(koe les' ter ol).
» Cholesterol is a steroid alcohol used as an emulsifying agent.
Packaging and storage Preserve in well-closed, light-resistant containers.
Solubility in alcohol Dissolve 500 mg in 50 mL of warm alcohol in a stoppered flask or cylinder, and allow to stand at room temperature for 2 hours: no deposit or turbidity is formed.
A: To a solution of 10 mg in 1 mL of chloroform add 1 mL of sulfuric acid: the chloroform acquires a blood-red color and the sulfuric acid shows a green fluorescence.
B: Dissolve about 5 mg in 2 mL of chloroform, add 1 mL of acetic anhydride, and follow with 1 drop of sulfuric acid: a pink color is produced, and it rapidly changes to red, then to blue, and finally to a brilliant green.
Melting range 741: between 147 and 150.
Specific rotation 781S: between 34 and 38.
Test solution: 20 mg, undried, per mL, in dioxane.
Acidity Dissolve 1.0 g in 10 mL of ether in a small flask, add 10.0 mL of 0.10 N sodium hydroxide, and shake for about 1 minute. Heat gently to expel the ether, and then boil for 5 minutes. Cool, dilute with 10 mL of water, add phenolphthalein TS, and titrate with 0.10 N sulfuric acid until the pink color just disappears, stirring the solution vigorously throughout the titration. Perform a blank determination (see Residual Titrations under Titrimetry 541). The difference between the number of mL of 0.10 N sulfuric acid consumed in the blank and the number of mL consumed in the test with the Cholesterol is not more than 0.3 mL.
Loss on drying 731 Dry it in vacuum at 60 for 4 hours: it loses not more than 0.3% of its weight.
Residue on ignition 281: not more than 0.1%.