Methacholine Chloride
;)
1-Propanaminium,2-(acetyloxy)-N,N,N-trimethyl-,chloride,(±)-.
(±)-(2-Hydroxypropyl)trimethylammonium chloride acetate [62-51-1].
»Methacholine Chloride,dried at 105
for 4hours,contains not less than 98.0percent and not more than 101.0percent of C8H18ClNO2.
for 4hours,contains not less than 98.0percent and not more than 101.0percent of C8H18ClNO2.
Packaging and storage—
Preserve in tight containers.
Identification—
A:
Dissolve about 100mg in about 2mLof water on a watch glass,and add 3mLof platinic chloride TS:small rhombohedric plates are formed,which melt between 220and 225(see Melting Range or Temperature á741ñ)(distinction from acetylcholine chloride,which forms needles radiating from a central point,and from choline chloride,which forms no crystals).
and 225(see Melting Range or Temperature á741ñ)(distinction from acetylcholine chloride,which forms needles radiating from a central point,and from choline chloride,which forms no crystals).
B:
To 1mLof a solution (1in 10)add 1mLof alcohol and 1mLof sulfuric acid,and heat gently:the odor of ethyl acetate is perceptible.
C:
To 5mLof a solution (1in 10)add 2g of potassium hydroxide and heat gently:the odor of trimethylamine is perceptible.
D:
Asolution (1in 50)responds to the tests for Chloride á191ñ.
Melting range á741ñ—
Dissolve about 100mg in 2to 3mLof chloroform in a small beaker.Heat at 110for 1hour.While the test specimen is still hot,quickly powder the dry residue with a glass rod,and transfer to a melting point tube in the usual manner.Determine the melting range without delay.It melts between 170and 173.
for 1hour.While the test specimen is still hot,quickly powder the dry residue with a glass rod,and transfer to a melting point tube in the usual manner.Determine the melting range without delay.It melts between 170and 173.
Loss on drying á731ñ—
Dry it at 105for 4hours:it loses not more than 1.5%of its weight.
for 4hours:it loses not more than 1.5%of its weight.
Residue on ignition á281ñ:
not more than 0.1%.
Acetylcholine chloride—
To 2mLof a solution (1in 10)add 3mLof a solution of sodium perchlorate (1in 5),shake,and immerse in ice water for 5minutes:no precipitate is formed.
Heavy metals,Method IIá231ñ:
0.002%.
Assay—
Transfer to a conical flask about 400mg of Methacholine Chloride,previously dried and accurately weighed (because it is very hygroscopic,store the dried material in a vacuum desiccator),dissolve it in 50mLof glacial acetic acid,add 10mLof mercuric acetate TSand 1drop of crystal violet TS,and titrate with 0.1Nperchloric acid VSto a blue-green endpoint.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 19.57mg of C8H18ClNO2.
Auxiliary Information—
Staff Liaison:Salvador C.Salado,M.S.,Scientist and Latin American Liaison
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 1232
Phone Number:1-301-816-8165