Thiotepa for Injection
» Thiotepa for Injection is Thiotepa, with or without added substances, that is suitable for parenteral use. It contains not less than 95.0 percent and not more than 110.0 percent of the labeled amount of thiotepa (C6H12N3PS).
Packaging and storage Preserve in Containers for Sterile Solids as described under Injections 1, and store in a refrigerator, protected from light.
Completeness of solution 641 The contents of 1 container dissolved in Sterile Water for Injection or other diluent as directed in the labeling to obtain a solution containing 3.75 mg of thiotepa per mL yields a clear solution.
Identification, Infrared Absorption 197S
Test and Standard solutionsUse the Assay solution and Standard solution prepared as directed in the Assay.
pH 791: between 5.5 and 7.5, in a solution, constituted as directed in the labeling, containing 10 mg of thiotepa per mL.
Bacterial endotoxins 85: not more than 6.25 USP Endotoxin Units per mg of thiotepa.
Other requirements It meets the requirements for Sterility Tests 71, Uniformity of Dosage Units 905, and Labeling under Injections 1.
Assay Remove, as completely as possible, the contents of not less than 20 containers of Thiotepa for Injection, weigh, and mix. Transfer an accurately weighed portion of the powder, equivalent to about 75 mg of thiotepa, to a suitable container, extract with three 5-mL portions of carbon disulfide, and filter the carbon disulfide extract with the aid of vacuum. Concentrate the combined filtrates under vacuum to approximately 5 mL. Transfer the carbon disulfide solution to a 10-mL volumetric flask with the aid of a few mL of carbon disulfide, and dilute with carbon disulfide to volume (Assay solution). Concomitantly determine the absorbances of this solution and a Standard solution of USP Thiotepa RS in the same medium having a known concentration of about 7.5 mg per mL (Standard solution), in 0.1-mm cells, at the wavelength of maximum absorbance at about 10.75 µm, with a suitable IR spectrophotometer, using carbon disulfide as the blank. Calculate the quantity, in mg, of thiotepa (C6H12N3PS) in the portion of Thiotepa for Injection taken by the formula:
10C(AU / AS)in which C is the concentration, in mg per mL, of USP Thiotepa RS in the Standard solution; and AU and AS are the absorbances of the Assay solution and the Standard solution, respectively.
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USP32NF27 Page 3731Pharmacopeial Forum: Volume No. 26(6) Page 1574