NOTE—Throughout the following procedures,protect test or assay specimens,the Reference Standard,and solutions containing them,by conducting the procedures without delay,under subdued light,or using low-actinic glassware.

A: Infrared Absorption á197Kñ—

Test specimen— To a volume of Injection,equivalent to about 20mg of acepromazine maleate,add 2mLof water and 3mLof 2Nsodium hydroxide,and extract with two 5-mLportions of cyclohexane.Combine the cyclohexane extracts,and evaporate to dryness under vacuum,using gentle heat,if necessary.

B: The retention time of the major peak for acepromazine in the chromatogram of the Assay preparationcorresponds to that in the chromatogram of the Standard preparation,as obtained in the Assay.

Mobile phase,Standard preparation,andChromatographic system— Proceed as directed in the Assayunder Acepromazine Maleate.

Assay preparation— Transfer an accurately measured volume of Injection,equivalent to about 100mg of acepromazine maleate (C19H22N2OS·C4H4O4),to a 100-mLvolumetric flask,dilute with 0.05Nhydrochloric acid to volume,and mix.Transfer 5.0mLof this solution to a 50-mLvolumetric flask,dilute with water to volume,and mix.

Procedure— Proceed as directed for Procedurein the Assayunder Acepromazine Maleate.Calculate the quantity,in mg,of acepromazine maleate (C19H22N2OS·C4H4O4)in each mLof the Injection taken by the formula: in which Vis the volume,in mL,of Injection taken;and the other terms are as defined therein.