Ketoprofen Capsules
Action and use
Cyclo-oxygenase inhibitor; analgesic; anti-inflammatory.
Definition
Ketoprofen Capsules contain Ketoprofen.
Content of ketoprofen, C16H14O3
92.5 to 107.5% of the stated amount.
Identification
Shake a quantity of the contents of the capsules containing 0.5 g of Ketoprofen with 50 mL of chloroform for 5 minutes, filter, evaporate to dryness using a rotary evaporator and induce crystallisation by prolonged scratching of the side of the container with a glass rod. The infrared absorption spectrum of the crystals, Appendix II A, is concordant with the reference spectrum of ketoprofen (RS 198).
Tests
Dissolution
Comply with the requirements for Monographs of the British Pharmacopoeia in the dissolution test for tablets and capsules, Appendix XII B1.
Carry out the method for liquid chromatography, Appendix III D, using the following solutions.
Calculate the total content of ketoprofen, C16H14O3, in the medium taking 662 as the value of A(1%, 1 cm) at the maximum at 260 nm.
Related substances
Carry out the method for liquid chromatography, Appendix III D, using the following freshly prepared solutions.
Solvent A A mixture of 40 volumes of acetonitrile and 60 volumes of water.
When the chromatograms are recorded using the prescribed conditions, the relative retentions with reference to ketoprofen (retention time about 8 minutes) are: impurity A, about 0.3 and impurity C, about 1.6.
2 volumes of freshly prepared phosphate buffer pH 3.5, 43 volumes of acetonitrile and 55 volumes of water.
The test is not valid unless, in the chromatogram obtained with solution (5), the resolution between the peaks due to ketoprofen and impurity A is at least 7.0.
In the chromatogram obtained with solution (1):
the area of any peak corresponding to impurity C is not greater than the area of the principal peak in the chromatogram obtained with solution (3) (0.2%);
the area of any peak corresponding to impurity A is not greater than the area of the principal peak in the chromatogram obtained with solution (4) (0.3%);
the area of any other secondary peak is not greater than the area of the principal peak in the chromatogram obtained with solution (2) (0.2%);
the sum of the areas of all the secondary peaks other than those due to the two named impurities is not greater than 2.5 times the area of the principal peak in the chromatogram obtained with solution (2) (0.5%).
Disregard any peak with an area less than the area of the principal peak in the chromatogram obtained with solution (6) (0.02%).
assay
Shake a quantity of the mixed contents of 20 capsules containing 50 mg of Ketoprofen for 10 minutes with 300 mL of methanol (75%), mix and dilute to 500 mL with methanol (75%). Allow to stand, dilute 5 mL of the supernatant liquid to 100 mL with methanol (75%) and measure the absorbance of the resulting solution at the maximum at 258 nm, Appendix II B. Calculate the content of C16H14O3 taking 662 as the value of A(1%, 1 cm) at the maximum at 258 nm.
IMPURITIES
The impurities limited by the requirements of this monograph include impurities A and C listed under Ketoprofen.