Packaging and storage—
Preserve in tight, light-resistant containers.
Identification—
B:
Ultraviolet Absorption 
197U
—
Solution:
50 µg per mL.
Medium:
methanol.
Absorptivities at 260 nm, calculated on the dried basis, do not differ by more than 3.0%.
pH 791:
between 4.6 and 5.1, in a solution (1 in 100).
Ordinary impurities 466—
Test solution:
chloroform.
Standard solution:
chloroform.
Eluant:
a mixture of cyclohexane, chloroform, and diethylamine (75:15:10).
Visualization:
1.
Organic volatile impurities, Method I 467:
meets the requirements.
Assay—
Dissolve about 400 mg of Carbinoxamine Maleate, previously dried and accurately weighed, in 50 mL of glacial acetic acid, add 1 drop of
crystal violet TS, and titrate with 0.1 N perchloric acid VS to a blue-green endpoint. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 20.34 mg of C
16H
19ClN
2O·C
4H
4O
4.
;)
-[2-(dimethylamino)ethoxy]benzyl]pyridine maleate (1:1)
for 2 hours, contains not less than 98.0 percent and not more than 102.0 percent of C16H19ClN2O·C4H4O4.