(Ph. Eur. monograph 0979)
C12H22CaO14,H2O 448.4 18016-24-5
Action and use
Used in treatment of calcium deficiency.
Preparation
Calcium Gluconate Injection
DEFINITION
Calcium bis[(2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanoate] monohydrate (calcium di(D-gluconate) monohydrate).
Content
99.0 per cent to 101.0 per cent of C12H22CaO14,H2O.
CHARACTERS
Appearance
White or almost white, crystalline or granular powder.
Solubility
Sparingly soluble in water, freely soluble in boiling water.
IDENTIFICATION
A. Thin-layer chromatography (2.2.27).
Test solution: Dissolve 20 mg of the substance to be examined in 1 mL of water R, heating if necessary in a water-bath at 60 °C.
Reference solution: Dissolve 20 mg of calcium gluconate CRS in 1 mL of water R, heating if necessary in a water-bath at 60 °C.
Plate: TLC silica gel plate R (5-40 μm) [or TLC silica gel plate R (2-10 μm)].
Mobile phase: concentrated ammonia R, ethyl acetate R, water R, ethanol (96 per cent) R (10:10:30:50 V/V/V/V).
Application: 1 μL.
Development: Over 2/3 of the plate.
Drying: At 100 °C for 20 min; allow to cool.
Detection: Spray with a solution containing 10 g/L of cerium sulfate R and 25 g/L of ammonium molybdate R in dilute sulfuric acid R and heat at 105 °C for about 10 min.
Results: After 5 min, the principal spot in the chromatogram obtained with the test solution is similar in position, colour and size to the principal spot in the chromatogram obtained with the reference solution.
B. About 20 mg gives reaction (b) of calcium (2.3.1).
TESTS
Solution S
To 10.0 g add 90 mL of boiling distilled water R and boil with stirring, for not more than 10 s, until completely dissolved, then dilute to 100.0 mL with the same solvent.
Appearance of solution
At 60 °C, solution S is not more intensely coloured than reference solution B7 (2.2.2, Method II). After cooling to 20 °C, it is not more opalescent than reference suspension II (2.2.1).
pH (2.2.3)
6.4 to 8.3.
Dissolve 1.0 g in 20 mL of carbon dioxide-free water R, heating on a water-bath.
Organic impurities and boric acid
Introduce 0.5 g into a porcelain dish previously rinsed with sulfuric acid R and placed in a bath of iced water. Add 2 mL of cooled sulfuric acid R and mix. No yellow or brown colour develops. Add 1 mL of chromotrope II B solution R. A violet colour develops and does not become dark blue. The solution is not more intensely coloured than that of a mixture of 1 mL of chromotrope II B solution R and 2 mL of cooled sulfuric acid R.
Oxalates
Liquid chromatography (2.2.29).
Solvent mixture: Dilute 1 mL of hydrochloric acid R to 1200 mL with water for chromatography R.
Test solution: Dissolve 0.200 g of the substance to be examined in the solvent mixture using sonication and dilute to 10.0 mL with the solvent mixture.
Reference solution (a): Dilute 2.0 mL of a 0.152 g/L solution of sodium oxalate R to 100.0 mL with the solvent mixture.
Reference solution (b): Mix 2 mL of a 0.152 g/L solution of sodium oxalate R, 20 mL of sulfate standard solution (10 ppm SO4) R and 50 mL of water for chromatography R, and dilute to 100 mL with water for chromatography R.
Precolumn:
— size: l = 50 mm, Ø = 4 mm;
— stationary phase: strongly basic anion-exchange resin for chromatography R2 (13 μm).
Column:
— size: l = 0.25 m, Ø = 4 mm;
— stationary phase: strongly basic anion-exchange resin for chromatography R2 (13 μm).
Mobile phase: Dissolve 0.143 g of sodium hydrogen carbonate R and 0.191 g of anhydrous sodium carbonate R in water for chromatography R and dilute to 1000 mL with the same solvent.
Flow rate: 2 mL/min.
Detection: Conductivity detector equipped with a suitable ion suppressor.
Injection: 50 μL.
Run time: 1.5 times the retention time of oxalate.
Retention time: Sulfate = about 8.1 min; oxalate = about 10.6 min.
System suitability: Reference solution (b):
— repeatability: maximum relative standard deviation of 2.0 per cent for the area of the peak due to oxalate, determined on 5 injections;
— resolution: minimum 4.0 between the peaks due to sulfate and oxalate.
Calculation of content:
— for oxalates, use the concentration of sodium oxalate in reference solution (a).
Limit:
— oxalates: maximum 100 ppm.
Sucrose and reducing sugars
Dissolve 0.5 g in a mixture of 2 mL of hydrochloric acid R1 and 10 mL of water R. Boil for 5 min, allow to cool, add 10 mL of sodium carbonate solution R and allow to stand for 10 min. Dilute to 25 mL with water R and filter. To 5 mL of the filtrate add 2 mL of cupri-tartaric solution R and boil for 1 min. Allow to stand for 2 min. No red precipitate is formed.
Chlorides (2.4.4)
Maximum 50 ppm.
To 10 mL of previously filtered solution S add 5 mL of water R.
Phosphates (2.4.11)
Maximum 100 ppm.
Dilute 1 mL of solution S to 100 mL with water R.
Sulfates (2.4.13)
Maximum 50 ppm, determined on previously filtered solution S.
Prepare the standard using a mixture of 7.5 mL of sulfate standard solution (10 ppm SO4) R and 7.5 mL of distilled water R.
Iron
Maximum 5 ppm.
Atomic absorption spectrometry (2.2.23, Method I).
Test solution: Introduce 2.0 g into a 100 mL polytetrafluoroethylene beaker and add 5 mL of nitric acid R. Boil, evaporating almost to dryness. Add 1 mL of strong hydrogen peroxide solution R and evaporate again almost to dryness. Repeat the hydrogen peroxide treatment until a clear solution is obtained. Using 2 mL of nitric acid R, transfer the solution into a 25 mL volumetric flask. Dilute to 25.0 mL with dilute hydrochloric acid R. In the same manner, prepare a compensation solution using 0.65 g of calcium chloride R1 instead of the substance to be examined.
Reference solutions: Prepare the reference solutions from iron standard solution (20 ppm Fe) R, diluting with dilute hydrochloric acid R.
Source: Iron hollow-cathode lamp.
Wavelength: 248.3 nm.
Atomisation device: Air-acetylene flame.
Carry out a basic correction using a deuterium lamp.
Magnesium and alkali metals
Maximum 0.4 per cent.
To 0.50 g add a mixture of 1.0 mL of dilute acetic acid R and 10.0 mL of water R and rapidly boil, whilst shaking, until completely dissolved. To the boiling solution add 5.0 mL of ammonium oxalate solution R and allow to stand for at least 6 h. Filter through a sintered-glass filter (1.6) (2.1.2) into a porcelain crucible. Carefully evaporate the filtrate to dryness
and ignite. The residue weighs not more than 2 mg.
Bacterial endotoxins (2.6.14)
Less than 167 IU/g.
Microbial contamination
TAMC: acceptance criterion 10 CFU/g (2.6.12).
ASSAY
Dissolve 0.350 g in 20 mL of hot water R, allow to cool and dilute to 300 mL with water R. Carry out the complexometric titration of calcium (2.5.11). Use 50 mg of calconecarboxylic acid triturate R.
1 mL of 0.1 M sodium edetate is equivalent to 44.84 mg of C12H22CaO14,H2O.
