL of water. Add 6 mL of 3 N hydrochloric acid, and dilute with water to 25 mL. Acceptance criteria: NMT 20 ppm • Reducing Substances Sample: 1.0 g of Magnesium Gluconate Blank: 10 mL of water Titrimetric system (See Titrimetry 541.) Mode: Residual titration Titrant: 0.1 N iodine VS Back titrant: 0.1 N sodium thiosulfate VS Endpoint detection: Visual Analysis: Transfer the Sample to a 250-mL conical flask, dissolve in 10 mL of water, and add 25 mL of alkaline cupric citrate TS. Cover the flask, boil gently for 5 min, accurately timed, and cool rapidly to room temperature. Add 25 mL of 0.6 N acetic acid, 10.0 mL of Titrant, and 10 mL of 3 N hydrochloric acid, and titrate with Back titrant, adding 3 mL of starch TS as the endpoint is approached. Perform the Blank determination. Calculate the percentage of reducing substances (as dextrose) in the Sample taken: Result = {[(VB VS) × N × F]/W} × 100
Acceptance criteria: NMT 1.0% SPECIFIC TESTS • Water Determination, Method Ib 921 Test preparation: Proceed as directed in the chapter. Allow 30 min for solubilization of Magnesium Gluconate and for the reaction to reach completion. Blank: Use the same volume of Reagent as that of the Test preparation but without the specimen. Analysis Samples: Test preparation and Blank Calculate the water content, in mg, of the Magnesium Gluconate taken: Result = F × (XB X) × R
The other terms are as defined in Water Determination, Method Ib 921. Acceptance criteria: 3.0%12.0% ADDITIONAL REQUIREMENTS • Packaging and Storage: Preserve in well-closed containers. Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 3748 Chromatographic Column Chromatographic columns text is not derived from, and not part of, USP 35 or NF 30. |