C7H16ClNO2 181.66

Ethanaminium,2-(acetyloxy)-N,N,N-trimethyl-,chloride.
Choline acetate (ester)chloride [60-31-1].

Packaging and storage— Preserve in tight container,and store at controlled room temperature.

USP Reference standards á11ñ— USP Acetylcholine Chloride RS.

Identification—

Melting range,Class Iá741ñ: between 149and 152.

Acidity— Dissolve 100mg in 10mLof recently boiled water,and add at once 1drop of bromothymol blue TS:not more than 0.50mLof 0.010Nsodium hydroxide is required in order to produce a color change.

Loss on drying á731ñ— Dry it at 105for 3hours:it loses not more than 1.0%of its weight.

Residue on ignition á281ñ: not more than 0.2%.

Organic volatile impurities,Method Iá467ñ: meets the requirements.

Chloride content— Transfer about 280mg,accurately weighed,to a porcelain casserole,and add 140mLof water and 1mLof dichlorofluorescein TS.Mix,and titrate with 0.1Nsilver nitrate VSuntil the silver chloride flocculates and the mixture acquires a faint pink color.Each mLof 0.1Nsilver nitrate is equivalent to 3.545mg of Cl.Not less than 19.3%and not more than 19.8%of Cl,calculated on the dried basis,is found.

Assay— Weigh accurately about 400mg of Acetylcholine Chloride,and dissolve in 15mLof water in a glass-stoppered conical flask.Add 40.0mLof 0.1Nsodium hydroxide VS,and heat on a steam bath for 30minutes.Insert the stopper,allow to cool,add phenolphthalein TS,and titrate the excess alkali with 0.1Nsulfuric acid VS.Perform a blank determination (see Residual Titrationsunder Titrimetry á541ñ).Each mLof 0.1Nsodium hydroxide is equivalent to 18.17mg of C7H16ClNO2.

Expert Committee:(PA3)Pharmaceutical Analysis 3

USP28–NF23Page 45

Phone Number:1-301-816-8330