Packaging and storage
Preserve in well-closed, light-resistant containers. Store at 25
, excursions permitted between 15
and 30
.
USP Reference standards 11
USP Methotrimeprazine RS.
NOTEThroughout the following procedures, protect test or assay specimens, the USP Reference Standard, and the solutions containing them, by conducting the procedures without delay, under subdued light, or using low-actinic glassware.
Identification
B: Ultraviolet Absorption 197U
Solution:
7 µg per mL.
Medium:
alcohol.
Absorptivities at 255 nm, calculated on the dried basis, do not differ by more than 3.0%.
Selenium 291
The absorbance of the solution from the
Test Solution, prepared with 100 mg of Methotrimeprazine and 100 mg of magnesium oxide, is not greater than one-half that from the
Standard Solution (0.003%).
Assay
Dissolve about 700 mg of Methotrimeprazine, accurately weighed, in 100 mL of chloroform, add 1 drop of a 1 in 500 solution of crystal violet in chloroform, and titrate with 0.1 N perchloric acid VS to the first disappearance of the violet tinge. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 32.85 mg of C19H24N2OS.
Auxiliary Information
Staff Liaison :
Clydewyn M. Anthony, Ph.D., Scientist
Expert Committee : (MDCCA05) Monograph Development-Cough Cold and Analgesics
USP29NF24 Page 1385
Pharmacopeial Forum : Volume No. 29(6) Page 1931
Phone Number : 1-301-816-8139