A: Infrared Absorption 197K— Obtain the test specimen as follows. Remove as completely as possible the contents of 5 Capsules, and dissolve, with shaking, in 10 mL of chloroform. Filter, and evaporate the chloroform solution to dryness. Proceed as directed with the dry residue so obtained and USP Altretamine RS.

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

Medium: 0.1 N hydrochloric acid; 900 mL.

Apparatus 1: 100 rpm.

Time: 30 minutes.

Procedure— Determine the amount of C9H18N6 dissolved from UV absorbances at 242 nm on filtered portions of the solution under test, suitably diluted if necessary with Dissolution Medium, in comparison with a Standard solution having a known concentration of USP Altretamine RS in the same Medium.

Tolerances— Not less than 80% (Q) of the labeled amount of C9H18N6 is dissolved in 30 minutes.

(Official January 1, 2007)

Buffer solution, Diluent, Mobile phase, Standard preparation, and Chromatographic system— Prepare as directed in Altretamine.

Assay preparation— Remove as completely as possible the contents of not fewer than 20 Capsules, and weigh accurately. Mix the combined contents, and transfer as completely as possible to a 500-mL volumetric flask. Add 325 mL of methanol, and sonicate. Dilute with water to volume, and mix. Transfer an accurately measured volume of this solution, equivalent to about 10 mg of altretamine, to a 200-mL volumetric flask, dilute with Diluent to volume, and mix.

Procedure— Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of altretamine (C9H18N6) in the portion of Capsules taken by the formula: in which C is the concentration, in mg per mL, of USP Altretamine RS in the Standard preparation; and rU and rS are the altretamine peak responses obtained from the Assay preparation and the Standard preparation, respectively.