Flurbiprofen Tablets

General Notices

Action and use

Cyclo-oxygenase inhibitor; analgesic; anti-inflammatory.

Definition

Flurbiprofen Tablets contain Flurbiprofen. They are coated.

The tablets comply with the requirements stated under Tablets and with the following requirements.

Content of flurbiprofen, C15H13FO2

92.5 to 107.5% of the stated amount.

Identification

Extract a quantity of the powdered tablets containing 0.5 g of flurbiprofen with 25 mL of acetone, filter, evaporate the filtrate to dryness with the aid of a current of air without heating and dry at 60° at a pressure of 2 kPa. The residue complies with the following tests.

A. The infrared absorption spectrum, Appendix II A, is concordant with the reference spectrum of flurbiprofen (RS 156).
B. Heat 0.5 mL of chromic–sulfuric acid mixture in a small test tube in a water bath for 5 minutes; the solution wets the side of the tube readily and there is no greasiness. Add 2 or 3 mg of the residue and heat in a water bath for 5 minutes; the solution does not wet the side of the tube and does not pour easily from the tube.
C. Melting point, about 114°, Appendix V A.

Related substances

Carry out the method for liquid chromatography, Appendix III D, using the following solutions. For solution (1) disperse a quantity of the powdered tablets containing 0.5 g of flurbiprofen in 50 mL of water, add 200 mL of acetonitrile, mix, centrifuge and use the supernatant liquid. For solution (2) dilute 1 volume of solution (1) to 100 volumes with a mixture of 45 volumes of acetonitrile and 55 volumes of water and further dilute 1 volume to 5 volumes with the same solvent mixture. Solution (3) contains 0.0010% w/v of 2-(biphenyl-4-yl)propionic acid BPCRS in a mixture of 45 volumes of acetonitrile and 55 volumes of water. For solution (4) dilute 1 volume of solution (1) to 200 volumes with solution (3).

The chromatographic procedure may be carried out using (a) a stainless steel column (15 cm × 3.9 mm) packed with octadecylsilyl silica gel for chromatography (5 µm) (Resolve 5µ is suitable), (b) a mixture of 5 volumes of glacial acetic acid, 35 volumes of acetonitrile and 60 volumes of water as the mobile phase with a flow rate of 1 mL per minute and (c) a detection wavelength of 254 nm.

Adjust the sensitivity so that the heights of the principal peaks in the chromatogram obtained with solution (4) are about 40% of full-scale deflection on the chart paper.

The test is not valid unless the resolution factor between the two principal peaks in the chromatogram obtained with solution (4) is at least 1.5.

In the chromatogram obtained with solution (1) the area of any peak corresponding to 2-(biphenyl-4-yl)propionic acid is not greater than the area of the peak in the chromatogram obtained with solution (3) (0.5%), the area of any other secondary peak is not greater than the area of the peak in the chromatogram obtained with solution (2) (0.2%) and the sum of the areas of any secondary peaks is not greater than five times the area of the peak in the chromatogram obtained with solution (2) (1%).

Assay

Weigh and powder 20 tablets. Shake a quantity of the powder containing 0.1 g of flurbiprofen with 60 mL of 0.1m sodium hydroxide for 5 minutes, dilute to 100 mL with 0.1m sodium hydroxide, filter if necessary and dilute 10 mL of the filtrate to 100 mL with the same solvent. Further dilute 10 mL to 100 mL with the same solvent and measure the absorbance of the resulting solution at the maximum at 247 nm, Appendix II B. Calculate the content of C15H13FO2 taking 802 as the value of A(1%, 1 cm) at the maximum at 247 nm.