Pyrazinamide
;)
Pyrazinecarboxamide.
Pyrazinecarboxamide [98-96-4].
»Pyrazinamide contains not less than 99.0percent and not more than 101.0percent of C5H5N3O,calculated on the anhydrous basis.
Packaging and storage—
Preserve in well-closed containers.
Identification—
A:
Infrared Absorption á197Mñ.
Solution:
10µg per mL.
Medium:
water.
Absorptivities at 268nm,calculated on the dried basis,do not differ by more than 3.0%.
C:
Boil 20mg with 5mLof 5Nsodium hydroxide:the odor of ammonia is perceptible.
and 191
Water,Method Iá921ñ:
not more than 0.5%.
Residue on ignition á281ñ:
not more than 0.1%.
Heavy metals,Method IIá231ñ:
0.001%.
Organic volatile impurities,Method Iá467ñ:
meets the requirements.
Assay—
Place about 300mg of Pyrazinamide,accurately weighed,in a 500-mL Kjeldahl flask,dissolve in 100mLof water,and add 75mLof 5Nsodium hydroxide.Connect the flask by means of a distillation trap to a well-cooled condenser,the delivery tube of which dips into 20mLof boric acid solution (1in 25)contained in a suitable receiver.Boil gently for 20minutes,avoiding insofar as possible distilling any of the liquid,then boil vigorously to complete the distillation of the ammonia.Cool the liquid in the receiver if necessary,add methyl purple TS,and titrate with 0.1Nhydrochloric acid VS.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nhydrochloric acid is equivalent to 12.31mg of C5H5N3O.
Auxiliary Information—
Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1680
Phone Number:1-301-816-8394