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 197K—

Test specimen— To a volume of Injection, equivalent to about 20 mg of acepromazine maleate, add 2 mL of water and 3 mL of 2 N sodium hydroxide, and extract with two 5-mL portions 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 preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.

(Official January 1, 2007)

Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Acepromazine Maleate.

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

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