Calcium Glycerophosphate

Synonyms: glycerol phosphate calcium salt
cas number: 27214-00-2, molecular weight: 210.13, chemical formula: c3h7cao6p, einecs ec number: 248-328-5, fema: ----,
calcium glycerophosphate bp
ph eur
c3h7cao6p -- 210.1 -- 27214-00-2
action and use: excipient.
Definition
mixture in variable proportions of the calcium salt of 2,3-dihydroxypropyl phosphate and of 2-hydroxy-1-(hydroxymethyl)ethyl phosphate which may be hydrated.
Content: 18.6 per cent to 19.4 per cent of ca (dried substance).
Characters
appearance: white or almost white powder, hygroscopic.
Solubility: sparingly soluble in water, practically insoluble in ethanol (96 per cent).
Identification
a. Mix 1 g with 1 g of potassium hydrogen sulphate in a test tube fitted with a glass tube. Heat strongly and direct the white vapour towards a piece of filter paper impregnated with a freshly prepared 10 gl solution of sodium nitroprusside. The filter paper develops a blue colour in contact with piperidine.
B. Ignite 0.1 g in a crucible. Take up the residue with 5 ml of nitric acid and heat on a water-bath for 1 min. Filter. The filtrate gives reaction of phosphates.
C. It gives reaction of calcium.
Tests
solution s: dissolve 1.5 g at room temperature in carbon dioxide-free water prepared from distilled water and dilute to 150 ml with the same solvent.
Appearance of solution: solution s is not more opalescent than reference suspension.
Acidity or alkalinity: to 100 ml of solution s add 0.1 ml of phenolphthalein solution. Not more than 1.5 ml of 0.1 m hydrochloric acid or 0.5 ml of 0.1 m sodium hydroxide is required to change the colour of the indicator.