Cyclophosphamide Tablets
Action and use
Cytotoxic alkylating agent.
Definition
Cyclophosphamide Tablets contain Cyclophosphamide. They are coated.
Content of cyclophosphamide, C7H15Cl2N2O2P,H2O
92.5 to 107.5% of the stated amount.
Identification
Tests
Acidity
Shake a quantity of the powdered tablets containing 0.25 g of Cyclophosphamide with 20 mL of carbon dioxide-free water, filter and titrate the filtrate with 0.1m sodium hydroxide VS using phenolphthalein solution R1 as indicator. Not more than 0.2 mL of 0.1m sodium hydroxide VS is required to change the colour of the solution.
Related substances
Carry out the method for thin-layer chromatography, Appendix III A, using the following solutions.
2 volumes of anhydrous formic acid, 4 volumes of acetone, 12 volumes of water and 80 volumes of butan-2-one.
In the chromatogram obtained with solution (1):
any secondary spot is not more intense than the spot in the chromatogram obtained with solution (2) (1%).
Disregard any spot remaining on the line of application.
Assay
Weigh and powder 20 tablets. Dissolve a quantity of the powdered tablets containing 0.1 g of Cyclophosphamide in 30 mL of chloroform, shake vigorously for 15 minutes, filter (Whatman GF/F is suitable) and wash the filter with 15 mL of chloroform. Evaporate the combined filtrate and washings to dryness and dissolve the residue in 50 mL of a 0.1% w/v solution of sodium hydroxide in ethane-1,2-diol. Boil under a reflux condenser for 30 minutes and allow to cool. Rinse the condenser with 25 mL of water, add 75 mL of propan-2-ol, 15 mL of 2m nitric acid, 10 mL of 0.1m silver nitrate VS and 2 mL of ammonium iron(iii) sulfate solution R2 and titrate with 0.1m ammonium thiocyanate VS. Each mL of 0.1m silver nitrate VS is equivalent to 13.94 mg of C7H15Cl2N2O2P,H2O.