Packaging and storage—
Preserve in tight, light-resistant containers.
Identification—
B:
Dissolve 50 mg in water in a 100-mL volumetric flask, dilute with water to volume, and mix (Stock solution). Transfer 4.0 mL of this solution to a 100-mL volumetric flask, and add 25 mL of pH 7.0 Buffer solution. (Prepare the pH 7.0 Buffer solution by dissolving 22.73 g of anhydrous dibasic sodium phosphate and 14.52 g of monobasic potassium phosphate in water to make 1000.0 mL. Dilute 25 mL of the buffer with water to 100 mL: the pH, determined potentiometrically, is 7.0 ± 0.05.) Dilute with water to volume, and mix (Solution A). Transfer 20.0 mL of the Stock solution to a 100-mL volumetric flask, add 25 mL of the pH 7.0 Buffer solution, dilute with water to volume, and mix (Solution B): the UV absorption spectrum of Solution A exhibits a maximum at 234 ± 1 nm, and the UV absorption spectrum of Solution B exhibits a maximum at 285 ± 2 nm.
C:
To 5 mL of a solution (1 in 5000) add 2 mL of a 1 in 100 solution of p-dimethylaminobenzaldehyde in alcohol: a yellow color develops immediately.
D:
A solution (1 in 100) responds to the tests for
Chloride 
191
.
pH 791:
between 2.5 and 3.0, in a solution (1 in 20).
Loss on drying 731—
Dry it at a pressure below 5 mm of mercury at 100
for 2 hours: it loses not more than 1.0% of its weight.
Chloride content—
Dissolve about 200 mg, accurately weighed, in 50 mL of water in a glass-stoppered flask. Add 25.0 mL of 0.1 N silver nitrate VS, then add 5 mL of 2 N nitric acid and 5 mL of nitrobenzene, shake vigorously, add 2 mL of
ferric ammonium sulfate TS, and titrate the excess silver nitrate with 0.1 N ammonium thiocyanate VS. Each mL of 0.1 N silver nitrate is equivalent to 3.545 mg of Cl: the content of Cl is between 16.0% and 17.2%.
Assay—
Dissolve about 200 mg of Anileridine Hydrochloride, accurately weighed, in 10 mL of glacial acetic acid by heating on a steam bath. Cool immediately in a cold water bath, add 5 mL of
mercuric acetate TS, 20 mL of acetone, and 0.5 mL of indicator solution (70 mg of
-naphtholbenzein, 10 mg of crystal violet, and 40 mg of quinaldine red in 100 mL of glacial acetic acid), and titrate with 0.1 N perchloric acid VS to a gray-green endpoint. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 21.27 mg of C
22H
28N
2O
2·2HCl.
